By Mike Burke
For the Bay Journal News Service
The forest was cool and had the sweet smell of a recently fallen tree and the duff beneath our feet. In the dappled sunlight we could see midges swarming. Near and far, we heard birdsong. One of the delights of birding is opening our senses to soak in the natural world. This was a special place, and we were immediately enchanted.
A very loud and persistent teacher-teacher-teacher stood out among the avian tunes. The refrain was rapid-fire. Trusting my ears, we followed the sound. The bird obliged by repeating its song again and again. Carefully, we moved closer until I spied the singer on a low branch.
The ovenbird (Seiurus aurocapilla) is surprisingly small for having such a powerful voice. Its length is 4.–5.5 inches, and it weighs up to an ounce. The bird spends most of its time on the forest floor, looking for insects to eat. Here at the Patuxent Research Refuge, just outside Laurel, MD, it had found an ideal summer home.
The ovenbird’s throat, breast and sides have bold black streaks that contrast sharply with the bright white undersides. The black-on-white pattern forms a chevron on this warbler’s belly. On top, it is a uniform greenish brown from head to tail. A white eye-ring is distinctive, but the best field mark is a broad orange stripe, bordered by jet black stripes, on its head. The sexes look alike. It’s a handsome warbler, but its good looks have a hard time competing with the male’s voice.
This bird’s song is incredibly fast. It repeats the “teacher” phrase as many as six times per second. And males on breeding territory can sing constantly. This certainly helps in finding the bird, especially as it isn’t easily flushed by humans. Just follow the sound and approach slowly.
Ovenbirds require large swaths of undisturbed forest. The Patuxent refuge offers 13,000 acres of mostly hardwood or mixed deciduous-coniferous tracts. The conditions are ideal for ovenbirds, with plenty of mature trees, a closed canopy and lots of dead leaves on the forest floor. Ovenbirds live deep in the woodlands, where they feed, raise their young and find places to sing, sing, sing.
These are neotropical migrants. Each spring they leave the tropics and move through most of the eastern United States, reaching Virginia in April. Quickly thereafter they spread across the Chesapeake Bay watershed. About one-third of the ovenbird population stops to nest in the northeast quadrant of the U.S., from North Carolina over to Missouri and north to the border. According to the Breeding Bird Survey, the remaining two-thirds breed in a huge band across the Canadian provinces, from the Atlantic Maritimes to the eastern edges of British Columbia.
The female ovenbird assumes almost all breeding duties. She starts by fashioning a canopied nest on the forest floor. The hidden entrance is tilted slightly downward. Inside, she makes a small, shallow nest, which she lines with deer or horsehair. The entire structure is meticulously woven over five days or so. The nest is nearly invisible from above, shielding chicks from overhead predators like hawks and crows. The finished home looks like an earthen oven (without a chimney). That resemblance inspired the bird’s name.
She lays three to six eggs, typically four. Eggs require 12–14 days of incubation, all provided by the female. Hatchlings are born helpless but develop quickly. Seven days after hatching they begin to leave the nest, hopping and fluttering about. Both parents feed the young.
Ovenbirds eat what they find in the leaf litter: beetles, ants, fly larvae and the like. They can be flexible, too. An outbreak of insects feeding on leaves will send ovenbirds flying up to branches to feed. In cold weather, when insects are scarce, they will also eat berries.
The population of this warbler has held relatively steady for decades — a rarity in a world of dramatic declines in avian populations. A major threat looms, though. Forest fragmentation disrupts the territory that the birds need. Large stands of woodlands suddenly sliced up by roads or powerlines become noticeably less productive. Construction that carves out substantial stands of trees can have the same effect.
Development threats at Patuxent are constant. A proposed MAGLEV line would take up to 328 acres off a corner of the refuge. A widening of MD Route 197, a perennial threat, would rip through the heart of Patuxent (including several avian research facilities).
Meanwhile, there was a plan afoot last year to sell an unused 105-acre wooded parcel of the NASA Goddard Space Flight Center, which provides a buffer on the refuge’s southwest boundary, to the highest bidder (most likely a developer). The plan has been blocked for now, but the threat still exists.
The ovenbird is not the only bird being threatened at Patuxent. The scarlet tanager, the unofficial mascot of the refuge, also breeds there. The same holds true for the brown creeper and other species that need plenty of undisturbed space to breed successfully.
We need to put an end to such threats. We can start by permanently protecting our federal resource lands. States and localities should follow suit. In fact, we should be seeking opportunities to expand these irreplaceable forests, wetlands, prairies and waters. We have already lost too many.
President Biden has set a goal of providing such protection to 30% of America’s land and waters by 2030. It is a worthy goal. And surely one the ovenbirds would loudly endorse.
Mike Burke, a Bay Journal columnist, is an amateur naturalist based in Maryland, having retired from a career that toggled between Capitol Hill and the U.S. Environmental Protection Agency. This article first appeared in the June 2022 issue of the Bay Journal and was distributed by the Bay Journal News Service.
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