Seasonal behavioral responses of an arid-zone passerine in a hot environment.

Autor: Pattinson NB; Centre of African Conservation Ecology, Department of Zoology, Nelson Mandela Metropolitan University, Port Elizabeth 6031, South Africa., Smit B; Centre of African Conservation Ecology, Department of Zoology, Nelson Mandela Metropolitan University, Port Elizabeth 6031, South Africa. Electronic address: B.Smit@ru.ac.za.
Jazyk: angličtina
Zdroj: Physiology & behavior [Physiol Behav] 2017 Oct 01; Vol. 179, pp. 268-275. Date of Electronic Publication: 2017 Jun 27.
DOI: 10.1016/j.physbeh.2017.06.018
Abstrakt: Many arid-zone animals have to forage under extremely hot conditions to maintain water and energy balance. The effect of high air temperatures (T air ) on the behavioral patterns of small endothermic animals-characterized by their high energy and water demands-will provide a valuable framework for understanding species vulnerability to climate warming. We determined the seasonal behavioral responses to changes in T air in a~10-g arid-zone passerine, the rufous-eared warbler (Malcorus pectoralis), in the Karoo semi-desert, South Africa. Rufous-eared warblers showed significant temperature-dependence in their behavior in summer, but not in winter. During summer, the warblers frequently experienced T air exceeding 40°C in the shade. For all observations <26°C compared to >36°C, the warblers showed reductions in preening (40% decrease), foraging effort (56% decrease), and foraging success (15% decrease), as well as a significant increase in time spent engaged in evaporative cooling behavior. Moreover, as T air increased the warblers shifted increasingly off the ground and out of the full sun, into microsites in the shade (131% increase) and in shrubs (23% increase). In this regard, behavior varied seasonally, with the time spent in the shade 23% higher, and foraging effort 28% higher, in summer compared to winter across a range of moderate T air (15-30°C). Our findings emphasize the link between behavior and temperature in small birds inhabiting hot, arid environments, as well as the importance of understanding these responses for predicting biologically meaningful responses (and hence, vulnerability) of arid-zone avian communities to climactic shifts.
(Copyright © 2017 Elsevier Inc. All rights reserved.)
Databáze: MEDLINE
Externí odkaz: