Feathered tourists bypass Dollywood, head for a sky near you
Songbirds à Go-go
by Rikki Hall
Did you hear an unfamiliar birdsong this morning? How about tomorrow morning? Everywhere in Knoxville, the odds of hearing new and unusual birds are as high as they get all year long. Migration north is at full throttle.
Scarlet tanagers are filling the oaks of South Knoxville, warblers the elms of Oakwood. They are headed northward and up, looking for a patch of woods rich enough to raise a family in. They wintered in Central or South America or the Caribbean. If you buy shade-grown coffee, birds passing through our region now are the ones that benefited. If you avoid beef or wood that may have come from rainforests, it is warblers, vireos, thrushes and hundreds of tropical species that don’t bother to fly north that you are helping out.
Not just the songs of migratory birds are beautiful. Blackburnian warblers have such brilliant throats, they look like flames hopping around treetops. Magnolia warblers accentuate their white, yellow and gray bodies with bold black necklaces. Even if migratory birds were not critical assets in controlling insect populations in our forests, people would want to conserve them just because they are pretty.
A few decades ago, many migratory species were declining. Addressing that problem required diverse and cooperative efforts on many fronts. Nations throughout the Americas set aside public parks and private conservancies where these birds live. Consumers put pressure on corporations to be better stewards of forests. Laws were passed regulating pesticides and protecting plants and animals from extinction, and the results are encouraging. Population declines in forest birds have slowed and even stabilized.
Because of these efforts, you still have a chance of hearing the song of most any eastern warbler during migration. You might hear the high whistles of a Cape May warbler on its way not to New Jersey, but Canada, or the rapid, jumbled chatter of a Canada warbler on its way to Mt. Sterling or, yes, Canada. Even the rarest of North American warblers, the Kirtland’s warbler, was spotted in 1997 on land that is now part of Ijams Nature Center.
The Canada warbler is one of several species associated with eastern hemlocks that may suffer declines as that tree succumbs to adelgid infestation. Loss of breeding habitat is the primary threat to most birds, and hemlocks are a favored nesting tree for some migrants. Other threats to migrating birds include poisonings, usually inadvertent, by pesticides and herbicides and destruction of wintering grounds, but destruction of breeding territory is hardest to overcome.
There is not much breeding habitat left for warblers inside the city limits, but any place with mature native trees might serve as a stopover during migration. Migrating birds fly at night and spend their days in trees refueling on caterpillars and crickets. They rest briefly in the mid-day heat, but true sleep is not possible while the hormones that spur migration are coursing through their veins.
Downtown lost what little appeal it had for migrating songbirds when trees were cut around the federal courthouse, along the route of the Hall of Fame flyover and in Krutch Park. Birds crossing the river from South Knoxville detour either west through campus or east through Morningside, and the most likely sighting of a migrant downtown is a dead ovenbird on a sidewalk beneath a tall, glassy building. Nighttime collisions, like predation by hawks and owls, are part of life for migrating birds.
Most of the birds that make it over or around downtown wind up on Sharp’s Ridge, the hill in North Knoxville covered with transmission towers, whose guy-wires also claim a few nighttime victims each year. There is a small city park up there and an access road for the towers, and it is a prime birding spot. The Knoxville chapter of the Tennessee Ornithological Society ( www.tnbirds.org/KTOS.html ) starts field trips from the Ranger’s House at 8 a.m. each Thursday between now and May 11, and the public is welcome to tag along. Bring binoculars and plan to spend a couple hours watching and listening and scurrying up and down the road as people spot new birds. If you can’t free up a Thursday morning, there are mobs of birders, novice to expert, up there every other morning during migration as well.
If there are mature trees in your neighborhood, you can probably do some decent warbler watching in your backyard. Spotting these tiny, active birds can be frustrating, but listening to them is easy. Keep a window open near your bed and let the birds serenade you awake. Their sweet melodies are a reminder of why it is important to be mindful of our impact on nature. Cardinals, thrashers, titmice and the other year-round residents are singing as well, but one of the singers outside your window may have flown a thousand miles to sing for you, and he has a thousand miles to go before his journey is done.
Rikki Hall is managing editor and publisher of Hellbender Press , a non-profit environmental education journal.