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Hey Raiders, The combination of my birthday last week and two weeks of exams has kept me busy! At last, I can get on the 'net! Enjoy the news: Shark gives birth despite lack of mate Betty Reid The Arizona Republic September 18 Students at Carl Hayden Community High School were stunned when a baby shark appeared in one of their fish tanks. More amazing was that the mother shark had been in the tank alone for nearly four years. Teacher Fredi Lajvardi and his Phoenix science students investigated and discovered that the birth is rare. As far as we know, it is the third case worldwide. This type of birth is known as parthenogenesis, in which an unfertilized egg develops into a new pup, said Lajvardi, program manager for the Carl Hayden Center for Marine Science. "The mother's gene divides in half and recombines with its own collection of genes to create a new individual," Lajvardi said. "Normally, it would recombine with the father's half of the gene. But because there is no father, the mother provided the other half." It was a learning moment for students who saw firsthand last week how through parthenogenesis a species can reproduce when a mate isn't present. The week-old pup, whom students have named Dawn, was born to a white-spotted bamboo shark named Twilight, who has lived in one of the school's marine-science classrooms. "When we found out it hatched, everyone rushed the tank," said Kristen Shriner, a 17-year-old senior who has overseen the care of the mother shark. She and other students have been e-mailing scientists to find out how to properly care for Dawn. For now, Dawn will remain at the school; outside scientists have been invited to visit. GM glowing fish could be sold The Sydney Morning Herald September 12 Genetically-modified glowing fish are one step closer to being offered for sale in Australia to would-be pet owners looking for something a little different for their fish tank. A United States-based biotechnology company applied earlier this year to the Gene Technology Regulator for permission to import and sell the so-called GloFish. The zebra fish have been modified to include a fluorescent protein gene that comes from reef coral. The gene makes the fish absorb light and then release it, so they appear to glow either red, green or yellow. According to the latest report from the Gene Technology Regulator, consultation with experts and key stakeholders was held between April and June to identify any risks to human health and safety and the environment. The regulator said its technical advisory committee found the fluorescent proteins were not likely to be toxic to humans or other organisms, or cause an allergic reaction. The regulator noted the fish were already being sold in the US and Singapore. On its website, Yorktown Technologies said the fish were originally bred to help detect environmental pollutants. Scientists hope to modify the fish further so they only glow when they are in contaminated waterways. The company's website cautions against releasing the fish into the wild, saying the tropical fish would not survive in non-tropical environments. But some environmental activist groups including Greenpeace oppose the sale of the fish. "We have no way of predicting what havoc they will cause when they are released into the wild," Greenpeace says on its website. "Aquarium fish get introduced into native ecosystems all the time, and can survive in the warmer waters of some springs and around industrial wastewater pipes, so this really is no laughing matter. Any escape would be irreversible." The company also warns pet owners should not eat the glowing fish. "GloFish fluorescent zebra fish, like all ornamental fish, are not intended for human consumption; they should never be eaten," it says. Fish in space help studies of balance disorders Scientists seek answers to how the inner ears develop in microgravity. By Ned Stafford News @ Nature.com Twenty-six baby fish are now orbiting Earth aboard an unmanned Russian spacecraft, in a long-delayed experiment that researchers hope will lead to a better understanding of inner-ear balance mechanisms in humans. The cichlid fish (Oreochromis mossambicus) blasted off Friday morning (11:00 GMT) from Baikonur Cosmodrome in Kazakhstan, in a Foton-M3 craft atop a Soyuz-U rocket, as part of a package of life and physical science experiments organized by the European Space Agency. Reinhard Hilbig and Ralf Anken, neuro- and developmental biologists at the University of Hohenheim in Germany, will monitor the larval fish to watch the growth of their otoliths — sensory organs that have a role in hearing and balance — in microgravity conditions during the 12-day mission. Otoliths, also found in the inner ear of humans, are sensitive to gravity and linear acceleration and are essential for maintaining proper balance. They are composed of a mix of gelatinous material and calcium carbonate, which shift around in a viscous fluid when the head moves, stimulating hair cells and conveying information about movement to the brain. Scientists think a misfunctioning otolith is the culprit for conditions such as Ménière's disease, which causes vertigo and 'ringing in the ears' in sufferers. But they do not yet understand exactly how this organ works. The otoliths of fish provide a good candidate for study, says Hilbig, because they function in exactly the same way as human ones but are considerably larger. This is because fish must orient themselves underwater, where other motion clues are suppressed. Gravity groove Previous tests have shown that larval fish exposed to 'hypergravity' conditions in a centrifuge grow smaller-than-normal otoliths than controls. This implies that otolith development is, at least in part, under neural control, says Anken. Somehow the fish brain signals the otolith to grow smaller, as it does not need to be as big or as sensitive in hypergravity as it would in normal conditions. The next step to confirm neural control is to test whether microgravity makes developing otoliths grow to be larger (and so more sensitive) than normal. Anken says they are expecting the otoliths to "grow uncontrollably and asymmetrically" in low gravity if under neural control. This would make the otolith an unusual bit of anatomy. "I am convinced that the mineralization of otoliths is the only known natural process of biomineralization that requires neuronal input," says Anken. It could also point the way to treatments: controlling the neuronal process that determines otolith size in humans could be used to help those with balance disorders. Such treatments are a long way off, says Anken. "We are still doing the basic research. We first have to know how the otolith works, then we may eventually develop a treatment." Frogs in space Scientific curiosity about the effect of gravity on the otolith is not new. In 1970, NASA sent two bullfrogs into space to look at the effect of weightlessness on their otoliths, specifically to study motion sickness. The new experiment differs in that it looks at the brain's involvement in otolith development. It is a course that Anken has been pursuing for years. "In 1998, NASA released an announcement for a space shuttle mission and we jumped on this train," he says. It turned out to be a slow ride. Their microgravity fish experiment was launched in early 2003 aboard the Columbia space shuttle, a mission that ended in tragedy on 1 February that year when the shuttle disintegrated on re-entry over Texas. The fish experiment was lost along with the seven crew members. They now have a second chance. Their fish are housed in a special tank, holding 3 litres of water and tipping the scales at only 18 kilograms. Scientists can observe fish behaviour through a camera system that sends video streaming back to Earth. When the experiment crash-lands back on Earth, the fish will be retrieved for more detailed study. Fish and plant losses forecast as Murray level falls ABC News Online September 20 The latest report on the health of the Murray-Darling Basin says water levels in lower parts of the Murray could fall dramatically in the next year. The Murray-Darling Basin Contingency Planning Report says water levels below Blanchetown in South Australia are set to fall by almost one metre by next April and, in a worst case scenario, could drop by almost two metres by late next year. It says many fish could die in the lower lakes and salinity in Lake Alexandrina is set to reach a measure of 2500 EC early next year. The outlook for farmers is also grim. SA Water Security Minister Karlene Maywald says it is likely to become harder for people to obtain water. "People at Langhorne Creek, Currency Creek and the dairy industry and the vegetable industry around the lower lakes are going to have a very, very difficult year," she warned. The report says it is likely there will be widespread permanent plant losses across the Murray system because of insufficient water allocations. It says there could be even more pressure placed on irrigators with a recommendation that an emergency water reserve be established. The SA Government supports that recommendation, while the Victorian Government is opposed because of the expected effect on irrigators. But Mrs Maywald says critical human needs are the priority. Environment experts say low water levels are already having a devastating impact on native fish in the lower lakes of the Murray system. Sperm Transplant Between Fish May Preserve Endangered Species By Simeon Bennett Bloomberg.com September 14 Transplanting reproductive cells between fish may help preserve endangered species or resurrect extinct ones, scientists in Japan say. Researchers at Tokyo University of Marine Science and Technology injected immature sperm-creating cells from rainbow trout into salmon embryos with abnormal chromosomes to produce normal trout with healthy offspring. They also froze and thawed reproductive cells, known as spermatogonia, as a way to store genetic material of endangered fish. One objective is building ``a kind of spermatogonia bank of various fish species,'' said Goro Yoshizaki, who participated in the research, in a telephone interview yesterday. Transplanting the stored cells may enable scientists to revive species that become extinct, he said. Habitat destruction, over-fishing and the introduction of farmed fish to wild populations have caused some species in the U.S. and Japan to dwindle, including bull trout, golden trout and gila trout, Yoshizaki said. The Tokyo researchers are collaborating with the U.S. National Oceanic and Atmospheric Administration to freeze sperm from a population of endangered sockeye salmon from Idaho, he said. The transplant technique, reported in the journal Science today, is being use to produce bluefin tuna, prized in Japan for sushi and sashimi dishes. Rather than farming the tuna, which weigh as much as 600 kilograms (1,320 pounds), Yoshizaki is implanting their reproductive cells in mackerel, which are about 1,000 times smaller and can be farmed in smaller facilities, he said. ``If I take spermatogonia from tuna and transplant it into mackerel, that surrogated mackerel can produce tuna egg and sperm,'' Yoshizaki said. ``Then we could save a lot of cost and space and labor for tuna seed production.'' Three-quarters of world's fish stocks depleted: report ABC News Online September 19 An environmental report has found three-quarters of the world's fish stocks have been over-exploited, mainly by commercial fishing. The WorldWatch Institute study says declaring marine parks may be the only way to reverse a big decline in fish stocks across the world. It says there needs to be a radical change to fisheries management and has recommended that exclusion zones be introduced in the high seas. Greenpeace Oceans campaigner Jason Collins says that means more of the world's oceans need to be declared no fishing areas. "At the moment around the world, there's less than 1 per cent of the oceans that are in marine parks," he said. "Less than 0.1 per cent of the world's oceans are fully protected in that there can be no fishing. "That's a long way from the recommendations that are coming from reports like this, which are starting to point to much bigger figures such as protecting 40 per cent of the world's oceans from fishing." Flattieman.
