RT Journal Article
SR Electronic
T1 Experimental duration and predator satiation levels systematically affect functional response parameters
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 108886
DO 10.1101/108886
A1 Yuanheng Li
A1 Björn C. Rall
A1 Gregor Kalinkat
YR 2017
UL http://biorxiv.org/content/early/2017/03/04/108886.abstract
AB Empirical feeding studies where density-dependent consumption rates are fitted to functional response models are often used to parametrize the interaction strengths in models of population or food-web dynamics. However, the relationship between functional response parameter estimates from short-term feeding studies and real-world, long-term, trophic interaction strengths remains largely untested. In a critical first step to address this void, we tested for systematic effects of experimental duration and predator satiation on the estimation of functional response parameters, namely attack rate and handling time. Analyzing a large data set covering a wide range of predator taxonomies and body sizes we show that attack rates decrease with increasing experimental duration, and that handling times of starved predators are consistently shorter than those of satiated predators. Therefore, both the experimental duration and the predator satiation level have a strong and systematic impact on the predictions of population dynamics and food-web stability. Our study highlights potential pitfalls at the intersection of empirical and theoretical applications of functional responses. We conclude our study with some practical suggestions how these implications should be addressed in the future to improve predictive abilities and realism in models of predator-prey interactions.