Native SpeciesRock crab

Cancer irroratus
FOUND by Fibssully
Cape Elizabeth
ID Confirmed
Quality checked by Ms. Fanning
Peer reviewed by The Carolina Crustaceans
Field Notes
It was very cloudy and abnormally warm at Kettle Cove on October 24th, 2017. The clouds weren’t white, it was a dark gray like it was about to rain. The rocks were super slick, I even slipped on one. For everyone, it seemed pretty difficult to find a species. The sun was barely showing through the thick layer of clouds. We were collecting data so we can submit an Identification sheet to the Gulf of Maine Research Institute. This helps the scientists find the species they are looking for, such as the Rock Crab, and to get information about them.
A sketch of our study site.
Supporting Evidence
Photo of my evidence.
This is the Rock Crab because the crab has more than six spines. Looking at the carapace (shell), I saw that it had about 8-10 spines on each side. The spines went from the eyes to the side of the shell. The shell was about the size of my hand. It was about 13 centimeters long from side to side of the shell.
Photo of my evidence.
This is the rock crab because the claws are very sharp and thick. The rock crab is most commonly confused with the Jonah Crab. A way to tell the difference is by looking at their claws. The Jonah Crab claws are very bulky compared to the Rock Crab, yet they have a similar thickness. Here in this picture, the claws seem very compact, but still pretty thick, therefore, it is a Rock Crab.
Photo of my evidence.
This is the rock crab because it has a reddish-brown color on its shell. Green Crabs have a more greenish color, and Jonah Crabs have a light orange-light red color. Therefore it appears that the crab in the picture is a Rock crab because of its reddish brown color.
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Scientific name:
Cancer irroratus
Common name:
Rock crab
Sampling method: 
Just looking around
Photo of our sampling method.
Place Studied
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Map this species
N 43.561321 °
W -70.217890 °
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 this crab!