ITHACA, N.Y. -- They're here.
Japanese shore crabs, a square-shaped crustacean that poses a direct threat to soft-shell (steamer) clams, mussels and lobsters, were discovered July 13 by Cornell University marine biologists in Owl's Head, Maine, on the shores of Penobscot Bay. The detection of this crab, which has the potential to hurt Maine's seafood industry, means that Penobscot Bay becomes the most-northern point along the Atlantic seaboard where these crabs have been found.
The Japanese shore crabs (Hemigrapsus sanguineus ), which feast voraciously on mussels, clams and other shellfish, were found at Crescent Beach in Owl's Head by Robin Hadlock Seeley, a marine biologist and an associate curator of Cornell's Malacology Collection, and Erin McDonald, a Cornell junior from New Hartford, N.Y.
Last summer Seeley was conducting her annual survey of the green crab, another invasive species, when she found the smaller purple crab in Casco Bay, Maine. The Japanese shore crabs, which already have invaded the waters of Chesapeake Bay, Long Island Sound, the Jersey shore and the coast of Massachusetts, were not expected to be found this far north so soon.
"The shock is that they've been in almost every place we've looked in Maine," Seeley said. "Anytime you have a new species which is a predator, you have cause for concern."
To find these crabs, the researchers had combed the southern shores of Penobscot Bay. The low tide on July 13 was at 7:45 a.m., which is when the researchers began inspecting Birch Point Beach in Owl's Head. After three hours they had found no Japanese shore crabs there.
However, the researchers continued their morning hunt. "We really didn't have much time left before high tide, but we wanted to make sure the crabs weren't this far north," said Seeley. With two hours until high tide, at about 11 a.m., they visited nearby Crescent Beach.