Though we are often overwhelmed by the hordes of geese, swans, gulls, blackbirds and robins that come into Lancaster County, Pennsylvania in March, there are some other, more subtle, migrants here at that time as well, including mourning doves, wood ducks, killdeer plovers, eastern bluebirds, tree swallows, American kestrels, eastern phoebes and Louisiana waterthrushes. These birds all come into this county during March, as elsewhere in northeastern North America, to raise young. A few doves, killdeer, bluebirds and kestrels are in Lancaster County through winter, but their numbers become increased in places where they didn't exist all winter by incoming migrants of each species. All these subtle migrants are adapted to human-made lawns, fields, impoundments and buildings, depending upon the species, for at least part of their life cycles, which increases their numbers and adds to our enjoyment of local wildlife. And all these kinds of incoming birds help make March an interesting month in this area.
Mourning doves are one of the first species to come back to Lancaster County, as elsewhere, to nest, mostly in coniferous trees on lawns. We hear the males' cooing and see their courtship flights of deep wing flapping, then soaring in a circle while banking one way and then the other. Each pair of doves produces two young a month, every month from April to September. They do that by staggering their broods of two young each. When the first brood of young are half-grown, the female lays two eggs in another nest that hatch when the first chicks fledge and are on their own. One mate of each dove pair sets on the younger eggs while the other mate feeds the young a mixture of mucus from their throats and pre-digested weed seeds and grain from nearby fields. Twice a day the adults switch roles in caring for their young.
Wood duck females hatch clutches of about 12 ducklings in a tree hollow near a waterway or built impoundment, or boxes erected especially for them. Woodies raise young these days in their traditional woodland habitats or in riparian woods along waterways in farmland. Hen woodies take their youngsters to water to feed on aquatic invertebrates that are packed with protein for growth.
Killdeer plovers are a kind of inland shorebird. Most shorebirds are adapted to open habitats of short grass, mud, or sand along shores. Killdeer prefer living and nesting in short-grass pastures, recently plowed fields of bare soil, or gravel driveways, parking lots, railroad beds and flat roofs. They and horned larks are the only two kinds of local birds that do that.
Killdeer lay their four eggs (all shorebirds lay four eggs) on the bare soil of fields or on gravel. The young hatch fuzzy, open-eyed, and ready to run and feed themselves, all of which are good traits to have when hatching on the ground. Young and adult killdeer eat invertebrates.
Eastern bluebirds probably are more common today than ever in their history. They have adapted to hedgerows, overgrown fields and meadows, and bird boxes erected especially for them. All those habitats were created by people. The beautiful bluebirds feed on a variety of invertebrates.
Tree swallows, like bluebirds, nest in tree cavities and bird houses, but in open areas near bodies of water, including human-made lakes and ponds. The first of the swallow species to arrive here, always sometime in March, pairs of them quickly look for nesting hollows. Sometimes a group of tree swallows will gang up on a pair of bluebirds to take over the latter's nesting site. The bluebirds try to keep their nesting place, but usually lose to the persistent, aggressive swallow gang.
American kestrels, which are a kind of falcon related to peregrines, also rear offspring in tree cavities, in open cropland. These little hawks prey on mice, small birds and grasshoppers, for the most part. They are valuable to farmers by keeping the numbers of mice and insects down.
Eastern phoebes are a kind of flycatcher that arrives here in March and feeds on flying insects in the warmer mini-climates of sheltering woodlands where insects can become active. Males sing a simple, repetitive song that sounds like "Phoebe".
Phoebes traditionally nest on rock ledges under overhanging boulders near water in woods. But they have adapted to building cradles of mud and moss on building and bridge supports in the woods and thin, riparian woodlands along waterways as well.
Louisiana waterthrushes, a kind of warbler that winters in Central and South America, arrive along woodland streams here late in March. Males of this species have loud songs so they can be heard above the music of the tumbling streams. Waterthrushes dance along the edges of the waterways to search for invertebrates under the pebbles. The dance is a type camouflage, which mimics the bouncing of bits of bark and other debris in the current along the edges of the water.
Waterthrushes build dead-leaf cradles in a niche in a stream bank behind the projecting roots of trees. There the camouflaged young are relatively safe from predation.
These are some of the more interesting birds that arrive here in March to raise young. Though their migrations into this area are not spectacular like those of snow geese and blackbirds, these pretty birds are well worth watching for in that first month of spring.
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