Originally Posted By: Lloyd3
I'm perplexed. I'm fairly certain northern Minnesota has both raptors and coyotes (and even wolves where I'm hunting). Heck, I've even personally seen at least two Fisher cats on the trails up there and yet...the birds seem to be doing quite well. I would venture to guess that West Nile is even up there as well. What am I missing here? I have read that certain species require a minimum population density to propagate successfully, a "tipping point" of sorts. Is that a possible explanation? I do know that Minnesota birds are the Canadian varient (Bonasa ????, which is slightly bigger and more grey-phase dominant) could that be a factor


"Tipping point," also called an Allee effect, is when the system (in this case roofed grouse numbers) is drawn so far from their normal equilibrium that they cannot recover and drift towards a new equilibrium which can be a smaller or greater number or none at all. Definitely UNlikely in this case unless numbers get VERY low.

Northern MN has always been full of predators, but roofed grouse numbers have always been more reflective of things like winter/spring weather, ice storms, and so on. Whether West Nile is up there, I don't know. It certainly seems likely. It appears to be almost everywhere at some level now.

Armchair declarations of what is wrong with any wildlife population is likely to be wrong more often than not. Not that such a detail like that could ever affect the internet from pontificating.

Someday soonish I need to get back up there and chase them again, before I'm dogless or kneeless.


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BrentD, (Professor - just for Stan)
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