Some Opportunistic Wildlife

     Toward the end of June of this year, I was watching the two young bald eagles in their large, stick nest near Washington D. C. via our computer.  I saw a dragonfly repeatedly perch on a twig in the bald eagle nursery, zip over that cradle in a tulip tree and return to its twig.  I think that dragonfly was attempting to catch, with some success I'm sure, flies that were attracted to meat scraps in the eagle nursery.  While watching the young eagles and the dragonfly, I thought about the other creatures I saw over the years taking advantage of situations that benefited them, and were interesting to me.
     While watching great horned owl, red-tailed hawk, bald eagle and osprey young, and their parents, in their bulky nests, by computer, I see several flies buzzing around in those raptor nurseries because of the meat and fish bits and dead critters lying in those cradles until the scraps are eaten.  Those flies are there to lay eggs on the dead meat and fish.  Maggots hatch from those fly eggs, with the intent of consuming the meat and fish left over from feeding young owls, hawks, eagles and ospreys.  But some of the adult flies are eaten by spiders and small birds that are attracted to raptor cradles.  Those arachnids and small birds are not bothered by the raptors because they are too small to be of any interest to those large birds of prey.
     Also when watching raptor nests, it's amusing to see house sparrows and/or starlings fly in and out of crevices between sticks in the cradle structures.  These two kinds of little birds, originally from Europe, have young tucked in those openings and are regularly in and out of them to feed their babies.  That may seem like risky business, but, again, these birds are too small to prey on.
     I remember several years ago seeing an adult green frog sitting on the muddy shore of a sluggish stream and closely facing a dead fish.  Curious as to what that frog was doing, I looked at it with binoculars.  The frog was using its long, sticky tongue, that is attached to the front of its mouth, to snare flies off the dead fish and flip them into the back of its mouth for swallowing.  That frog found a bonanza of flies and was taking full advantage of it until it was stuffed with those insects.
     Over the years, people have asked me why bats sometimes swoop close to peoples' heads during summer evenings.  I don't know why they do, but I have theory that makes sense to me.  People wearing perfume, deodorant or hair spray smell sweet, like flowers.  Insects might mistake those artificially sweet scents for blossoms and are drawn to those smells to sip sweet-smelling nectar.  And through their echolocation, the bats sense the flying insects around the peoples' heads and swoop down for a meal of insects that they grab in their toothy mouths.  The bats are merely taking advantage of a bounty of food; they are not interested in the people.
     Laughing gulls, those abundant, black-headed gulls that utter raucous "laughter" along the Atlantic seacoast in summer, take advantage of many human-made food sources.  Having evolved to scavenging edibles along ocean beaches and in salt marshes, they are also adapted to eating peanuts, popcorn and other "human" foods that folks leave lying about on beaches and boardwalks, or feed to laughing gulls for the peoples' entertainment.  The adaptable, omnipresent laughing gulls take full advantage of any food source, natural or human-made.
     Chimney swifts, eastern phoebes, rough-winged swallows and killdeer plovers hatch young in human-made niches, which has increased the populations of each of these small birds. 
      Swifts migrate into eastern North America to hatch young on twig platforms down the inside of chimneys, as they had down the inside of hollow trees.  Swifts use their saliva to glue the twigs to the sheer walls of chimneys and feed flying insects to their young.
     Phoebes build mud and moss nurseries on rock ledges, under overhanging boulders, near water in woods.  And they also raise offspring on supporting beams (rock ledges), under porches and small bridges (overhanging boulders) near water in woods.  They also feed flying insects to their chicks.
     Rough-wings rear babies in abandoned kingfisher holes in stream burrows, or in holes they dig themselves.  But they also hatch youngsters in drainage pipes that extend over waterways and impoundments.  They, too, feed flying insects to their progeny. 
     And killdeer hatch young on gravelly shores of inland waterways and impoundments; and on gravel driveways, parking lots, railroad beds and flat roofs.  They and their precocious young eat a variety of invertebrates.   
     These are examples of wildlife in the Middle Atlantic States taking advantage of human-made niches to the creatures' benefit.  There are many, many other examples the world over.