Friday Fishy News - 22 September

[Flattieman]

Robot allows fish to roam land

Updated Thu. Sep. 21 2006 3:50 PM ET

Brian Jackson , DiscoveryChannel.ca

A fishbowl hooked up to a pair of wheels and a computer allows a goldfish access to land.

Artist Seth Weiner is calling the invention contemporary art. "The Terranaut Project" is on display at the Exit Art gallery in New York until Dec. 23.

A camera mounted above the fishbowl is pointed down and tracks the fish movements. The information is then wirelessly transmitted to an onboard computer. There, the fish movements are converted into wheel movements.

It won't be seen racing down the street any time soon. The vehicle moves much slower than walking-speed.

It's also unlikely the fish can appreciate the experience - the bending of light caused by the concave fishbowl ruins visibility to the outside world. But that hasn't stopped the fish from 'growing new legs' in the world of web-fame.

From a YouTube video to being featured on tech-nerd web pages and blogs, to winning a contemporary art award voted on by readers of an online newspaper, Terranaut is literally everywhere.

Some Fish Sniff Out Their Siblings

By Jeanna Bryner

LiveScience Staff Writer

18 September 2006

LiveScience.com

In the fish world, traditional roles are typically reversed with the male building the nest, completing nest-keeping tasks, and protecting and caring for the young. Since female fish lay their eggs in an already-built nest before swimming away, the hard work ensures a male fish will pass along his genes.

But not all fish obey this rule.

Some male bluegill sunfish, a freshwater fish living in North American lakes and streams, balk at the fatherly responsibilities of nest-building and parental care. At or before a male reaches two years old, he chooses to become either a father figure staying close to his nest or a promiscuous mate labeled a cuckolder.

Sneaky sex

A cuckolder can still reap the benefits of passing along his genes without having to take care of fatherly tasks, however. Once a female sunfish releases her 50 or so eggs into a nest, often a sneaky male will swoop by and swiftly fertilize the eggs.

"If they decide to go down the cuckolder life history, that is the parasitic one that doesn't provide parental care, they become fixed in that for life, they'll spend life being be a cuckolder," co-researcher Bryan Neff of the University of Western Ontario told LiveScience.

In nests swindled by several cuckolders and often containing eggs from several females, many of the resulting offspring are not related. This fishy lifestyle makes it difficult for nest-mates to identify their real siblings. Now researchers have discovered how the baby bluegill recognizes genuine siblings.

Smell this

Neff and colleague Tim Hain first had a fish of known origin swim around in a tank of water for a couple of days, "urinating and excreting various molecules from their body that provide an odor," Neff explained. The team repeated this with unrelated bluegill, gathering the scented water separately. Then they poured a kin-scent into one side of a fresh tank and another scent into the other side.

Bluegill born from cuckolder nests swam over to the tank section holding kin-scent, spending most of their time in that area.

"They're essentially saying, ‘does this individual smell a lot like me?' And if they do, they can be pretty sure that the individual is their brother or sister," Neff said.

The reasons for such active recognition are not clear yet to the researchers. Neff said the true siblings may help one another by not fighting in the nest, and once they leave the nest they might cooperate in foraging and defending against predators.

The study is detailed in the current issue of the journal Current Biology.

Unloved fish feeds zoo seals

MU program develops market for flying carp.

By TERRY GANEY - Columbia Daily Tribune

Published Monday, September 18, 2006

A fish that’s becoming a growing problem in Midwest rivers might end up being fed to sea lions and penguins in zoos if a pilot project successfully develops.

Both species seem to be taking over the Mississippi, Missouri and Illinois rivers. Silver carp are particularly hazardous because they’ve been known to leap out of the water and land in boats.

"These are powerful, powerful fish," said Rob Hayward, an MU fish researcher. "A 25-pound fish jumping 8 feet out of the water and landing in a boat creates quite a hazard."

Work is under way to develop fish patties made of ground up Asian carp that can be served as food to captive zoo animals. If the commercial market develops, it could provide multiple conservation benefits.

One dividend would be a reduction in the number of the troublesome fish in the rivers. The other benefit is the reduction in fishing pressure on species such as herring and mackerel, which are now fed at zoos at a cost of 30 to 70 cents per pound.

Ellen Dierenfeld, a fish nutritionist at the Saint Louis Zoo, said the carp food source could be modified to provide for additional fat content and nutrient quantity. Questions still abound about texture and whether the fish food will stick together when the trainer tosses a morsel to a sea lion for positive reinforcement. "We’ve done the toss test of a cake," Dierenfeld said today. "A couple of interns have thrown them back and forth to make sure they hold together and to make sure the texture is right.

"The animal palate will be the trickiest," Dierenfeld added. "We can make the most nutritious diet, but the animal may not like it."

