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Friday Fishy News - November 24


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Two fishermen rescued after nearly 30 hours floating in fish cooler

Tampa Bay 10


November 18

JACKSONVILLE, Fla. — Two fishermen who spent nearly 30 hours floating in a large fish cooler have been rescued.

Crewmen on a Navy aircraft spotted Duane Grove and Robert Christenson more than 70 miles off the coast of Jacksonville yesterday afternoon.

A Coast Guard helicopter later hoisted them to safety.

Both men were listed in good condition last night at St. Luke's Hospital in Jacksonville. They had mild hypothermia.

The Coast Guard says the pair's boat was hit by a large wave Thursday morning, listed and began to take on water. One man was knocked overboard; the other escaped through a window.

They had no life preservers and couldn't get to the life raft, so they climbed into the floating fishing box.

Scientists make, mate robot fish to prove theory

Xinhua News


November 21

A team of scientists thinks our ancient predecessors developed vertebrae and a backbone to stiffen their bodies so they could swim more powerfully and has developed robot tadpoles to help prove the theory.

The far-distant forebearers of humans and other vertebrates were much softer than their descendants. Instead of backbones they had flexible rods know as notochords. By evolving vertebrae the attached muscles could generate more force.

"The fossil record shows vertebrae evolved independently at least four separate times. That shows they must really be functionally important," said vertebrate physiologist John Long at Vassar College in Poughkeepsie, N.Y.

To test this idea, Long and his colleagues built robot fish with backbones of varying strength to simulate extinct animals. They then "mated" the best swimmers to see how generations of "offspring" evolved to swim better.

The robots -- "Tadros" -- were modeled after the larvae of marine animals known as sea squirts, swimming creatures that still have notochords.

Each Tadro had a single electronic eye, a motor, a computerized brain that controlled its motions, and tails made of gelatin of different lengths and stiffness. The robots had bodies between six and seven inches long, with tails two to four inches long, and swam along the surface.

The scientists raced three robots in eight-foot-diameter fish tanks, each swimming to and around a light hanging above the tank.

After seeing which fish swam best, the research team "mated" them using computer simulations that modeled the genetic mixing that occurs during sex to produce the next generation of Tadro tails. The best swimmer was given the greatest mating success and opportunity to pass along its traits, while poorer swimmers were less fortunate.

After 10 generations, Long and his colleagues found that as swimming performances improved, stiffer tails evolved.

"One thing vertebrates really brought to scene were large, fast, active animals, and this part of the anatomy has a direct connection with that," Long said.

But Long said that only 40 percent of the increased swimming efficiency could be related to stiffer tails, which meant other factors were involved, including how easily the tail turns.

"We plan to investigate what that next 60 percent is," Long said.

The research team intends to add a "predator" into the tank during the next swimming competition to see how Tadro tails evolve then. This hunter will try to collide with the robots, while the Tadros will try to avoid it.

This next generation of Tadros will detect the predator using infrared sensors that mimic the pressure-sensitive organs of fish, known as lateral lines.

"We also plan not just on making the backbone stiffer, but on putting in vertebrae, to make them bend, to have joints, and see how that changes things," Long said.

Long and his colleagues reported their findings online Nov. 17 in the Journal of Experimental Biology.

Palaeontologists uncover monster fish remains

Reporter: Iskhandar Razak

ABC News Online - The World Today


November 23

ELEANOR HALL: Two amateur palaeontologists have unearthed the remains of a prehistoric monster fish in the centre of Australia.

And the swordfish-like discovery has forced a complete re-examination of how marine life developed in the age of the dinosaurs, as Iskhandar Razak reports from Andamooka.

(sound of a person chipping away at rock)

ISKHANDAR RAZAK: For 15 years Tom and Sharon Hurley have been chipping away at surfaces across the continent.

SHARON HURLEY: He's dragged me into quartz quarries ...

TOM HURLEY: Up cliffs and sandy rivers.

SHARON HURLEY: Up cliffs, saying "Follow me along this cliff edge, we're going to find some fossil shells". I've said "Ok, well I'll go where you go".

We're just the keenest fossil collectors in the world.

ISKHANDAR RAZAK: You're amateurs, I guess, is that fair to say?


SHARON HURLEY: Yes, yes. Amateur.

ISKHANDAR RAZAK: How do you go about doing it?

