Volume 45, Number 2, December 1998:
Feral Pigeons

Text-only version

ISSUE HOME PAGE

ABOUT THIS ISSUE
- about KSN
- about the author

IN THIS ISSUE
- introduction
- origin of feral pigeons
- basic plumages
- mate choice and plumages
- advantages of different plumages
- advantages of choosing different mates
- breeding seasons
- reproducative data
- brood reduction
- living in colonies
- commuter pigeons
- relationships with people
- reference

SLIDESHOW
View all images in this issue.

Updated: March 9, 2005
Send comments/questions to Terri Weast.

Feral Pigeons
by Richard F. Johnston

BASIC PLUMAGES

One conspicuous characteristic of feral pigeons is that they have many more plumage colors and patterns than rock doves, and many fewer than domestics. Wild rock doves have one plumage, the so-called blue-bar plumage (Figure 1). This consists of a pale gray back and wing coverts, two black bars across the trailing edge of the secondary converts, a white rump, gray tail with black subterminal bar, pale gray belly, and a darker head and neck that also has iridescent blues, greens, yellows, and reds. Females are slightly less iridescent than males.

Domestic and feral pigeons may also wear the blue bar plumage, but most are in some other feather coat. A common alternative plumage is checker (Figure 2), which is similar to blue bar but features a graded series of few to many black spots, "checks," on the wing coverts. Also common is theT-pattern plumage (Figure 4), in which the wing coverts are almost entirely dark, with small, pale t-shaped flecks; the remainder of the plumage is also darker, except for the white rump. Bars, checkers and T's may also be in ash red plumage (cover and Figure 3), in which the blue is replaced by a pale red, so that we speak of blue bar or red bar, blue checker or red checker, and so on. Additionally, all of the above varieties sometimes appear with a gray rump.

The darkest plumages are also called spread, in which black pigment is spread all over all feathers. Checker, T and spread individuals are commonly referred to as "melanics," that is, birds that are darker than blue bar pigeons.

White plumages, not true albinos, are common among domestics and uncommon in ferals, although many birds show a few or even several white feathers in an otherwise normal blue or red plumage or any other pattern. Additionally, breeders have established a large number of other colors that breed true - milky, indigo, almond and smoky are examples.

Wild rock doves are almost wholly blue bar in color and pattern; therefore, plumage variation in domestics must have been the result of human preservation of plumage mutants by selective breeding. The range of patterns and colors in free-living ferals, however, is considerably reduced over that in domestics. Such reduction is independent of human selective breeding, and suggests that natural selection has reasserted itself. Consistent with such a suggestion, some of the colors and patterns of domestics come with survival advantages or reproductive penalties and are accordingly either favored or culled from pigeons living in the wild. This should be expected because ferals live under demanding wild conditions.

The most regular consequence of life in the wild is that unusual plumage color and pattern combinations are removed by predators. Many of these, such as house cats, Cooper's hawks, peregrine falcons, or goshawks organize their hunting on the basis of recognizing odd individuals. Successful hunting begins with focusing on one individual, which allows a single bird to be chased from a flock of dozens. One result is that 95% or more of the birds in feral groups will be in blue bar, blue checker, blue T, or spread plumages, with a few o father other possible plumages irregularly represented in the remaining birds.

The proportion of a pigeon population that is in melanic plumage varies geographically: northerly localities have high melanic frequencies, which decline smoothly to the south. For 21 Eurasian localities between latitudes 41 to 62 degrees north, the percent of melanic birds in sample populations shows a correlation coefficient of r = 0.75 with latitude, which means the relationship is not a result of chance sampling.