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Fish lips: Putin kisses sturgeon Google News - AFP September 1 Politicians love to be shown kissing babies, but Russian President Vladimir Putin took on an altogether more slippery customer Friday by puckering up for a fish. The Kremlin leader, who is due to step down at the end of his second term next March, looked every bit the seasoned campaigner when he lifted the sturgeon at a fish farm in southern Russia and gave the creature a peck on the head. Onlookers at the farm in Selo Ikryanoye, near Astrakhan on the Caspian Sea, applauded when Putin, who was wearing white gloves, then dropped the sturgeon into the sea. The fish farm is part of efforts to regenerate the Caspian's endangered sturgeons, prized for their tiny black eggs used to make caviar. Unique fish fossil in northern Alberta may help explain migration patterns The Canadian Press - Google News September 5 They went drilling for oil in northern Alberta and instead dug up a one-of-a-kind, 96-million year-old fossilized fish small enough to fit in your palm, but big enough to yield clues on how sea critters migrated in the age of Tyrannosaurus rex. But to fish paleontologist Alison Murray, the Tycheroichthys dunvenganensis is also a big question mark. "It's complete fossil, which means it must have been killed and buried very, very quickly," said Murray, who now researches at the University of Alberta. "It wasn't scavenged or broken apart in wave action. It must have been some sort of sudden event that killed it and trapped it in mud." But based on the biology of its living relatives, the herring family, it is not the type of fish to have swum in muddy waters, she said. "So I'm not sure what it was doing there. He is an anomaly." It's a member of the extinct fish family Paraclupeidae. While other members of this family have been found in Lebanon, Morocco and Brazil, the Alberta find is a new genus entirely. The fossil, written up recently in the Canadian Journal of Earth Sciences, was actually unearthed two decades ago south of Grande Prairie in a core sample taken 1,325 metres below the surface by now-defunct Cequel Energy Inc. The fish was not found because Cequel was not interested in the sediment at the bottom of the core sample. It wasn't until a couple of years ago that geology student Michael Hay, checking out the core samples for his own research, came across the fossil and passed it on to Murray and others. It is now at the Canadian Museum of Nature in Ottawa. Murray said it was swimming in a monster seaway that had cleaved what is now North America in two in the late Cretaceous period. She said the find is further evidence of a direct water link between North America through Great Britain to the Mediterranean Sea, but also gives give credence to the theory of a direct water link from the Mediterranean through what is now Hudson Bay. "This one could support the Hudson Bay theory. We actually don't have the answer." She said the fish will also aid research in biogeography, to help understand how organisms evolved and moved into different areas. Coral Reef Fish Harbor An Unexpectedly High Biodiversity Of Parasites Science Daily September 5 IRD researchers showed that Epinephilus maculates, a fairly abundant species of grouper off New Caledonia, was parasitized by 12 species of microscopic monogenean worms. This diversity of parasites has just been confirmed also in the malabar grouper, Epinephilus malabaricus, another the coral reef species. If such a level of parasite diversity prevails in all coral-reef fish, tens of thousands of parasite species are in this ecosystem waiting to be discovered. In the same way as the tropical rainforest, the coral reefs of warm seas are among the richest ecosystems of the world in terms of their biodiversity. In fact the best conserved areas harbour over 700 species of coral, 600 species of mollusc and nearly 4000 species of fish. These fish have been well studied by reef biodiversity specialists over the past few years, yet still little is known about their parasites. Two studies conducted by IRD researchers of Noumea have brought out evidence of this parasite species richness in two grouper species of the New Caledonian coral reef. The new species described by the IRD taxonomists are microscopic animals less than 0.5 mm long. These tiny parasitic worms all belong to the class of monogeneans (Monogenea). They live on gills of marine fish where they find both refuge and food. Identification of each taxon is facilitated by the morphology of the genital apparatus which is characteristic for each species. In 2006, researchers from the research unit "Systématique, Adaptation, Évolution" (UMR 148) at Noumea first studied Epinephelus maculatus, a grouper species commonly called "loche grisette" and quite common in the New Caledonia lagoon. Microscopic observation of nearly 800 specimens of monogeneans collected from gills of 10 individuals of this fish allowed biologists to identify 12 different species. By comparison, the Mediterranean grouper (Epinephelus marginatus) are host to just four species belonging to this class of gill parasite. At least 10 of these monogeneans found in the New Caledonian "loche grisette" are strictly specific: they live exclusively on this fish. A second investigation focused on the malabar grouper (Epinephelus malabaricus, "mère loche"). It confirmed the diversity of monogenean gill parasites of the New Caledonian coral reef. For this second grouper species, 11 species of associated monogeneans were identified among more than 300 collected from the gills of two malabar specimens The existence of a rich fauna of monogeneans in the New Caledonia grouper was therefore confirmed. The ensuing article gives a detailed list of 44 parasite species already recorded in the malabar grouper in the whole of the Pacific Ocean. The malabar grouper has a high initial growth rate and the adult reaches 50 kg, making it a species highly prized by aquaculture operators in South-East Asia. Young malabar groupers are taken directly from their natural habitat in order to supply the fish farms. They are subsequently fattened up quickly, as are red tuna in the Mediterranean. As an example, the Thai production of this fish thus grew from 15 000 individuals in 1991 to 265 000 in 1995. Parasite control in such breeding conditions, where high density of fish populations favours high rates of parasite infection, is crucially important, as the parasitized specimens usually have a lower than average growth rate. Better knowledge of the parasite species present in wild malabar grouper populations could help improve rearing management. The IRD Noumea research team also substantiated the hypothesis that reef fish in general have an especially rich parasite biodiversity. The New Caledonian coral reef harbours nearly 2000 species of fish. Extrapolation of these results to the whole of this Pacific island's coral reef yielded an estimated fish parasite biodiversity of about 10 000 species. Extrapolating again, to such an aquatic ecosystem at the global scale can certainly give a figure two or three times as large. Biologists currently have very little knowledge about the host-parasite relation that links the monogeneans to the fish. Like all parasites, they must be closely tied with their host. The specificity the newly described monogenean species have to particular groupers shows this. The disappearance of one species of fish would threfore likely lead to that of the parasites associated with it. Hosts and parasites form a system that reaches a certain equilibrium as evolution proceeds. Destruction of this equilibrium could influence the regulation of fish populations, in letting the less strongly parasitized species become more invasive, and modify the structure of coral reef communities. Maintenance of this ecosystem in a good state is already seriously threatened by global warming, pollution and the development of tourism. Therefore it is more necessary than ever to conserve the entirety of this natural habitat. Low Oxygen In Coastal Waters Impairs Fish Reproduction August 31 Science Daily — Low oxygen levels in coastal waters interfere with fish reproduction by disrupting the fishes' hormones, a marine scientist from The University of Texas at Austin Marine Science Institute has found. Incidents of seasonal low levels of oxygen, known as hypoxia, have increased dramatically in coastal waters throughout the world over the past few decades, largely as a result of increased run-off from human agricultural and industrial activities. Hypoxia's long-term impact on marine animal populations is unknown. Dr. Peter Thomas found that both male and female fish collected from seasonally hypoxic waters in Florida's Pensacola Bay estuaries had little ovarian and testicular growth, low egg and sperm production, and low levels of reproductive hormones during a time a year when they would normally be increasing in preparation for reproduction. "This study provides the first clear evidence that a wild population of estuarine fish has experienced reproductive impairment through hypoxia," said Thomas, professor of marine science. "We rarely find such a dramatic reproductive impairment in both male and female fish collected from degraded environments, such as those contaminated with pollutants." Laboratory studies showed that hypoxia caused endocrine disruption through decreasing levels in the brain of a chemical important for brain function called serotonin. The decrease in serotonin was caused by a decrease in an enzyme that plays a role in the serotonin synthesis pathway. Atlantic croaker is one of the most common inshore fish species along the coasts of the southeastern Atlantic Ocean and Gulf of Mexico, and Thomas said that the croaker is representative of many inshore fish. "This study suggests that when persistent coastal hypoxia occurs, there is a potential long-term threat to fish populations and fishery resources," said Thomas. "With worldwide increases in hypoxia, it's something we must be concerned about, because so many people rely on fishing for their livelihood." Thomas' future studies will aim to further elucidate the effects of hypoxia on fish endocrine and reproductive systems at the molecular level. He is also pursuing similar work on reproductive impairment in croaker from hypoxic waters surrounding the so-called "Dead Zone" off the coast of Louisiana, which is an area of almost no oxygen that this year covered 7,900 square miles. Thomas' research was recently published online in Proceedings of the Royal Society B. Funding for this research was provided by the U.S. Environmental Protection Agency. Dr. Md. Saydur Rahman Dr. Izhar Khan and James Kummer contributed to the research. Flattieman.
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Fish versus AIDS The Economist August 30 Fish ponds are helping in the fight against AIDS Life for Agnes Kanyema is looking up. The retired teacher and her husband are caring for four of their grandchildren, whose parents have all died of AIDS. Their meagre pension is not enough, so they rely on farming to eat and make ends meet. Now, with the help of WorldFish Centre, a non-profit outfit based in Malaysia, Mrs Kanyema also runs a fish pond, which not only provides extra cash and protein but also helps her grow maize and vegetables on her small plot of less than a hectare (2.47 acres). Her pond provides water for crops during droughts and she uses the sediment as fertiliser. The fish and vegetables help feed her family, and she sells the surplus at the local market. The WorldFish Centre has helped 1,200 families who have lost breadwinners to AIDS to dig and run fish ponds in southern Malawi's Zomba district. The small landlocked southern African country relies heavily on subsistence farming. But HIV/AIDS, erratic rains, overpopulation and soil erosion are taking a big toll, making it hard for farmers on tiny plots to survive. With Malawi's main lake overfished, people are losing a big source of protein. In the 1970s they ate 14 kilos of fish per person a year; now they consume just four kilos. The ponds, which are easy to maintain, cost only $200 to make and $10 to stock with fish. They are filled from the water table or by nearby streams; rain keeps them going. The fish are fed from farm waste and by-products, such as chicken manure and maize bran. According to WorldFish, families with fish ponds have doubled their income and now eat 150% more fresh fish. Malnutrition among children under five has apparently dropped from 45% to 15% in three years. Mrs Kanyema passes on the training she has received on fish-breeding and on how to use her pond for agriculture to her neighbours. Pond owners sell most of their fish and vegetables locally, where there is enough demand to keep everything fresh. But they are also being taught to smoke fish, which keeps it for two weeks. Daniel Jamu, WorldFish's regional director, says that the next step is to help farmers club together to market their produce in the towns, where prices are higher. Many poor farmers are starting to view aquaculture as easier and cheaper than raising cattle. WorldFish is expanding the project to reach another 26,000 families in neighbouring Mozambique and Zambia, as well as Malawi. Fishers warned of coral reef fin fish restrictions ABC News Online August 30 Fines of up to $75,000 will soon apply to those caught fishing coral reef fin fish. It will be illegal to catch coral trout, cods, gropers, red emperors and parrot fish over three nine-day periods during October, November and December during the spawning season. The restrictions apply to Queensland's east coast. Department of Primary Industries and Fisheries' resource manager Dr Brigid Kerrigan says tough penalties apply to those who break the law. "These closures are very important. Commercial fishermen have the potential to target fish during these periods of time that the fish are aggregating to spawn, so it's another measure just to ensure that there's going to be plenty of coral reef fin fish out there on the reef for people to fish into the future," Dr Kerrigan said. Underwater noise harming fish ScienceDaily August 25 Man-made underwater noise threatens the health and reproductive capacity of many fish and marine mammals, an Italian researcher says. In an interview with the news agency Ansa, Fabrizio Borsani of the marine research institute ICRAM in Rome said noise is deadly to some species. He said fish with inflatable bladders like cod can even explode. Borsani recently attended the first international conference on marine noise held in Nyborg, Denmark. He said an increase in shipping and coastal construction, off-shore wind farms and oil drilling are responsible for increased underwater noise. The increase is even affecting fish farmers. He said farmed salmon in Canada and the United States are smaller if they are closer to sources of noise. In the Mediterranean, some whales are not reproducing because they do not hear mating calls, he said. Breeding a $5,000 fish How I turned my hobby of raising koi into a successful business By Joseph Zuritzky Owner, Quality Koi Co. CNNMoney.com August 27 I am the CEO of Parkway Corp., a Philadelphia company that operates 100 parking facilities in the U.S. My second business, breeding koi, started as a hobby. I bought about 40, to study what makes these beautiful fish so valuable. What is the best body shape? Is that brilliant red pattern going to disappear in six months, leaving the customer with an inferior fish? Many dealers base a koi's price on what it looks like today. We grade them according to what they'll look like over the years. I launched this operation in southern New Jersey in 2002. Most U.S. koi breeders sell to the mass market; I saw an opportunity to breed better-quality fish for serious hobbyists. Most U.S. dealers fly to Japan and buy everything but tategoi, the highest-quality koi. They are too expensive. A five-inch fish, which will live about 50 years, costs more than $1,400 wholesale. At Quality Koi (qualitykoi.com) we sell that same fish for less than $1,000. We breed 40 types of koi and sell 20,000 to 30,000 fish a year, 90% of which we sell wholesale to dealers. Their customers are hobbyists, who pay $15 to $5,000 a fish. Some have won prizes in fish shows against Japanese competitors. I've invested more in the farm than I ever thought I would. We expect to turn an operating profit at the end of this year, with revenues exceeding $500,000. We've had many surprises. Four years ago thousands of fish disappeared in one day. We tested the water and found nothing wrong. A Japanese consultant visited and told us, "You have to walk the ponds." With each step, you release methane trapped beneath the clay bottom. Unless you release the gas regularly, it can erupt with such force that it disintegrates the fish. After five years we're still learning how to run the farm. Fish and mushrooms still toxic from Chernobyl IOL News - South Africa August 28 Twenty-one years after the Chernobyl nuclear disaster in Ukraine, fish and mushrooms in parts of Finland are still toxic due to radioactive fallout, Finnish authorities said on Monday. The concentration of cesium-137 exceeded the EU maximum recommended level in 20 percent of fish and more than half of the mushrooms tested in 2005 by the Radiation and Nuclear Safety Authority and Finnish Food Safety Authority Evira. The tests were conducted in the lakes and region around Vammala, 230km north-west of Helsinki in south-western Finland - the Finnish area most affected by the fallout from the Chernobyl disaster on April 26, 1986. Radioactivity levels reached nearly three and a half times the maximum recommended level in fish and up to nine times the maximum in mushrooms, with significant variations depending on where the tests were carried out and other factors. Seventeen percent of fish also had elevated levels of mercury. Finnish authorities recommend consumers eat lake fish no more than once or twice a month - expectant mothers are advised to stay away from pike entirely during their pregnancy - and to wash mushrooms well before eating. Flattieman.
