"EASTERN ROADRUNNERS"

      Brown thrashers are "eastern roadrunners".  These thrashers mostly feed on invertebrates, seeds and berries on the ground, and usually run rapidly from danger, rather than fly.  But one summer afternoon, I was watching a handsome brown thrasher flipping leaves and scratching about for seeds and invertebrates in the soil of a lawn just outside a woodland.  He had warm-brown feathering on top, as all brown thrashers do, which camouflages them on the ground.  

     Suddenly a red-shouldered hawk swooped down toward that thrasher with the intent to kill it for a meal.  I thought the thrasher was doomed.  But the intended victim flew up toward, but under, the hawk and winged low across the lawn to the woods where it disappeared.  The hawk overshot the thrasher and by the time that predator swung around, its intended prey was long gone.  I thought, "clever thrasher".

     At other times, over the years, however, I 've seen a few brown thrashers darting quickly, on foot, under shrubbery, rather than flying, to escape potential predators.  And I must say they are fast on their long, strong legs, like tiny, feathered racehorses. 

     Many of us know about Wile E. Coyote and the roadrunner; the bird who always outsmarts that wild canine in western American deserts.  Well, there are real coyotes and real roadrunners in those dry habitats.  And roadrunners do run really fast.  Because brown thrashers appear to be evolving along the same lines as the unrelated roadrunners, some people call them "eastern roadrunners".  

     Brown thrashers and roadrunners are an example of convergent evolution; coming from different backgrounds, but becoming much alike because of their similar habitats and ways of life.  Thrashers come from the mimidae family of birds, while roadrunners stem from New World cuckoos.  But the thrashers' and roadrunners' running rapidly instead of flying is something they have in common; convergent evolution.     

     Brown thrashers are robin-sized birds that are built for feeding on the ground and escaping predators.  They are camouflaged on the ground and have long, strong legs for rapid running to escape danger.  They have large, decurved bills they use to flip over dead leaves on the ground to spot invertebrates, and they sweep those beaks from side to side among dead and fallen leaves to stir up invertebrates and other edibles.  And they have long tails they use for balancing and steering when running or flying.   

     Brown thrashers are the only thrashers that raise young in the eastern United States.  It's estimated that about six point two million pairs of brown thrashers rear offspring here.  Each pair builds a cradle of twigs, rootlets and dry grass in shrubbery, young trees or on the ground in dense, tangled thickets of vines and numerous bushes in sheltering hedgerows, woodland edges and older suburbs with many planted shrubs.  Each female thrasher lays four or five eggs in her nursery and both parents feed the young invertebrates.  

     Brown thrashers are attractive, interesting birds of dense thickets.  And they are becoming roadrunner-like.  They are well-worth knowing.                          

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