Surgeons are crediting the quick response of bystanders with saving the life of British shark attack victim Michael Cohen. Cohen’s right leg was severed by a bite from a white shark (Carcharodon carcharias) while swimming of Fish Hoek beach in Capetown, South Africa.

The Daily Mail reports that Hugh Till and Douglas Drysdale, who were in the area trying to spot whales, witnessed the attack and entered the water to assist Cohen back to shore. Bystanders applied a tourniquet to Cohen’s leg using a wetsuit and belt quickly after he was brought to beach following the attack. Surgeon Andrew Nicol told reporters that the quick action and proper first aid applied by those on the scene helped saved Cohen’s life.

The UK’s Channel 4 News reports that lifeguards told Cohen not to enter the water, due to three white sharks being spotted over a 90 minute period. According to the report, Cohen told the lifeguards that he was going in and that they should blame him and not the sharks, in the event of an attack. As of yesterday, Cohen remains hospitalized, recovering from his injuries, according to The Daily Mail.

If you’re a shark fan or nature enthusiast, you’re probably no stranger to BBC’s Planet Earth series. The high-speed camera footage of a white shark seen in the clip above has become one of the hallmark scenes from the series. Starting today (October 4, 2011) two new editions of the series are available on Blu-ray and DVD.

From BBC:

This fall, experience the ultimate portrait of our world like never before as BBC Earth releases Planet Earth Special Edition and Planet Earth Limited Collector’s Edition to Blu-ray and DVD October 4.

Planet Earth Limited Collector's Edition (TM & © BBC)

Planet Earth: Special Edition will feature improved picture quality which takes advantage of advances in high-definition technology since the original release. Additionally, over 3 hours of new bonus materials including video diaries, a new Greatest Planet Earth Moments feature, and the bonus series Planet Earth: The Future. The Limited Collector’s Edition features a numbered collectible globe case and an exclusive set of 4 art cards in addition to the 6-disc Special Edition items.

In a video from C&EN, Georgetown University’s Dr. Michael Zasloff talks about how squalamine, a steroid found in sharks in the dogfish family (Squalidae), could help to fight viruses in humans. While searching for animals with exceptional immune systems, Dr. Zasloff happened upone dogfish sharks due to their ability to fight off infection.

Dr. Zasloff points early on that they “do not kill sharks” to get the squalamine used in human studies, because the squalamine molecule can be synthesized from a soybean steroid. While clinical trials are still in the early stages, Dr. Zasloff says that he is “quite optimistic” about squalamine’s potential to treat certain diseases in humans.

YouTube user ELVIAVANES uploaded the video above today, which is described as a great white shark being rescued at California’s Venice Beach. The video description says that the juvenile shark was hooked on a rod and reel by locals. The description goes on to say that the hook was removed. Four men, including two surfers, can be seen assisting the shark back into the water at the video’s end.

The great white shark (Carcharodon carcharias) is a protected species in California waters.

KHON2 reports that a veteran canoe paddler had a encounter with a shark that bit his canoe twice. Tom Bartlett was paddling about a half-mile from shore off of Kauai, Hawaii when the shark bit the front of his boat, released it and then came back and bit the canoe again. While Bartlett tells KHON2 that the shark wasn’t “ripping or tearing” at his canoe, the damage was enough to cause the vessel to take on water and begin sinking. Bartlett was able to paddle to shore despite the compromise to his canoe’s hull.

Bartlett did not know what kind of shark bit his canoe, but he says the bite marks indicate that its jaw was about 13-inches wide. While his canoe sustained some damage, Bartlett walked away from the encounter unscathed and was thankful that he himself was not bitten.

The Virgin Group’s Richard Branson and former NBA star Yao Ming have recently been featured in the media speaking out against the consumption of shark fin soup. The UK’s Telegraph shared the video above on their YouTube channel which features previously seen footage of Branson swimming with whale sharks and speaking out about threatened species. The end of the video features Ming’s latest WildAid PSA targeting shark fin soup consumption.

UPDATE: A reader has pointed out that the distance from the nearest point on Catalina Island to San Pedro’s Cabrillo Beach is approximately 18 miles, as the crow flies. Another reader has explained how the 30 mile distance was approximated in the comments.

30miledive.com is reporting that undersea explorer Scott Cassell completed his dive from Catalina island to San Pedro, California this past Saturday (September 17). Cassell was attempting to break a world record for a continuous dive, but equipment issues required Cassell to surface mid-way through the journey.

According to 30miledive.com, Cassell continued on with the dive after a brief surface interval on a support boat and completed the underwater trek in approximately 12 hours.

According to Cassell, his motivation for the dive was to “raise awareness about our shark populations.” He goes on to say that he remembers seeing many blue sharks (Prionace glauca) 20 years ago in the same waters he recently completed the distance dive. However, during his dive on Saturday, Cassell states that he did not see a single shark.

Photo courtesy of National Geographic. ©Michael Aw / National Geographic

The upcoming October 2011 issue of National Geographic magazine will feature the story “Sharing With Sharks,” which documents interactions between whale sharks (Rhincodon typus) and local fishermen off the island of New Guinea. The world’s largest species of shark is known to congregate in the area, where they have been observed searching for “free meals” either by pilfering a fisherman’s net or through voluntary hand-outs from the fishermen.

From National Geographic…

The giant fish is hard to study in part because it is hard to find and track. By tagging individual specimens, scientists have learned that whale sharks can log thousands of miles in years-long trips. But they sometimes disappear for weeks, diving more than a mile down and resting in the chilly deep for a spell. No one has ever found mating or birthing grounds.

Whale sharks are ordinarily loners. But not in one corner of Indonesia. The photographs on these pages, shot some eight miles off the province of Papua, reveal a group of sharks that call on fishermen each day, zipping by one another, looking for handouts near the surface, and nosing the nets—a rare instance when the generally docile fish act, well, like the rest of the sharks.

You can check out the entire online story at National Geographic’s "Sharing With Sharks". For more of Michael Aw’s photos taken on-location while working on this story, visit National Geographic’s accompanying "Sharing With Sharks" photo gallery.

"Sharing With Sharks" is featured in the October 2011 issue of National Geographic magazines, on newsstands September 27.

BBC News reports that squalamine, a chemical found in the Squalidae family (dogfish) of sharks, has been found to be a “good antiviral candidate” due to its documented ability to kill a wide range of human and animal viruses. While more research needs to be done to investigate the potential use of the chemical as a means of treatment for human diseases, squalamine can be easily reproduced synthetically and has shown no signs of major adverse side effects when given to patients in clinical trials to stop the growth of cancer cells, according to the BBC report.

You can check out the entire story over at the BBC News site.

Jonathan Green recently posted a promotional video video for the Galapagos Whale Shark Project. The project is a collaborative effort of several organizations and involves tagging whale sharks (Rhincodon typus) with satellite tags with the goal of learning more about the species and increasing public knowledge about whale sharks.

For more information about the project, visit the Galapagos Whale Shark Project website.