Something I remember from my youth might be a solution. People were paid a small bounty for killing certain species; just about enough money to pay for their ammunition. The species I remember my cousins hunting for bounty was the magpie, which at the time Colorado found objectionable.
Geese, of course, are edible, even prized food in some cultures. Trap or shoot the geese and give the meat to homeless shelters, jails and prisons, and the like. Vultures and cormorants are likely to be inedible by humans, but might be usable in pet or stock food.
Today I see many more red tailed and other hawks than I did some decades ago. They don't seem to be a problem so far, mostly they keep down the rodent population. I wonder why there are more large birds now than formerly? The "Silent Spring" DDT theory has been debunked. The American Council on Science and Health reports:
A 1978 National Cancer Institute report concluded—after two years of testing on several different strains of cancer-prone mice and rats—that DDT was not carcinogenic. As for the DDT-caused eggshell thinning, it is unclear whether it did, in fact, occur and, if it did, whether the thinning was caused by DDT, by mercury, by PCBs, or by the effects of human encroachment. And as recently as 1998 researchers reported that thrush eggshells in Great Britain had been thinning at a steady rate 47 years before DDT hit the market; the researchers placed the blame on the early consequences of industrialization.Maybe big birds are getting used to having us around, adapting to human-influenced environments? Stranger things have happened.