With humans in the United States, that’s certainly a problem. Hayward said the Asian carp is in high demand on dinner tables in Asia and Europe. If Americans craved the fish the way others around the world do, there wouldn’t be a population problem in U.S. rivers. "This is the most commonly consumed fish worldwide," Hayward said. "We are the oddballs."

The Asia carp species were first noticed in 1993. No one knows how they got into the rivers, but some suspect that they might have escaped an impoundment in the south during the great floods that year.

Duane Chapman, a research fish biologist with the U.S. Geological Survey, said the Asian carp feed on tiny fish and plant organisms that are food sources for small fry of native species. Chapman said while it’s difficult to measure the carps’ impact, a recent natural survey in Illinois found that samples of bigmouth buffalo and gizzard shad were smaller than in the past - an indication that they are growing more slowly than before.

At the same time, Chapman said Asian carp grow quickly, making it difficult for them to be prey for predators such as walleye and flathead catfish.

Hazard, Chapman and Dierenfeld hope the project will create a market that will make it worthwhile for commercial fishers to collect the Asian species with nets.

"We hope to have a product ready to test with animals that’s nutritionally complete in the spring," Dierenfeld said. "Now, if the fish eaters will just bite into it."

Climate change makes fish migrate - experts

iol.co.za

September 20 2006 at 01:36AM

London - A warm-water Atlantic triple fin fish has, for the first time, been caught off the coast of Britain, in another sign of species migrating north as global temperatures rise, experts said on Tuesday.

The triple fin fish is usually found off the coasts of Africa, South America and the Mediterranean, but was caught by fisherman Michael Roberts in the Bristol Channel, where he was hoping to catch salmon and sea trout, they said.

The 60cm mature adult was handed in to the National Museum of Wales in Cardiff, where expert Julian Carter said that its discovery was another indication of the warming of British waters.

He was using a stake net off the shore at Peterstone, between Cardiff and Newport on the south Wales coast.

"It is the first record of such a fish in UK (United Kingdom) waters," Carter said. "It is a very warm water fish."

In August, a fisherman looking for salmon off the north-east coast of England caught a large swordfish far away from its natural habitat in the Mediterranean, experts said.

In July, scientists reported that a shoal of sunfish - the world's largest bony fish - had been spotted in the waters off Cornwall, south-west Britain, despite normally being found thousands of kilometres away.

The sunfish, which is usually considered a warm water species, is a flat oval beast weighing up to a ton and growing up to three metres long.

Described by biologists as a "swimming head" or a "giant pancake of a fish", they have migrated from the warmer waters of the equatorial Atlantic Ocean to feed on the mass of jellyfish attracted to British waters by high temperatures.

Fatty Fish May Protect Against Kidney Cancer

09.19.06, 12:00 AM ET

Forbes.com

TUESDAY, Sept. 19 (HealthDay News) -- The heart-healthy omega-3 fatty acids abundant in fatty fish like salmon and sardines may help protect your kidneys against cancer, new research suggests.

A large, 15-year Swedish study of women looked at fatty and lean fish consumption and the risk of kidney cancer. The finding: Those who ate high amounts of fatty fish -- more than one serving a week -- had 44 percent less risk for developing renal cell carcinoma (the most common form of kidney cancer) than those who did not consume any fish.

"That's substantial," said Eugenia Calle, director of analytic epidemiology for the American Cancer Society. "There is very little published on this topic -- it may be the only study to look at fatty fish and kidney cancer."

The findings were published in the Sept. 20 issue of the Journal of the American Medical Association.

Previous studies on fish consumption and cancer risk produced inconsistent results, Calle said, and they were limited in that they looked at all types of fish consumption. There has been some experimental data with animals and cells that suggest fatty fish, with their abundance of omega-3 fatty acids and Vitamin D, may protect against cancer, she added.

The Swedish study, led by Alicja Wolk of the Karolinska Institutet in Stockholm, "is probably the first study to look at fatty fish consumption. There's a lot of hypotheses but not a lot of studies yet," Calle said.

The study investigated the association between fatty-fish and lean-fish consumption and the incidence of kidney cancer in 61,433 women. Fatty fish included salmon, herring, sardines, and mackerel; lean fish included cod, tuna and fresh water fish; and seafood included shrimp, lobster and crayfish. The participants answered a food frequency questionnaire when they entered the study in 1987 and in September 1997.

During an average 15-year follow-up from 1987 to 2004, 150 kidney-cancer cases were diagnosed. The researchers found a lower incidence of kidney cancer in women who ate fatty fish once a week or more, but found no association with lean fish or other seafood consumption.

