Invasive SpeciesAsian shore crab

Hemigrapsus sanguineus
FOUND by FireBreathingDuckies
ID Confirmed
Quality checked by Go science
Peer reviewed by PPJ
Field Notes
I am happy because we found a Asian shore crab and lots of green crabs, mainly smaller ones. In the beginning of our search we found a baby lobster in our trap that we put out for crabs. I see, hear, and smell crabs, rocks, water, sky, lots of seaweed, traps, lobster, trees, and logs. I hear waves crashing over the the rocks and the voices of others around me. I smell the salt water along with fishy smells coming from the seaweed and water. I am surprised by what I found or didn’t find because there is such a change in the ocean environment. I am surprised that we did not find more Asian shore crabs. I am also surprised that that we did not find any Chinese mitten crabs. One of the things we wondered is why our group did not find many green crabs, but many other groups found lots of them. There was a lot of green crabs in the trap that we pulled out of the ocean. I am also wondering why we did not find many Asian shore crabs on the shore or in the shallow water. The longitude and latitude of the area we studied is 43.785202 and -69.722424. The temperature at reid state park is 60 degrees fahrenheit, we did our studies in the mid day. The day we went was October 27, 2017.
Supporting Evidence
Photo of my evidence.
The Asian shore crab has white and black bands on its legs, and the crab is greenish.
Photo of my evidence.
The Asian shore crab is a female because the bottom of the crab near the legs is rounded, which means it is a female because that is where she holds her eggs.
Photo of my evidence.
The Asian shore crab has three spines on each side of the eyes and this crab is also square shaped.
Species Observation: Species Looked For
Did you find it?: 
I think I found it
Scientific name:
Hemigrapsus sanguineus
Common name:
Asian shore crab
Sampling method: 
Quadrat (user-placement)
Photo of our sampling method.
Place Studied
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Map this species
N 43.785202 °
W -69.722424 °
Observation Site Information
A photo of our study site.
Coastal - Rocky intertidal
Trip Information
Reid State Park river
Trip date: 
Fri, 2017-10-27 10:00
Town or city: 
Type of investigation: 
Species Survey
Time of low tide: 
Thu, 2017-10-26 11:08


I love your group's name! Your field notes were detailed and I could picture, smell, and hear the spot in my mind.
Your photos and descriptions demonstrate that you found the Asian shore crab.
Did you look for the green crabs on the shore, or just in the trap? Where did you find the Asian shore crab (under seaweed? in a tidepool? and how many did you find?

Nice job on the id and fantastic, clear pictures!

Hi FireBreathingDuckies,

Great photos! Your field notes are interesting, too. Why do you think that there were more green crabs in some locations than others?

We noticed that the coordinates that you wrote in your field notes did not match the coordinates on the map, so we fixed the map for you. Now it clearly shows that you were investigating at Reid State Park river.

Keep up the great work!

-The VS Team-