Spring winging: The annual spring songbird migration
by Pam Owen, Spring 2006
For those of us who like to watch birds—and there are lots of us in Rappahannock, winter bird watching can get a bit monotonous. The birds that overwinter have changed out of the brightly colored feathers in vogue during mating season, and most of the truly colorful birds have gone south to warmer climes. Seeing a male cardinal in his bright red feathers and the occasional bluebird is about all
we can hope for in those dreary winter months.
But then spring comes—and a parade of brightly colored songbirds wing their way through the county on their annual migration north. Some even stay to mate and raise their young here. Not wanting to be upstaged and ready to mate themselves, some of the local birds also put on their best plumage in the spring. Male goldfinches, for example, turn from olive drab to bright yellow and black.
There are four broad flyway belts in North America—one over the east coast, one over the west coast, and two up the middle. However, all birds don't simply fly straight north and straight back the same route. Migration routes vary for different families, or even species of birds. Some species make a loop in their annual migrations, going back a different way in the fall than they came in the spring. Some fly in a dogleg, going straight north then taking a tangent east or west. Still others wander over the oceans (pelagic wandering).
With some species, more than one population sometimes leap-frogs over another of the same species, coming from the farthest south and ending up in the farthest northern end of their range. Some species migrate vertically—going to the top of a mountain in the summer and returning to the lower elevations to overwinter. Then there's premigratory movements, in which young birds, as they fledge, disperse in various directions before migrating south.
Sometimes species overstep their usual migration
pattern, going much further south or north than
usual. This pattern, known as "vagrant migration,"
often is a result shrinking prey populations. Snowy
Owls, for example, periodically invade areas off their typical migration route when populations of lemmings, a primary food resource of northern predators, decline. Rarely venturing south of Canada, these birds have been known to venture periodically as far south as South Carolina.
While bird enthusiasts along the coast can see huge flocks of sea and shore birds making their way north, along with a host of warblers and other terrestrial birds, we here in the Piedmont must settle for primarily birds of field and forest. That doesn't exactly make for shabby birdwatching, since the central Appalachians boasts some of the most diverse ecosystems and therefore attract enough migratory species to keep any birder happy. Of the birds that keep traveling north, most start arriving in Rappahannock at the end of March and have left the county by the end of May.
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Indigo bunting. Photo by Bruce Jones. |
Among songbirds, the warblers (as a group) are the stars of spring. The combination of intricate, melodious song, bright plumage (usually shades of yellow and black), and the fact most don't stay long makes them the prize sighting for most birders. It's also challenge to tell the many species of warbler apart, which usually requires good hearing more than good eyesight.
The warblers are certainly not the only songbirds that attract attention here in the spring. The orchard oriole, scarlet tanager, indigo bunting, rose-breasted grosbeak, and cedar waxwing are no bums in the plumage department. And the oriole, among others, has a wonderful, haunting tone to its song, even if it's less intricate than that of the warblers. During the peak migration times, the county is filled with wondrous song and color, and birdwatchers are constantly craning their necks searching the treetops or and peering through thick shrubbery to try to connect the song with the bird. With luck, a birder might see many other species of songbirds (see box), along with ruby-throated hummingbirds, hawks, owls, ducks, geese, and others.
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Prothonotary warbler, a bird scarce in Rappahannock County.
Photo by Bruce Jones. |
A great way to see birds and other wildlife is to follow the Virginia Birding and Wildlife Trail, a program of the Virginia Department of Game and Inland Fisheries. Caledonia Farm, featured in the February 6 issue of Rappahannock News, is the first spot in the Mountain Area of the Trail. Caledonia is a working farm and B&B, with plenty of fields, edge ecosystems, and forest and ponds to attract many species of birds in the spring. The Trail is not an actual footpath but a series of stops through different areas of the commonwealth that offer good wildlife viewing opportunities. The other two areas of the trail are " Piedmont" and "Coastal."
The trails are patterned after a concept started in Texas, along the Gulf Coast. As the Rappahannock News reported in the earlier article, former Governor Mark R. Warner was instrumental in the creation of the Trail. (For more information on the Trail, go to www.dgif.virginia.gov; for a list of all Virginia birds, go to http://www.virginiabirds.org/StateList.html.)
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| Rose-breasted grosbeak. Photo by Bruce Jones. |
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RLEP's Biodiversity Task Force is sponsored a Spring Bird Walk at Caledonia Farm at 8 a.m. on May 20. The walk was led by Shenandoah National Park ecologist Alan Williams, who helped attendees identify bird species and talk about migration. While some of the early migrants will have already left to continue on their journey north, others will be nesting here in Rappahannock, including the cerulean and blackpoll warblers, the American redstart, and the yellow-throated and red-eyed vireos.
On a recent reconnoiter of the farm, Williams spotted several migrant species—including phoebes, redstarts, kingbirds, warblers, redwing blackbirds, and brown thrashers—along with many that live here year round. With the mixed ecosystems on the farm, attendees should see and hear a good variety of bird species. Other wildlife, particularly butterflies (many of which also migrate), are also likely to be on view.
With no Global Positioning Systems at hand, just how do songbirds find where they're going—especially since they migrate at night? During the walk, Williams will explain how and why birds migrate, and how important it is to conserve the ecosystems where they stop along their migratory routes.
Williams, who has worked on ecology projects in Central America, will explore the connection between coffee growing and our migrant birds. Maggie and Kenny Rogers, of Central Roasters, donated coffee grown in bird-friendly conditions from that area for the event. For several reasons, we're asking that attendees for the walk not bring small children or pets. The walk was free, but to keep the group size small, reservations were required.
Please check for more news on this and other Biodiversity Task Force events or contact Pam Owen at 540-675-9989 or e-mail Biodiversity@RLEP.org
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