2016

The Crayfish of Nebraska

Steven C. Schainost
Nebraska Game and Parks Commission

https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1073&context=nebgamewhitepap

From page 59

Quote:
Northern crayfish will eat fish eggs and sac-fry. One study tested the impact of egg
predation of Northern crayfish on pumpkinseed(Lepomis gibbosus) and bluegill (Lepomis macrochirus) in ponds. In densely vegetated ponds, pumpkinseed had delayed reproduction and lower young-of-year biomass due to crayfish predation. In less vegetated ponds, crayfish prevented bluegill reproduction except in crayfish proof exclosures.


From page 13.

Quote:
Primary burrowers spend most of their adult lives living in a burrow. The Grassland
crayfish, Procambarus gracilis, is a primary
burrower and may spend 95% of its life in a
burrow. The Devil crayfish, Cambarus diogenes, is also a primary burrower spending 80-90% of its life in the burrow though adults or young can occasionally be found in open waters.


Quote:
Secondary burrowers dig burrows to escape
drying waterbodies or freezing weather. The Calico crayfish, Orconectes immunis, is a secondary burrower.


Quote:
Tertiary burrowers are crayfish that dig a burrow as a last resort and, even then, it is
not an extensive or deep burrow. The Northern crayfish, Orconectes virilis, is a tertiary burrower which often digs a shallow burrow beneath a rock during winter or during drought