Originally Posted by anthropic
Eric, could crawfish help control excess bushy pondweed? Also, could they slow down LMB production? Like most pondmeisters, I have to harvest lots of LMB every year to keep things in balance..

Craws effect on fisheries depends on many factors including which species you add. Never add Rusty Craws IMO. My answer to OP assumed he had adult predators as he said it was a one year old pond with lots of forage. If not then my answer would change to much like Quater Acre's.

Craws will eat plants of most types as well as lots of other stuff including fish eggs. They can slow LMB reproduction a little but would have a bigger impact on BG reproduction. LMB are large enough to eat craws that move on their nest but BG can't eat adult craws. Like all things results depend on the location - it depends on numbers and facts.

From one Study;

Abstract.�We attempted to control a population of papershell crayfish (Orconectes immunis) in an 11-hectare fish-rearing impoundment in Jackson County, Wisconsin, by using traps and by stocking largemouth bass (Micropterus salmoides). Crayfish were harvested with traps during the summer of 1985, and the pond was stocked with 386 largemouth bass (mean weight, 1.1 kg) in spring 1986. The pond was drained in the fall of 1985 and 1986, and crayfish burrow counts were made to estimate the population. In 1985, we trapped more than 18,000 crayfish, of which 72% were adult males. Trapping had minor effect on the young-of-the-year crayfish. In 1986, the crayfish population was reduced by 98%, predation by largemouth bass being the probable major cause of the reduction.