White wings originally were from areas in south Texas or farther south. They only started showing up here 20 years ago when we had global warming.
Ya I'm recalling "Outdoor Life" from the seventies, where to a teenager in New York stories of shooting white-wings on the Border were as alien as if it took place on the moon.
On a different species... Coopers Hawks are the original "chicken hawk", a species intensively persecuted to the extent it became "a rare forest hawk" over most of the Lower 48.
Pretty much every tree in San Antonio has white-wings nesting in it now, the population in the city alone estimated at more than
two million. Since I've been in Texas, Coopers Hawks have always been present in the Hill Country just north and west of town, they even nest in the wild setting of Camp Bullis, technically within the city limits.
Never did make the leap to nest in the city though, despite the enormous prey base in the form of white-wings now available.
Starting about ten years ago, Coopers were noted as nesting in several Florida cities, as noted ruefully by those who keep colonies of purple martins. Several martin colonies have been wiped out entirely by these hawks.
These urban Coopers have been spreading east, first across Louisiana, and a few years back in the Houston area. Ain't reached San Antonio yet, but when they do they should prosper.
The point being that the Western Coopers in the Hill Country, tho' outwardly identical, obviously differ in behavior from these new urban ones, most likely due to genetics.
Same thing appears to be true of White-wings, it likely weren't climate that kept 'em out, more'n likely the birds themselves. Nowadays they have gone urban, big time, flying considerable distances out of these centers to surrounding rural areas to feed.
Birdwatcher
