Most bird species in North America mate for a single breeding season. Some may team up again the following year, just because both stay in - or return to - the same territory. Fewer than one-fifth of Song Sparrow pairs are reunited. Hawks, eagles, and ravens have wide territories, thus few contacts with the opposite sex. Maintaining a relationship through the winter may assure breeding in the next season.
Mating for Life
Written by Dennis Paulson
This is BirdNote. [Common Raven croaking]
Mating for life may be the human ideal, but most bird species in North America mate for a single breeding season. Some may team up with the same mate the following year just because both stay in — or return to — the same territory. But such togetherness is relatively rare.
Because most birds of the north-temperate zone migrate, remaining in touch with a mate throughout the autumn and winter is difficult. For instance, fewer than one-fifth of Song Sparrow pairs are reunited. [Song Sparrow song]
For long-term fidelity, look among the larger birds. Large resident birds such as hawks, eagles, and ravens have wide territories, meaning few contacts with the opposite sex. Maintaining a relationship through the winter may assure breeding in the next season. You'll often see such birds in pairs throughout the year. [Ravens clucking]
Most seabirds meet and breed in colonies. But Marbled Murrelets, little relatives of puffins, breed inland in old-growth forests. They have no chance to meet each other in a colony. So when a male and a female get together, they stay together. [Marbled Murrelet calls]
In the animal realm, birds still provide the best examples of seasonal mate fidelity. Most birds form devoted pairs for at least each breeding season, not something that can be said for most mammals. For BirdNote I’m Michael Stein.
Calls of the birds provided by The Macaulay Library at the Cornell Lab of Ornithology, Ithaca, New York. Common Raven recorded by R.S. Little, Song Sparrow by G.A.Keller, Marbled Murrelet by K.S. Nelson and ambient created from R.S. Little.
Producer: John Kessler
Executive Producer: Chris Peterson
© 2015 Tune In to Nature.org 2017/2019 Narrator: Michael Stein