Invasive SpeciesGreen crab

Carcinus maenas
FOUND by jjjc
Cape Elizabeth Maine
ID Confirmed
Quality checked by pp
Peer reviewed by am
Field Notes
The weather at Crescent Beach was about 50°F and cloudy with a little bit of sunshine. It had been raining a lot in the past couple days, so the rain might have affected the look or the placement of the Green Crab. I found it difficult to find the species that I was looking for. I was looking mostly under rocks and in small crevices. It turns out they'll stay anywhere where there it is wet and rugged terrain. You'll see them around rocks, seaweed, and sandy water. I was surprised by all of the different types of crab species, and how they look so alike, but have different characteristics.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
The size of our green crab is about an inch long. It's is a little short for an adult green crab, but my assumption is that it's just a baby. According to the Vital Signs ID sheets, the average size of a Green Crab is about 8-9 centimeter wide. This is definitely a Green Crab because the Vital Signs ID sheet told us that the other crabs in the area are have way smaller shells.
Photo of my evidence.
This Green Crab that we identified had five spines to the side of each eye. The Vital Signs I.D. sheet told me the amount of spines on all common crabs in our searching area. So that's how I know that this is the Green Crab and not a different crab species.
Photo of my evidence.
This Green Crab that we have found is green. I know that this is the Green Crab because in its common name it states that it is a Green Crab. I think this is a fairly young crab because it's green. The ID sheets that we examined said that only 5% of adult Green Crabs are actually green. I know that this is a Green Crab because it has a distinctive green that cannot be mistaken.
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 43.562011 °
W -70.219588 °
Observation Site Information
A photo of our study site.
Coastal - Beach or dune
Trip Information
Kettle Cove (CEMS 7th Grade)
Trip date: 
Tue, 2014-10-28 09:22
Town or city: 
Cape Elizabeth Maine
Type of investigation: 
Species Survey
Time of low tide: 
Tue, 2014-10-28 08:25
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