Flotsam & Jetsam

A Shark Movie for Idiots. While the film Sharknado is about as ridiculous as they come, we learned recently of a movie released last summer that must be the alltime worst shark movie, if not the all- time worst movie of any genre. In Avalanche Sharks, these puppies swim under the snow, with their dorsal fins aimed directly at skiers and snow bunnies in the hot tub. See the trailer at www.youtube.com/watch?v=sotQoOngYno. (Thanks to Ken Kurtis, owner of Reef Seekers in Beverly Hills, for the tip.)

Careless Divers Putting Coral at Risk. It's no secret that careless divers, especially those with cameras, can harm coral. A new study out of Hong Kong shows just how serious that harm can be. Chung Shan-shan, a professor of biology at Baptist University, found that more than 70 percent of divers came into contact with coral, potentially causing irreversible damage. Her study surveyed and observed 80 divers at dive sites near Hong Kong, and found that each touched coral 14.7 times on average in each dive. The majority of those were inexperienced or carrying cameras; contact was unintentional and mostly caused by their hands and fins. Nearly 40 percent of divers said they made contact with coral because they lost control of their buoyancy; 8.6 percent said they were taking pictures; and 6.2 percent just found the coral convenient to hold on to. Cameracarrying divers made contact an average of 23.8 times per dive, compared with 11.6 times for others.

Keep an Eye on Those Mantis Shrimp. In all likelihood, these crustaceans will have spotted you first. Their eyes are on stalks and can dart around. Humans use similar rapid eye movements to lock onto new objects and track them as they move. "But it was not clear whether the shrimp eye movements were anything to do with acquiring objects, or just repositioning the eyes," Justin Marshall of the University of Queensland in Australia told New Scientist. To find out, his team placed mantis shrimp in a perspex tube inside an aquarium, and suddenly introduced a small colored disc into their line of sight. A camera outside the aquarium filmed their eyes.The shrimp's fovea, the part of the eye with the highest resolution, focused on the disc, just like a primate. But while humans' rapid eye movements can sweep through a field of view at a rate of 250 degrees per second, the mantis shrimp's eyes are moving at up to twice that speed.

Freediver Hit-and-Run. Florida Fish and Wildlife investigators are looking into an boating hit-and-run incident about a mile off Palm Beach that left a freediver in serious condition. Jorge Caba had his dive flag and his properlymarked buoys deployed when he jumped off a boat to free dive near the Breakers in mid-January, but a boater ran him over near the surface and then took off. Caba had to have surgery for a broken pelvis and a gash on his leg. Jonathan Dickinson of the group Florida Freedivers told news station WPTV that freedivers need to keep an eye out for boaters, even if they are following all the rules. "When you are freediving, you don't have as much time. You are coming back to the surface because you are out of air. You don't always have time to stop, look, listen and wait."

The Wolf of Wall Street Can't Swim with the Sharks. While promoting his latest film, Leonardo DiCaprio says he is terrified of sharks after getting stuck in a cage with one. He told Ellen DeGeneres that a "gigantic great white" tried to attack him when a shark cage diving expedition went awry in South Africa in 2006, while he was on a break from filming Blood Diamond. "They actually said in 30 years this has never happened, but the tuna kind of got stuck on the top of the cage, and the great white leapt out and tried to bite it and went into the cage with me," he said. "Half of its body was in and out, and I flattened down at the bottom, and it chomped a few times but I survived it." He was invited on the expedition by a nonprofit devoted to shark protection, but he admitted it left him mentally scarred. "I don't want to discount their work because they're doing great stuff. But it was absolutely terrifying."