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Poisonous Puffer Fish Sold as Salmon Kill 15 in Thailand FOXNews.com August 23 In Thailand, it's a fish dish that kills. A doctor says unscrupulous vendors have been selling meat from the highly poisonous puffer fish disguised as salmon. That's resulted in the deaths of more than 15 people over the past three years. Some 115 people have been hospitalized. Although it was banned in Thailand five years ago, puffer fish continues to be sold in large quantities at local markets and restaurants. The ovaries, liver and intestines of the puffer fish contain a poison so potent that the U.S. Food and Drug Administration says it can "produce rapid and violent death." In Japan, the fish is called fugu (foo-goo) and is prepared by highly trained chefs and consumed by thrill-seeking Japanese gourmets. Every year, there are reports of people dying or falling sick in Asia from eating puffer fish. Scientists puzzled over fish tag that traveled 7,700 miles By Craig Welch, environment reporter Seattle Times, USA August 17 Bird researcher Dale Whaitiri was on an island off southern New Zealand examining the stomach contents of a baby seabird when an electronic device the size of a grain of rice spilled from the bird's gullet. The monitoring tag had been planted years before in a juvenile steelhead — on the Columbia River in the Pacific Northwest. But this chick was too young to fly — let alone eat fish. The discovery has launched a tale of scientific intrigue spanning 7,700 miles across the Pacific Ocean. How did the tag wind up in a fat, flightless bird about to be eaten by Maori tribesmen? And of the millions of seabirds — called sooty shearwaters, or "titi" by the Maoris — how did Whaitiri manage to poke this one's belly? "The odds are almost impossible to fathom," said Jen Zamon, a seabird expert for the Northwest Fisheries Science Center. The story really began in 2005, when a Northwest scientist stuffed the puny tag into the steelhead, chucked it into the Columbia and watched the signal blip off the radar when the fish passed the Bonneville Dam on its way to sea that spring. But then what? The little tags don't float. So it didn't drift to New Zealand to be eaten off the ocean's surface. Besides, sooty-shearwater chicks can barely move. They're often fatter than their parents, and they eat only when fed by adult birds. The silver, bullet-headed steelhead of the Columbia River have been snared as far away as the Bering Sea. But they migrate north, not south. "The fish didn't do the traveling," concluded Doug Marsh, a Seattle biologist for the fisheries science center, who learned last week that Whaitiri had found his fish tag in April. "So it must have been the bird." Actually, sooty shearwaters are no strangers to the Columbia River. They are known to travel tens of thousands of miles in search of warm weather, and often congregate at the river's mouth. Then they work their way north and west to Japan and south to New Zealand, where they nest high in the hills and lay eggs in underground burrows. The native Maori catch the delicious chicks for supper, but hand over the stomachs to Whaitiri and other researchers who monitor the birds' diets. So the answer may be elementary, Zamon said: A sooty shearwater ate the steelhead on the Columbia, carried the indigestible glass tag in its belly for two years, then regurgitated it into the baby's eager maw. But that's merely an educated guess. For all she knows, the tag "could have been abducted by aliens or something," she kids. "Who knows?" The mystery is a reminder of how much the northern and southern hemispheres are linked. And for the scientists, it raises other questions. There are tantalizing ones: We know shearwaters eat lots of squid, but how much salmon and steelhead do they down? And the silly: Given how many shearwaters traverse the continents, how many monitoring tags have been eaten by unknowing Maori? "I'm sure that question is being asked in New Zealand right now," Zamon said. The tags are harmless, and usually tucked into parts of fish that no one eats. And if eaten by a human, a tag would just pass through. Right? "There are rumors that some grad students have ... um ... done that," Zamon said. "Good luck finding one who'll admit it." Writer weighs in with good fish and tips By Wendy Frew, Environment Reporter Sydney Morning Herald August 24 Tim Winton loves the sea and he loves to fish. But the celebrated writer, whose novels are peopled with fishermen and coastal families, knows that fisheries are collapsing under the weight of commercial and recreational fishing. Since the early 1990s the number of overfished species in Australian waters has nearly quadrupled, a recent government report says. However, Winton said, few were aware that their demand for cheap, fresh seafood was supporting the growth of industrial-scale fishing. "I have spent so much of my life in and under the water, swimming, fishing and spear fishing," said the confessed "rec fishing, red-necked greenie". "I loved what I was doing, but I could see it changing and changing so fast that my children might not be able to experience it." Winton is in Sydney this week to remind consumers they can help turn the tide on unsustainable fishing practices. With the Sydney chef Kylie Kwong, Winton is a patron of the Australian Marine Conservation Society, which launched its updated sustainable seafood guide at Kwong's Surry Hills restaurant, Billy Kwong, last night. The Federal Government has given $250,000 to the Sydney Fish Markets to promote locally produced seafood, with a particular focus on under-fished species. As part of a broader program to support the profitability and sustainability of the fishing industry, the Government has bought back more than 550 fishing concessions, worth $149 million. It has also provided financial help to people disadvantaged by the reduction in fishing activity. Winton and the Australian Marine Conservation Society say marine parks, fishing quotas and the promotion of sustainable fishing practices are not an attack on fishermen but an attempt to protect threatened species, and ensure commercial and recreational fishermen have a future. In the expanded edition of the Sustainable Seafood Guide, orange roughy, southern blue-fin tuna and sea cage Atlantic salmon and barramundi are out. Wild abalone, Moreton Bay bugs and coral trout are questionable. But bream, flathead and King George whiting are good choices. The fisheries campaigner for the society, Craig Bohm, said it was not just where fish were caught that mattered, but how they were caught, whether they were cage-farmed or wild, what they were fed, and whether they were a slow-growing or a long-lived species likely to be vulnerable to overfishing. Fish lifts unlock the Murray for tiny migrants By Richard Macey Sydney Morning Herald August 21 For eons the mighty Murray River was a highway for migrating fish. Murray cod, golden perch and silver perch swam hundreds, possibly thousands of kilometres upstream to spawn. Saltwater black bream, jewfish and mullet from the Southern Ocean entered the mouth of the river at Goolwa, travelling far inland to feed. Then man started exploiting the rivers. It has been estimated that up to 10,000 dams, weirs, road crossings and locks have been built across the rivers of the Murray-Darling Basin. However, the structures also became barriers for fish, reducing their migration opportunities to times when the rivers flood, providing a way around the man-made obstacles, or when boat locks were briefly opened. It is believed the basin now has just one-tenth the fish it had before European settlement. The Murray-Darling Basin Commission's Sea to Hume Fishways Project, costing $45 million, aims to reopen the Murray for the first time in more than a century. By 2010 fish should able to travel 2250 kilometres, from the river's mouth to the man-made Lake Hume, east of Albury, circumventing 14 major barriers. Already 880 kilometres have been reopened to the finned migrants. For larger fish concrete canals, known as fishways, kept at least a metre deep, have proven adequate for bypassing man-made barriers. However, scientists researching the Murray's migrants found something unexpected. Traps put into the river revealed that huge numbers of very small fish, only centimetres long, were also attempting the journey. "There were Australian smelt, rainbow fish, hardy head and gudgeon," says Dr Lee Baumgartner, a freshwater fish ecologist with the NSW Department of Primary Industries. While it had been known they were there, no one had previously understood the scale of the annual migration attempted by the tiny swimmers. "Thousands of fish per day have been wanting to migrate up the Murray," Baumgartner says. "It changed our mindset on how we provide passage for fish." The concrete canals, rising about a metre for every 18 metres of length, were too steep for the smallest fish. The scientists and engineers considered canals with shallower grades, rising about one metre every 32 metres, but then came up with a better idea. "It turned out to be simpler to build locks for the smaller fish." The researchers experimented with a fish lock at Balranald, on the Murrumbidgee. "It worked really well," Baumgartner says. About 20 metres long and two metres wide, the Murray's five planned locks will be miniature, automated versions of the ones used by boats. Day and night the lock gates will open and shut, trapping the tiny fish inside. The water level will rise about six metres, the upper gate will open, and the tiny migrants will continue on their way. Since 2000 the scientists have micro-chipped almost 20,000 large fish to learn how far they migrate. "Some have gone up to 500 kilometres," Baumgertner says. "They can migrate a couple of hundred kilometres in a month." By voyaging as far as they can up river, he says, fish can increase the potential territory of their offspring. Catch of 6-foot sturgeon at river mouth a rare fish tale By Stephen Tait Newburyport Daily News - USA August 22 They grow to lengths of 15 feet, live for as long as six decades and are some of the most primitive animals in the waters of North America. Though resilient during their lives, Atlantic sturgeon are on the state's endangered list, which makes Jeff Hajjar's catch of a 6-footer about 50 yards from the north jetty at the mouth of the Merrimack River on Monday night all the more surprising. Hajjar, a Methuen native who now lives in Idaho, caught the fish using a 6-inch Sluggo - which looks like a rubber eel - on a two-ounce lead head jig. "He was a big son of a gun," he said. "We thought we caught some kind of giant shark at first." Hajjar said he was fishing with his brother, "and that was the first cast of the night, and we bring in this sturgeon. I couldn't believe it." Kristen Ferry, a biologist for the state Division of Marine Fisheries, is also surprised at the catch. "In my time working with sturgeon, I haven't learned of anyone catching a sturgeon in the Merrimack," she said. "It is not unheard of, but it is not at all common." Ferry said the Atlantic sturgeon is a migratory fish and moves up and down the East Coast of the United States. She said biologists will find a sturgeon that has originated from Southern states that has migrated to the bays and waterways of the Northeast. Because of that, she said there is an extensive tagging program for sturgeon to help biologists track their movements. "They are moving around all the time," she said. At 7:30 p.m. Monday, an Atlantic sturgeon just happened to be moving around the mouth of the Merrimack. Hajjar said when he first hooked the fish, he thought he might have caught a really big striped bass, a popular and much more common catch for that part of the river. "But then he just made a run straight out to the ocean, and I never felt a striper make a run like that," he said. "Then it was just like pulling in dead weight." Reeling the fish in, he said, was a struggle. "It took us forever to get that fish to the boat," Hajjar said. "We were going at it for 15 to 20 minutes. We didn't know what it was. We didn't have a clue of what was going on. "It was a lot of fun." When he finally reeled it to the boat, he said he immediately realized it was a sturgeon, which he said was shocking. But knowing that in Idaho the fish are protected, he figured the same must be true here. Instead of trying to bring the fish into the boat, Hajjar said his brother reached into the water and pulled out the hook. "We didn't want to lift it out of the water. I know how rare they are," he said. The origins of Atlantic sturgeon date back more than 120 million years and the animals grow to as big as 15 feet and 800 pounds, according the Chesapeake Bay Program, a restoration partnership for that body of water, which is a popular place for sturgeon to live and spawn. Sturgeon do not have scales but rather five rows of bony plates called scutes. They use their hard snout to look for food along the bottom of the waterways. They typically eat mollusks, insects and crustaceans. The first market for sturgeon on the East Coast started in 1628 in Brunswick, Maine, according to the Chesapeake Bay Program. Beyond food, the fish's skin was used as leather for clothing and book bindings. Sturgeon are still valuable, especially the roe, which is used for caviar that can fetch more than $250 a pound. The fish usually spawn in rivers. Juveniles stay in the fresh or brackish water for one to six years before moving out to the oceans. The fish tend to stay close to the shore when they become adults. Flattieman.
