Invasive SpeciesGreen crab

Carcinus maenas
FOUND by Tasty tacos
Cape Elizabeth
ID Confirmed
Quality checked by Mrs moniz
Peer reviewed by Team AC
Field Notes
Field Notes: It was a sunny fall day as the bus pulled up to the rocky beach. Kids were pouring out of the buses like a flash flood after a severe rainstorm. I could see the ocean and seaweed, and the air was filled with a cacophony of seagull sounds. Above all the other smells the salty aroma wafted through the air. The rocks and seaweed covered the ground like leaves on the ground of a forest in Autumn. Tidal pools were scattered around the rocks, because it was low tide at Kettle Cove. I was surprised when we found the crab early on, as we had taken a little while to find one in the previous search.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
We think this crab is a Green Crab because it has 5 spines on the outside of each eye in between an eye and the side of the carapace. This picture of the crab we found has 5 spines outside of the eyes. An easy trick to help identify a Green Crab is its 5 spines; Green has 5 letters and Green Crab has 5 spines.
Photo of my evidence.
This crab also has a pentagonal shaped carapace, as does a Green Crab. Another trick you can use is a pentagon has 5 sides and Green has 5 letters. Another crab, the Asian Shore Crab has a square shaped carapace so this was not an Asian Shore Crab.
Photo of my evidence.
This crab has a white underbelly and skinny claws and legs with sharp tips. According to the Vital Signs identification sheet, so does the Green Crab. These skinny legs allow them to move very fast and aggressively.
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Scientific name:
Carcinus maenas
Common name:
Green crab
Sampling method: 
Just looking around
Photo of our sampling method.
Place Studied
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Map this species
N 43.561346 °
W -70.218747 °
Observation Site Information
A photo of our study site.
Coastal - Beach or dune
Trip Information
Kettle Cove Oct 2015
Trip date: 
Tue, 2015-10-20 07:40
Town or city: 
Cape Elizabeth
Type of investigation: 
Species Survey
Time of low tide: 


I really like the purple lines illustrating the key features of the crab. Well done!