A Bottomland Forest in May

     For a few hours today, May 17, 2017, I sat under sun-bathed deciduous leaves in a bottomland forest along a creek in northern Lancaster County, Pennsylvania.  Bird songs and the sweet smell of damp woods permeated the cooling breezes this warm morning.
     Several kinds of plants were in lovely full bloom today along the gravel road I was on.  Golden ragworts with their yellow blooms, wild geraniums that have pale pinkish-purple blooms and daisy fleabane with their small, soft-petaled, light-pink flowers dominated the blossoms along that woodland road.  Wild gingers, Dame's rockets, and May apples with their umbrella leaves, were also in bloom along that woodland road.  And I saw the abundant leaves of skunk cabbage and colt's-foot plants that are already done blooming on the forest floor for this year.
     I also saw several beautiful tiger swallowtail butterflies fluttering through the woods and over the road and creek.  Each swallowtail spent the winter dormant in its chrysalis under leaves on the dead-leaf carpeted forest floor.  But the warmth of April's and early May's sun allowed the swallowtail pupae to finish developing into butterflies and emerge from their cocoons as the first generation of their kind of the year.  
     Although those bottomland woods are dominated by tall white oak, red maple and tulip poplar trees, spicebushes are abundant in the understories of the woods, and there are many thickets of multiflora rose and other kinds of shrubbery in sunny clearings, all of which, including the creek, help diversify the forest and the species of small birds that nest in them.  During the few hours I was still and quiet in that woodland, I saw birds chasing others of their kind out of their territories, feeding, singing, bathing, copulating and gathering nest materials.  Most of them are camouflaged in the woods and, sometimes, hard to see.
     I saw some permanent resident birds in those woods, including blue jays, northern cardinals, Carolina chickadees and other kinds.  But my main interest was the migrants that come to woods like this one to raise offspring through summer.  
     Gray catbirds dominate thickets in the woods where they pick up invertebrates to eat.  And some of them spend a little time getting invertebrate food from the mud flats of the creek.  I heard some of the males singing gently from the depths of the thickets.
     Veeries, which are a kind of thrush, dominate the bottomland woods, which is their favored summer habitat.  No other kinds of thrushes are as well adapted to woodlands along streams and creeks as are veeries.  They are brown on top which camouflages them on the forest floor, where they nest and eat invertebrates, and off-white below with faint speckling.  Veeries bounce across the woodland floor as they run and stop, run and stop like their relatives the American robins do across lawns when looking for invertebrate food.  Veeries' unique, flute-like songs spiral down, down and are most often vocalized at dawn and dusk.  
     Wood thrushes nest on sapling trees in the understories of deciduous woodlands, but not necessarily along waterways in the woods.  Male woodies also sing flute-like songs that sound like "ee-o-laay" or "a-o-lee". 
     Louisiana waterthrushes are a kind of warbler that hunts invertebrate food in the shallows of running water in woodlands, including this creek in northern Lancaster County, and raises young in crevices in stream banks along those woodland waterways.  Waterthrushes constantly dip and bob their bodies and tails as they walk along the creek in search of food, which, I think, is a form of blending into their streamside habitat.  Waterthrushes dance along the water's edges with the same rhythm as debris bouncing in the shoreline current.  Therefore the waterthrushes look like that debris to predators.
     I saw and/or heard other species of neotropical, migrant birds, besides the thrushes and waterthrushes, today in those same woods.  They included a couple each of red-eyed vireos and eastern wood pewees that I heard in the woods, and two pairs of Baltimore orioles, a female scarlet tanager gathering nesting material, a male redstart singing, and two female rose-breasted grosbeaks that apparently were feeding on invertebrates when I saw them. 
     The dark and orange male orioles and redstart were colorful and striking to see flitting around the green, sun-drenched woods.  And as I watched them, I thought of the different woodland layers these neotropical, nesting birds use each summer, though there is some overlap of woodland strata.  Waterthrushes raise young in the lowest strata, at the stream level.  Veeries hatch offspring in nurseries on forest floors near woodland waterways.  Wood thrushes, redstarts, red-eyed vireos, rose-breasted grosbeaks and catbirds rear youngsters on sapling trees and shrubbery in the understory level.  Baltimore orioles build swinging cradles half way up trees along creeks and streams in bottomlands.  Pewees raise young half way up trees up slopes and scarlet tanagers hatch babies in treetop cradlesn on those same wooded rises.  These birds raising young at different levels in the woods reduces competition for nesting space and food among those species.  That allows many birds of different kinds living space in the woods.
     Today was a good day in local woods, with the beauties of flowers, butterflies and neotropical, nesting birds.  Those bird species will continue to live and nest in those woodlands until the end of summer when they will migrate to the West Indies, Mexico, Central America and northern South America, depending on the species.