Red-breasted Goose - Notes on Biology & Propagation

Abstract

Considered by many people to be the most beautiful goose species in the world, the Red-breasted is also one of the least numerous forms of waterfowl both in the wild and in captivity. It belongs to a group of geese we call Branta, and this genus also includes the Canadas, Brant, Barnacle, and the Hawaiian Nene Goose. All of these have been placed together because of characteristics they share in common, yet they are quite different, too; each one specialized in its own way for coping with its environment and way of life.

While the Nene Goose possesses the most specialized adaptation for dealing with the physical environment, that of having strong legs and tough, claw-like feet for climbing around on lava flows, the Redbreasted is, perhaps, the most unique of the group in terms of its nesting ecology and interspecific relationships. Most notable is the habit they have of placing their nests in close proximity to those of Peregrine Falcons and other birds of prey.

Now, this would at first seem an unwise and unproductive strategy for reproduction given the predatory reputation of the Peregrine. However, it appears these two species have evolved a mutually beneficial arrangement whereby the Falcon protects the Red-breasted by "dive bombing" and driving off intruding Arctic Foxes and other predators, with the ever vigilent and vocal Redbreas teds providing an added measure of surveillance and warning for both species to the approach of menacing visitors.

In the region where Red-breasted Geese nest, which is limited to a very small area in the Central Siberian Arctic, there is reported to be a sizable Arctic Fox population. There are very few locations the Red-breasteds can choose for nesting that are inaccessible to foxes and this is, no doubt, the reason why this most unusual antipredator adaptation has come into being. There are, of course, many other species known to seek protection by nesting near another species.

Examples of this are ducks making their nests in Tern colonies, and Sandwich Terns nesting in Black-headed Gull colonies. However, the Redbreasted/Peregrine assocation is more unusual in that one of them, and especially its young, may be considered a more likely prey of the other!

Very little is known of the nesting biology and population status of Redbreasteds on their breeding grounds. Russian biologists A. Krechmar and V. Leonovich, who were apparently the first to observe the antipredatory behavior just described, are among the few to have visited their breeding grounds for the purpose of gathering information on their biology. They found Red-breasteds nesting close by at 19 of 22 Peregrine nests that were located, and these were anywhere from five to 300 feet from the nesting Peregrines. A few of the geese were also found nesting near the nests of Herring and Glaucous Gulls and that of the Rough-legged Buzzard.

Located conspicuously on the open tundra, the nests are placed on sites that are relatively high and dry and which are near water. The size of the clutch is normally five to six eggs, but a range of from three to nine has been reported. Incubation takes 24 to 25 days and is performed by the female only, with the gander keeping watch nearby.

On the Taymyr, Gydan, and Yamal Peninsulas in Central Arctic Siberia where the species nests, the summer season is very short, and the birds must be hatched and fully fledged within a few short weeks. Most Redbreasteds are hatched by late July and are grown and flying by the end of August or first part of September.

A dramatic decline in the Redbreasted population has occurred over the past several decades. Although reliable information on their status is not available, several estimates have placed the wild population at from 25,000 to 30,000. This number may be considered alarming ~hen compares to the population size existing in the early 1950s of from 40,000 to 60,000.