"In this large population-based cohort with data on long-term diet, we found that women who consumed one or more servings of fatty fish per week had a statistically significant 44 percent decreased risk of RCC (renal cell carcinoma) compared with women who did not consume any fish. Women who reported consistent long-term consumption of fatty fish at baseline and 10 years later had a statistically significant 74 percent lower risk," the authors wrote in a prepared statement.

"Our results support the hypothesis that frequent consumption of fatty fish may lower the risk of renal cell cancer possibly due to increased intake of fish oil rich in eicosapentaenoic acid and docosahexaeneoic acid as well as vitamin D. Our results, however, require confirmation because this is the first epidemiological study addressing this issue."

The Swedish researchers noted there are "large differences between fatty fish and lean fish in the content of omega-3 fatty acids and vitamin D. Marine omega-3 polyunsaturated fatty acids are 20 to 30 times higher in fatty cold-water fish than in lean fish. Fatty fish has three to five times higher content of vitamin D than lean fish, and lower serum vitamin D levels have been associated with development and progression of renal cell carcinoma."

The Swedish findings conflict with a major review published earlier this year that found omega-3 fatty acids derived from fish or fish-oil supplements did not prevent cancer.

A review of more than 38 studies found no evidence that diets rich in fish fight any kind of malignancy. These conflicting data showed omega-3 fatty acids "definitely have health benefits, but they are not a panacea. Preventing cancer is not one of the things omega-3 fatty acids do," said lead researcher Dr. Catherine MacLean, a natural scientist at Rand Health and a rheumatologist at the Greater Los Angeles VA Healthcare System. The study was published Jan. 25 in the Journal of the American Medical Association.

Kidney cancer isn't that common in the United States, Calle said, ranking No. 7 for men and not making the top 10 cancers for women. "This is not a common cancer, so the public health impact is not as great as it would be, say, for breast, lung, prostate," she said. But, in terms of general interest, "if [fatty fish] were associated with a decreased risk of additional cancers, that would be a very important message."

"You can't go wrong eating fish," Calle said, adding that the American Cancer Society does not have specific recommendations on the type of fish to eat. "As more data become available, our dietary recommendations are reviewed and updated.

Plight of bluefin tuna highlights EU's fish crisis

By Ahmed ElAmin

nutraingredients.com

18/09/2006

Bluefin tuna has almost been fished out of some of the Mediterranean’s oldest fishing grounds, according to new data released by the World Wildlife Fund (WWW), a global conservation organization.

The organisation, along with industry representatives, will present the findings today before a meeting of EU fisheries and agriculture ministers. The WWW is calling on the European Commission to take drastic action in stopping overfishing of the species.

The Commission on Friday also set out its guiding principles for cutting fishing quotas in 2007, playing the middle ground between politics and scientific warnings that stocks of certain species such as cod are close to collapse.

Scientists, organisations like the WWW, and the European Commission have been calling on EU member countries to make drastic cuts in fishing quotas for many species, especially cod and tuna. The cuts, if approved by the bloc's legislators, with further increase the dependence of EU food processors on foreign supplies.

It could also result in more production coming from aquaculture rather than wild fish stocks as governments face up to the fact that the world's oceans are being depleted at unsubstainable rates.

The WWW report further serves to emphasize the crisis by highlighting the state of Mediterranean tuna. Catches around Spain's Balearic Islands in the western Mediterranean, for example, are down to just 15 per cent of what they were just a decade ago, the WWW report stated. Only 2,270 tonnes have been caught there this year — mainly by French and Spanish fleets — compared with 14,699 tonnes in 1995.

The data also reveal that Mediterranean bluefin tuna farms — which would usually be filling up by this time of year — have experienced substantial decline.

From 2006's catches of wild Mediterranean tuna, some 22,520 tonnes have been put in captivity and farmed — a 25 per cent reduction compared to 30,000 tonnes farmed last year. Six Spanish tuna ranches have already ceased operating altogether because there were simply no more tuna, the WWW stated.

“The new data point to the risk of economic collapse in the Mediterranean bluefin tuna fishing and ranching sector,” stated Roberto Mielgo Bregazzi of Advanced Tuna Ranching Technologies and author of the WWF bluefin tuna report. “The Mediterranean bluefin tuna species is under threat and many jobs in the tuna fishery are being jeopardized. The situation is alarming.”

The WWF is urging the Commission to support a strict recovery plan for the fishery, including the closure of industrial fishing during the spawning season, real-time monitoring of fishing and farming activities, the compulsory placing of observers on board all tuna vessels and in tuna farms, and the setting of a scientifically based minimum catch size.

As if in answer the Commission on Friday set out its guiding principles for cutting fishing quotas in 2007. The Commission's limits attempts to heed the scientific warnings but also cater to the politics in the industry, which is resisting the inevitable job losses.

If adopted the policy could reduce the domestic supply and result in processors having to look more and more for imports from non-EU countries.

