Pleistocene Eagles

After I finished formatting Georgia Before People I happened to review the list of fossil birds recovered from the La brea tar pits in Los Angeles and realized I had omitted mentioning a spectacular species of extinct eagle that probably occurred in Georgia as well.  I was too lazy to go back and add a discussion of this eagle into my subsection about Pleistocene birds.  (Take my word for it–formatting a book line-by-line is a pain.)  So here I’ll mention it to make up for my omission.

Woodward’s eagle (Amplibuteo woodwardi) was North America’s version of the harpy eagle which today lives in the jungles of South America and preys on monkeys and tree sloths .   Unlike its modern relative, Woodward’s eagle likely was well adapted to hunting the open Pleistocene landscapes rather than closed canopy jungles.  Evidentally, it couldn’t survive the ecological changes that occurred at the end of the epoch.  Its extinction may have been related to the extinction of the megafauna which probably provided a great deal of food as carrion when the large beasts died, though I’m sure this species of eagle was an active hunter as well. 

In addition to the fossil remains found in California, Woodward’s eagle specimens have also turned up in Florida and Cuba, so it’s safe to assume they probably lived in Georgia.

I did mention the hawk-eagle (Spizaetus grinnelli) in my book but didn’t realize at the time that it had another common name–Grinnell’s crested eagle.  It has also left specimens in California and Florida, meaning it likely lived in Georgia.  California and Florida have outstanding fossil sites that are very comprehensive compared to those in Georgia for a number of reasons.  California has the tar pits; Florida has lime sink lakes and caves where the basal chemistry preserves bones.  Normally, bird bones are particularly rare compared to mammal bones because they get crushed into powder when buried under sediment.

Florida’s fossil record also has evidence of the long-legged eagle (Westmoregyps daggetti) which occupied an ecological niche similar to the African secretary bird.  What a neat bird this was–an eagle with long legs that hunted on the ground like a road runner rather than dive bombing from the air like all of its modern relatives.  The Florida specimens, however, date to early in the Pleistocene, and it’s unknow whether they still survived in the southeast late in the Pleistocene.

Oh what a wonderful wilderness that used to be.

Next up: photos of an Appalachian balds–relic landscapes of the Pleistocene.

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