impact of climate and cyclic food abundance on the timing of breeding and brood size in four boreal owl species

• Published in: Oecologia Vol. 165; no. 2; pp. 349 - 355
• Main Authors: Lehikoinen, Aleksi, Ranta, Esa, Pietiäinen, Hannu, Byholm, Patrik, Saurola, Pertti, Valkama, Jari, Huitu, Otso, Henttonen, Heikki, Korpimäki, Erkki
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01-02-2011; Springer; Springer-Verlag; Springer Nature B.V
• Subjects: Abundance; Aegolius funereus; Animal and plant ecology; Animal breeding; Animal, plant and microbial ecology; Animals; Animals, Newborn; Aviculture; Behavior; Biological and medical sciences; Biomedical and Life Sciences; Birds of prey; Breeding; Breeding seasons; Breeding success; Capital and income breeding; Climate; Climate change; Climate models; Climatic changes; Climatic conditions; Ecology; Food availability; Food Chain; Fundamental and applied biological sciences. Psychology; General aspects; Glaucidium passerinum; Global Warming; Hatching; Hydrology/Water Resources; Life Sciences; Mammalia; Owls; Plant Sciences; POPULATION ECOLOGY; Population ecology - Original Paper; Predators; Prey; Reproduction; Reproductive success; Rodent abundance; Snow; Snow depth; Spring; Strigiformes - classification; Strigiformes - physiology; Strix aluco; Strix uralensis; Temperature; Temperature effects; Time Factors; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; Voles; Weather; Weather conditions; Russia, Ural Mts; Reproduction; Global warming; Capital and income breeding; Weather conditions; Rodent abundance; Climate; Rodentia; Clutch size; Raptor; Aegolius funereus; Feeding; Weather; Vertebrata; Mammalia; Global waring; Timing; Aves
• ISSN: 0029-8549; 1432-1939
• DOI: 10.1007/s00442-010-1730-1

The ongoing climate change has improved our understanding of how climate affects the reproduction of animals. However, the interaction between food availability and climate on breeding has rarely been examined. While it has been shown that breeding of boreal birds of prey is first and foremost determined by prey abundance, little information exists on how climatic conditions influence this relationship. We studied the joint effects of main prey abundance and ambient weather on timing of breeding and reproductive success of two smaller (pygmy owl Glaucidium passerinum and Tengmalm's owl Aegolius funereus) and two larger (tawny owl Strix aluco and Ural owl Strix uralensis) avian predator species using long-term nation-wide datasets during 1973-2004. We found no temporal trend either in vole abundance or in hatching date and brood size of any studied owl species. In the larger species, increasing late winter or early spring temperature advanced breeding at least as much as did high autumn abundance of prey (voles). Furthermore, increasing snow depth delayed breeding of the largest species (Ural owl), presumably by reducing the availability of voles. Brood size was strongly determined by spring vole abundance in all four owl species. These results show that climate directly affects the breeding performance of vole-eating boreal avian predators much more than previously thought. According to earlier studies, small-sized species should advance their breeding more than larger species in response to increasing temperature. However, we found an opposite pattern, with larger species being more sensitive to temperature. We argue that this pattern is caused by a difference in the breeding tactics of larger mostly capital breeding and smaller mostly income breeding owl species.