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First, a bit more on one of last week's stories: Fossil Fish Jaws Give Information On Our Own Remote Ancestors Science Daily August 17 The dentary from Andreolepis was found in Gotland, Sweden. The scale bars in pictures a-c equal 1 mm. All in all, the jaw is about 5 mm long. (Credit: Image courtesy of Uppsala University) When we lose our milk teeth they are replaced by new permanent teeth growing out in exactly the same positions. This is an ancient part of our evolutionary heritage and an identifying characteristic of the largest living group of backboned animals. Now, an international team including two scientists from Uppsala University has uncovered ancient fossil fish jaws that cast light on the origin of this group and its unique dentition. Together with scientists from Spain, Germany and France, Professor Per Ahlberg and Assistant Professor Henning Blom at the Department of Physiology and Developmental Biology have been studying two of the earliest bony fishes found in Sweden and Germany, managing to show that they belong to the same group of vertebrates as ourselves, the Osteichthyes. Their findings are published in this week's Nature. The backboned animals or vertebrates comprise three main groups. The primitive lampreys and hagfishes have neither jaws nor teeth. The cartilaginous fishes or Chondrichthyes (sharks and rays) grow new teeth on the inner face of the jaw; these gradually move up to the jaw edge, row upon row, and push out the old worn teeth. The third and much bigger group, the Osteichthyes, includes both bony fishes and all land vertebrates. In nearly all osteichthyans teeth are shed one by one and replaced by new ones growing up in the same place. Osteichthyans also carry their teeth on special jaw bones - the dentary in the lower jaw, maxilla and premaxilla in the upper - that have no equivalents in other vertebrates. Although the Osteichthyes are a big and important group, we know little about their origin. Their fossil record goes back to early bony fishes some 416 million years ago, but then it cuts out abruptly. However, in rocks of the Silurian period (some 420 million years ago) are found fossils of two fishes, Andreolepis from Gotland in Sweden and Lophosteus from Estonia and Germany, that could be very primitive osteichthyans. ”The problem is that until now no complete specimens have been discovered, only hundreds of scales and small bone fragments. Some researchers have denied that these fossils are anything to do with osteichthyans,” says Per Ahlberg. Now, the discovery of two jaw bones, a dentary from Andreolepis and a maxilla from Lophosteus, settles the identity of these fishes once and for all: they are the earliest known osteichthyans. Curiously, however, the teeth on these bones are not quite arranged in the osteichthyan fashion. Several rows are present, and it appears that new teeth were added along the inner edge of the jaw without the old teeth being shed. In some respects this is more like a shark dentition - not the modern kind, but the sort seen in the earliest fossil sharks. ”This suggests that Andreolepis and Lophosteus belong to the stem group, or common ancestral stock, of the osteichthyans, and also hints that the superficially very different dentitions of sharks and osteichthyans may ultimately be derived from the same ancestral pattern,”says Per Ahlberg. Andreolepis and Lophosteus may thus help us to understand how the first osteichthyans, our own remote ancestors, evolved from more primitive vertebrates. Free fish for thousands Fishupdate.com August 13 THOUSANDS of people were treated to a free fish feast at the weekend - everything from cod and haddock to salmon and prawns. The only snag was that anyone in Britain who wanted to take up the offer had to fly hundreds of miles north to Iceland. The fishing port of Dalvik, on Iceland's most northerly coast, which has a population of just 2,200 people, swept aside concerns over new fishing quotas to celebrate Fish Day on Saturday when local processors and townsfolk invited anyone who could get there to a seafood buffet totally free of charge. The goal of festival is bring people together to have a good time while enjoying the harvest of the sea without spending a single krona. Officially called The Great Fish Day, this celebrated event is an annual summer festival in Dalvíkurbyggð (to give the port its full name) held on the first or the second Saturday in August. The Great Fish Day has been such a successful event that during the first six years more than 130,000 people have taken part in this gourmet village feast. While most visitors are Icelandic,The Great Fish Day now attracts an increasing number of tourists from Britain and Europe. Dalvik is a typical Icelandic fishing port where most people are totally dependent on fishing and processing. But thanks to its spectacular mountain scenery it also an increasingly popular tourists area. As anglers age, fishing industry targets kids Arizona Republican - USA August 11 Long a favorite American outdoor activity, fishing has been slipping in popularity. You can see a trend in the mostly older men who line the lagoon near Chicago's Lincoln Park with rod and reel. Fishing sales nationwide have stagnated, according to the results of a U.S. Fish and Wildlife Service survey released in May. The survey, conducted every five years, found that U.S. anglers spent $40.6 billion last year. That total was similar to 2001's but down 16 percent from 1996s. The recreational fishing industry is using promotions and fishing clinics to draw youngsters. The Recreational Boating and Fishing Foundation has four initiatives under way: signing up youths for fishing programs; getting states to send license-renewal notices and to recruit anglers more actively; a collaborative campaign for the boating and fishing industries; and its year-old Anglers Legacy program, designed to mobilize anglers to take someone fishing. "Living Fossil" Fish Making Last Stand in China By Stefan Lovgren National Geographic News August 15 It's known as the "mother species" and the "panda under the water." Yet the nickname that most aptly describes the Chinese sturgeon, a giant fish that's been around since the age of the dinosaurs, may be "living fossil." Now conservationists are locked in a race against time to save this ancient river titan from extinction. Adult sturgeons, which can measure up to 4 meters (13 feet) in length and weigh 1,000 pounds (450 kilograms), migrate from the East China Sea into the Yangtze River to spawn. But the Yangtze's deteriorating environment and increased shipping traffic have taken their toll on the mammoth fish. Thirty years ago there were 2,000 spawning Chinese sturgeons in the Yangtze River every year. Now that number is down to several hundred. There may be only a thousand of the animals left in the river, said Wei Qiwei, a lead researcher at the Yangtze River Fisheries Research Institute in Jingzhou Wei and other scientists hope to reverse the trend by breeding sturgeons in captivity and putting them back into the river before the species disappears the wild. "The Chinese sturgeon is very precious to us," Wei said. "I don't want it to disappear on my watch." Sexual Maturity Wei's institute operates a breeding base tucked into a sleepy farming community outside Jingzhou. A slogan on a wall greeting visitors reads, "Love the Chinese Sturgeon, Our National Treasure." Inside, a hatchery facility the size of two football fields contains rows and rows of tanks holding sturgeons in varying stages of development, from larvae to one-year-old fish. Sexually mature sturgeons taken from the wild are kept at the hatchery to provide eggs for breeding. "The short-term goal is to preserve the fish in captivity, but the long-term goal is to preserve the fish in the river as part of the ecosystem," Wei said. To do that, scientists want to keep some of the newly hatched sturgeons in captivity until they are sexually mature before releasing them into the wild. But the reproductive capacity of the fish is poor; it takes more than ten years for the Chinese sturgeon to begin spawning. It will take at least another five years for the oldest fish at the hatchery, which are kept in holding tanks outside, to reach sexual maturity, the scientists estimate. "The critical issue for us is to make brood stock [from the fish taken from the wild] and then to release them again," said Zeng Lingbing, director of the institute's Fish Pathology Laboratory. "But we have not come full circle yet, so we don't know if this will be possible." Boat Traffic Fisheries biologist Zeb Hogan heads the National Geographic Society's Megafishes Project, a three-year program to document the world's largest freshwater fishes. Hogan recently visited the hatchery and said Wei's breeding program could help offset the many threats now facing the Chinese sturgeon in its native waters. "This breeding program is like an insurance policy to make sure this ancient fish does not disappear," said Hogan, standing waist deep in the green waters of a holding tank with a seven-foot (two-meter) sturgeon in his grip. The fish can grow twice that size, but no sturgeons that big have been seen in the Yangtze in the past 20 years, Wei explained. The Chinese sturgeon moves from seawater to fresh water to spawn. It has the longest migration of any sturgeon in the world and once migrated more than 2,000 miles (3,500 kilometers) up the Yangtze. That was before the Ghezouba Dam was built on the Yangtze River in the early 1980s, cutting off the sturgeon's migratory path, just as it did for the critically endangered Chinese paddlefish. All of the sturgeon's original spawning grounds were located upstream from the dam, Wei explained. "There used to be spawning grounds totaling more than 600 kilometers [375 miles] in the river," Wei said. "Now there is less than 30 kilometers [19 miles]." Increasing boat traffic on the Yangtze is a major threat to the sturgeon, which frequently swims near the surface. Every year, about ten Chinese sturgeons are killed by boat propellers. The sturgeon is also highly sensitive to increased noise on the river caused by growing traffic. In addition, Wei speculates that worsening water contamination from industrial runoff and other sources may be causing sturgeons to change their sex. "After 1995 the ratio of male to female has totally changed," he said. "It used to be one to one, but now there may be up to ten females for every one male." Habitat Restoration In addition to restocking the river with fish, Wei is also trying to find ways to create artificial spawning grounds in the Yangtze River. "Habitat restoration is another way to save the species," he said. Hogan, who is a National Geographic Emerging Explorer, says there is no umbrella solution for saving megafishes like the Chinese sturgeon. "If we look at rivers around the world, we see all kinds of problems—habitat fragmentation from dams, pollution, invasive species, overfishing," he said. "There are a lot of threats to large-bodied species of fish, and we have to look at each river separately to find the best way to save these amazing creatures." Flattieman.
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Thanks, mate. As you've probably noticed, I'm still really busy and don't have a lot of time for FR, but it is good to be posting the news regularly at least . Flattieman.
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Hi Raiders, Woah! I haven't made a post in ages! I've been really busy lately, but I've got a break over this weekend when I can hopefully catch up on all the posts I've missed! Hmm... I'll have a look in the Aquarium first... Enjoy the news! Giant fish tales could well be true Research suggests harvesting large fish help what's left become giant By Dave Mosher MSNBC, USA July 30 Three Redfin (Perca fluviatilis) of approximately equal age. The large individuals are "giant cannibals," which can occur if adults are over-fished. Anglers all have tales about the one that got away, the fish of legendary size that stripped the line from the reel. A new study suggests why that there might indeed be giants and offers an explanation for how they grow so huge. Turns out fishermen themselves can be responsible for the monsters. If a lake or pond is overfished, and a lot of the big ones are caught, the situation is ripe for oversized freaks to develop, according to a new computer model. The research suggests that harvesting only large fish knocks out the food competition for the remaining adults, allowing the adults to gorge on smaller fish and inflate to gigantic proportions. The effect is strongest for fish prone to cannibalizing their own. A Eurasian perch growing in such a situation, for example, can become more than four times as big as an adult fish the same age in a body of water not heavily fished. "The destabilization of a cannibalistic population can induce the growth of 'cannibalistic giants,'" scientists write in the August edition of the American Naturalist. Further, the population becomes less stable and more susceptible to crashing into extinction, especially as the rate of fishing increases. The giants were not found to develop in the virtual populations spared from harvesting. The effect also applies to fish species that are not cannibals, but it is less pronounced and does not tend to push the population toward extinction, the computer model suggests. There could be a useful lesson for fish farmers. The model accounted for a range of factors, from food availability to reproductive rates and digestion time. When the researchers over-harvested small fish, cannibalistic giants were not produced, but non-cannibalistic fish grew bigger, faster — a technique that fish farms could use to grow market-ready crops more quickly. The work was led by Tobias van Kooten of Umea University, in Umea, Sweden. Jaws, Teeth of Earliest Bony Fish Discovered By John Roach National Geographic News August 1 Fossils of sardine-size fish that swam in ancient oceans are the earliest examples of vertebrates with teeth that grow from their jawbones, according to new a new study. The fish, which lived 420 million years ago, are a "very modest" beginning for the jaw-and-tooth pattern widespread in nature today, said study co-author Philippe Janvier, a paleontologist at the National Museum of Natural History in Paris, France. "It's really the first evidence that we have of the earliest bony fishes—the earliest ancestors of all the fishes that have the[ir] bones and teeth implanted in the bones of the jaw," Janvier said. Modern bony fish such as cod, herring, and coelacanths have this tooth arrangement. So do tetrapods—four-limbed creatures such as frogs, crocodiles, and humans, which are all descendants of bony fishes. When a bony fish or a tetrapod loses a tooth, a new one grows from the bone below the void, whereas other jawed vertebrates, such as sharks, have teeth that grow from inside their gums. Sharks have skeletons of cartilage instead of bone. Shark teeth are lined up in "families." New teeth grow at the inner end of their respective tooth family, and old teeth fall off at the end of an inside-out progression—similar to a conveyor belt. Though fossil representatives of the earliest members of each of these living groups are well known, the earliest stages of jawed vertebrate evolution presents a fuzzier picture. The new fossils help clarify these questions, Janvier said. Transition Fossils The researchers discovered the telltale bony fish fossils among fragments collected on the Swedish island of Gotland in the Baltic Sea. Other fragments came from boulders carried to Germany by glaciers a few million years ago. Some of the fossils belong to the species Andreolepis hedei and others to Lophosteus superbus, fish previously identified by scale and head bone specimens. Whether they were truly bony fish or more like sharks was an open question, however. Two of the new fossils suggest a direct link to bony fish: tooth-bearing jawbones. What's more, the bones show a tooth pattern that is in between the tooth rows of sharks and bony fishes. Though these ancient bony fish teeth grew from a bone, old teeth remained attached to the bone. New, larger teeth grew at the inner end of each tooth file. "It shows a sort of transition between the shark condition and the bony fish condition," Janvier said. Within 20 million years after Andreolepis hedei and Lophosteus superbus lived, the first bony fish with much larger teeth characteristic of modern bony fish and tetrapods appear in the fossil record. This was during the Devonian period, 416 to 359 million years ago. "That's very important because it allowed the bony fishes to become predators," Janvier said. Sharks also existed in the Devonian, but they were "humble compared to the bony fishes," he said. The first bony fishes probably ruled the seas, rather than sharks, because the bony fishes' teeth lasted a longer time in the jaw. "Then, later on, the sharks ... became much larger and big predators," Janvier added. The study appears in tomorrow's issue of the journal Nature. Sorting Characteristics Michael Coates, a biologist at the University of Chicago in Illinois who studies early vertebrate evolution, was not part of the research team. He said the discovery of rare fossils like the ancient bony fish allows scientists to sort general, primitive characteristics of all jawed vertebrates from the more specialized features that distinguish sharks from bony fishes. The new study, he noted, clearly shows that