Invasive SpeciesGreen crab

Carcinus maenas
FOUND by The Flash
Cape Elizabeth
ID Confirmed
Quality checked by BirthdayBuddies828
Peer reviewed by
Field Notes
As the 7th grade at CEMS stepped off the busses at Kettle Cove people were shouting and giggling. The mist and wind created a slight chill that ran up and down the backs of the students. The gray sky was looming as waves of kids ran down the beach to start the search. There were kids running around and teachers shouting warnings about the slippery seaweed. The salty air was only 63° the wind was blowing 16 mph to the south. Clouds covered most of the sky. The low tide time was at 9:06 am and the high tide time was at 2:42 pm. It was a flood tide which means that it was in between high and low tide and the tide was coming in.
Supporting Evidence
Photo of my evidence.
We think we found the green crab because the green crab has pointy claws and so does this crab. The claws on this crab are sharp and the green crab's claws are also sharp.
Photo of my evidence.
We think we found the green crab because this crab shares the characteristics of a green crab. One of the characteristics that this crab and the green crab share is the shape of its carapace (outer shell). The green crab has a pentagon shaped carapace and this crab also has a pentagon shaped carapace. Another thing this crab has in common with the green crab is the five ridges that are on the side of its eyes (refer to blue arrows). This is not a different type of crab because it has 5 ridges and no other crabs in Maine have 5 ridges.
Photo of my evidence.
We think we found the green crab because this crab’s coloring is the same as a green crabs. Green crabs are brown and green and this crab has brown and green coloring. A way we can tell this is not a different type of crab is that no other crabs in Maine have green and brown shells.
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 43.561175 °
W -70.217571 °
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


Great work identifying the key characteristics fo this crab!