Scavenging Eagles

     On the morning of November 20, 2014, I was driving through farmland in Lancaster County, Pennsylvania when I saw what I thought was a hawk perched upright on a bare tree about a quarter of a mile away.  Through binoculars I noted the bird was an immature bald eagle.  And I saw a few other bald eagles near that first one.  I quickly thought of a way I could get closer to those birds for better looks, but still stay in my car so I wouldn't scare the eagles away.
     Arriving at the spot where the eagles were perched in a line of several trees, I saw hundreds of wintering American crows down from their breeding territories in Canadian forests in those same trees, in the air and on the ground, many of them cawing raucously at once.  A few turkey vultures were on the ground and other turkey vultures and a few black vultures were in the air gracefully soaring toward the ones on the ground.  I noticed, too, that several red-tailed hawks were in the same trees the eagles were perching on.  I counted 12 red-tails and 30 bald eagles in those trees.  About half those eagles were immature with brown plumages all over.  But all the eagles were magnificent and exciting to see, especially in Lancaster County cropland.  And all these birds together created an enjoyable show. 
     In the process of watching the hawks and eagles, I noticed that some of both kinds had risen from the ground or landed on it out of sight on the other side of a small rise.  I had the idea that 12 and 30 were conservative numbers. 
     The draw for this post-breeding, wintering gathering of crows, vultures, red-tails and eagles was a nearby poultry farm where thousands of domestic birds are raised for meat.  But some die of disease or trampling and are disposed of in fields.  There they are an abundant food for a variety of birds and scavenging mammals, such as foxes and raccoons.            
     There are bigger concentrations of wintering bald eagles in North America than this one, including several in Alaska, along the Mississippi River and lower Susquehanna River, for example.  But this is the biggest inland gathering of balds I had ever seen or heard about, which is their greatest excitement in this county.
     Bald eagles have increased their numbers greatly through much of North America because of the ban on using DDT in fields, their being protected by law, and their adapting to human-made habitats that are less than ideal.  Scavenging dead farm animals is one of those adaptations the eagles and other kinds of larger birds have advanced for their survival.
     Most people think of bald eagles as birds of large bodies of water where they catch and scavenge fish, ducks and other creatures.  And many of them do.  But many eagles today regularly get food inland, particularly on fields.  Those pioneering eagles, in time, may create a new species, one dependent on inland creatures.
     Nature is always beautiful and interesting, no matter where it is found.  And critters that adapt to human-made habitats and activities are the most intriguing of all.