Andreolepis and Lophosteus are bony fishes, but their tooth pattern raises a question about what makes a shark a shark. "Growing teeth in this serial manner around the jaw margin—which once upon a time looked like it was unique to sharks—now looks like it is a general system." Marine census details bluefin tuna decline Science Daily August 8 Scientists involved with the Census of Marine Life project have detailed the collapse of the bluefin tuna population off northern Europe. The research shows before World War I, Atlantic bluefins were rarely captured and even coastal sightings were exciting events. One bluefin measuring nearly 9 feet in length washed ashore in Germany in 1903. Those captured during the 1920s weighed as much as 1,550 pounds. After World War I, burgeoning quantities of tuna were caught. Major tuna fishing countries at the time -- such as Norway, Denmark, Sweden and Germany -- that recorded virtually no bluefin landings in 1910, reported nearly 5,500 tons by 1949. Scientists said such booming catches helped strip the Atlantic bluefin population in a very short time, with the species virtually disappearing during the early 1960s. The Census of Marine Life, based in Washington, is a global network of researchers in more than 80 nations engaged in a 10-year initiative to assess and explain the diversity, distribution, and abundance of marine life in the oceans. The network will release the first Census of Marine Life in 2010. The bluefin study is to appear in a special issue of the journal Fisheries Research. Fishing as a Contact Sport In Missouri, Catfish Grabbers Fight Fish and the Law By Jung H. Song and John Berman ABC News, USA July 29 ABC News correspondent John Berman holds a catfish. Missouri has banned fishing with your hands, also called noodling, on the cusp of the third noodling season. In the wild, wild Midwest, people who call themselves "noodlers" are catching massive catfish with their bare hands, using their own fingers and toes as bait. A seasoned "noodler" from Missouri, Howard Ramsey, proudly displays his scarred arms and digits, called "river rash" by insiders. "Yep, that's right, " he beams, "You gotta bleed." Noodling, which began with Native Americans, is the art of catching catfish with your bare hands. People like Howard Ramsey have done it for years without rod, hook or bait. Instead, they quietly grope the dark undersides of rocks or stumps in riverbanks, where catfish nest, until they feel the sandpaper-like teeth of catfish clamp down on their hands. Then, the noodler grips the jaws and triumphantly yanks the writhing fish to the surface. Ideally, that is. Sometimes, noodlers poking around the mossy, underwater crevices are also vulnerable to the painful bites of snapping turtles, snakes and beavers that may hole up in abandoned catfish nests. Noodling old-timer Ramsey quipped to ABC News' John Berman, "Webster's [dictionary] describes a noodle as 'a crazy person.' Just about anybody you talk to thinks you got to be crazy to do this." The idea of noodling may be laughable, but hand fishing enthusiasts say it's usually a fair fight. Fish can weigh up to 100 pounds, and many say what they like most about the sport is meeting the fish on its own turf and terms. Banned since 1919 for disturbing the natural food chain, noodling came back to Missouri two years ago after Ramsey and the fishing fanatics of "Noodlers Anonymous" fought for the right to hand fish on a trial basis for five years. During a six-week annual season, noodlers could nab up to five fish per day in three of the state's rivers. Their hook-and-line counterparts are allowed a daily catch of 20 fish, 365 days a year. But this summer, right on the cusp of the third legal noodling season, the Missouri Department of Conservation banned hand fishing once again. The Department said 646 catfish had been caught even before the noodling season began, and fisheries division chief Steve Eder reported that scientists had found higher-than-expected mortality rates among the state's catfish. Noodling is legal in at least thirteen Midwestern and Southeastern states, including Louisiana, Mississippi and, recently, Georgia. The greatest homage to the sport, however, takes place in Nigeria at the Argungu Festival, where 10,000 fishermen jump into opaque, coffee-colored streams to wrestle giant freshwater perch. Though Missourian noodlers claim they are being singled out, a Department of Conservation FAQ sheet explains that hand fishing targets the largest of the breeding fish, as well as their nests. Snatching a parent may leave thousands of catfish eggs vulnerable to predators. In response, desperate noodlers have offered to cut down their bounty to just five catfish per season, significantly reduced from their previous quota of five per day -- but the Missouri Department of Conservation just isn't biting. Noodlers have vowed to take their case to the state legislature. Fish bans raise poison risk By Selina Mitchell and Lauren Wilson The Australian August 4 The protection of Australia's fisheries is pushing seafood imports to record levels, driving overfishing in other countries and exposing consumers to unacceptable levels of antibiotics and other contaminants. Marine biologist Walter Starck said Australians were being forced to consume lower quality seafood imports, many from seriously depleted fisheries, even though Australia had a relative abundance in some species that was being underutilised. Dr Starck's warning comes amid increasing concerns about contamination of imported seafood products. Federal Fisheries Minister Peter McGauran revealed this week that tests conducted by Australia's quarantine watchdog had found small residues of banned antibiotics in one-third of the samples of prawns, fish, crabs and eels from China, Indonesia, Vietnam and Thailand. Amid fears that contaminated seafood could generate a new breed of antibiotic-resistant superbugs, the federal Government has promised to strengthen the testing of imported produce. But it has agreed only to add more antibiotics to the list of substances that are tested, rather than increase the actual amount of testing of imported fish. Just 5per cent of seafood imported to Australia will be checked for banned antibiotics and pesticides, despite the test findings. Consumer concerns about the imported seafood follow recent revelations about dangerous substances in imports of manufactured goods. Toymaker Mattel recalled 24 Fisher-Price character toys this week after they were found to contain potentially harmful levels of lead in the surface paint applied during the manufacturing process in China. And two brands of Chinese blankets were recalled nationally last month after they were found to contain high levels of carcinogenic chemicals. About 70 per cent of Australia's annual seafood consumption is imported after a long-running program of cutting the national fishing fleet. About one-third of commercial fishermen handed their licences back last year after a buyback cut 550 permits from the nation's 1600 commercial fishing licences. Australian fisheries are widely regarded as well managed, with the buyback considered necessary to ensure the fishing industry is sustainable. But Dr Starck said while certain species were clearly endangered and needed to be tightly protected, the current scale of regulation in Australian fisheries was focused on the unqualified conservation of marine environments rather than the sustainable management of fish stocks. He said it was now costing taxpayers $100,000 each year to manage each boat in the national fleet, even though Australia had the largest fishery per capita in the world. "The idea that our fisheries are in danger of overfishing as a blanket statement is ridiculous," he said. "If we want to import all of our fish, we can do that and that is basically what we are doing. If we applied the same rules to our agriculture and grazing, we'd have to close them down." Australia imported $1.03 billion worth of edible fish and seafood in 2005-06 -- up from $905million in 2003-04. The fastest growth was in products from Vietnam and China, which with Thailand now account for more than half of total seafood imports. Despite the recent discovery of antibiotics in imported seafood, Mr McGauran has moved to assure people of its safety. He said while the residues detected were at low levels and did not represent a food safety issue, there would be extra testing to give consumers greater confidence in supplies. In June, the US Food and Drug Administration imposed increased testing on Chinese farm-raised seafood -- including prawns, basa (Vietnamese catfish) and eels -- after finding produce repeatedly contaminated with banned antibiotics. The Australian Government introduced random testing of 5per cent of imports in 2001. But Labor has been pushing for more widespread testing, covering a greater range of chemicals and antibiotics. The Australian Quarantine and Inspection Service surveyed 100 samples of imported fish, crabs, eels and prawns for chemical residues from April last year to March this year. The samples were screened against 39 antimicrobial and 49 pesticide compounds. There were no pesticide residues detected but 14 antimicrobial chemicals were detected at low levels. The chemicals belong to the sulphonamides, tetracyclines, malachite green, penicillin, quinolones, fluoroquinolones and phenicols antimicrobial chemical groups. The National Health and Medical Research Council is investigating the issue of microbial resistance, but will not report for several months. Peter Collignon, director of microbiology and infectious diseases at the Australian National University medical school, said the test results were worrying. "What this means is antibiotics were used in the production of those fish or prawns. That means superbugs can develop and they can remain on the animal and come across to people and cause problems," he told ABC Radio. Of the 20 fish retailers contacted by The Weekend Australian yesterday, none believed strengthened testing measures would benefit Australia's seafood industry. All food imported and sold locally must be labelled with its country of origin, but consumer group Choice yesterday questioned whether the rule on labelling was being properly policed. Choice recommended that if people were worried about their safety, they should ask where the seafood had come from. Antibiotics can be used in production but all traces should be gone by the time the seafood is harvested for market. AQIS spokesman Carson Creagh said the test results released by the minister this week had been passed on to Food Standards Australia New Zealand and the national Health and Medical Research Council for expert advice. The Australian fishing industry blames an unfair playing field, including tight government regulation, for forcing local producers to charge more for their safe, wild-caught seafood while competitors intensively farm fish in other countries. The use of antibiotics overseas was a concern, but many consumers could not afford higher prices for local fish. "The quality of the product going out of the country is strictly monitored but the product coming in is not so carefully watched," Western Australia's Fishing Industry Council chief executive Graeme Stewart said yesterday. But Harry Peters, the president of the Australian Seafood Industry Import Association, said imported produce was subject to rigorous testing. He said Australia did not have a problem with contaminated imported seafood: "Australia has always had a zero-tolerance policy when it comes to ensuring our imported seafood isn't affected." China is struggling to contain fears that some of its exporters have cut corners, making their products unsafe. A recent report by China's Administration of Quality Supervision, Inspection and Quarantine claims more than 99 per cent of Chinese food exports met all criteria. But the Government is responding to fears about the other 1 per cent -- especially because of fast-growing anxiety within China about food and drug safety. The minister in charge of food safety, Li Changjiang, said China was "addressing the fundamental causes" behind the range of problems with exports, which have included toothpaste containing antifreeze and snack foods with salmonella. He admitted that US complaints about farmed fish and shellfish containing banned antibiotics were correct, and that in some cases seafood had even been exported as antibiotics -- which the fish contained -- to evade inspection. 'Living Fossil' Fish Hooked in Asia By Ronan Bourhis Discovery Channel July 31 Two months ago an Indonesian fisherman caught a fish so exceptional that an international team of scientists rushed there to investigate. French experts equipped with sonar and GPS asked the fisherman, Justinus Lahama, to reconstruct in his dugout canoe,exactly what it was he did to catch a rare coelacanth, an awkward-swimming species among the world's oldest. "I very quickly unrolled the usual trawl line with three hooks, about 110 yards long, and at the end of three minutes, I felt a large catch," Lahama recounted. After 30 minutes of effort under the searing tropical sun, he finally saw a fish swishing at a depth of about 65 feet. He thought he was dreaming, he said, when he saw the creature at the end of his line. "It was an enormous fish. It had phosphorescent green eyes and legs. If I had pulled it up during the night, I would have been afraid and I would have thrown it back in," he exclaims. After spending 30 minutes out of water, the fish, still alive, was placed in a netted pool in front of a restaurant at the edge of the sea. It survived for 17 hours. Coelacanths, closely related to lungfish, usually live at depths of 656-3,200 feet. They can grow up to 6.5 feet in length and weigh as much as 200 pounds. Lahama, 48, has fished since he was 10-years-old, like his father and his grandfather before him. But he was unlikely to have ever run into this "living fossil" species, as scientists have dubbed the enigmatic fish. Lahama's catch, weighing 110 pounds, was only the second ever captured alive in Asia. The first was caught in 1998, also off the Indonesian coastal city of Manado. That catch astonished ichtyologists, who until then had been convinced that the last coelacanths were found only off eastern Africa, mainly in the Comoros archipelago. They had been thought to have died out around the time dinosaurs became extinct, until one was found there in 1938. Their fossil records date back more than 360 million years and suggest that the fish has changed little over that period. Can Shortnose Sturgeon Fish Survive? Science Daily August 7 Dwindling numbers of shortnose sturgeon in Georgia's blackwater Ogeechee River system have prompted an effort to quantify the causes and prioritize recovery efforts. Yetta Jager and colleagues at Oak Ridge National Laboratory are conducting a population viability analysis, which will provide a scientific basis for assessing cumulative and separate effects of factors thought to be impacting the shortnose sturgeon population. These factors include siltation of spawning areas, degradation of water quality in summer due to upstream agriculture, urban development and military land management, atmospheric mercury and introduction of saline water introduction through rice canals. While 19 distinct populations of shortnose sturgeon have been identified in coastal rivers, only two southern populations are thought to be viable. The Ogeechee population has fewer than 500 fish. Jager is working in cooperation with field efforts conducted by Fort Stewart and Doug Peterson at the University of Georgia in this three-year project, which is funded through the Strategic Environmental Research and Development Program. Fish stunned during flood rescue BBC News July 31 A current of electricity is passed through the water Thousands of fish stranded by floods are being stunned with electricity as part of efforts to rescue them. The fish have been trapped at the flooded racecourse in Worcester. The Environment Agency said the oxygen levels have been dropping out of the water quickly so the fish would die if they were not helped now. Electricity is passed through the water before the fish are collected in nets and tanks to be stored until they can be put back in the water later. Carp, bream and eel are among the types found so far. 'More adventurous' David Throup, from the Environment Agency, said it was a race against time. He said: "It's the second time it's happened with the summer floods. "What usually happens in the winter is the fish are quite torpid. They're quite slow and they tend to roll back in the river when the waters go down. "In the summer they're more adventurous and they're looking for somewhere to spawn, somewhere to feed, so they go out across the flood plain." He said the agency would try to deal with the larger fish on Tuesday evening and intended to return on Wednesday to help the smaller fish. Thief battered in fish shop IOL - South Africa July 30 A man who attempted to rob an Australian fish and chips shop found himself on the losing side when the angry shop owner threw fish batter and hot oil at him. "The hot oil missed but the batter hit the offender and he fled empty handed," South Australian police said in a statement. Police said the attempted armed robbery happened on Thursday evening at the quiet seaside retirement town of Victor Harbour, near the South Australian state capital of Adelaide. Police were checking local hospitals in case the man was injured. Flattieman.
