Over the past two decades, lobster landings have increased more than five times with fishery landings topping over $300,000,000 annually in the U.S. Given that the lobster fishery now is a large percentage of the total fishery value of New England, understanding why landings have increased will be critical to sustaining this important fishery.
Scientists and fishermen have suggested several hypotheses to explain why lobster populations have increased recently. One possible explanation is that fishermen are subsidizing lobster populations with herring bait. Fishermen annually use 60,000 metric tons of herring to attract lobsters into fish traps. Surprisingly, lobster traps are not as efficient as we might think. A lobster trap video experiment revealed that 94% of the lobsters that entered the trap escaped it (Jury et al. 2001). However, scientists have yet to evaluate the importance of herring bait for lobster populations in the Gulf of Maine.
Image: Lobster traps are used to catch lobsters throughout coastal Maine. Only 6% of the lobsters that enter traps are caught.
Since 2002, we have been conducting research in collaboration with fishermen in mid and eastern portions of the coast of Maine and in New Brunswick, Canada to determine (a) how much does herring bait contribute to the diet of lobsters and (b) whether herring bait augments lobster growth.
Figure: Maine lobster landings have increased more than five times over the past two decades because both fishing effort and lobster populations have increased.