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Posted by Alex Harper on 11:05:09 10/23/14
In Reply to: Re: Need help finding Smooth-billed Ani posted by kurt d.
Kurt,
Freezes, pesticides/insecticides, car strikes (at least for the urban populations; young anis near Ft. Lauderdale Intl. Airport were observed dead on the road at least once), habitat loss and genetic bottlenecking are much more likely than the colonization the Cooper's Hawk.
Anis were relatively new to the avifauna scene of Florida, probably only colonizing the state when the going was good in the mid 20th century.
On the ani in "Florida Bird Species" by Robertson, Jr. and Wolfenden (1992) mention "By 1970's, widespread and locally common in the southern two-thirds of Florida, and rare, irregular elsewhere in the state. From 1977 through the 1980s, numbers and range were sharply reduced by severe freezes (also by reduction of vacant-lot habitat in developing areas...)"
There is one more layer to the demise of the ani in South Florida: they have a complicated social structure and are communal nesters. As with many species with such a breeding strategy, the health and success of one family of anis depends on the health and success of neighboring ani families to exchange individuals. Species like this can be rather successful but are fragile when under pressure and the health and distance between neighboring family groups thin out.
The first confirmed nesting Cooper's Hawks in Miami-Dade County were found around 2003. By then, anis had already been in dire straits, with a few small populations here and there.
Politely, I think you are too quick to point the finger at the Cooper's Hawk.
Alex Harper
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