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Nice feed of flatties there, Robee! Good size to them, in general - do you work your plastics whilst drifting or use the movement of the boat? I tend to always work mine, but some people prefer the "set-and-forget" approach whilst drifting. Flattieman.
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Man dies of wounds after trying to use dynamite to fish near Sidon harbor By Mohammed Zaatari The Daily Star (Lebanon) July 24 A Lebanese fisherman was killed next to Sidon's harbor while using dynamite to fish during the weekend. Said Maoush, 60, was trying to throw a stick of dynamite into the water when the stick exploded. The fisherman's left arm was blown into the sea and his face was burned. Maoush died of his wounds soon after he was rushed to a nearby hospital. Blast or dynamite fishing became very popular in Lebanon during the years of the 1975-1989 Civil War. Following the conflict, blast fishing was prohibited by the government. The Coast Guard conducts extensive patrols to deter blast fishing, but a number of fishermen nevertheless still use the technique, because of its efficiency in killing large numbers of fish, despite the potentially deadly outcome of the practice. Environmental activist Mohammad Sarji told The Daily Star that roughly 12 people per month fall victim to the practice. Dynamite fishing is easy and cheap, as fishermen use dynamite or homemade bombs made from locally available materials. Fish are killed by the shock of the blast, and the fishermen later collect the dead fish from the water's surface. Blast fishing is illegal in many waterways around the world and is also prohibited by a number of religions, such as Islam. "The explosions indiscriminately kill large numbers of fish and other marine organisms in the vicinity, and a number of fishermen are killed or severely wounded when using primitive bombs and dynamite sticks," Sarji said. Sarji added that explosions were particularly harmful to fish eggs and the reproduction cycles of fish and marine organisms. Sarji said the Internal Security Forces had recently arrested fishermen using dynamite along the southern coast from the town of Sarafand to the border town of Naqoura. "Let us hope this step will eradicate the use of dynamite in fishing," he added. One fisherman, who lost an arm some 30 years ago while fishing with sticks of dynamite, agreed to share his experience. "I warn my children, who also work as fishermen, not to make use of dynamite fishing, as rewarding as it might seem," said the fisherman, who asked to be identified as Hilal. China's Giant River Fish, the World's Largest, Feared Extinct By Stefan Lovgren National Geographic July 26 If the world's largest freshwater fish still exists, Wei Qiwei will be there to save it. "I believe it's out there," said Wei, as he scanned the murky Yangtze River from his sleek, 63-foot (19-meter) rescue vessel. Wei is one of China's foremost experts on the Chinese paddlefish, a leviathan that reportedly can grow 23 feet (7 meters) long and weigh half a ton. But the odds of finding even a single one of the aquatic giants may be steadily diminishing. No adult Chinese paddlefish have been caught in the Yangtze River by fishers since 2003. Even more worrisome, no young paddlefish have been seen since 1995. "When you don't see juveniles, we think maybe there's no spawning," said Wei, who heads a research laboratory at the Yangtze River Fisheries Research Institute in Jingzhou. He and other experts fear that even if individual paddlefish are found in the Yangtze, the species itself, if unable to reproduce, could be on an irreversible path to extinction. Spawning Ground The Chinese paddlefish is also known as the elephant fish, because its long snout resembles an elephant's trunk. The predators feed on other fish, as well as small amounts of crab and crayfish. Prized for their rich, plentiful meat, the giant animals are said to have been commonly offered as gifts to the Chinese emperor during imperial times. In the 1970s hundreds of paddlefish were caught each year by fishers on the Yangtze River. Then, in the 1980s, the population dropped dramatically, Wei said. The culprit for that loss can be found by taking a 20-minute boat ride up the river from the city of Yichang to the giant Gehzouba hydroelectric dam. The dam, completed in 1983, divided the Yangtze River into two sections, cutting off the migratory route of the paddlefish. "The paddlefish travel long distances, from their forage grounds in the middle and lower part of the Yangtze River—and sometimes the coastal waters—to their spawning grounds in the upper river," Wei said. "The dam separated the feeding area from the spawning ground." The spawning process for paddlefish is particularly sensitive because females do not become sexually mature until they are seven or eight years old, he added. The newly built Three Gorges Dam, the largest hydroelectric dam in the world, which sits 30 miles (48 kilometers) upriver from the Gezhouba Dam, has further reduced paddlefish habitat, Wei said. Two more dams are now being planned for the upper reaches of the Yangtze River. Last Animal Caught Fisheries biologist Zeb Hogan was also aboard Wei's boat on his recent ride up the Yangtze. Hogan heads the National Geographic Society's Megafishes Project, a three-year program to assess the conservation status of the world's largest freshwater fishes. The plight of the Chinese paddlefish underscores the urgent need to protect the river giants, said Hogan, who is a National Geographic Emerging Explorer. "Here is what is perhaps the world's largest freshwater fish, and it's close to extinction," he said. An 11-foot (3.3-meter) paddlefish was caught by fishers in December 2002, Wei pointed out. It died after 29 days in captivity. The following month, a 12-foot (3.5-meter) paddlefish was caught in Yibin in the upper Yangtze. Fisheries law enforcement officials immediately contacted Wei. During the eight hours it took him and his crew to travel to Yibin, Wei gave suggestions to officials on how to handle the fish, which survived. Before it was released back into the river, Wei planted a location transmitter on the paddlefish. Wei has since lost the signal, but he believes this fish is still alive. "These fish can live for maybe 50 years," he said. "I'm sure it's still there." Underwater Caves Wei and Hogan have agreed to embark on a joint expedition next year to look for Chinese paddlefish. Wei believes the upper Yangtze provides a possible last refuge for the fish and that there might be up to a dozen individuals left. "That area has many deep pools and underwater caves where the fish can hide," he said. Wei vowed not to retire until he finds a paddlefish. "I have another 20 years to go," he said. "I'm not giving up that easily." Gardening Fish "Domesticate" Crops of Algae By Helen Scales National Geographic July 23 Damselfish can appear quite contrary to species that wander into their gardens of algae by aggressively chasing off larger fish and even nipping at human divers. But for some damselfish species, protecting their "crop" is a matter of survival for both the fish and the algae, according to recent research. The dusky farmerfish has developed a co-dependent relationship with a species of the red algae Polysiphonia. Both creatures are found on coral reefs in the Ryukyu archipelago, a scattering of islands that stretches between southern Japan and Taiwan. "Not only do the fish rely on the algae as a source of food, but the algae only survive well if they are farmed," said Hiroki Hata, a marine biologist from Kyoto University in Japan. "We saw dusky farmerfish feeding exclusively inside their farms, which are dominated by a single type of algae that we called 'Polysiphonia species one,'" Hata said. Scouring the reefs also revealed that Polysiphonia species one grows only inside the gardens of dusky farmerfish. In total, Hata and colleagues identified four new Polysiphonia species that have adapted to rely on particular types of damselfish. "Life inside the damselfish gardens is so good for the algae that they seem to have come to depend on being farmed," Hata said. Guarding and Weeding Damselfish are among the handful of animals—including humans, ants, and salt-marsh snails—that are known to cultivate beneficial crops. Although they are relatively tiny—on average about 6 inches (15 centimeters) long—damselfish seem to tend their gardens with zeal. Unwanted sea urchins and starfish are ejected from the farms, and unpalatable algae are meticulously weeded out to promote lush turfs of the preferred species. In a study that appeared last October in the journal Biology Letters, Hata and colleagues described what happens when the damselfish are removed from their plots. The team built cages to set around the actual gardens and thus control what could get in. If all herbivores are kept out—including the damselfish—within a week the Polysiphonia gardens become completely overrun by other species of algae. "When only the damselfish are removed," Hata said, "it takes just a couple of days for other grazing fish to move in and obliterate all the algae growing inside the gardens." Spreading the Seeds Nancy Knowlton is a marine biologist at the Scripps Institution of Oceanography in La Jolla, California. Knowlton, Hata, and colleagues plan to study similar farming damselfish on the reefs of Panama later this year. One of the questions the team wants to examine, Knowlton said, is how the fish developed such a specialized relationship with the algae. Many kinds of farming animals practice vertical inheritance, in which they transfer some of their crops from established gardens to set up new colonies. But dusky farmerfish instead seem to establish new territories when waterborne spores or fragments of algae drift to new parts of the reef from nearby gardens. The fledgling plots can then flourish under the care of new damselfish. "There is no evidence that tiny larval damselfish would be able to transfer algae from their parental gardens to their own new territories," Knowlton said. "Without vertical inheritance it's unclear how the specific fish-algae relationships could come about." Meanwhile, Hata said, existing damselfish gardens face an uncertain future as global warming continues to negatively impact coral reefs. Although it is difficult to predict, he noted, increased sea temperatures could eventually lead to a breakdown of the relationship between fish and algae. "The damselfish depend on new coral skeletons to establish their gardens on," he said. "Without new coral growth, older skeletons will erode away and eventually could leave the damselfish with nowhere to cultivate algae." Male Stickleback Fish Masquerading In Murky Waters ScienceDaily July 22 Where humans lower water quality, poor quality stickleback male fish trick unsuspecting females. Finding a decent, honest mate is challenging enough without the added problem of reduced visibility caused by human-induced changes to the aquatic environment. Yet this is precisely the sort of dilemma female stickleback fish are facing in the Baltic Sea, according to a recent study published in the August issue of the American Naturalist by Dr. Bob Wong, an Australian researcher from Monash University, and his Scandinavian colleagues, Dr. Ulrika Candolin from the University of Uppsala and Dr. Kai Linstrom from the Åbo Akademi in Finland. An increase in nutrient input in the Baltic is compromising water clarity by promoting algal blooms. Dr. Wong and his colleagues were interested in finding out whether this, in turn, might lead to a break down in the honesty of sexual displays used by male sticklebacks to attract females. They did so by examining the courtship effort of good and poor condition males in the absence and presence of a rival male in both clear sea water and water rendered turbid by algae. "Under reduced visibility caused by the presence of algae, poor quality males are able to lie about their physical condition to unsuspecting females by displaying at a higher rate without the risk of attracting the wrath of rival males," says Dr. Wong. "Since poor condition males are also more likely to eat the eggs that they're suppose to be tending, this is bad news for females who rely on the honesty of male sexual displays to select mates with superior parental qualities." Catch-Release Angling Injures Fish By Jennifer Viegas Discovery News July 20 Catch and release fishing seems like a win win-situation, with recreational anglers experiencing the thrill of a catch, while their prey can, in theory, swim safely away. But that's not always the case, according to a new study that found fish, including sharks, may suffer so much trauma during the event that they could die shortly thereafter. The findings, which will be published in next month's Journal of Experimental Marine Biology and Ecology, primarily apply to hook and line anglers, since the catches of seine net users rarely died upon release. "Small sharks are susceptible to predation by larger sharks following release," lead author Sascha Danylchuk told Discovery News. Danylchuk, a researcher at the Cape Eleuthera Institute in the Bahamas, added that even if catches survive, they might be less able to reproduce or more susceptible to disease. Although the findings apply to sharks and other fish, Danylchuk and her team focused on bonefish, a tropical fish whose wariness and speed make it a sought-after target among recreational anglers. The scientists angled and landed 88 bonefish in Eleuthra, the Bahamas, with fly-fishing equipment. A second group of fish was caught using a seine net. Following releases, each fish was observed for up to one hour. Fish that experienced a loss of equilibrium, or an inability to swim away normally, were six times more likely to die than others. "When a loss of equilibrium has occurred, what we as anglers see is a fish rolls on its side or ends up nose diving to the bottom rather than swimming away with some vigor," Danylchuk said. She compared it to a person being asked to walk a straight line after having been spun around in a circle, or to a runner giving his all, "essentially what a fish is doing when it is being angled," and then not being able to walk very well afterwards because muscles are full of lactic acid. Like marathon runners, it is as though the caught fish "hits a wall." "Extensive exercise, in combination with air exposure, a hook wound and extensive handling all can play a role in loss of equilibrium," she said. During the study, predators, including lemon sharks and great barracuda, quickly nabbed the bonefish that experienced the equilibrium problem. The scientists think traumatized fish may even release stress chemicals, which function like a dinner bell to watchful predators. In an unrelated study, scientists at the New South Wales Department of Primary Industries are investigating ways to boost the survival rates of fish that are caught and then released by anglers. Preliminary findings suggest that a quick and easy technique can help to eliminate unnecessary deaths. "Simply cutting the line, rather than attempting to remove hooks swallowed by mulloway and yellowfin bream, increased their survival from 12 percent to more than 85 percent," said Matt Broadhurst, one of the researchers. Broadhurst and Danylchuk also recommend that catch and release fishermen should minimize air exposure, use landing nets without knotted mesh, use barbless hooks to help expedite hook removal, and avoid sunscreen and bug repellent on hands, since Danylchuk said, "these can affect the slime coating on fish." Trophy fish photos are still possible, she said, but fishermen must take care. "Make sure to get your shot all set up before taking the fish out of the water," she advised. "When you do take the fish out of the water, try holding your breath. When you need to breathe, the fish probably does too and it's time to put it back in the water." Flattieman.
