Biological Exuberance: Animal Homosexuality and Natural Diversity

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GALAH

IDENTIFICATION: A medium-sized parrot (about 14 inches) with a pale pink forehead and crest, rose-pink face and underparts, and gray upperparts. DISTRIBUTION: Interior Australia. HABITAT: Savanna woodland, grassland, scrub. STUDY AREAS: Healesville Sanctuary and Monash University, Victoria, Australia; Helena Valley, Western Australia.

PEACH-FACED LOVEBIRD

IDENTIFICATION: A small parrot (6 inches) with a short tail, green plumage, blue rump, and a red or pink breast and face. DISTRIBUTION: Southwestern Africa. HABITAT: Savanna. STUDY AREAS: Cornell University, New York; University of Bielefeld, Germany.

ORANGE-FRONTED PARAKEET

IDENTIFICATION: A small parrot with green plumage, a long tail, and an orange forehead. DISTRIBUTION: Western Central America from Mexico through Costa Rica. HABITAT: Tropical and scrub forests. STUDY AREAS: Near Managua, Nicaragua; University of Kansas and University of California—Los Angeles; subspecies A.c. canicularis and A.c. eburnirostrum.

Social Organization

Galahs and Peach-faced Lovebirds are gregarious birds, gathering in large flocks that can number up to several hundred in Lovebirds and up to a thousand in Galahs. They typically form mated pairs, and Peach-faced Lovebirds usually nest in colonies. In addition, there are nomadic flocks of juveniles and younger nonbreeding adult Galahs. Orange-fronted Parakeets are also highly social, traveling in groups of 12-15 birds (often composed of mated pairs) and sometimes forming flocks of 50-200. During the breeding season, pairs generally separate from the flock to nest, although they periodically recongregate in small groups.

Description

Behavioral Expression: Galahs of both sexes form stable, long-lasting homosexual pairs that participate in courtship, sexual, and pair-bonding activities. Same-sex bonds are strong, often developing in juvenile birds and then continuing for the rest of their lives (as do most heterosexual bonds). Homosexual pairs of at least six years’ duration have been documented in captivity. If one partner dies before the other, the remaining Galah may stay single or may eventually form a homosexual (or heterosexual) partnership with another bird. Pair-bonded Galahs almost always stay close to each other (rarely more than a few inches apart), feeding and roosting together both day and night. When one bird flies to a new location, it calls after its mate to join it, using a special two-syllable warbled call that sounds like sip-sip or lik-lik. If another bird intrudes between them, both partners threaten the intruder and may force it to leave by edging it out or simultaneously stabbing their beaks at it. Pair-mates spend considerable time preening each other; this intimate behavior, sometimes known as ALLOPREENING, involves one bird lowering its head in front of the other, allowing its mate to gently nibble and run its bill through the feathers. After a short time the birds switch positions, and often this develops into a playful fencing bout, in which the birds gently clash beaks and dodge each other.