BIRD NESTS THERE IS A FLURRY OF AMBITIOUS ARCHITEC-
as birds scurry to meet construction deadlines. Like their human counterparts, spring is the season when the bustle is at its height. However, the commencement of construction seldom begins when the calendar indicates it is spring. Rather, it varies with environmental factors such as rainfall, temperature, water levels and amount of snowfall, as well as elevation from sea level to mountaintop and from north to south. Nesting activity may even differ within the same species in the same geographic location. Birds use nests to protect themselves and their unborn and developing young from danger and inclement weather. To guard against predators, tors, birds are ingenious and inventive in building inaccessible, armored, camouflaged or colonial nests, which provide safety in numbers. The majority of birds return to the same nest-ing area. With the excepption of some of the larger er birds of prey, most species es build a new home each ach year. Several avians, such uch as the red-winged blackbird, ird, fashion a fresh bassinet for each brood as well. f d Nesting sites and feeding places usually coincide. For example, many warblers incubate eggs and forage within the upper branches of tall trees. Kingfishers, who frequent streams, ponds and shorelines, tunnel into soft banks TURAL ACTIVITY IN THE AIR
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creating a dwelling close to the minnows and crayfish they devour. Ground-feeding sparrows nest on or near the ground in immediate proximity to the insects and seeds they consume. Woodpeckers chisel out homes in trees and grab grubs and bugs from them as well. Since building a nest requires tremendous time and energy, birds maximize the use of locally-available materials. Sticks and stones, mud and moss, leaves and lichens, webs and weeds are among the choices of construction materials in the bird world. Nests in open habitats are made of grass; in marshlands of reeds; and in shrubs and trees, of twigs and branches. To furt h e r decrease visibility, some species camou camouflage the outside of their nests by adding lichens as in c the case of hummingbirds and moss in the case of kinglets. mosses As a result, these master builders and architects produce an eco ecologist’s dream of blending, nat natural abodes. R Roughly 78 North America birds rely either partially can o wholly on tree cavities for or n nesting sites. A myth exists a about woodpeckers killing trees by their drilling or chipping, but these trees even though they may no look so, are in a state of not alread dead (commonly called decline or already ) Chickadees, Chi k d h snags). nuthatches and woodpeckers excavate their own holes, but most other cavity-nester songbirds choose sites chiseled by previous tenants or pick natural cavities. Bluebirds, wrens, chickadees and tree swallows are a Photos provided by Andrea Lee Lambrecht