Pond Boss Forums STOCKING A NEW POND Raising Forage and Bait What type of crayfish is this

The crayfish I have seen tend to get a lot more darker and colorful as they get older and mature. I've also noticed if they run out of water and are forced to survive on the remnants of what water is left they tend to darken.

The ones I have found in the creek this spring which I assume to be Northern's (but not certain about this) the 4-5" ones are very dark color and the small ones (from a quarter inch to 2") are much lighter in color.

Just my observation. They could be different species for all I know though.