Invasive Chinese mitten crab discovered in Hudson River BY JILL BRYCE Gazette Reporter
When Tom Lake was on the Hudson River in June he netted a creature that caught his eye. It was a Chinese mitten crab. It was the first and so far only one caught in the Hudson River, and its presence is worrying people who watch the river. It was caught near the Tappan Zee Bridge, between Westchester and Rockland counties. Lake, an estuary naturalist, recognized it as something he had never seen before in the Hudson. “With mittenlike appendages you notice the Chinese mitten crab right away,” said Steve Sanford, chief of the bureau of habitat for the state Department of Environmental Conservation. “It’s the only one we have found in the Hudson River and we hope it stays that way,” he said. Although only one has been found, it may indicate there is an established population of Chinese mitten crabs in the river and they may be reproducing, said Troy Weldy, director of ecological management for the Nature Conservancy. DEC is keeping a close eye on the new invader with a strict monitoring program. Experts are concerned about this non-native species from East Asia because it has caused major damage in Europe and in the San Francisco Bay, where the crabs have had devastating impacts on water engineering projects and clogged fish salvage facilities and fish passageways, said Weldy. According to DEC, a dozen of the crabs have been reported in the Great Lakes–St. Lawrence system since 1965; although a population has not established in that system, more frequent sightings since 2004 have raised concerns. Weldy said the Chinese mitten crabs represent a threat to various fish eggs and larvae because they are voracious predators but not picky eaters. “We are not sure if they will impact eel and sturgeon,” he said. With non-native species, it’s never clear what the creature will do or the dangers it presents. Sanford said the Chinese mitten crab may compete with the native blue crab in the Hudson River. Weldy said it could also impact the fiddler crab population, which occupies the same habitat in the Hudson River. It’s important to implement an early detection/rapid response approach and eradicate the crab and reduce its impacts on fisheries and natives species in the Hudson River and on water and electric facilities on the river, said Weldy. The Chinese mitten crabs are found in fresh water and salt water. They are walking crabs that can emerge from the water to move upstream of barriers and are capable of moving several hundred miles upstream from saltwater. They spend most of their lives in freshwater rivers, migrating to brackish or salt water to reproduce. The young move upstream, sometimes spending two to five years in fresh water. There are no native freshwater crabs in North America. They tend to stay on the river bottom and burrow a lot, so they can also undermine and destabilize river banks, which they have done on the West Coast. Their burrowing habits may threaten stream bank and earthen dam stability and promote erosion and habitat loss, said Sanford. “We don’t know what they will do and we don’t want to find out,” he said. It’s not entirely certain how the mitten crab (also known as Eriocheir sinensis) got here, but experts believe ship ballast water and live release are the two most likely means. Recent legislation passed by the New York state Senate and Assembly would create a list of species that would not be allowed to be sold in New York. Groups like the Nature Conservancy and DEC would come up with recommendations about what species to regulate, such as the Chinese mitten crab. The Chinese mitten crab is sold in Asian food markets and there is some speculation this is how it could introduce itself into the Hudson River. A recent study found one new species every six months within the Great Lakes systems, which is probably because it is a high commercial traffic area for shipping industry, said Weldy. The concern is that the steady increase in non-native, invasive species is due to increasing international trade. Weldy said it’s one reason why people should buy locally and support local producers. Around the state, groups called PRISMs — or Partners for Regional Invasive Species Management — are forming. The goal of such groups is to teach the public more about these invasive species and provide a rapid response to the invasive species when they are found. The Chinese mitten crab’s claws are equal size with white tips and hair. The shell is up to 4 inches wide, is light brown to olive color, and it has eight sharp pointed walking legs and no swimming legs. If someone catches one, they should not release it into the water, but keep it and freeze it, noting the date and location where it was caught. If possible, take a photo and e-mail it to SERCMittenCrab@si. edu for identification. The Mitten Crab Network, a partnership among several state, federal and research organizations, is collecting data to determine the abundance and distribution of this species. The DEC’s Division of Fish, Wildlife and Marine Resources will collect and hold specimens for genetics testing to pinpoint the origin of those caught in the Hudson River. The DEC is seeking the public’s assistance in collecting any Chinese mitten crab specimens that may exist. Anyone who collects and possesses a Chinese mitten crab to turn it over to DEC will not be prosecuted for possession or transport violations. But it must be turned over to DEC within 48 hours. Anyone who catches one in the Hudson River north of the George Washington Bridge is asked to contact Mark Dufour of the state Division of Fish, Wildlife and Marine Resources Hudson River Fisheries Unit at 845-256-3171.
Oh come on....you guys/girls have just too much time on your hands!
When the INSANE are running the ASYLUM In individuals, insanity is rare; but in groups, parties, nations and epochs, it is the rule. -- Friedrich Nietzsche
“How fortunate for those in power that people never think.” Adolph Hitler
When the INSANE are running the ASYLUM In individuals, insanity is rare; but in groups, parties, nations and epochs, it is the rule. -- Friedrich Nietzsche
“How fortunate for those in power that people never think.” Adolph Hitler
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