What is a Crayfish Mud Chimney?

This past week a few WLS staff members conducted various field work in Texas.  Throughout the trip we stumbled upon several Crayfish Chimneys. What are Crayfish chimneys you might ask? They are small mounds of dirt that Crayfish pile up while making tunnels. Crayfish are an aquatic species, but there are a few burrowing or terrestrial species. These burrowing crayfish use gills to extract oxygen from water, yet they spend most of their lives on land.  They dig burrows down to ground water in order to have a source of oxygen. This is why they are found around poorly drained soils near streams. When constructing their tunnels they throw mud around the exit hole.  A chimney can range anywhere from 3 to 8 inches.  Crayfish play an important role in our aquatic and terrestrial ecosystems, they are a source of food for many animals as well as consumers of plant and animal material.