Arctic Birds in Ice Age Georgia

J.J. Audubon reported 2 species of birds with arctic affinities as rare stragglers in Georgia during the 19th century.  He wrote that snowy owls (Bubo scandacius) occurred as far south as Georgia, and he even witnessed Atlantic puffins (Mormon arcticus) in Savannah Harbor during the harsh winter of 1831/1832.  The northern hemisphere experienced a minor cooling period known as the Little Ice Age between 1300 AD-1850 AD, so perhaps it’s not surprising that some species of arctic birds spread south when particularly hard winters occurred.  Though the Little Ice Age had a major impact on human agriculture, it was a minor blip compared to the Ice Ages of the Pleistocene when glaciers encompassed all of what today is Canada.  Arctic birds that were rare stragglers during harsh winters of the Little Ice Age were probably common during full blown Ice Age winters.

A map of the extent of the glaciers that covered North America during the Ice Age.  This depicts the Last Glacial Maximum.  During much of the Ice Age, the glaciers weren’t this large, but were still much more expanded than they are  today.  The range of many species of birds, especially ducks and geese which today summer in places that were miles under glaciers then, must have been pushed farther south.  This is a neat map that also shows loess formation.

Snowy owl about to catch a small rodent.

Snowy owls prefer open tundra habitats and nest on the ground.  During the Ice Age, tundra habitat was displaced much farther south than it is today.  Winter appearances of snowy owls in the southeast were probably common.  During the cold spell of the early 19th century they expanded their winter range south along the coastline because the open landscape of coastal dunes resembled their preferred habitat of tundra.  Grasslands expanded during Ice Age stadials, so snowy owls would’ve headed south to inland areas as well as the coast then. 

I’m not aware of any snowy owl sightings in Georgia since 1900.  There was a sighting in Springhill, Tennessee in 2009, but that was the first in that state since 1989.  They still invade Wisconsin and Ohio on a consistent basis.  The following youtube video shows a snowy owl in Toledo, Ohio.

http://www.youtube.com/watch?feature=player_detailpage&v=S4fWoUxH3h8

It may not be harsh winters that cause snowy owls to extend their range south.  Some scientists think their population increases following lemming population explosions, and this explains why they may be more commonly seen during some winters.  Lemmings and mice are their primary food, though these large owls will prey on rabbits, squirrels, ptarmigans, grouse, and other owls.  J.J. Audubon observed them fishing.  He writes that the owls lay flat next to streams and snatch fish with their talons.  Others report them taking fish by diving from the wing like ospreys.  They are also a danger to cats and small house dogs.  A snowy owl killed a small house dog on a Wisconsin suburbanites back porch recently.

Atlantic puffins.

I’m unaware of any puffin sightings in Georgia since 1900.  But during the Ice Age, enormous colonies of these birds nested on rocky coastlines much farther south than they do today.  The ocean receded then, exposing many isolated islands where they could nest unmolested by predators.  Puffins probably often occurred off Georgia’s coast during Pleistocene winters.  This species nests in burrows and feeds upon small fish which it captures by swimming underwater.  The burrows of a colony are linked together underground like a maze. 

No fossil evidence of these 2 species has been found in the south, but I’m certain they would have made a birdwatcher’s checklist during Ice Age winters.

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3 Responses to “Arctic Birds in Ice Age Georgia”

  1. jamesrobertsmith Says:

    They’re trying to reestablish puffins in Maine. I haven’t checked on the status of them in that state in some time, but I recall they were actively working toward that as far back as the 1980s.

  2. markgelbart Says:

    I didn’t even know they’d been extirpated in Maine.

  3. jamesrobertsmith Says:

    Yep. Wiped out. Not sure what the status is just now but they were trying to reestablish them as far back as the 1980s.

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