Great White sharks looking for Love

An area of concentrated activity between Hawaii and the Baja Peninsula, known as the “White Shark Cafe” is revealed in this map by 47 great whites equipped with satellite tags.

Satellite tagging by TOPP (Tagging of Pacific Predators - www.topp.org) reveals a previously unknown behavior of white sharks travelling long distances each winter to concentrate in the Pacific for up to six months. During these months, both males and females make frequent, repetitive dives to depths of 300 meters, which researchers theorize may be significant in either feeding or mating habits and reproduction.

“There is something going on there but as yet we don’t know,” said marine biologist Professor Ron O’Dor. “Maybe it’s just a good place to pick up girl sharks.”

The Census of Marine Life is a global network of researchers in more than 80 nations engaged in a 10-year scientific initiative to assess and explain the diversity, distribution, and abundance of life in the oceans. The world’s first comprehensive Census of Marine Life - past, present, and future - will be released in 2010.

Census of Marine Life Project Map

shark immune system secretion inhibits growth of human cancer tumours…

Studies into the low rate of disease amongst sharks leads to exciting implications for human cancer treatment.

Scientists have spent 10 years using carcinogens to try to induce cancer in sharks and skates, to no avail. After turning their attention to trying to understand shark immunology, they were able to confirm that sharks have a unique lymphoid tissue, not present in any other animals, that does nothing but make immune cells.

These unusual immune cells were found, in the lab, to secrete a substance that inhibits human tumor cells. So far they’ve tested the substance–they’re still not exactly sure what it is–on 18 different human tumor cell lines, including breast and pancreatic cancer. It’s inhibited all of them.

Funding is now being sought for further testing, efforts to further understand and identify sharks’ tumor-inhibiting secretion, making it possible one day for scientists to synthesize it.

From Forbes.com: Read more

Mediterranean Hammerhead shark population fallen by 99.99%

Conservationists have examined historical fishing records which show that sharks in the Mediterranean Sea have suffered dramatic declines in the past few decades due to overfishing.

The scalloped hammerhead shark. A team of scientists at Dalhousie University in Nova Scotia, Canada, examined fishery logbooks that chart the demise of several shark species. The records show hammerheads all but vanished from coastal waters in 1900, and have barely been spotted in the open sea for 20 years. They say the hammerhead population has fallen 99.99% in 200 years.

Some thresher shark species have dwindled by more than 99%, according to the fishing records examined by conservationists.

Records from long-line fisheries suggest a 99.99% fall in mackerel sharks. The typical size of sharks caught in the Mediterranean is among the lowest in the world, indicating that more young sharks are being caught.

Since the mid-1950s blue sharks have declined by 96.5%.

Conservation groups fear that without strict catch limits on sharks, many of the 47 species in the Mediterranean will soon become locally extinct.

From the Guardian.co.uk: See slideshow story

Olympic swimmers learn from Sharks

When winning an Olympic gold medal in swimming is the goal, it helps to take inspiration from some of the best swimmers in the world — sharks and dolphins — and that is exactly what U.S. Olympic team swimmers have been doing as they train.

From suits to strokes, coaches, researchers and other advisers are making sure that their athletes benefit from fish and marine mammals’ natural swimming abilities.

“Some of our athletes are now wearing what are called ’shark skin suits,’” Russell Mark, biomechanics coordinator for U.S.A. Swimming, told Discovery News.

“These aren’t made of actual shark skin, of course, but they are slippery in feel, like sharks, and they make the wearer move faster than normal in the water by reducing friction and drag,” he explained.

Mark also indicated that excelling at the dolphin kick can make or break a swimmer’s race.

From Discovery News: Read more