"A Warming Threat to Maine’s Lobsters"

"The water in the Gulf of Maine is warming rapidly, a change that could bring a once-rare lobster disease further north."

"In 2012, on the coast of Maine, lobstermen started showing up at Samuel Belknap’s dock with lobsters whose shells were covered in lesions. The shellfish were suffering from “epizootic shell disease,” a mysterious affliction that, in the worst cases, makes it look like “someone took battery acid and poured it on the lobster,” says lobster biologist Kathleen Reardon.

Belknap had grown up around lobsters, working as the skipper of a lobster boat, then as a dock boy, and later as the operator of his family’s dock in Bristol, Maine. The appearance of the disease left him both concerned and intrigued. It’s part of what inspired him to start a PhD program at the University of Maine, where he studies the ways shell disease and climate change may affect the lobster industry.

Right now, shell disease is rare in the Gulf of Maine. Only about one in every 200 lobsters is afflicted. Ultimately, the disease seems to be caused by bacterial communities, most notably the bacterium Aquimarina homaria. But this bacterium is naturally present on the lobsters’ shells, so now the search is on for the disease’s penultimate cause. The running hypothesis is that lobsters become susceptible when they’re stressed and their immune systems are compromised. One major cause of stress? High water temperatures."

Geoffrey Giller reports for Hakai magazine March 31, 2016.