I have been reading great reports of interesting fall migrants on Monhegan Island and at other migration hotspots. Any Maine birder would be thrilled to see a White-eyed Vireo or a Lark Sparrow, both of which have been reported this autumn. But there is pleasure in seeing the everyday birds as well, even pigeons.
The standardized name for our pigeon is Rock Pigeon. They are well known to birders and non-birders alike. How can you avoid seeing pigeons in any city?
Wild Rock Doves were likely found from Scandinavia south through most of Europe, and further south to equatorial West Africa. Wild populations likely occurred in Russia south to Pakistan and India in Asia. We will never know the full range of wild Rock Doves because these birds were first domesticated 5,000 years ago. Captive pigeons were transported around the world. Domesticated birds readily become feral, hence the pigeon populations in your local park or on farms.
Wild Rock Doves nest in crevices and caves on rocky cliffs near short, shrub vegetation. Feral pigeons in North America also occur in similar types of habitats, where tall buildings substitute for cliffs.
In North America, the first domesticated pigeons were brought to Atlantic coastal villages in the early 17th century. These domesticated pigeons gave rise to feral populations, which have spread across the continent. Rock Doves now occur throughout all of the 49 continental states, the southern portion of all the Canadian provinces and throughout Central America and the West Indies.
Among wild populations, nine subspecies have been described. The differences among subspecies are based on color and size. However, these differences in color bear no relationship to the feral pigeons we see. Through domestication, pigeon fanciers have bred Rock Doves for particular colors and plumage anomalies. These variants, called sports, were prized by upper crust British gentlemen in Victorian England. Charles Darwin was a pigeon fancier.
Careful study of pigeons can be a rewarding experience. A number of interesting behaviors are associated with nesting. Pigeons mate for life. Eggs may be laid as early as February and as late as October. From a thorough study of pigeons in Kansas, we know some birds have over six nests per year. That’s some serious dedication to family life!
The formation of the life-long pair bond occurs through a series of displays. This courtship begins with a bout of bowing and cooing, in which the male stands erect, inflates his crop, fans his tail and struts around in a circle. He bows his head and neck while giving a coo call.
The next stage in courtship is heteropreening (literally preening the other) or nibbling. The male preens the female first and then the female returns the favor. Next, the female solicits food from the male. The male obliges by regurgitating seeds from his crop.
The female then accepts the advances of the male. She crouches with her wings half-raised and mating takes place, lasting only a second or two.
After mating, the male gives a display in which he stands erect and walks a few steps. He then launches into a display flight in which the wings are clapped together twice above the back.
Aggressive interactions also take place with characteristic displays. When a male approaches another male’s mate, particularly if the female is receptive, the female’s mate may crouch and shift the position of its wings. This behavior conveys aggression. The intruder may be pecked on the head. Other intruders may be driven, a behavior involving a type of chasing in which the intruder is literally pushed away.
The male may also give a threat display by standing horizontally, inflating its crop and walking around in circles. As the male walks, it gives a display call and raises its wings.
[First published on September 30, 2012]