Behavioural mechanisms underlying parasite-mediated competition for refuges in a coral reef fish

Abstract Parasites have been increasingly recognized as participants in indirect ecological interactions, including those mediated by parasite-induced changes to host behaviour (trait-mediated indirect interactions or TMIIs). In most documented examples, host behaviours altered by parasites increase susceptibility to predation because the predator is also a host (host-manipulation). Here, we test for a TMII in which a parasitic copepod modifies the predator-prey interaction between a small goby host and several larger predatory fish. Gobies compete for crevices in the reef to avoid predation and goby mortality increases more rapidly with increasing refuge shortage for parasitized gobies than for those free of parasites. We found interactive effects of refuge shortage and parasitism on two behaviours we predicted might be associated with parasite-mediated competition for refuges. First, as refuge-shortage increases, the rate of aggression among gobies increases and parasitism intensifies this interaction. Second, goby proximity to refuges increases as refuges become scarce, but parasitism nullifies this increase. In combination, these parasite-induced changes in behaviour may explain why parasitized gobies are poor competitors for refuges. Because the parasite is not trophically transmitted via host manipulation, these altered behaviours in parasitized gobies are likely coincidental to infection.

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Predator-Prey Interactions

Ecology ◽

10.1093/obo/9780199830060-0100 ◽

2013 ◽

Author(s):

Timothy C. Roth II ◽

Maria Thaker

Keyword(s):

Population Dynamics ◽

Natural World ◽

Ecological Interactions ◽

Community Interactions ◽

Predator Prey ◽

Individual Level ◽

Prey Interaction ◽

Definition Of ◽

The Individual ◽

Phenotypic Responses

All animals are either predators or prey and, in most cases, they are both. The interactions involved in attempting to eat and avoid being eaten have strong and wide-reaching influences across all facets of ecology, from individual phenotypic responses and population dynamics, to community interactions, and even to how we attempt to manage and conserve the natural world. As in many subfields of ecology, the science behind predator-prey investigations has been driven by theory, including important advances in generating and testing predictions. This article highlights the breadth of influence that predator-prey interactions have on ecology. The sections that follow address the effects of predator-prey interactions, such as those at the individual level, expressed through behavior, morphology, physiology, and life history, as well as their effects on population dynamics and community composition. At the individual level, the predator-prey interaction will be arranged in two perspectives: those of the predator and those of the prey. The article also considers the less typical and more integrative aspects of predator-prey interactions, such as their physiological and neurological mechanisms and their relevance for questions associated with conservation. In addition, this article will consider the validity of including parasitism and herbivory within the broad definition of predation. A great deal of debate is ongoing as to whether these two ecological interactions possess similar enough qualities with predation to be characterized as one phenomenon. Those sections of this article will cover this debate and provide the reader with resources with which to consider this question.

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Role reversal in a predator–prey interaction

Royal Society Open Science ◽

10.1098/rsos.140186 ◽

2014 ◽

Vol 1 (2) ◽

pp. 140186 ◽

Cited By ~ 4

Author(s):

Faustino Sánchez-Garduño ◽

Pedro Miramontes ◽

Tatiana T Marquez-Lago

Keyword(s):

Population Ecology ◽

Ecological Niche ◽

Classical System ◽

Role Reversal ◽

Ecological Interactions ◽

Predator Prey ◽

Field Evidence ◽

Niche Shifts ◽

Prey Interaction ◽

Spatio Temporal

Predator–prey relationships are one of the most studied interactions in population ecology. However, little attention has been paid to the possibility of role exchange between species, despite firm field evidence of such phenomena in nature. In this paper, we build a mathematical model capable of reproducing the main phenomenological features of role reversal in a classical system and present results for both the temporal and spatio-temporal cases. We show that, depending on the choice of parameters, our role-reversal dynamical system exhibits excitable-like behaviour, generating waves of species' concentrations that propagate through space. Our findings fill a long-standing gap in modelling ecological interactions and can be applicable to better understanding ecological niche shifts and planning of sustainable ecosystems.

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