Avian and rodent responses to the olfactory landscape in a Mediterranean cavity community
Animals rely on cues informing about future predation risk when selecting habitats to breed in. Olfactory information may play a fundamental role in the assessment of predation threats, because predators produce characteristic body odours, but the role of odours in habitat selection has seldom been considered. Here, we test whether fear of predation induced by odour cues may affect the settlement pattern of a Mediterranean cavity-dependent community of rodents and non-excavator hole-nesting birds. To test this hypothesis, we experimentally manipulated the perception of predation risk on a scale of patch by applying either odours of a carnivore predator (risky odour treatment), lemon essence (non-risky odour treatment) and a control non-odorous treatment and studied bird and rodent settlement patterns. Nest-box occupation probability differed across treatments so that species in the community settled in more numbers in control than in non-risky and than in risky odour-treated nest boxes. Concerning settlement patterns, control nest boxes were occupied more rapidly than nest boxes with odour information. Birds and rodents settled earlier in control than in risky odour-treated nest boxes, but their settlement pattern did not significantly vary between risky odour and non-risky odour-treated nest boxes. Our findings demonstrate that olfactory cues may be used to assess habitat quality by settling species in this community, but we cannot pinpoint the exact mechanism that has given rise to the pattern of preference by nest boxes.
KeywordsBirds Cavity community Fear ecology Habitat selection Olfactory landscape Predation risk
We thank Juan Rodríguez-Ruiz for help during data collection and Robert L. Thomson, Jere Tolvanen and Liana Zanette for their very useful comments on previous drafts of the manuscript. This study was funded by the Spanish Ministries of Education and Science/FEDER and of Economy and Competitiveness, respectively, through the projects CGL2011-27561/BOS, CGL2014-56769-P to JMA and DP and by the Government of Extremadura through the contract TA13002 to DP. MEG was supported by the Spanish Ministry of Economy and Competitiveness (grant number BES-2012-051898).
Author contribution statement
JMA and DP conceived, designed and coordinated the study. MEG participated in data analysis and in the design of the study and collected field data together with JMA and DP. JMA carried out the statistical analyses and drafted the manuscript. All authors gave final approval for publication.
- Aviles JM, Parejo D (2018) Origen y adecuación de cavidades para aves no-excavadoras en los encinares del Conejo. Efectos de la instalación de cajas nido. In: Navarro FBG (ed) Finca experimental Cortijos del Conejo y Albarrán y Cortijo Becerra (Guadix, Granada): Área de referencia en investigación del medio natural en el SE semiárido ibérico. University of Granada, GranadaGoogle Scholar
- Caro T (2005) Antipredator defenses in birds and mammals. University of Chicago Press, ChicagoGoogle Scholar
- Dhondt, A. A. 2012. Interspecific competition in birds. Oxford University PressGoogle Scholar
- Elton CS (2001) Animal ecology. University of Chicago Press, ChicagoGoogle Scholar