Display site selection in a ground dwelling bird: the importance of viewshed. (23rd December 2022)

• Record Type: Journal Article
• Authors: Ucero, Alberto; Alonso, Juan C; Palacín, Carlos; Abril-Colón, Inmaculada; Álvarez-Martínez, José M
• Editors: Jennions, Michael D
• Is Part Of: Behavioral ecology. Volume 34:Number 2(2023)
• Page Start: 223
• Page End: 235
• Publication Date: 2022-12-23
• Subjects: Canarian houbara bustard -- Chlamydotis undulata fuertaventurae -- display site -- microhabitat -- visibility; Animal behavior -- Periodicals; Behavior evolution -- Periodicals; Ecology -- Periodicals; Psychology, Comparative -- Periodicals; 591.5
• DOI: 10.1093/beheco/arac112
• Languages: English
• ISSNs: 1045-2249

Abstract

Abstract: We studied the effects of visibility, female and male distribution, microhabitat and distance to human infrastructure on display site selection in a ground-dwelling bird, the Canarian houbara bustard. Using a very high-resolution digital elevation model based on LIDAR technology, and a complete census of the breeding population, we compared 98 display sites with randomly generated sites through generalized linear models. Univariate analyses showed that males displayed at locations that increased their visibility, both at short and long distances. Interestingly, although numbers of females and males around sites did not differ between display and random locations, from display locations males could see more females and males at both distance ranges. The absence of vegetation and stones was also critical as it allowed males to perform display runs on a ground free of obstacles. The amount of trophic resources did not correlate with the selection of the display site itself, though an appropriate vegetation cover seemed to be important at a wider habitat scale. Finally, display sites were farther away than random sites from sources of human disturbance, such as urban nuclei, buildings and tracks. Logistic regression analyses confirmed the importance of viewshed, low stone and vegetation cover, and distance to urban centres and tracks, and model averaging identified short-range visibility and females visible in the long range as the most important visibility variables. These results are compatible with the sexual advertisement and predator avoidance hypotheses. We provide recommendations to ensure an appropriate management of the breeding habitat of this endangered subspecies. Abstract : For a male, choosing a suitable display site is critical to effectively transmit his sexual signals, and to do so safe from predators. This is particularly important in terrestrial birds, which have to allow for topographical irregularities and the risks of living on the ground. We show how houbara bustard males display from sites that offer the best viewsheds, and more importantly, maximize the number of visible females, increasing their chances of attracting potential mates.