Mitten crabs (Eriocheir sinensis), native to eastern Asia, have been introduced to the east coast of the U.S., including in the Hudson River Estuary in New York. Non-native species can cause severe ecological and economic damage once they establish large breeding populations. Early detection and rapid response efforts are necessary to mitigate potential negative impacts. DEC needs your help to be on the lookout and report sightings to firstname.lastname@example.org with the date, location, and photograph, if possible.
You can also report observations of non-native species to iMapInvasives using either the free mobile app or online using your computer or mobile device: www.nyimapinvasives.org
Mitten crabs are catadromous, which means they reproduce in estuarine and marine environments but return to freshwater environments to complete the remainder of their life cycle. Adult mitten crabs migrate downstream in late summer and fall to more salty marine environments to spawn. Juveniles with carapace widths >1 inch and adults can be identified by their claws, which are white-tipped and have dense patches of hair.
If caught, mitten crabs should not be returned to the water.