Mission: Crayfish

Research Question


Where are Maine's native and invasive crayfish hiding?

You're invited

Dr Karen Wilson, University of Southern Maine, invites the Vital Signs community to join her statewide crayfish survey. She put her mission invite and instructions on VIDEO. Check it out!

Mission steps

1. Print the crayfish species ID card
2. Print a Freshwater Species & Habitat Survey datasheet
3. Set your trap or grab your kicknet
4. Go to your My Vital Signs page (link at top right) to add your "crayfish found" or "not found" observation
5. Check out Mission: Analysis to figure out how your observation fits and what it means

Orconectes virilis, native!

Why this Mission matters

Relatively little is documented on the whereabouts of native and invasive crayfish in Maine. Dr Karen Wilson is heading up a statewide crayfish survey to help determine population distribution. Invasive crayfish like the rusty crayfish pose a real threat to Maine’s native crayfish and trout populations.

Karen wants more!

In addition to publishing a Species & Habitat Survey, Karen requests:

  1. A male voucher specimen humanely dispatched by freezing, then sent to me still frozen or preserved in alcohol
  2. A simple description of habitat in your Field Notes: sand, muck, or cobble; pool, riffle, or lake
  3. A simple description of abundance in your Field Notes: Rare - hard to find, Common - found several easily, Abundant - nibbling toes!


Hi, I live on the Pleasant River in Gray and today I took my 6 year old son for a walk in the stream/river to catch critters. We brought a net and a bucket not knowing what we'd find and the crawfish were everywhere...some were quite large and about 8cm long. There are holes in the silt bottom of the stream all over the place. There are so many of them in there that I'm considering having a crawfish boil like I did when I lived in Mississippi, as they are similar in size to the Red Swamp Crayfish. I took a picture of our bucket with about 20 of them that we caught and I took a closeup of one of the larger ones. Is there a way I can send you a picture? They are on my phone so it is easy to email or text them. I can get more pics too if you're interested. Or if I can even find a way to post them to this site...the only reason I joined this site is because I Googled invasive crayfish species in Maine and your page came up. Hope to hear from you soon.



You can definitely post your observation to Vital Signs. The species expert will get a notification when you do. Here's a helpful how-to guide to help you: http://vitalsignsme.org/how-citizen-scientists-collect-data-and-put-it-w...

You will need an evidence photo, site photo, sampling method photo, and your location data. Once you have those things you can go to your "My Vital Signs" page (see the link in the top right?) and publish your data.

Thanks for sharing!

-The VS Team

My son and I would like to study crawfish in Northern Maine waters. How do we collect the voucher samples humanly for you? How do we send them to you?

We are excited to help you in your project.

Thank you.

Last summer I found 2 crayfish at a stream a few hundred feet from my house, but I'm not sure if they were invasive or not. I will look into it, though I haven't seen any more since.

i might do crayfish too

Hi, where have you found the crayfish in Maine?

Click on "Explore Data" and then do a Species Search for crayfish. If you click "Map It," you'll get a map of all the places where crayfish have been looked for in Maine.

Are you planning to add another crayfish observation to the map soon? Hope so!



im doing crayfish also.