Thursday, April 24, 2014

Baby Lobsters Are Disappearing, And Warming Oceans May Be To Blame


In this June 2007 file photo, a scientist holds a juvenile lobster while doing research on Orr’s Island in Harpswell, Maine.

Baby Lobsters Are Disappearing, And Warming Oceans May Be To Blame
EMILY ATKIN, APRIL 24, 2014 thinkprogress.org

It might be time to put away the butter.

Lobsters may be tough to come by in the coming years, according to a Tuesday report from the Associated Press. That report cited a University of Maine study showing that the number of baby lobsters settling off the state’s coast has declined by more than half from their 2007 levels.

Eight years is the amount of time a baby lobster takes to mature to legal harvesting size, so the real dinner table impacts would not likely be felt for at least some time.

As for the cause of this decline, the AP interviewed scientists who cited rising ocean temperature as a distinct possibility, though it failed to make the connection of warming oceans to man-made climate change. Rick Wahle, a marine ecologist at the University, cited rising ocean surface temperatures of .26 degrees Celsius per year since 2004, a dramatic increase from the .026 degree Celsius average increase Wahle was seeing each year since 1982.

Other possibilities for the decline include pollution, atmospheric condition, changes in predation, and availability of food, the report said — still not mentioning any of these elements’ potential connection to human-caused climate change.



The connection is pretty simple. Oceans are extremely sensitive to climate change, more so than the actual atmosphere. Indeed, more than 90 percent of global warming goes into heating the oceans, while less than three percent goes into heating the atmosphere. A good illustration of those findings can be seen in this 2011 study from Dr. John A. Church, the co-convening lead author for the IPCC Third Assessment Report’s chapter on sea level rise. A chart from that study is shown to the right.

Because lobsters are cold-blooded, they have to use more energy to breathe when the water around them gets warm. Breathing places more stress on the lobster, and may make it more susceptible to pathogens, the International Business Times notes. Climate-driven warming in gulf of Maine waters may also increase the prevalence of “lobster shell disease,” an unsightly sickness which stresses the lobster often leading to death, according to a study from the New England Aquarium.

As of now, though, harvests of full-grown lobsters are at an all-time high — which, ironically, is also due to warming waters, Stenck told ThinkProgress back in August. But as the Gulf continues to warm, the results won’t be as fruitful.

“We’re getting closer and closer to that point where the temperature is just too stressful for them, their immune system is compromised and it’s all over,” he said.

In anticipation of a decline, scientists in Maine are now competing for a share of $11 million of NASA grant money in hopes of creating a real-time lobster distribution monitoring system. That system will use satellite data and observations from fishermen and researchers to create an online map showing where and when lobsters and other key marine species can be found, taking pressure off fishery managers that in the past had to rely on historical catch data to plan for the upcoming season.

Lobsters make up 80 percent of the value of Maine’s fisheries, supporting not only fishermen, but boat builders, mechanics, bait sellers and the local tourist industry. The economies of the northernmost counties in Maine are 90 percent dependent on lobstering.

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