Invasive SpeciesGreen crab

Carcinus maenas
FOUND by Supreme Seals
Cape Elizabeth
ID Confirmed
Quality checked by Mrs. Moniz
Peer reviewed by The Five Seconds
Field Notes
The time we were at Kettle Cove was 9:15-10:15 am. It was an ebb tide. An ebb tide is when the tide is going out. It was also low tide. The cloud coverage was 100%, which means you could not see the sky it was all clouds. The air temperature was 62 F, and it was pretty chilly, mixed with a small amount of precipitation. It was very windy, and it was 21 mile per hour wind gusts. Low tide was 9:13am High tide is 3:24pm. There were lots of crabs and some sea potatoes, plus the beach had some sand and on each end of the beach were rocky cliffs. It was hard picking up the crab because they were very quick but also they would cling onto the seaweed and if you tried to pick it up they were stuck. Once you picked them up it was pretty easy taking photos of the specimen, for some reason the Green Crab we found was not aggressive when we picked it up, Green Crabs are known for being very feisty. The time we were at the beach it was very foggy as well, but later on in the day it was not.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
This is shaped like a pentagon which has five sides. All the other invasive crabs in Maine have square shaped shells, there are five spines on the outside of each eye and 3 spines in between each eye. These features help us know that this specimen is a Green Crab.
Photo of my evidence.
Showing how big and bulky the claw is helps us know that this is a Green Crab. You can see that the claw is bulky because of the disproportion from its claws to its legs. The claw and legs are also thin and pointed at the tips, which are qualities of the Green Crab.
Photo of my evidence.
The colors are a greenish-yellow-brownish color. The legs of this specimen are very thin and pointed at tips. There are also five spines on the outside of each eye. In addition, there are also 3 spines in between the eyes, and these are all qualities of the Green Crab.
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 43.561100 °
W -70.217500 °
Observation Site Information
A photo of our study site.
Coastal - Rocky intertidal
Trip Information
Kettle Cove
Trip date: 
Tue, 2017-10-24 09:30
Town or city: 
Cape Elizabeth
Type of investigation: 
Species Survey
Time of low tide: 
Tue, 2017-10-24 08:26


Very nice close up photos of this crab's key features!