What better bird to feature in the month of St. Valentine than our native lovebird, the mourning dove, Zenaida macroura. The mourning doveís courtship behavior and devotion to each other are legendary, and their breeding season will begin soon.
Some of the male mourning doves have been able to remain here through our white winter, if they have found a friendly bird feeder or a snow-free granary. These males have a major advantage: they can ferret out the best nesting sites before the others return from their wintering grounds as far south as Panama. A male will mark his territory and proclaim his intent with his recognizable, romantic, plaintive coo.
He perches with neck arched, and it appears as though every muscle is tense in an effort to make a perfect performance that will entice his future mate.
The female responds with a thinner and more variable song. She chooses the nest site from within the territory the male has claimed. She will generally choose a crook of a tree, a flowerpot or even a hollow on the ground for their nest, which is made of an assembly of twigs, grass stems and pine needles.
The nest is made over two to four days with quite a bit of ritual. Each time the male returns with a twig there is an exchange of caresses and coos, followed by preening and feeding of the female by the male. The female then weaves the stems into the nest one by one.
The nest is unlined because the eggs do not need insulation, since the devoted pair never leaves the nest unattended. The male generally incubates during the day and the female at night. When this changing of the guard occurs, it is also accompanied by gentle nibbles and shared preening. The bonded pair can also be observed grasping beaks and bobbing their heads up and down in unison.
Mourning doves can store large quantities of seeds in their crop, an enlarged portion of the esophagus, so they do not have to leave the nest frequently for foraging.
Because the nest is always occupied by one of the parents, the eggs do not need to be speckled or camouflaged. Mourning dove eggs are white, and the clutch size is generally two. Because of constant incubation chicks hatch within two weeks. Both parents immediately provide their hatchlings with rich crop milk.
Crop milk is the consistency of cottage cheese and has more protein and fat than mammalian milk. Parents open their beaks, then the hatchling sticks its head into the open mouth and consumes food right from the parentís crop. They eat seeds from the parentís crop in the same fashion. Because of all this rich food and constant attention, the young are ready to leave the nest in two weeks.
With this quick turnabout time from egg to fledgling (about four weeks), the devoted pair can begin a new brood. In Montana, mourning doves can raise up to three broods during the nesting season, which is from April through September.
The mourning dove is the only native North American bird to breed in every contiguous state.
Their U.S. population is estimated to be more than 400 million, but despite these numbers, their lives tend to be short and difficult. In any given year, more than half of the adults and two-thirds of the first-year birds will die. It is a good thing that they are adapted to produce many broods per season for their population to keep up with this mortality rate.
The mourning dove is a legal game bird in most states and on their wintering range in Latin America. In the U.S. alone, hunters take more than two million birds annually. Doves also face the less visible problem of lead poisoning because they forage on the ground; in heavily hunted upland bird areas, they wind up eating fallen lead shot. It is unfortunate, then, that last March, Ryan Zinkeís very first act as Interior Secretary was to rescind an order that banned the use of lead ammunition on U.S. Fish and Wildlife Service lands. Predators, including house cats and bad weather, are also threats to these gentle birds.
Some have feared that the rapid increase in numbers of the non-native Eurasian collared-dove might have negative effects on our native doves. The mourning doveís long slender tail readily distinguishes it from the square-tailed collared-dove. The Eurasian collared-dove is also a bit larger and has a dark ring around the back of the neck, as opposed to the mourning doveís sweet cheek smudges. Over the past decade, in spite of the invasion of the Eurasian collared-dove, the population of our native mourning dove seems to have remained steady. We hope that they continue to flourish.
If you would like to attract these graceful, melodious birds to your yard, you can plant dense native shrubs or evergreens, provide seeds on a platform feeder and keep your cats inside. Then anticipate the soulful coo of this tender bird as courtship begins.