Post-Breeding Nest Cavity Defense in Purple Martins

Abstract

nor did she make any apparent movements to attract the male. Immediately after giving the last of several headjerk displays, the male strutted from the front of the female around to a position just behind her. The female then responded by crouching low on the ground with her back to the male. Her wings were outstretched and held slightly above the level of the back, with the primaries spread widely apart. The body feathers of the hen were somewhat ruffled in appearance and the tail was closed and shifted over to one side to expose the cloaca. This response is very much like the receptive posture of female Sage Grouse (Centrocercus urophasianus). The male, once the female had assumed the receptive posture, stepped on her back and grasped the feathers of the back of her head in his beak. The wings of the male were extended to the ground on either side of the female, probably to maintain balance. His tail was lowered in an attempt to make cloacal contact. The male then made pushing movements with his feet against the upper back region of the female, with his neck bent forward and pulled down so that his throat was nearly on his breast. Once cloacal contact was established, the treading movements on the female's back continued for approximately 10 sec, after which the male dismounted. He then strutted away in the same vigorous manner displayed in precopulatory behavior. The female after copulation exhibited postcopulatory behavior similar to that displayed by many hens of the Galliformes (Lumsden, 1968, op. cit.). Once the male had stepped off her back, the female moved forward several feet with most of her feathers ruffled, shaking them vigorously as if she had taken a dust bath. Her tail was alternately spread and closed, and her head was in a more vertical position than it was in the receptive posture. The feather-shaking lasted about 15 sec, after which the female spent a short time preening. The male continued to show a high degree of response to sexual stimuli after copulation; i.e., he strutted vigorously, gave several challenge calls, and twice performed display-flights in response to recorded female calls. The female showed no further response.