The Ovenbird: Nature's Teacher
Photo courtesy US Fish and Wildlife Service
by Jean Deo
"Teacher. Teacher! TEACHER!"
While hiking through northeastern forests in spring and early summer, you will likely hear the distinctive song of the male ovenbird. Their song becomes louder as they sing its notes, as if they have an important message to convey to forest dwellers. And they do. For other birds that try to move into their territory, ovenbirds use their song to shout, "Get away! This spot is mine!" To female ovenbirds, their song says, "Hey, good looking!" I like to think that ovenbirds also have a message for us, the hikers and nature enthusiasts. Their message is reflected in the phonetic representation of their song-"teacher!" as they offer us valuable lessons in bird migration and conservation.
Ovenbirds are small, olive-brown birds whose white breasts and sides are streaked with lines of black dots. On their heads, they have two black stripes bordering a tawny orange patch. Every spring, ovenbirds migrate from Mexico, Central America, and the Caribbean to the northern United States and Canada. Hikers in the tri-state area should watch for the spring arrival of ovenbirds from late April to mid-May. When looking for this bird, focus your search on leaf-litter-covered floors of large broad-leafed and mixed forests, as ovenbirds spend much of their day eating insects and other small organisms in the litter.
Hear the Ovenbird's song and learn more about them at these great sites!
By late May, ovenbirds have reached their breeding grounds, which range from Tennessee to northern Saskatchewan, and have started establishing territories, which are habitat patches that they use for food, nest sites, and mating. Males arrive one to two weeks before females to set up and defend territories from competing males. To defend a territory, males often counter-sing, in which one male's song is immediately followed by a neighbor's song. While hiking during this time of year, you will repeatedly hear males singing the "teacher-Teacher-TEACHER" phrase. Although loud, these songs are misleading as these birds seem to "throw" their voices and may be farther away than you expect.
Ovenbirds breed from late May through early July. Females preferentially select mates with longer and higher quality songs because these males often have superior territories, more effective defense strategies, and better health than males with shorter, disjointed songs. Using dead leaves as construction material, females build domed nests with side entrances that resemble Dutch ovens (hence their name). Ovenbirds often place these well camouflaged nests on the ground in small fern patches, at the base of trees, and near trails. If you spot an ovenbird on her nest, the female will either sit very still or walk away from the nest while feigning a broken wing injury.
In the late summer, ovenbirds sing less as they replenish their fat stores for migration. From August to October, ovenbirds leave their breeding grounds and start flying south. Stopover sites, habitat patches in which ovenbirds stop temporarily to rest and eat, are vital to their survival on these long journeys in which ovenbirds face countless dangers, including predation and storms.
Aside from the innate dangers of migration, the populations of ovenbirds are threatened by habitat fragmentation. Depending on the population, ovenbirds require minimum forest sizes ranging from 100 to 885 hectares (about 250 to 2,200 acres). In smaller forests, ovenbird populations rapidly decline because of higher predation rates and lower food availability. In their breeding range, brown-headed cowbirds, a parasitic bird species that replaces host eggs with its own eggs, can significantly decrease ovenbird populations, especially in smaller forest patches in which cowbirds have easier access to ovenbird nests. To protect these species, conservationists focus on preserving habitat, controlling cowbird populations, and learning more about other factors such as disease and pollution that affect ovenbirds.
The journey of the ovenbird and the challenges facing its survival are common themes among migratory birds. As nature enthusiasts, you can play an important role in migratory bird conservation by supporting local efforts to preserve natural habitats and by passing along the ‘teachings' of ovenbirds to others. In this way, the very important message that ovenbirds sing will be carried to those far outside the forests on which ovenbirds and so many species depend.Jean Deo is a Ph. D. candidate in the Graduate Program in Ecology and Evolution at Rutgers University.