Twilight Woodland Songs

     Enchanted deciduous woodlands in southeastern Pennsylvania are made more so at dusk in May and June by the lovely songs of the males of four kinds of birds, including wood thrushes, veeries, eastern wood pewees and gray catbirds.  Those male birds sing beautifully from the shadows of trees and shrubs as twilight gradually deepens to full darkness.
     All those bird species blend into the summer woods where they raise young, making them hard to spot.  But their pretty, heart-tugging songs make up for their lack of being visible.  However, when seen, they are charming in appearance and look like they belong where they are.  As everywhere, each species is a product of the habitat it adapted to.  It fits right into the environment that shaped it to be what it is.  
     All these bird species winter farther south.  Wood thrushes and veeries winter mostly in Central America.  Pewees also spend winters in Central America, and northern South America.  And catbirds spend that harshest of seasons in the southern United States.  Migration happens not to avoid cold, but to find reliable sources of food in the warm south when the north is frozen with ice and snow.  And since these birds mostly consume invertebrates that are dormant and inaccessible in winter, they must go farther south to find food.
     Wood thrushes and veeries are both species of thrushes that nest in southeastern Pennsylvania woods, as they do through much of eastern North America's forests.  Always handsome when seen perched low in the woods, both kinds are brown on top, which camouflages them on carpets of dead, fallen leaves on forest floors.  And they are white below with rows of spots.  The dots on veeries are much fainter than those on wood thrushes. 
     Related to the familiar American robins of suburban lawns and fields, wood thrushes and veeries are shaped like robins, but smaller.  And those two kinds of thrushes run and stop, run and stop across dead-leaf, moss and fern-strewn forest floors to look for invertebrate food, as robins run and stop on lawns and fields. 
     Wood thrushes raise young in twig and leaf nurseries placed low in understory shrubs and sapling trees.  Veeries rear offspring in leafy cradles on woodland floors near streams.  Those different nesting niches reduce competition between wood thrushes and veeries for nesting space and food.
     Wood thrushes and veeries are elegant when perched low in the woods.  And their lovely, flute-like songs are ethereal.  Wood thrushes utter flute-like phrases that sound like "e-o-laaay" or "a-o-leeee".  Each of the Veeries' songs seem to breezily spiral downward, downward, downward.
Veery songs seem out of this world!
     Eastern wood pewees, which are a kind of woodland flycatcher, often join thrush concerts in the woods at dusk.  Pewees sing sweet, gentle songs at twilight that seem to say "pee-a-weee", "pee-a-weee", "pee-uurrrrr".  Those seemingly sad phrases continue and continue and finally fade into the darkness of most every dusk during May, June and into early July, the breeding season of all these bird species. 
     Pewees are gray all over, which allows them to blend into the color of tree bark.  Each female makes cradles of tiny twigs, grass, lichens and spider webs in forks of twigs high in the trees.   
     Gray catbirds are also gray with darker caps.  Their plumage allows them to blend into the shadows in the depths of dense shrubbery on woodland edges where they summer and nest.  Their lovely, twilight songs are soft and quiet, as if each male songster sings to himself.
     The beautiful, melancholy songs of these four kinds of summering birds make the already lovely deciduous woods of northeastern North America more enchanting at twilight from early May to mid-July.  These are bird songs well worth hearing as dusk deepens to full darkness.