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Consistent temperature dependence of functional response parameters and their use in predicting population abundance.

ABSTRACT: Global warming is one of the greatest threats to the persistence of populations: increased metabolic demands should strengthen pairwise species interactions, which could destabilize food webs at the higher organizational levels. Quantifying the temperature dependence of consumer-resource interactions is thus essential for predicting ecological responses to warming. We explored feeding interactions between different predator-prey pairs in controlled-temperature chambers and in a system of naturally heated streams. We found consistent temperature dependence of attack rates across experimental settings, though the magnitude and activation energy of attack rate were specific to each predator, which varied in mobility and foraging mode. We used these parameters along with metabolic rate measurements to estimate energetic efficiency and population abundance with warming. Energetic efficiency accurately estimated field abundance of a mobile predator that struggled to meet its metabolic demands, but was a poor predictor for a sedentary predator that operated well below its energetic limits. Temperature effects on population abundance may thus be strongly dependent on whether organisms are regulated by their own energy intake or interspecific interactions. Given the widespread use of functional response parameters in ecological modelling, reconciling outcomes from laboratory and field studies increases the confidence and precision with which we can predict warming impacts on natural systems.

SUBMITTER: Archer LC

PROVIDER: S-EPMC6899737 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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Consistent temperature dependence of functional response parameters and their use in predicting population abundance.

Archer Louise C LC Sohlström Esra H EH Gallo Bruno B Jochum Malte M Woodward Guy G Kordas Rebecca L RL Rall Björn C BC O'Gorman Eoin J EJ

The Journal of animal ecology 20190809 11

Global warming is one of the greatest threats to the persistence of populations: increased metabolic demands should strengthen pairwise species interactions, which could destabilize food webs at the higher organizational levels. Quantifying the temperature dependence of consumer-resource interactions is thus essential for predicting ecological responses to warming. We explored feeding interactions between different predator-prey pairs in controlled-temperature chambers and in a system of natural ...[more]

PMID: 31283002

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Consistent temperature dependence of functional response parameters and their use in predicting population abundance.

Publications

Consistent temperature dependence of functional response parameters and their use in predicting population abundance.

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