Tuesday, August 19, 2008
Greenland sharks in the St. Lawrence
Pierre Séguin and I just returned from a week in the St. Lawrence filming Greenland sharks for a season 2 episode of Jonathan Bird's Blue World. There is a place where for no reason anyone can explain, for the past 5 years, Greenland sharks have come into diving depths and approached divers without chum....apparently out of curiousity. It has scared the pants off of a bunch of divers! The water is normally about 39 degrees there at the warmest...so this is about the warmest water that these normally-arctic sharks are found in.
We planned to go last year, but the sharks showed up late, so our July trip was cancelled. This year they showed up early (June) and there were a lot of sharks....until we were scheduled to go (of course!) There has been a ton of rain this summer and as a result, the water is warmer than usual because the currents shifted. We decided to go anyway since a friend of Pierre's had offered to let us shoot aerials from his very cool helicopter. After 4 days of diving, we got two encounters....both very deep, where we could find cold enough water. We're hoping to go back in a few weeks, and hoping the currents return to normal along with the temperature. I never thought I would complain about water that is warmer than usual, but if you want Greenland sharks, you definitely don't want warm water.
It was very spooky diving that deep up there. The runoff from the rivers creates a tea-colored surface layer of fresh water that blocks all the light (viz about 3 feet). You go below it to get into colder, clearer water (viz about 15 feet). It's literally as dark as night....like a twilight dive. You can barely see anything. Then big sharks come slowly out of the blackness. I was deep, suffering from narcosis, tunnel vision, freezing my butt off, and chasing 12 foot sharks.
Cool stuff if you ask me!!
The image is a frame-grab from video of a shark filmed at 130 feet.
Posted by About Blue World at 12:28 PM