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Age and sex differences in numerical responses, dietary shifts, and total responses of a generalist predator to population dynamics of main prey.

ABSTRACT: Fluctuations in the abundance of main prey species might shape animal communities, by inducing numerical responses and dietary shifts in predators. Whether numerical responses and dietary shifts differ among individuals of different age and sex has so far gained little attention. These differences could affect how much predators consume main and alternative prey, thus causing variation in predation pressure on main and alternative prey species. We studied the effect of fluctuating main prey abundance (voles) in autumn on the age and sex composition of a food-hoarding population of Eurasian pygmy owls Glaucidium passerinum (327 individuals), and on the species composition of their food stores in western Finland during 2003-2017 (629 food stores). Numbers of yearlings (

SUBMITTER: Masoero G

PROVIDER: S-EPMC7058601 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Age and sex differences in numerical responses, dietary shifts, and total responses of a generalist predator to population dynamics of main prey.

Masoero Giulia G Laaksonen Toni T Morosinotto Chiara C Korpimäki Erkki E

Oecologia 20200201 3

Fluctuations in the abundance of main prey species might shape animal communities, by inducing numerical responses and dietary shifts in predators. Whether numerical responses and dietary shifts differ among individuals of different age and sex has so far gained little attention. These differences could affect how much predators consume main and alternative prey, thus causing variation in predation pressure on main and alternative prey species. We studied the effect of fluctuating main prey abun ...[more]

PMID: 32008080

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