Some folks are quick to give sharks a bad rep without considering their importance as top feeders in the marine food web. But when we remove these so-called lions of the ocean from their habitat through shark-finning and bycatch, it doesn’t take long for the rest of the food web to feel the effects. Chew on this:
In 2004, North Carolina’s century-old bay scallop fishery effectively ended because too few scallops survived into the autumn to sustain fishing, according to a report published in Science last month.
The culprit? Rays. Vast increases in the numbers of rays, which eat scallops. The rays have been decimating the young scallops before they could grow to commercial size.
So where do the sharks come in?
Sharks eat rays. And since the start of careful annual shark counting in North Carolina in 1972, there have been astonishing declines in the numbers of big sharks there. Indeed, Science reported, data “demonstrates sufficiently large declines in great sharks to imply their likely functional elimination.” Since 1972, sandbar shark populations are down 87 percent; blacktips, 93 percent; tigers, 97 percent; scalloped hammerheads, 98 percent; and bull, dusky and smooth hammerheads, 99 percent.
The Science study of scallops and sharks was the last article published by Ransom Myers, world-renowned marine biologist and member of Oceana‘s Science Advisory Board, who died recently at the age of 54.
