Chances are you've heard of the red-winged blackbird. But what about the black-winged redbird, or the firebird, or the scarlet sparrow? These exotic-sounding names describe one of South Dakota's most stunning breeding birds - the scarlet tanager (Piranga olivacea).

We like to consider birds that reside in South Dakota as "our" birds. But scarlet tanagers are among the approximately 650 bird species called neotropical migratory birds. These birds breed in the United States and Canada, then travel to wintering grounds in the neotropics, which include the tropical portions of Mexico and Central and South Dakota. As many as two to five billion individual birds migrate to and from the tropics each year. Unlike a resident bird with a relatively small home range, neotropical migrants must have suitable living areas on their breeding grounds, at wintering sites and at migratory stops in between.

Nearly a third of South Dakota’s breeding bird species are neotropical migrants. They include flycatchers, hummingbirds, kingbirds, swallows, thrushes, vireos, warblers, tanagers and many of our sparrows, hawks, wrens, grosbeaks and orioles. Recent analysis of breeding bird surveys from the 1980s should grab out attention. South Dakota’s neotropical migrant species experienced a 41 percent decline during that decade.

Unlike humans, birds don’t winter in the south to find rest and relaxation, but out of necessity. Most neotropical migrants rely on protein-rich food for sustenance. Birds like robins that can switch to a winter diet of seeds and leftover fruits and berries may winter in such harsh climes as South Dakota or may migrate south during some years. Birds with a year-round dependence on such foods as insects have no choice but to migrate to areas where these creatures abound all year.

The scarlet tanager is a member of North America’s tanager quartet, the others being the western, summer and hepatic tanagers. Of the four, the scarlet tanager travels farthest during migration. When a male scarlet tanager arrives in our state in May, he has journeyed from a wintering home in mountain forests stretching from Panama to Bolivia. He establishes a territory of two to six acres, typically in a dense stand of mature deciduous trees. The female arrives at the breeding territory a few days later.

In general, tanagers are not considered strong or accomplished singers. Their colorful plumage allows visual instead of auditory displays. Tanagers are found in open country or high in the tree canopy, where they can easily see each other. And many tanagers reside as mated pairs throughout the year, making pair bond re-establishment with song unnecessary.

The male scarlet tanager eagerly follows the female, displaying his brilliant plumage while perched below her. Scarlet tanagers apparently don’t know they’re considered mediocre singers, since singing plays an important part in courtship and pair bonding. The male sings almost constantly after arriving on his breeding territory, the pair sings to each other and the female frequently sings as she gathers food and nesting material.

Scarlet tanagers have fairly distinctive roles during the nesting season. The female gathers material to build a nest of twigs, grass and stems, usually halfway up a tree, 20-30 feet aboveground. After completing the nest, she lays three to five eggs, which she alone incubates for about two weeks. Her mate feeds her insects, slugs, snails, worms and wild berries at the nest. The female does most of the feeding of the nestlings, which are cared for in the nest for about two weeks before they fledge.

Successfully producing a brood of young "firebirds" isn’t automatic, of course. Enemies abound, embodied as actual predators and indirect competitors. Blue jays and crows prey on scarlet tanager nests and nestlings. Less common predators are some hawks and owls, particularly the screech-owl.

A more serious threat to nesting scarlet tanagers and many other birds is nest parasitism, particularly by the brown-headed cowbird. Habitat fragmentation is an ominous phrase to many who study and appreciate birds, particularly those species requiring large and intact habitat blocks. When these blocks are fragmented by road construction, land clearing and human expansion, habitat edges increase. Increased edge may increase species diversity, which is not always a good thing. This habitat change favors species adapted to edge habitat (cowbirds) and disfavors species that evolved in large continuous habitats (many neotropical migrants).

As contrasted with the industrious scarlet tanager pair, the cowbird builds no nest of its own. The female carefully watches for a chance to deposit her eggs in nests of other birds. She may eject one or more of the host bird’s eggs. Some birds are more sensitive than others to changes in their clutch of eggs. Although the female scarlet tanager may recognize a female cowbird as a threat, this species is a common cowbird host. The female tanager incubates all eggs in her nest, including those of the invading cowbirds. The cowbird chick is typically larger than the host bird’s nestlings, translating into a bigger food demand and faster growth, all at the expense of the host bird’s chance of replacing itself and its mate through nesting. Cowbirds reportedly parasitize more than 200 North American bird species, contributing to the near extinction of several species.

How is the scarlet tanager doing in South Dakota? This species is primarily a bird of eastern forests and South Dakota is at the western edge of its breeding range. During the recently-completed South Dakota Breeding Bird Atlas project, three scarlet tanager nests were confirmed, the first nests documented in the state since 1924. Nests were found in Marshall, Clay and Union counties. With additional surveys, this species may be found in other forested areas of South Dakota.