The Mourning dove
By Jeanette Rive
The poor city or Rock pigeon – a bird we love to hate: intrusive, annoying, dirty, damaging to buildings and potentially disease carrying – but they have been cohabiting with humans for some 5,000 to 10,000 years. They have been kept as pets, used to send messages and for food. This misunderstood bird, in spite of not commanding any respect from us, is clever, interesting and a superlative flyer, reaching speeds of up to 88 kph. Their great navigational abilities allow them to find their way home from more than 4,000 km away, creating a map and sensing a magnetic field, they are guided by the stars and sun and follow land and water formations.
A relative of the now extinct passenger pigeon is the much more appealing Mourning dove, one of the most widespread species of bird all over North America, along with the American robin. We find them in our gardens, usually in pairs, sitting on a fence, roosting in a tree or foraging on the ground, their cooing sound often mistaken for an owl in the predawn hours. If they are startled, they suddenly take to the air, the rapid beating of their wings making a whistling sound as the air rushes through the feathers, causing them to vibrate. It’s a dove’s alarm system, warning others of danger.
Doves have several unique characteristics. Most birds sleep with their heads tucked under their shoulder feathers. Doves will hunker down, resting their head between the shoulders close to the body. They are also among the few birds that use suction in drinking and can suck up their daily water requirement in 20 seconds. Most birds fill their bill with water and then tilt their heads back to swallow.
Doves evolved specifically for ground foraging, which is where we mostly see them, often under our feeders, picking up stray seeds and then flying up to a fence or a tree, storing the seeds in their crop (an expandable part of the top of the esophagus) to digest later in safe surroundings. A record 17,200 bluegrass seeds were once found in the crop of a Mourning dove! Weighing about 128 grams, they eat about 20 percent of their body weight in seeds daily, the equivalent of about 25 peanuts!
Why is it called a Mourning dove? Their cooing sound can be interpreted as sad and mournful. To others it is a gentle comforting sound: coo-OOoo- woo woo woo. The males coo to attract a female. Similar in appearance, the female is a little smaller than the male. Mourning doves are monogamous and courtship consists of mutual preening of each other’s neck feathers, progressing to up-and-down head bobbing in sync while grasping each other’s bills.
What do flamingos, male emperor penguins, pigeons and doves have in common? They are the only birds that produce a substance called “crop milk” used to feed their young. It is a suspension of protein- and fat-rich cells secreted from the lining of the crop. Both sexes of doves and pigeons produce it. It sustains the squabs, as dove chicks are called, for the first week of life until they can digest an adult diet. Mourning doves can produce up to six broods a year, laying two eggs at each brood; there is only enough crop milk to feed two chicks. When crop milk begins to be produced a few days before the eggs are due to hatch, the parents stop eating seeds so as not to contaminate the milk. The nesting site in a tree or shrub is chosen by the male, subject to approval by the female. It’s not a substantial nest, made up of twigs and pine needles. The male stands on the female’s back as she is building the nest, perhaps supervising the construction! Both parents incubate the young, the male taking most of the day shift, the female the rest of the day and overnight. Mourning dove squabs fledge after about two weeks but are fed by the parents for a few weeks.
The robins along with Red-winged blackbirds are back. As are House finches with their distinct red heads and breasts. It must be spring! Enjoy the returning life to our backyards.
Jeanette Rive is a Glebe bird enthusiast and Glebe Report proofreader.
Photo:
Jeanette Rive