|FYI — April 2003|
|By Brad Dunn|
Word With... Jim Leishman
In January researchers at the Dalhousie University in Halifax, Canada, reported that most North Atlantic shark populations have been cut in half over the past 15 years, with some species dwindling almost to the point of no return. Hammerheads, great whites, tigers and threshers are among those that have been most devastated by the heavy increase in longline, commercial fishing.
“This is a worldwide phenomenon,” reports Ransom Myers, a co-author of the study, in the journal Science. “We estimate that all recorded shark species, with the exception of makos, have declined by more than 50 percent in the past eight to 15 years.”
Research shows that in areas where longline fishermen relentlessly harvest tuna and swordfish, hammerheads have dropped by 89 percent, threshers by 80 percent, and blue sharks by 60 percent. Great whites, made famous in Jaws, have declined by 79 percent.
In addition to increased fishing, the drop in shark population reflects the species’ slow, almost mammal-like, reproduction cycles that cannot replace depleted numbers. “They are like humans,” Myers says. “They take a long time to mature and have relatively few babies. That makes them more vulnerable than other fish species.”
The researchers say that even minimal changes in commercial fishing practices would greatly help the sharks rebound. Because most species hunt and migrate at predictable times and places, scientists say fishermen could plan their harvests around them. They also urge international agencies to establish more refuges in the North Atlantic, where no fishing is permitted.
This article originally appeared in the March 2003 issue of Power & Motoryacht magazine.