Greetings, fellow ECOLOG-ers. I'm still chewing on the issue of the "invasiveness" of Orconectes rusticus, and am still seeking answers, references or guidance. I understand that the rusty is a high-energy crayfish who is a messy eater and a pushy neighbor. I am not trying to be a pain, I am just finding myself asking questions that I can't seem to find answers for. This species seems to be just doing what species do, surviving and adapting and expanding its range. From what I gather, nature doesn't "stay put." Nature, by its nature, changes.
I know that I want to read some of Darwin's explorations with seed viability and species transport. Someone have a title suggestion on that? Some of my questions include: 1) If rusty came to Vermont in bait buckets, did he come alone? Were there other species that were used as bait? 2) If rusty was NOT alone, why aren't the other species becoming a problem? 3) What eats them in their "native" range, and do those predators exist in the "invaded" areas? 4) Vermont has 5 species of crayfish, including virilis. Are virilis "native"? If so, is virilis competing with rusty anywhere that they are both newcomers? Virilis are considered "invasive" in many other areas ~ why aren't they giving the rusties a run for their money? 5) Since Vermont only has 5 species of crayfish, it has been suggested that rusty has less competition than in, say, Tennesee, which has over 70 species. But let's look at population densities, not number of species. If a given square mile of stream in Vermont is home to (random number pulled out of my left ear) 500 individual crayfish, what happens when rusty comes calling? Does the rusty out-eat and out-compete and out-breed all the other individuals? Does he then reproduce like mad, crawl out and take over all other streams and lakes, and then...what? Does the rusty population crash because the streams can't support that many hungry crawdads, or does the local fish population adapt to eat them? Can we even make this sort of guess, based on the mere 40 or 50 years that rusty has been on the move? Thank you very much for any suggested reading or references you may have to offer. Sincerely, Kelly Stettner, Director
