Shark beachings puzzle experts

  • Aug. 27, 2003 7:00 a.m.

Soupfin sharks-which can grow up to 2.5 metres or 7-feet in length- are washing up on the beaches of Tlell, but no one knows why.
Four have been found so far, two just south of Dress for Les and two near the mouth of the Tlell River, according to Janet Gray of Tlell who found all four.
The sharks began to appear about a week ago, and Ms Gray has learned from other islanders that this has happened in the past, in the same area. As well, there were reports last week of a shark or sharks in the Skidegate area.
While scientists are puzzled about why sharks would beach themselves, it is not unheard of that they do. As well, the sharks are not dangerous to humans, according to Jackie King, research scientist with the Pacific Biological Station.
Dr. Tom Reimchen of the University of Victoria lived in Tlell at one time, and he recalls seeing soupfin sharks swimming in shallows every year he was here. He speculates this may not be a simple beaching, but part of a shark behaviour that is not yet understood by scientists.
Soupfin, also known as Tope, sharks are found world wide in warm and cool waters. Along the pacific coast of North America, they range from BC to Peru and Chile, says Ms King.
These sharks are bottom dwellers and do not go deeper than about 450 m., preferring bays and canyons. They eat a variety of prey including hake, herring, crab and squid. Not much is known about their life cycle, says Ms King, but like all sharks, they are slow growing, and slow to reproduce. A female will give birth to between 6 and 45 young (called ‘pups’) per year. Sharks can live between 35 to 100 years depending on the species, but it’s not clear how long these sharks live. They have a distinctive tail fin designed to help them swim quickly. Scientists do know that they can travel up to 50 km in a day.
At one time, BC had a commercial fishery for soupfin sharks, with the fins dried and sold to Asia and the livers used to produce vitamins. However, the fishery stopped in the 1930’s after the creation of synthetic vitamins.