Transient recovery dynamics of a predator\u2013prey system under press and pulse disturbances

Canan Karakoç,Karin Johst,Antonis Chatzinotas,Hauke Harms,Alexander Singer

doi:10.1186/s12898-017-0123-2

Abstract

BackgroundSpecies recovery after disturbances depends on the strength and duration of disturbance, on the species traits and on the biotic interactions with other species. In order to understand these complex relationships, it is essential to understand mechanistically the transient dynamics of interacting species during and after disturbances. We combined microcosm experiments with simulation modelling and studied the transient recovery dynamics of a simple microbial food web under pulse and press disturbances and under different predator couplings to an alternative resource.ResultsOur results reveal that although the disturbances affected predator and prey populations by the same mortality, predator populations suffered for a longer time. The resulting diminished predation stress caused a temporary phase of high prey population sizes (i.e. prey release) during and even after disturbances. Increasing duration and strength of disturbances significantly slowed down the recovery time of the predator prolonging the phase of prey release. However, the additional coupling of the predator to an alternative resource allowed the predator to recover faster after the disturbances thus shortening the phase of prey release.ConclusionsOur findings are not limited to the studied system and can be used to understand the dynamic response and recovery potential of many natural predator–prey or host–pathogen systems. They can be applied, for instance, in epidemiological and conservational contexts to regulate prey release or to avoid extinction risk of the top trophic levels under different types of disturbances.

Highlights

Species recovery after disturbances depends on the strength and duration of disturbance, on the species traits and on the biotic interactions with other species
We found that disturbance strength and duration were decisive for the different transient recovery dynamics of the two trophic levels
At the end of the press disturbance, this high equilibrium population size remained for two more days and turned back to the pre-disturbance size which was reached after full predator recovery on day 33

Summary

Introduction

Species recovery after disturbances depends on the strength and duration of disturbance, on the species traits and on the biotic interactions with other species. We combined microcosm experiments with simulation modelling and studied the transient recovery dynamics of a simple microbial food web under pulse and press disturbances and under different predator couplings to an alternative resource. The trophic status in food webs plays a major role for the species response to disturbances [11,12,13]. Traits such as large body size, slow growth rate and Karakoç et al BMC Ecol (2017) 17:13 low population size make top predators more vulnerable than other trophic levels. In a microcosm study, increasing temperature led to increasing invasion success of a bacterial prey species due to the increased prey release from protozoan predation stress [17]

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Results

Discussion

Conclusion