The Commission is suggesting that the bloc adopt a maximum sustainable yield policy (MSY) to control overfishing and reduce production.

Maximum sustainable yield is the highest yield that may be taken from a fish stock without lowering its productive potential for future years.

The Commission will propose to fisheries ministers that member countries cut their quotas on overfished species by up to 15 per cent a year, a graduated reduction aimed at helping the fishing sector adjust to lower catches. In the case of those cod stocks falling under the recovery plan, there had been no detectable recovery as of December 2005.

For 2007, the Commission will propose limits if scientific bodies are able to provide quantitative estimates of stock size and fishing mortality. If no such estimates can be supplied, the Commission will propose a reduction of 25 per cent in catch levels for cod, and a reduction of 25 per cent in fishing days for mixed fisheries that catch cod.

Most European fish stocks are now overfished, according to the influential International Council for the Exploration of the Sea (ICES). In its annual report to the Commission last October, the scientific body called for a complete overhaul of deep-sea fisheries in the north east Atlantic, which accounts for 60 per cent of the EU's production.

The scientists called for drastic measures to be taken until a full assessment on the situation is completed. The ICES annual assessment is used by the European Commission in recommending levels in the annual quota negotiations.

Scientists have submitted reports stating that the current rates of overfishing on EU stocks vary on average from two to five times the level that would provide the highest catch. The overfishing has led to lower catches, lower incomes for fishermen, low profitability in many fisheries, and high catches of young fish - many of which are discarded, the Commission stated.

In a communication published on Friday, the Commission proposes to set management measures based on the level of biological risk each species faces.

The six categories of fish stocks identified are stocks which are currently fished according to the principles of maximum sustainable yield (MSY), stocks that are overfished but inside safe biological limits, stocks outside the safe biological limits, stocks subject to long-term plans, short-lived species and stocks for which the precise state is unknown but which are not at high biological risk.

Maximum yields for species classed as being fished outside the safe biological limits will face the 15 per cent cut in quota, or more if the situation is urgent.

Last month the European Commission proposed cutting quotas on cod, salmon and other Baltic Sea species, in some cases by up to 20 per cent.

Annual fishing quotas are ordinarily set out in a regulation proposed by the Commission in late November – after receiving scientific advice in mid-October - and voted on in the December Council of Fisheries Ministers.

Last October scientists from the influential International Council for the Exploration of the Sea (ICES) called for a complete overhaul of deep-sea fisheries in the north east Atlantic, which accounts for 60 per cent of the EU's production.

The ICES annual assessment is used by the European Commission in recommending levels in the annual quota negotiations.

The ICES recommended that all existing deep-sea fisheries should be cutback to low levels until they can demonstrate that they are sustainable, the organisation said in a press statement.

They advised a complete halt to depleted deep-sea sharks, and they will recommend that no new fisheries for deep-sea fish should be allowed until it can be demonstrated that they are capable of being sustainable.

The report also called for a halt to catches of spurdog, basking shark, porbeagle, common skate and thornback ray. They want a halt to cod fishing in the North Sea, the Irish Sea and west of Scotland.

They want the fishing of hake to be stopped in the Iberian peninsula. A complete halt to fishing for sandeel in the North Sea and pout in Norway.

Cod stocks in the North Sea, Irish Sea and west of Scotland remain well below minimum recommended levels and the advice for these stocks, and Iberian Peninsula hake, which is also still in poor condition, is zero catch.

Whiting in the Irish Sea are also thought to be in poor condition so the advice is for the lowest possible catch until the stock has had a chance to recover. ICES also advised that North Sea plaice and sole need further reductions in catch, or effort, to let the plaice spawning stock increase and to prevent the sole spawning stock from declining in the near future.

According to Eurostat, the EU's 25 members produced about 7.6 million tonnes of fishery products in 2002. Denmark (1.47 million tonnes) was the largest producer in 2002, followed by Spain (1.15m tonnes ), France (0.95m tonnes) and the United Kingdom (0.87m tonnes). The four members accounted for 60 per cent of the total EU production.

Production in all states fell by 17 per cent from 1995 to 2002. Aquaculture represents 17 per cent of total production.

Earlier this year Greenpeace launched an attack on retailers who it claims “do next to nothing to ensure that their fish is sourced from sustainable sources”. The group has called on supermarkets to face up to their responsibilities and ensure their seafood products are sourced from environmentally friendly sources.

"Globally, three quarters of commercial fish stocks have been fully exploited and nearly 90 per cent of stocks of large predatory fish are already gone," the group claims.

Flattieman.

Edited September 22, 2006 by Flattieman

[Guest BBM Rick]

Jeez, what a read!!!

Love your work mate, thanks for that.

Rick.