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Hey, Raiders! Long time, no chat! Well... I attended the ISS as described in the last edition of Friday Fishy News - they were two of the best weeks of my life! Made heaps of awesome friends and learned a lot in the process - the social life really made it awesome, though! So much so that I've been to distracted by chatting on MSN to get back into the swing of things on FR! Anyway, I'll try to catch up on some of the posts I've missed (there's HEAPS) in time... In the meantime, here's the news!: Considering that I learned about climate change for two weeks, I think the next story is an apt choice to kick this edition off... Climate to put heat on fish stocks By Ewin Hannan The Australian July 9 CLIMATE change is likely to put significant pressure on the nation's fish stocks, with new CSIRO research identifying the eastern and southeast coastlines as the most vulnerable to warming temperatures. A new CSIRO climate change vulnerability index, to be launched today, finds coastal waters will warm by up to two degrees by 2030, encouraging fish to move south, threatening marine turtles, and potentially pushing box jellyfish down the east coast. Scientists said yesterday fishing stocks potentially faced a "double whammy" from the consequences of fishing and climate change. The climate change index, developed by CSIRO's Marine and Atmospheric Research Unit, considered seven large marine domains around Australia and determined their vulnerability to climate change based on five dimensions. These were biological, regional characteristics, climate change, fishing, and other stress factors caused by human activity. The index revealed that the eastern-central and southeast domains were the most vulnerable to the impact of climate change. The index predicts that sea surface temperatures around Australia will warm by 1-2C by 2030, and by up to 3C by 2070, with the greatest warming off southeastern Australia and the Tasman Sea. Anthony Richardson, a member of the CSIRO's Wealth from Oceans Flagship, said the advantage of the index was that it identified principal stress factors for each domain, and allowed the development of regional policies to tackle climate change. Dr Richardson said that as waters warmed along the east coast, fish and marine life would be encouraged to move south. He said scientists believed potentially fatal box jellyfish could move south from Queensland. "The east Australian current which flows south along the east coast will strengthen and take jellyfish further south," he said. "The conditions there will be warmer so they may do OK further south so that has implications for bathing." Dr Richardson said the impact of climate change would have potential significant consequences for the nation's fishing industry, with warm-water fish likely to move south, and cold-water fish also expected to retreat down the coast. "I think the fishing industry is starting to be concerned about the impact of climate change," he said. "They are fishing heavily, and the changing environmental considerations are all stresses in the future. Pressure from fishing and climate change represent a double whammy for the industry." Professional fisherman Rolf Norington has already seen a change in the species he catches over his 25 years in the industry. Now licensed to catch only prawns and squid, Mr Norington, from Brooklyn, north of Sydney, said that warmer currents sweeping down the coast from Queensland had brought the spawn of new species into Broken Bay. "With the 13 years of drought we have just faced, the Hawkesbury River system has had little flow and the saltiness of the water has allowed new species to grow and breed," he said as he prepared his boat, Australia Star, for this week's work. "If we are allowed to address the problems caused by drought and climate change, it will be nice, but we are being regulated out of existence and our markets are being taken by imported prawns and other seafood." Mr Norington said the existing conditions placed on prawntrawlers prevented them from taking any fish species with amateur fishing bag limits and also prevented them from working on weekends and public holidays. "We are always painted as the bad guys ... raping the fishing resource, but nothing could be further from the truth," he said. "It is our livelihood. Why would we destroy it?" Mr Norington, 41, said he and other professional fishermen were keen to work with government bodies and environmentalists to ensue that Australians could continue to enjoy fresh local seafood and not rely on frozen produce brought in from Asia. According to the CSIRO, the warming waters will also result in an increased number of female marine turtles being born, making it more difficult for the turtles to mate in the future. The index will be presented to the Australian Marine Science Association conference starting in Melbourne today. The conference will also consider research examining the impact of warming waters on climate change. The CSIRO's Elvira Poloczanska said fish on the east coast that were living on or near the sea bed had shifted southwards as coastal waters warmed. "The large giant kelp forests that are found fringing the coasts at spots in southern Australia support a myriad of fish and other animals," she said. "These cold-water seaweeds are at high risk in Australia from warming waters. Kelp forests on the east Tasmanian coast are already in decline as sea temperatures increase." and a similar story... Warming waters to drive fish south: CSIRO ABC News Online By Timothy McDonald July 9 A CSIRO study of the waters off the south-east coast of Australia reveals that they are warming up faster than anywhere else in the southern hemisphere. The scientists warn that these warmer waters will not only dramatically change the marine environment, but could devastate local fisheries. However fisherman from the area say they are not worried yet because they have just had their best catch in years. Steve Buckless, a fisherman from the NSW south coast, says this year's catch has been outstanding. "Just general trawl fish - which is flathead, ling, blue grenadine - most of those species are more abundant this year than they have been for the last seven or eight years," he said. "We're finding the catchability (sic) has increased incredibly this year." But the CSIRO study suggests that the good times will not last for ever, because the normally cool waters off the south-east of Australia are warming up. CSIRO marine biologist Dr Anthony Richardson says that could have a huge impact on marine life that thrives in cooler climates. "In the next century the greatest warming in the Southern Hemisphere will be off south-east Australia and in the Tasman Sea," he said. "That's likely to be about two to three degrees in the next 50 years and that's likely to have major impacts on fisheries and other forms of marine life. 'Vulnerable' The cooler waters off south-eastern Australia are rich in nutrients and support a diverse range of sea life. But Dr Richardson says the fish that live there could be vulnerable, because they need to stay within a relatively narrow band of temperatures in order to survive. He says if the waters warm up, subtropical fish will move in from the north and local species will retreat further south in search of a more comfortable climate. That is a problem because fish feed on nutrients that wash into the sea from a nearby landmass, and if they are pushed too far south they will run out of land. "One of the problems in Australia is that there is, if you like, a costal habitat," he said. "If you're a fish there's so only so far you can move south before you run out of landmass. "So that's of concern. "But there's also groups of species, like kelps for instance, that prefer cold, nutrient rich water and as that becomes less and less common in the future those sort of species, like kelp, are likely to do poorly. "There's a whole community that are found around kelp forests and the kelps in Tasmania, for instance, are already showing a decline. Commercial fishing Dr Richardson the warmer waters could also have a negative effect on commercial fishing, because they are not as productive. "It will also affect the productivity because the warm water and the east Australian current that runs south is likely to penetrate further south and that is low nutrient water," he said. Mr Buckless says global warming may have some long-term consequences for his business, but the drought has had a much larger impact over recent years. "I wouldn't argue with the theory that fish could move south, but it's also got a lot to do with the drought effects we've been seeing currently," he said. "I wouldn't argue that over a long period of time computer models are going to show the warm waters are pushing further south, but ... we're certainly not seeing that this year." Excavation begins on Darling River to give fish new homes ABC Rural July 19 Work has started in the lower Darling River to provide new homes for native fish. While for years fallen trees were removed from the river bed to make room for boats, they are now being replaced by authorities. Excavators have been called in to help winch the logs into selected parts of the river. The New South Wales Department of Primary Industries' Mark Neeson says a wide range of fish will benefit. "Murray Cod tend to like snags to use as a home site and also as a breeding site and the Golden Perch are often found around the snags because they not only shelter from them, but they also are able to feed on shrimp that graze on the algal films that grow on the timber," he said. Call for greater fish stocks protection ABC News Online July 19 The Western Australian fishing industry says urgent action is needed to stem the decline of scalefish stock. The WA Fishing Industry Council says dhufish and snapper stocks are particularly vulnerable. Council chief executive officer Graeme Stewart says the stocks need greater protection to ensure they do not become extinct. He says bag limits need to be tightened. "The precaution ... will prevail, that is to say we operate ... with a great deal of caution, it's very susceptible to, if not extinction, to certainly being fished to extremely low levels, to dangerously low levels," he said. Fish stocks surge not only indicator of estuary health ABC News Online July 9 Researchers are warning against using a surge in fish stocks in the Wilson Inlet, in southern Western Australia, to measure the estuary's health. A group of researchers from Murdoch University is conducting a two-year study looking at fish numbers and species in six south coast estuaries. The program includes tagging and releasing fish species, including black bream, king george whiting, herring, cobbler and mullet. Researcher Ben Chuwen says while the Wilson Inlet is in good health now, it could be facing a collapse in fish stocks, like the Peel Harvey Inlet did 20 years ago. "Looking at the data that we have so far, it certainly is looking very similar to what happened to the Peel Harvey [inlet] 20 or 25 odd years ago, so there's a lot of growth of algae and a lot of food and a lot of shelter for these species at the moment, but if we look to the future and perhaps something starts changing, we might indeed see a collapse," he said. Govt 'not testing' Chinese fish imports The Age July 13 The federal government does not test for contamination in imported Chinese fish despite US officials banning imports because of worries antibiotics are infiltrating the food chain. The US Food and Drug Administration (FDA) issued an alert on June 28 saying it would stop all Chinese farm-raised eel, catfish, basa, shrimp and dace at its border. FDA assistant commissioner David Acheson cited concerns over high levels of antibiotics in the seafood. Agriculture Minister Peter McGauran's office has not yet responded to questions on whether the Australian government is testing for the antibiotics, known as fluoroquinolones. But the Australian Quarantine and Inspection Service confirmed no testing for fluoroquinolones is done without a specific request from Food Standards Australia and New Zealand. "No, we don't do that test," a quarantine spokesman said. Labor has attacked Mr McGauran for failing to act on the US warning. "Australia does not screen for fluoroquinolones," Labor's agriculture spokesman Kerry O'Brien said in a statement. Senator O'Brien said the issue needed urgent attention. "This means urgently increasing testing frequency for the full range of potentially harmful contaminants including nitrofurans and fluoroquinolones." Microbiologist John Turnidge of Adelaide's Women's and Children's Hospital says the risks created by fluoroquinolones entering the food chain are great. The major concern, he said, was that if the antibiotics enter the food chain people will begin building up an immunity to fluoroquinolones, as has happened with other antibiotics. "The small amounts that might be in food could theoretically select for resistance in the bacteria that you and I carry in our guts," Professor Turnidge said. "For all of those reasons we would be very unhappy to see fluoroquinolones in the flesh of imported fish." Prof Turnidge said he was not aware of what, if any, monitoring for fluoroquinolones was done by the government. NT barramundi farm investigates fish feeding habits ABS Rural July 2 A barramundi farm in the Top End is investigating the sounds fish make when they are eating. Humpty Doo Barramundi's Bob Richardson says fish feeding is the most expensive part of the operation and is often dominated by more aggressive fish. Feed is also wasted because it is not distributed evenly. He says they are now piloting new technology which could improve feeding efficiency by more than 10 per cent. Maine studies effect of plastic, rubber lures on fish Boston Morning Sentinel July 4 UNITY, Maine --A marine biologist with the Maine Department of Inland Fisheries and Wildlife hopes that his study will help to determine the effects of plastic and rubber lures on fish that swallow them. Scuba divers and fisheries biologists have found these lures, made in a variety of shapes, sizes and colors, littering the bottoms of Maine's lakes and ponds following the growing popularity of bass fishing. But Russell Danner is more interested in what happens to them when they're ingested by fish. "We're just looking to see if it causes any health problems," Danner said. Danner's study could lead to legislation that would curtail the use of traditional, indigestible plastic lures. Since biodegradable artificial lures are already on the market, "they would be a good choice even now," he said. To study the lures' effects, Danner split 70 hatchery-raised brook trout into two groups, placed them in tanks at Unity College. Over 90 days, one group of fish was fed food, while the second group ate food spiked with soft plastic lures. The feeding portion of the study ended last week, when the fish were euthanized and Danner began a battery of tests. He was startled to find that fish were eating large pieces of lures that were remaining undigested in their stomachs. Slicing open a 9-inch trout in the laboratory, Danner discovered a 1-inch long piece of rubber worm in its belly. Later, a 9-inch plastic salamander popped out when Danner cut into a similar-sized fish. Because the fish were fed different colored lures each week, Danner will be able to learn how long the lures stay with the fish. Jim Chacko, the college's professor of aquaculture, discovered a difference even before the fish were euthanized. Holding a small can of food, he tossed a small handful into the tank with the healthy fish, which swarmed to the top to grab a piece. When food was tossed into the tank of fish that had consumed the lures, however, the fish slowly made their way to the top to nibble. "I think it's because their stomach is full so their reaction is very slow," Chacko said. Danner found