On Sat, 7 Aug 1999 MBlanchrd at aol.com wrote:

> This is only my opinion, mind you, but..........I have a theory that the
> introduction of the rock dove (brought over by the Pilgrims as a food
> source) was the beginning of the end for the passenger pigeon. Yes, I know
> that humans shot them in the hundreds of thousands.......but I believe that
> the rock dove brought diseases with it that our passenger pigeon had no
> defenses against. Just like the Indians were decimated by smallpox and other
> diseases, the rock dove's diseases probably put the passenger pigeon on that
> slippery slope to extinction. I've never seen anything in any scientific
> literature to back this up. It's just a hunch.

The two species occupied very different niches and thus were not in
competition. The best current understanding of why passenger pigeons went
extinct is that they were hunted to a point where their population dropped
below that required to breed.

Dale Goble
Moscow