One of my favorite nature adventures to go on with my students, scouts and campers is to the edge of the Passaic River in search for crayfish aka mudbugs! It offers a fun, exciting, hands-on challenge that turns into an interesting educational opportunity. Students are fascinated by these crustaceans that breath through feather-like gills and act as the scavenging clean-up crew on the river bottom.
We scooped with big nets into the substrate and pulled up a mix of mud, leaves, clams, sunfish and crayfish. The crayfish are collected, observed, identified and released. A ziplock bag allows for easy viewing and portability out in the swamp. Those that returned to the lab for temporary study survive extremely well with a bubbling air pump while under observation.
At the Passaic river the primary catch I believe is the Rusty Crayfish, an invasive species native to the Ohio River valley which, if left unchecked, could out-compete the two native species, spiny creek crayfish and the Appalachian brook crayfish. It’s likely been introduced as fishing bait and it’s generalist nature allows it to survive in a variety of aquatic habitats but it does not burrow and is highly susceptible to predation by species like the Large Mouth Bass or American Eel.
The New Jersey Division of Fish and Wildlife Endangered & Nongame Species Program put out a report in 2010 on crayfish here.
I’ve also had success at a variety of locations with store purchased traps and home-made traps made of bottles with the top half inverted. Another quick trick is simply tying a chicken wing bone or piece of jerky to a string and letting them clamp on. Once clamped on you can slowly retrieve them as they are quite resistant to letting go when they have a tasty morsel in claw.
David Alexander is author of the Buzz Into Action & Hop Into Action Science Curricula. He is passionate about making nature accessible to people and wildlife. You can follow him at www.natureintoaction.com