TOM HURLEY: We ourselves spend a lot of time researching old literature.

SHARON HURLEY: Looking up the old, old literature is important.

TOM HURLEY: So, by going to museums and seeing where things are found, like what has been found and where, studying the geology maps, and then going there, spending your own time and money ...

ISKHANDAR RAZAK: And you pack up the four-wheel drive with all the gear that you need ...


SHARON HURLEY: Our GPS, and our ...

TOM HURLEY: And often right across Australia.

(sound of the iron door of the Hurley's ute squeaking shut)

ISKHANDAR RAZAK: The pair have found fossils displayed in museums across the nation. Recently near Boulia, about 250 kilometres north of Birdsville, they came across their greatest discovery yet.

TOM HURLEY: We've found two of three skulls of a very bizarre fish from Queensland. These fish are represented in America by six species from American inland seas 20 million years younger than the Australian inland seas, and we have found the oldest specimen ever found and the most complete specimen ever found.

SHARON HURLEY: This one is going to be named after us.

ISKHANDAR RAZAK: But before they get that honour, scientists have some work to do. Dr Ben Kear from the South Australian Museum is writing the paper on the animal for publication.

BEN KEAR: It appears to be a new genus and species of fossil fish, protosphyraena. Imagine it's like a giant swordfish barracuda. Two-metres long, highly predatory, two-centimetre long teeth, it eats whatever it wants to.

And the interesting thing about the Australian one is that they're ancestors of the more well known forms from the Northern Hemisphere. So, what this is telling us is that perhaps these polar faunas down in Australia might have been some sort of factory for species.

ISKHANDAR RAZAK: Australia being the melting pot, the spawning pond?

BEN KEAR: The origin, the origin for a lot of these groups. An interesting thing about this protosphyraena, however, and this new animal that we're finding in Australia, is that they've got very long front fins.

In fact the fins are nearly the length of the body, with these huge sort of trailing things with serrated saw-like edges. It might have used these things to stun prey and then picked them off.

ISKHANDAR RAZAK: Would it use its head as well?

BEN KEAR: Absolutely. The snout of this thing is nearly 40 centimetres long and tapers to nice, sharp point. It's not (laughs) ... you can imagine it doing some damage. So, yes.

ISKHANDAR RAZAK: Dr Kear says the fish will carry the name Hurley, but he can't reveal exactly what the Australian protosphyraena will be called yet.

BEN KEAR: There's actually rules. There's very, very strict rules that go to naming fossils. You have to basically restrict the name until it's finally published. But before then if the name is used, unfortunately it becomes invalid.

ISKHANDAR RAZAK: But for the fiercely patriotic Tom, it's just good to put points on the board for Australia's prehistoric life.

ISKHANDAR RAZAK: The Americans really love this fish?


ISKHANDAR RAZAK: They claim it as their own?


ISKHANDAR RAZAK: This is going to change all that isn't it?

TOM HURLEY: Yes, it's just given the American, great iconic swordfish fossils an Australian lineage.

ISKHANDAR RAZAK: And the fish isn't the only discovery that may soon to carry the name Hurley.

TOM HURLEY: We've also found fossil sea lice on a fossil fish head last year. They are also going to be named. Sharon didn't want them named after herself. She said ...


TOM HURLEY: I can get them named Tom Hurley-i.

ISKHANDAR RAZAK: So they're going to be your own special sea lice?

TOM HURLEY: Yep I'll get ...

SHARON HURLEY: No, no ....

TOM HURLEY: ... I'll get known as the sea louse.

ELEANOR HALL: Palaeontologists Tom and Sharon Hurley speaking to Iskhandar Razak in Andamooka.

Fish will change attitude to fit in in school

Tenille Bonoguore


November 22

Fish have personalities and will change their behaviour to fit in with other fishes, researchers from the University of Liverpool have found.

Rainbow trout were deemed ‘bold' or ‘shy' depending on how they reacted to Lego blocks being dropped into their fish tank: If they went to investigate the new blocks quickly, they were bold. Fish that shied away from the new stimulus were shy.

The researchers then compared how these fish reacted when given a chance to mingle with other fish, and when put in view of another fish in a different tank.

It turns out, shy fish tend not to take on bolder fish when competing for territory, but if they come up against other shy fish they can start to adopt the outgoing traits of the bold fish. The researchers surmised this could be because the shy fish recognize the shyness, and are willing to take on a competitor they think they can beat.

