By Evan Cox, Restoration Assistant at Kankakee Sands
Crayfish are the freshwater cousins of lobsters living in Newton County! Commonly fans of rocky stream bottoms, many live in our sandy ditches or ponds, munching on vegetation and whatever else they can scavenge.
Crayfish are sometimes called mudbugs, which refers to their common habitat. We have several different varieties in our sandy soils. If you take a short trip to a slough or the prairie at Kankakee Sands, look for evidence of the painted hand mudbug, the digger, prairie, or calico crayfishes. All are around 3-4 inches from head to tail as adults, but they rarely leave their burrows unless to hunt.
A major species in the Great Lakes region is the northern clearwater crayfish (Orconectes propinquus). It will be found where the water is low in silt, which helps these visual hunters see their next meal. For this reason, expect to find them in rocky streams with stones up to a foot across one of their favorite hiding spots.
If reading this makes you hungry, I've got info on the right species. The red swamp crayfish (Procambarus clarkii) is the well-known behemoth from down south and now famous worldwide. Many have escaped the cooking pot, however, and can be found as far as Africa and Northern Europe.
What they consume is an open buffet ranging from fresh catches to decaying plant matter. They catch their prey with raw speed and grip from their powerful pincers. While they can be capable of grabbing prey as agile as minnows, a nip from one wouldn't break our skin, so consider them a friend.
Ranging from 2 to 5 inches as adults, red swamp crayfish can be found in many ponds, streams, and seasonal wetlands in prairies. They can be seen in shallow pools eating vegetation or other small invertebrates during early summer days.
The red swamp crayfish return to their burrows made of soft mud during the cooler months and at night. The holes they leave behind are what make them so hard to find, but these holes later become habitat for other parts of the food web, while also promoting water filtration. That service makes them a crucial element of our ecosystem, in addition to being the prey of many awesome species like predatory fish, otters and great blue heron.
Due to the very selective habitats they occupy, many species of crayfish are vulnerable to low populations. Their tendency to be well burrowed in soil or at the bottom of lakes makes them harder to study, but we know of their many benefits and know they are the coolest crustaceans that we have right here around us.
The Nature Conservancy's Kankakee Sands of Indiana and Illinois is 10,000 acres of prairie and savanna habitat in Northwest Indiana and Northeast Illinois, open every day of the year for public enjoyment. For more information visit www.nature.org/KankakeeSands or call the office at 219-285-2184.
Evan Cox is a seasonal Restoration Assistant at Kankakee Sands this year. Coming from the Bay State, he has graduated from University of Massachusetts with a degree in Environmental Design focusing on restoration of natural water systems. Working in and exploring the wet prairies at the preserve is what he does every day, and he loves it.