Pond dwelling crayfish adverse affects would primarily be more turbid water when the crayfish (crawdad) become very abundant as in a forage pond with no predators such as bass. Crayfish can get abundant enough that they denude all the vegetation except cattails. Sunfish will eat lots of the small crays less than 3/4-1". Papershell (aka calico crayfish) crays will not create long deep tunnels unless the water is almost all gone in the pond.
Papershells live primarily under flat objects (rocks, concrete, etc) and most of the time forage for food primarily at night, low light. Papershells have firm shells similar to all crayfish except when molting. I've caught 10" perch with 2.5" papershell in the stomach, thus the same would be true for 10" bass. The more cover available the more crays that will thrive in the pond which is basically the same with all wild animals. It takes a LOT of rocky cover to have abundant crays in a bass predator pond; plus the adult sunfish will eat the young small crays. One will not get a very big population of crayfish in the relatively small rock pile of a 1/3 ac to 1 ac pond shown in the RAH picture above. The more cover available the more animals that will survive. Not many pheasants, quail, and rabbits, live in barren, sparsely vegetated fields. Cover is very important for raising forage (prey) with predators.
Papershells (Orconectes immunis) in my experience do not crawl out of the pond and dig/build the mud chimney mounds on top of the tunnel. Chimney building, burrowing crayfish are a different genus (Cambarus, Procambarus) group of crayfish. Papershells and most all other species of crayfish live in streams as do almost all crayfish species. Papershell and several other species are well adapted to live in ponds.
Many fish farms have overabundant nuisance crayfish that they sell collected from their ponds. Very few farms sell pure strain/specie of Papershell (Orconectes immunis). Common in most fish farms are White River Crayfish, Red Swamp crayfish(Procambarus) , Northern Crayfish, and Rusty Crayfish. Three of these species all belong to the genus Orconectes; all are more aggressive and get larger and even quite a bit larger than the Papershell crayfish depending on the specie. Do your homework and due diligence. If the crayfish specie is not native to your locality it is considered an INVASIVE specie and almost always causes harm to the native crayfish populations even to the point of displacing, 'killing out' the native species.
Last edited by Bill Cody; 03/10/20 08:47 PM.
