This morning, March 28, at daybreak, I heard a mourning dove cooing for several minutes from on top of the outside part of our bedroom air conditioner, as I have every spring for years. Then I went into the bathroom and heard a group of house sparrows chirping and scrambling on top of the outside part of the air conditioner in that room, as I have for several years. Both these adaptable, permanent resident species will attempt to nest on the conditioners, or between them and the window sills. Instantly, I realized the many similarities mourning doves and house sparrows have, though they have a few differences, too.
Mourning doves are native to North America, but house sparrows were introduced to this continent from Europe. The doves probably lived in woodland clearings originally, where there were weed and grass seeds to eat. The house sparrows long ago adapted to agricultural fields and horse stables in Europe. Doves coo and are much bigger than the sparrows. The sparrows chirp. And there is where the differences between these species ends.
Though mourning doves and house sparrows look a lot different, they have many similarities.
Both species are brown with darker markings, which allows them to blend into their backgrounds so they are not obvious to hawks, cats and other predators. However, in spring, males of each species acquire subtle colors that show their readiness for breeding. Male doves get a sheen of pink on their necks while male house sparrows have black bibs.
Males of both species have courtship displays to coax their mates to copulate with them. Male sparrows flatten their bodies, spread their wings a bit and hop around their mates, chirping all the while. Male doves coo, but also engage in courtship flights, with several deep flaps of their wings, then soaring in a circle over their territories.
Both these species with abundant numbers are well adapted to suburban areas with their buildings, trees and shrubbery for nesting, and grain field banquet tables in agricultural areas near the suburbs, which is an abundant habitat combination here in Lancaster County, Pennsylvania, therefore the abundance of birds of both these species. Large habitats potentially make the success and abundance of every form of life.
The sparrows build bulky grass nurseries in sheltering crevices in the buildings while doves nest on ledges on the buildings, and in trees and shrubs. Doves build flimsy cradles of grass, straw or twigs, many of which fall apart in high winds. Doves are often better off building nests on buildings or in other birds' sturdier nurseries.
The vocalizations of both species are heard much of each day, every day through summer. Doves raise two young per brood, but have successive broods from March through September. Each pair could rear 12 young a year, but accidents and predators take their tolls. House sparrows generally hatch two or three broods of five youngsters each, in a summer.
Mourning doves and house sparrows eat grain and weed and grass seeds in fields near their nesting sites, though the sparrows also consume insects in summer when that food is abundant. Both these species are prevalent in harvested grain fields to feed on the seeds that fell to the ground. And both kinds consume seeds at bird feeders in suburban lawns the year around, dominating some of those feeders with their numbers.
After a summer of multiple broods of young, both species form larger and larger flocks, by the score or even hundreds, late in summer and into early autumn. Both types of birds range across harvested fields to pick up seeds and grain with their beaks, dominating those croplands. The doves are even common game birds in the croplands during September.
House sparrows and mourning doves may look different, but they have a lot of similarities. And these adaptable species have the best of two human-made worlds- suburbs and fields, including here in Lancaster County.
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