an excess amount of green bile inside a number of fish, which is an indication the fish are not eating properly, he said. The fish were measured and weighed and a blood sample was taken to measure glucose levels, the ratio of red blood cells and blood protein. The readings, measurements, stomach and liver contents, and the fish themselves, will be compared to those provided by the pure food group to learn how the plastic lures effect the fish overall health. Coral Reef Fish Need Decades Or Longer To Recover Science Daily July 13 In the longest running study on how fish populations in coral reef systems recover from heavy exploitation, researchers from the Wildlife Conservation Society (WCS) and others have found that the fish can recover, but they need lots of time -- decades in some cases. With nearly continuous data spanning some 37 years from four national marine parks off the coast of Kenya which were closed to fishing at different times, the study found that commercially important species such as parrotfish, wrasses, and surgeonfish can take a quarter of a century to recover fully. More importantly, the ecological equilibrium needed for a healthy reef system, which relies on the interplay of many fish, invertebrate, and plant species, take even longer to achieve, and certainly longer than the length of the study. Most fish recovery studies are conducted with small data sets in short durations of time. "There's a pressing need for long-term studies on how fish communities in reef ecosystems rebuild when fishing is banned," said WCS researcher Dr. Tim McClanahan, the lead author of the study. "This study gives us some important insights in how the different fish species recover and how these communities affect the health of the reef as a whole." Specifically, the study examined the recovery rates of eight dominant fish families in Kenya's marine national parks between 1987 and 2005 using counts that measured fish diversity, size, and density. What the researchers found is that species diversity peaked and stabilized 10 years after a marine park was closed to fishing. The recovery rates of different families and species, however, occurred at different rates, partly as a result of competition for resources among different species. For instance, most parrotfish took some 10-20 years to recover, but then declined, perhaps as a result of competition from a variety of surgeonfish. A group of fish known as wrasses increased and then peaked in diversity and numbers after 10 years and then their abundance declined, perhaps as a result of competition with triggerfish for the same invertebrate prey. One species of triggerfish--the orange-lined triggerfish--became dominant in the parks with the longest fishing bans, actively excluding other competitors from territories. Triggerfish are important in another respect; they feed on sea urchins, which in turn feed on the reef-building algae on which the entire reef system depends. When fishing eliminates species that prey on sea urchins, the invertebrates can severely impact the entire system, so keeping sea urchins in check is vital to coral reefs. Overall, the time frame needed by surgeonfish and tangs, triggerfish, rabbitfish, and the coral-building algae to completely rebuild their populations to pre-fishing levels may exceed the length of the study."Decisions made by managers to close areas to fishing in an effort to save fish populations can be unpopular but necessary," added McClanahan. "What this study has shown us is that many fish populations take long periods of time to recover fully, and that permanent bans on fishing in some parks are necessary if we're to conserve healthy coral reef systems." The study appears in a recent edition of the journal Ecological Applications. East African Fishermen Catch Rare Ancient Fish FOX News July 16 ZANZIBAR, Tanzania — Fishermen have caught a rare and endangered fish, the coelacanth, off the coast of the Indian Ocean archipelago of Zanzibar, a researcher said on Monday. The find makes Zanzibar the third place in Tanzania where fishermen have caught the coelacanth, a heavy-bodied, many-finned fish with a three-lobed tail that was thought extinct until it was caught in 1938 off the coast of South Africa. Since then two types of coelacanth have been caught in five other countries: the Comoros, Indonesia, Kenya, Madagascar and Mozambique, according to the African Coelacanth Ecosystem Program. "Fishermen informed us that they caught a strange fish in their nets. We rushed to Nungwi (the northern reaches of Zanzibar) to find it's a coelacanth, a rare fish thought to have become extinct when it disappeared from fossil records 80 million years ago," said Nariman Jiddawi of the Institute of Marine Sciences, which is part of the University of Dar es Salaam in Tanzania's commercial capital. Trade in the coelacanth is banned under the Convention on International Trade in Endangered Species of Wild Fauna and Flora. "Zanzibar will join a list of sites of having the rare fish caught in its own waters," said Jiddawi, adding the catch weighed 59.5 pounds and measured 4.4 feet. Four fishermen caught the fish on Saturday, Jiddawi said. Mussa Aboud Jume, director of fisheries in Zanzibar, said that the coelacanth will be preserved and put on display at the Zanzibar Museum. A statement of the Institute of Marine Sciences said that 35 coelacanths have been caught since September 2003 in Mtwara, a southern region of Tanzania, and mostly along the coast of Tanga in Tanzania's north. Coelacanths are the only living animals to have a fully functional intercranial joint, a division separating the ear and brain from the nasal organs and eye, according to an Institute of Marine Sciences statement. When fish get emotional New Scientist July 9 Who ever heard of a fish being in two minds about something? Yet it seems that like humans, fish process information - and perhaps emotions - on different sides of the brain. Fish growing up in the wild among predators use their left eye to look at novel objects, while their offspring raised in captivity use the right eye. This suggests that life experiences can affect which side of the brain fish use, and even, says Victoria Braithwaite of the University of Edinburgh, UK, that they have emotional mindsets, since different sides of the brain may correspond to a curious or suspicious attitude. "The lab-reared fish could process information about novel objects in the left brain [which means they are looking at things with their right eye] because they feel more comfortable, whereas their parents are more cautious." Humans use their left and right brain lobes differently, the most well-known consequence being handedness. Brain lateralisation has been found in an increasing number of other species in recent years. "Especially for animals that have to cope with many predators, it is an advantage if they can use one hemisphere to keep an eye on predators while they use the other hemisphere to do other things," says Culum Brown, now at Macquarie University in Sydney, Australia. Brown and his team caught bishop fish (Brachyraphis episcopi), which are similar to guppies (see Photo), from areas with high and low predation rates in Panama. The team bred the fish in the lab and then tested the behaviour of both the wild parents and their offspring. Fish swam towards a slatted barrier through which they could see either a novel object (a yellow cross), nothing, or another bishop fish. They could then swim past the barrier either to the left or to the right. Exiting to the left meant the fish had kept its right eye on the barrier, and vice versa. Neither fish from areas of low predation nor their young showed much of a preference for a left or right exit, suggesting their brains were not very lateralised. However, fish that had to deal with a lot of predators in the wild favoured one eye, as did their lab-born offspring, especially when viewing the novel object (Animal Behaviour, DOI: 10.1016/j.anbehav.2006.08.014). "This shows that a tendency for brain splitting can be inherited," says Braithwaite. "But amazingly, the captive-born offspring preferred the right eye when their parents preferred the left. So the way the fish then use this brain division is a learned thing." Giorgio Vallortigara from the University of Trieste, Italy, who studies lateralisation in vertebrates, says that the left side of the brain directs approach behaviour and the right side withdrawal. Dogs wag their tail to the right when they see a friendly human but to the left when faced with a scary dominant dog, he found (Current Biology, vol 17, p R200). "The wild fish could similarly use their left eye here because they are frightened and more likely to withdraw," he says. But there is another explanation, says Brown. Left-eye preference for novel objects in wild fish could mean they have learned to take better advantage of their innate ability to lateralise: "Using the left lobe could simply be the default in this context," Brown says. Indeed, fish from low-predation areas showed a slight tendency to use the right eye in all tasks. Lab-born fish of parents from high-predation areas could be exaggerating this default right-eye bias because they have inherited strong lateralisation. However, since they've never met a predator, they haven't learned to pay special attention to novel objects using their right brain and left eye. Whether humans with differing life experience also vary in which brain side they use to deal with certain emotive stimuli is not yet known, but the researchers agree that such processing plasticity is likely in all lateralised species: "We know, for example, that stroke patients with damage to one hemisphere can learn to compensate with the other lobe," says Brown. And Vallortigara adds: "I would expect a dog who has never seen a human would feel more sceptical and wag its tail to the left." Study suggests sonar doesn't harm fish Science Daily July 9 A U.S. study suggests high powered sonar, such as used by Navy ships, does not harm fish. University of Maryland researchers studied rainbow trout housed in an experimental tank at the U.S. Navy Sonar Test Facility in Seneca Lake, N.Y. Led by biology Professor Arthur Popper and research associate Michele Halvorsen, the scientists found exposure to high intensity, low frequency, sonar did not kill the rainbow trout, nor did it damage their auditory systems, other than for a small and presumably temporary decline in hearing sensitivity. But Popper cautioned the finding should not be extrapolated to other fish species or the effects of other sound sources. He said there is considerable concern that human-produced (anthropogenic) sounds added to the environment could have damaging effects on marine life. While much of the interest has focused on marine mammals, such as dolphins and whales, there is growing interest in the effects of such sounds on fish. "The effects of sound on fish could potentially include increased stress, damage to organs, the circulatory and nervous systems," said Popper. The study is reported in the July issue of the Journal of the Acoustical Society of America. Rare fish mysteriously enter man-made pond It likely took a 1.5-mile joyride through piping but nobody knows for sure By Melinda Wenner MSNBC July 16 Scientists in Southern California have discovered a mysterious booming population of endangered desert pupfish in man-made research ponds designed for an entirely different purpose. Although no one knows exactly how they got there, the fish probably took a 1.5-mile joyride through the piping used to deliver water to the ponds. Last year, Douglas Barnum, a scientist with the U.S. Geological Survey’s Salton Sea Science Office, and his colleagues built four small ponds to study how ongoing changes in the Salton Sea — the largest lake in California, which is 25 percent saltier than the ocean — will affect nearby wildlife as part of the state’s ongoing Salton Sea Restoration Project. The Salton Sea, an important habitat for migratory birds, is slowly drying up and growing saltier. It is also becoming tainted with selenium as it is fed by a number of rivers, including the Alamo River, contaminated by selenium from the upper Colorado basin. The element, which may be leaching into the basin from agricultural sites, can be toxic to wildlife, especially as it accumulates through the food chain. “The birds are potentially eating a very toxic time bomb,” Barnum told LiveScience. To study how birds respond to the growing selenium levels as well as the changes in salinity, the scientists created man-made ponds, mixing the salty water from the Salton Sea with water from the nearby freshwater Alamo River to create a series of four ponds of varying salinity, all slightly contaminated by selenium. The plan was to study how bird populations respond to the different ponds, which are all carefully filled so as to prevent fish and other wildlife from being pumped in too. The water first travels through a trench with a rock barrier and then continues through one and a half miles of piping until reaching the ponds. It was therefore surprising when Barnum and his colleagues noticed a number of larger fish swimming around in the ponds this year. They assumed that all of the fish were a common species known as tilapia and that they had somehow survived the long trip from the lake or river to the ponds. But when they started doing some maintenance work a few weeks ago, they “noticed something that was a little bit odd,” Barnum said. They saw smaller fish in the ponds, too. “These were not Tilapia, and they didn’t look like anything else we had seen,” Barnum said. The tiny fish, they discovered, were actually endangered desert pupfish — populations of which have declined over the course of the past few decades thanks to a loss of habitat and changes in environmental conditions, such as dam-building, according to the U.S. Geological Survey. The scientists estimate that there are thousands of these endangered fish living in the research ponds, although most of them are young, and no one knows how many will survive into adulthood. They also aren’t sure whether the pupfish are coming from the Salton Sea or the Alamo River, but it’s likely that they somehow made it through the rock barriers and made the voyage through the piping. Young pupfish are smaller than a fingernail, so “they may be able to make it through the cracks in the rocks,” said Barnum. “It doesn’t sound possible, but who knows.” He added that it only takes two pupfish — a male and a female — to start a population. While it could be that pupfish are more prevalent in California’s rivers and lakes than anyone realized, it may also be that a few brave individuals just happened to make it to the ponds and, upon their arrival, mated like mad. This exciting windfall has prompted the scientists to try to broaden their research goals to include studies of the elusive pupfish as part of their project. “Let’s take advantage of this golden opportunity to learn something about this endangered species,” said Barnum. Flattieman.
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Good on ya, mate. That's a sea/bully mullet - they don't regularly feed on flesh baits etc. - your theories about it being hungry are probably very true! Looks like Sylvania Waters to me... Don't they fight! Flattieman.
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, reel invader! Do you have any pics of the jewie? Flattieman.
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Thanks, Donna. You're exactly right - ecoscience is looking fantastic - there's some awesome lecturers. One more sleep! I was just looking back through the Bar to catch up on the posts that I missed when I was incredibly busy - Happy Anniversary for the 21st (very belated, I know )!!! Thanks very much, Pete. What about Prof. Flattieman?! Flattieman.
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Guys. Hope you have a great day. Flattieman.