The number of young lobsters is declining in the Gulf of Maine despite years of record-breaking harvests, a University of Maine marine scientist has warned.
Rick Wahle quantifies the population of baby lobsters in the gulf, a key lobster fishing area about the size of Wisconsin, at monitoring sites in New England and Canada every year. His American Lobster Settlement Index, released this month, shows monitoring sites from New Brunswick to Cape Cod had some of the lowest levels since the late 1990s or early 2000s.
The decline in baby lobsters represent an "early warning" of what might happen to the future of the lobster harvest, which is the source of a major fishery and a focus of the tourism industry in New England, Wahle said. Lobsters take several years to grow to legal harvesting size, so the drop in young lobsters would start to affect lobstermen in future years, he said.
"If we were to see a collapse in the lobster catch, it would mean that we're already seven to eight years into a decline in the population," Wahle said.
For over 10 years now, lobster egg production has been rising but the number of baby lobsters has been falling, Wahle said. Scientists and fishermen are working to better understand the changes in the lobster population and their potential ramifications for the environment and the economy.
Wahle said one factor could be a declining amount of a type of copepod that baby lobsters like to feed on. Another possibility is an increase in predators of young lobsters, he said. Wahle said scientists need to better understand those issues to help prepare for the future of the lobster fishery.
Maine accounts for the largest percentage of the U.S. lobster catch yearly, and the industry has been booming in recent years. The catch climbed to more than 130 million pounds last year, which was a record total according to state statistics that go back to the 19th century.
The total U.S. lobster catch was worth a record of more than $620 million in 2015, which is the most recent year for which statistics are available. It's a lifeblood industry in Maine, and Wahle cautioned that "a downward trend in lobster production could significantly impact the state's coastal economy in the future."
David Cousens, the president of the Maine Lobstermen's Association, agreed. He said he's concerned about the Maine lobster fishery going the way of the southern New England fishery, which scientists have said has faded in the face of warming ocean waters.
"It isn't encouraging. You've got to find out what's causing it if we're losing baby lobsters," Cousens said. "And we need to do as much as we can to slow down global warming. That is critical to our existence."
Wahle is co-chairing an international conference on lobster management this week in Portland. Environmental factors such as the impact of warming ocean waters on the lobster population are among the focuses of the event.
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