Closures for Winter
December 2, 2013- Acadia is now in winter mode. Most of Park Loop Road, including Cadillac Mountain Road, is closed. Still open is the Ocean Drive section, from Schooner Head overlook to Otter Cliff Road, and Jordan Pond area via Jordan Pond Road. More »
Field Guide to Marine Invertebrates - Arthropods - Crustaceans
Cancer borealis ("Jonah crab") is found in the mid- to lower intertidal zone under algae and among rocks. This predator eats blue mussels and other invertebrates. The remains of this crab are often found in the upper intertidal zone, evidence of bird predation.
Carcinus maenas ("green crab") is found under algae and small rocks, and it eats other invertebrates in the mid- to lower intertidal zones. This crab is native to Europe and is an invasive species. The green crab is smaller than the Jonah crab.
Homarus americanus ("American lobster") is a bottom-dwelling predator and scavenger. The American lobster is found throughout the Gulf of Maine, where it is commercially important. The lobster is found in rocky, subtidal habitats but, rarely, can be observed in lower intertidal pools.
This herbivorous crustacean, an isopod, feeds on a variety of algae including large rockweeds (Ascophyllum, Fucus). It is common in the mid- and lower intertidal zones but is hard to see because its color usually matches the algae it is feeding on. This behavior helps it resist predation by fish. Individuals vary in color from yellow to brown to deep burgundy.
All photos by Sarah Hall, except for American lobster (NPS/Todd Edgar photo).
Did You Know?
Acadia National Park's carriage road system, built by John D. Rockefeller Jr., has been called “the finest example of broken stone roads designed for horse-drawn vehicles still extant in America.” Today, you can hike or bike 45 miles of these scenic carriage roads in the park.