Bold fish, on the other hand, will tone down their behaviour to fit in with more shy counterparts.

Dr. Lynne Sneddon and Ashley Frost, from the University's School of Biological Sciences, let the fish interact for 15 minutes a day for one week.

“Rainbow trout are a highly aggressive species and naturally form relationships of dominance in a very short time period. They chase after each other to try and exert their dominance,” Dr. Sneddon said.

“We found that bold fish that lost their ‘battle' became shyer than usual and shy fish who won their ‘battle' became bolder.”

The more time the fish spent together, the more their behaviour changed, she said.

Dr. Sneddon told the London Times that the idea that fish have poor memories that only retain information for a matter of seconds was a myth.

“Studies have shown that fish can remember for anything up to three years, and current thinking in fish biology is that fish are very diverse in behaviour within any population,” she told the Times.

“They also learn from their experiences: They adjust their behaviour according to what they pick up from others.”

The research was published on Wednesday by Proceedings of the Royal Society of London B.

Cousteau urges action on declining fish stocks

Reporter: Brendan Trembath

ABC Online - The World Today


November 17

PETER CAVE: An acclaimed diver and documentary maker is disturbed by declining fish stocks in the world's ocean and he wants the Australian Government to do more about it.

Jean-Michel Cousteau is calling for more marine sanctuaries like Australia's Great Barrier Reef.

The New South Wales Government is close to announcing the boundaries for two new marine sanctuaries.

But Jean-Michel Cousteau who's visiting Australia says it's still not enough.

This report from Brendan Trembath.

BRENDAN TREMBATH: Jean-Michel Cousteau has been diving since he was a little boy.

JEAN-MICHEL COUSTEAU: My father pushed me overboard. I was seven years of age. I had a tank on my back and this was exactly 61 years ago.

BRENDAN TREMBATH: His father was the famous ocean explorer Jacques Cousteau who co-invented the breathing apparatus used by most divers.

He also made many documentaries which introduced many people to the wonder of the undersea world.

(sound of documentary music)

NARRATOR: Calypso floats off a coral continent.

As the rediscovery of the world brings the Cousteau team to Australia, an adventurer's land of turbulent history, (inaudible) shores, remote exploration and a marine monument so vast, so irreplaceable the United Nations declared it the heritage of the world – the Great Barrier Reef.

BRENDAN TREMBATH: Jean-Michel Cousteau is concerned about how few fish are in the sea these days because of over-fishing.

He says Australia and other nations have to declare more marine sanctuaries.

JEAN-MICHEL COUSTEAU: I eat fish. I'm not a hypocrite and I want to be able to continue to do so.

But, the way the world is behaving today with a growing demand on finite resources, we are now in a position where we can say – and it's scientifically established – that we are emptying the ocean.

Those resources are disappearing at a very, very fast pace. Today we can say that 90 per cent of all the pelagic fish, or the large fish of the oceans of the world are gone, that's the bad news. The good news is that there are 10 per cent left. And if we do the right thing, which is a management issue, we can restore some of those resources.

BRENDAN TREMBATH: Jean-Michel Cousteau has expressed his concern about declining fish stocks during a visit to Sydney Aquarium.

It helped him make his point about why the oceans are worth saving.

Schools of fish moved in, as aquarium staff doled out an early lunch.

(sound of feeding fish)

Can you just give me an idea of what sort of varieties of fish you're feeding here?

AQUARIUM ATTENDENT: Yeah, sure we're feeding out some large squid, some small squid, pilchards, mussels, prawns, and also some bigger fish for some of the sharks, like some large trevally, salmon and mullet.

BRENDAN TREMBATH: One of Australia's best-known divers shares Jean Michel Cousteau's view that more sanctuaries are needed.

Valerie Taylor regrets she used to take many fish from the sea when she used to be an award winning spear fisher.

VALERIE TAYLOR: I have been a diver for over 50 years. I'm still diving although I'm in my 70s.

I have seen the ocean life off the coast of New South Wales, actually off the coast, all of the east coast disappear before my eyes.

I started off as a spearo. I thought there were so many fish in the ocean that you could never, ever fish them out, and I saw it happen in a few years. Particularly around the reefs where the spear fishermen used to work.

PETER CAVE: Australian diver, Valerie Taylor ending that report from Brendan Trembath.


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