The United Nations Intergovernmental Panel on Climate Change has predicted that the Gulf of Maine waters will increase 5 degrees F. by 2100 and Maine’s lobsters may not be able to survive it.
In a study published in ICES Journal of Marine Sciences, researchers from the University of Maine Darling Marine Center (DMC) and Bigelow Laboratory for Ocean Science show how an increase of ocean waters would affect lobster development, with results that could be bad news for lobsters, their ecosystems, and the economy.
"They developed twice as fast as they did in the current temperature of 16 C (61 F.), and they had noticeably lower survival," Jesica Waller, a graduate student at the DMC and lead author of the study, told Science Daily. "Really only a handful made it to the last larval stage. We noticed it right from the start. We saw more dead larvae in the tank."
The researches raised more that 3,000 lobster larvae to observe the effect ocean warming and acidification had on the development of larvae and baby lobsters. Before the lobsters starting dying off, the researchers took daily measurements to assess development, size, feeding rate, and swimming speed.
While the temperature increase caused the larvae to develop too quickly and die, the acidification did not affect the lobsters’ survival rate.
"This is the type of work that really needs to be done," Michael Tlusty, an ocean scientist with the Anderson Cabot Center at the New England Aquarium, who was not affiliated with the study, told the Associated Press. "The oceans are not changing one parameter at a time."
An environmental change that effects lobsters will also have repercussions throughout the rest of the ecosystem. Other organisms will likely also be affected by temperature or acidity changes, and if lobsters are removed from the food web, there will be consequences for other species living in the ecosystem.
Despite all this, the lobster industry is booming.
With a steady demand in the states and a growing popularity in Asia, the price of lobster has remained consistently high. And US fishermen, who have caught more than 100 million pounds of lobster each year for seven straight years, are more than prepared to meet the demand.
Although rising ocean temperatures have not yet affected the big picture of the lobster industry, pockets of the southern lobster fishery area give a glimpse of what is to come when the Gulf of Maine warms up.
"There has been a near total collapse in Rhode Island, the southern end of the fishery, and we know our waters are getting warmer," Ms. Waller said. "We are hoping this research can be a jumping off point for more research into how lobsters might do over the next century."
Cape Cod has seen a similar decline in its lobster industry. Twenty years ago the Cape produced 22 million pounds of lobster each year, but by 2013 that number had dwindled to just 3.3 million. This isn’t good news for Maine, where lobsters make up 80 percent of the state’s fishing industry upon which the economy is dependent.
"It's critical to know how climate change will affect the future of our most important fishery," Rick Wahle, UMaine research professor and co-author of the paper, told Science Daily.
Material from the Associated Press contributed to this report.