Arctic Raptors Come South

     In December of 2013, my wife and I rode through snow-covered, Lancaster County farmland around our home in New Holland to spot snowy owls that had been reported in our area.  We found three that afternoon, two of them within a hundred yards of each other.  Those two were perched on the snow in cold wind and one was eating a dead snow geese that it either killed itself or was scavenging.  What a wild scene in civilized Lancaster County; two snowy owls on snow and one owl eating an Arctic tundra-born goose.  The owl stood on the goose, as if protecting its meal from other scavengers, as it tore off chunks of meat and swallowed them whole.  No species of bird has teeth. 
     We here in southeastern Pennsylvania are occasionally treated to sightings of Arctic tundra raptors, including rough-legged hawks, snowy owls and gyrfalcons, in that order of sighting frequencies, during some winters.  These birds of prey nest on the tundra, but drift south during certain winters in their searches for prey.  Only the rough-legs do so annually.  And when wintering in this part of Pennsylvania, as elsewhere, all these raptors reside in the vast open spaces of this area's cropland, which, to them, is reminescent of the tundra where they hatched.  And to us human residents here, they are representatives of the Far North, Inuits and polar bears. 
     Rough-legged hawks nest on cliffs in the Arctic.  They prey mostly on lemmings, which are much like field mice.  But in late autumn they drift south to open spaces in Canada and the northern United States.  Here in southeastern Pennsylvania they either perch in lone trees in large fields or hover into the wind on beating wings to watch for mice and small birds, including the abundant horned larks.
    Rough-legs are beautiful hawks with dark bodies, tawny heads and white bases to their tails.  Some individuals are almost black all over.  They can easily be distinguished from their larger, stronger cousins, the red-tailed hawks.
     Rough-legs used to be common in southeastern Pennsylvania in winter, until red-tails became more abundant, particularly in winter.  I think rough-legs lost the competition with their more aggressive cousins for feeding territories here in winter and so now are fairly scarce.  But now it is more of a treat to see one or more of these arctic hawks in our winter croplands.
     The magnificent snowy owls winter this far south only every four or five years, and then only one or a few are present.  But they were quite common here in southeastern Pennsylvania during the winter of 2013-14.  In Lancaster County alone, we saw several snowies perched on snow and fences in the larger fields. 
     Snowy owls are also dependent on lemmings for food, but will catch and eat any other creature they can easily handle.  As lemming populations build, so do snowy owl numbers because when male owls court their mates they bring her lemming gifts to eat.  The more of those rodents he brings, the more eggs she lays, up to eight, in her cradle on the ground.  And there are plenty of lemmings to feed all those owlets. 
     But if lemmings are not numerous, the males ingest all they snare, give no gifts to their mates and those female snowies lay no eggs at all that year.  That practice is a built-in birth control.  And it's after a lemming numbers crash that many snowy owls, particularly younger birds, drift south for the winter in hopes of finding enough critters to survive until spring when they go north again.  But many migrant snowies, especially the young, don't survive to make the trip north.   
     Snowy owls are mostly white with many dark speckles on younger birds and females.  Adult males have very little speckling on their white plumage.  That feathering, of course, camouflages the owls on snow.
     Wintering gyrfalcons are rarely as far south as southeastern Pennsylvania, but we get one or two here some winters.  But a couple winters in a row in the early 1980's saw at least three stately gyrs in Lancaster County alone.  Two of them spent nights on the rocky cliffs of a quarry.  Watching them come in to the quarry for the night was exciting and inspiring.  Sometimes we would see one or both approaching the quarry in a low, fast glide over the fields, sweep into the quarry, swing around inside the cliffs and finally land on a rock ledge.  They did all that with scarcely a wing beat!  
     During each winter day, the gyrs hunted rock pigeons and other, larger birds in extensive cropland.  Often they perched on top of lone trees in fields to watch for prey.  Then they ambushed their intended victims with lightning speed.  Those habits are reminders of their life on the tundra.  They raise young on cliffs and hunt birds across the treeless tundra.
     Gyrs are either white with dark markings or smoky gray all over, with darker spotting.  Both colors of feathering camouflages them in their habitats. 
     Gyrs are the largest of falcons, being larger than crows.  And they are swift, powerful flyers, forcing prey birds to the ground where they kill and eat them.        
     Look for these Arctic raptors in wide, open spaces this winter, or succeeding ones.  They are exciting and inspiring to experience.  And they are a bit of tundra come south.