The Dorsal Fin

A video report from Australia’s 7News features some amazing footage caught by the crew of a sea rescue helicopter depicting a massive feeding event involving bait fish, tuna, sea birds, and multiple species of sharks. The footage was shot off the coast of Perth, Australia. According to the report, most of the sharks seen in the footage are spinner sharks (Carcharhinus brevipinna) and blacktip sharks (Carcharhinus limbatus), also known as blacktip whalers in Australia.

A recently uploaded video on YouTube shows a father and son buying a shark from a beach-side vendor with the sole intent of releasing it to the wild. After the young boys pays for the shark his dad hauls it down to the shore to release it back into the sea. The boy’s motivation for releasing the shark was to help conserve the animals as he goes on to say that “everyone should save sharks” and “we shouldn’t kill them.”

According to the boy in the video, the shark was purchased for the equivalent of $35(US). Based on the smile on the boy’s face after the shark swims away, and the celebratory high-five, I’m guessing both father and son considered it money well spent.

The footage is followed up by some anti-finning imagery and some unreferenced shark attack and mortality statistics. Personally, I think the video works better without it, as it somewhat ruins the upbeat and positive nature of the earlier part of the video. Besides, the boy did a fine job getting his message across on his own…but that’s just my opinion.

Grant Johnson recently uploaded another shark-filled video to his YouTube channel. This one focuses on the lemon shark (Negaprion brevirostris) and was filmed off of Bimini, Bahamas. The video starts out with some footage of juvenile lemon sharks swimming among the mangroves. The setting later changes to deeper water to focus on larger adult lemon sharks.

UPDATE Jeffrey Gallant – GEERG (Greenland Shark and Elasmobranch Education and Research Group) has commented that this is more likely a southern sleeper shark (Somniosus antarcticus), and could also possibly be a Pacific sleeper shark (Somniosus pacificus). However, it is “virtually impossible” to tell based solely on imagery.

The crew aboard of the Stena DrillMAX caught some amazing footage earlier this month of what appears to be a large Greenland shark (Somniosus microcephalus) recorded at over 9,100′ (2,770m) deep. To give a frame of reference, the pipe seen in the background is approximately 5′ (1.5m) in diameter. The depth (in feet) can be seen on the video in the upper-right corner.

The footage was recorded by ROV (remotely operated vehicle) about 300 miles (400km) off the coast of Brazil on February 11, 2012.

The Florida Museum of Natural History notes that a Greenland shark was recorded in 1988 at 7,218 feet (2,200 m) at the wreck of the SS Central America off Savannah, Georgia, USA. This is the greatest depth on record that I’ve been able to find, prior to the depth documented in the Stena DrillMAX video above which exceeds the 1988 recorded depth by about 1,900′ (over 500m).

If anyone has any other information about maximum recorded depths of sleeper sharks caught on film, please let me know, so I can pass it on to the Stena DrillMAX crew. Thanks!

San Diego’s CBS 8 recently interviewed Buck Elsmore, a stand-up paddle-boarder who was featured in a photo with the dorsal fin of white shark (Carcharodon carcharias). The photo was taken last fall off Encinitas’ Moonlight Beach.

Elsemore told Channel 8 that the shark swam near him at the surface for around a minute before descending back to deeper water.