~Ecology & Effects of the Invasive Crab, Hemigrapsus sanguineus~

I've been working with Unity students to study the potential effects of the Asian Shore Crab, an invasive species that arrived on the East coast (in NJ) in the late 1980's and has been spreading north and south.  The crab recently invaded Maine and we are examining an area, the Schoodic Peninsula, that is on the cusp of the invasion. 

During Summer 2006, we surveyed the current resident Green Crab (Carcinus maenas) population for distribution, size, sex, and physical damage.  We also surveyed the current mussel (Mytilus edulis) population.  Monitoring of the peninsula will continue through the invasion of H. sanguineus to quantify its effects on the competitor Green Crab and the mussel prey.

Hemigrapsus sanguineus photo by David Delaney	A tagged Carcinus maenas
Unity students, Meg & Alyssa looking for crabs along a transect	Meg & Alyssa recording data on crabs
More Unity Students assisting in 2007        Mallory, Lon, & Chanel	Lon searching in 2007 at Coitus Cove
Addie crab hunting in 2007 at Coitus Cove	Lon & Addie taking data on crabs found
Summer 2008 - Gretchen Legler's Creative Writing class from University of Maine - Farmington helped out with crab surveys.  Above: Ellen measures a tiny green crab.  Above right: Pam, Abe, and teaching assistant Lee work on the transect.  Right: Pam's drawing of a quadrat along the transect.

  A component of this project is to involve the public in the monitoring effort.  To help get the public involved, we made a poster that is displayed by Acadia National Park with important information about invasive species, crab natural history, current data, and how to identify and report Hemigrapsus sanguineus.   Poster (in Powerpoint)