St. Pierre says he'll be working an area with abundant haddock, for instance, then the trawlers appear and the haddock are gone. Weiner said fishermen have also noticed the herring getting smaller, a possible sign that the older, larger herring have been fished to nearly nothing.
This evidence of a herring problem is mostly anecdotal, but Weiner says the decades of knowledge and observation from all corners of the industry can't be dismissed.
"The best available science in most of these fisheries is still pretty weak stuff," Weiner said.
The depletion of herring stocks could have numerous implications, fishermen and environmentalist say. Bait costs would rise for the region's lucrative lobster industry. Without herring to chase and eat, game and commercial fish could fade from inshore waters. Struggling species, such as cod, could fail to rebound without this key food.
"Herring are a vital food source for cod and many other species," said Jud Crawford of the Pew Environment Group. "It doesn't take a rocket scientist to get the idea that if you're pulling out one of the major food sources (for cod) ... you're at least decreasing the chances of recovery."
Regulators are now conducting a major assessment, expected to be completed this summer, which should answer key questions about herring's health.
In the meantime, the herring industry has anecdotal evidence of its own to counter critics. Tooley said reports of herring scarcity are just snapshots from people who don't track the fish for a living and see how plentiful it is.
Without hard evidence that shows otherwise, the industry isn't going to agree to being shut out of new areas, concede that long-used methods for weighing the catch are inaccurate or say the trawlers are harming other fish species.
But Tooley said the industry supports placing independent observers on every midwater trawler trip, to increase overall confidence in the fleet.
"We need to have a monitoring program that allows the fleet to operate without all this constant criticism," she said.
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