The Meaning of Jolts by Fish Clients of Cleaning Gobies

Abstract

Cooperative interactions offer the inherent possibility of cheating by each of the interacting partners. A key challenge to behavioural observers is to recognize these conflicts, and find means to measure reliably cheating in natural interactions. Cleanerfish Labroides dimidiatus cheat by taking scales and mucus from their fish clients and such dishonest cleaning has been previously recognized in the form of whole‐body jolts by clients in response to cleaner mouth contact. In this study, we test whether jolts may be a general client response to cheating by cleaners. We experimentally varied the ectoparasite loads of yellowtail damselfish (Microspathodon chrysurus), a common client of the cleaning goby Elacantinus evelynae, and compared the rates of jolts on parasitized and deparasitized clients. As predicted if jolts represent cleaner cheating, deparasitized clients jolted more often than parasitized clients, and overall jolt rates increased over time as client parasite load was presumably reduced by cleaning activity. Yellowtail damselfish in the wild jolted significantly less frequently than those in captivity, which is consistent with a loss of ectoparasites during capture. Our results suggest that jolts by clients of cleaning gobies are not related to the removal of ectoparasites. Client jolts may therefore be a generally accurate measure of cheating by cleanerfish.

Cortisol mediates cleaner wrasse switch from cooperation to cheating and tactical deception

“…Here we aimed to discover the potential role of changes in cortisol levels and the ability of cortisol signaling pathways to operate, on the social decision-making process of the cleaner wrasse. We conducted our study in natural conditions to determine whether exogenous administration of GCs (cortisol and the GC receptor antagonist mifepristone RU486) would produce variations in their degree of cooperation (tactile stimulation and cheating, the latter measured as client "jolts" in response to a feeding bite; Bshary and Grutter, 2002;Soares et al, 2008) when dealing with interspecific…”

“…eating mucus (Bshary and Grutter, 2002;Soares et al, 2008). Data were analysed using non-parametric tests because the assumptions for parametric testing were not met.…”

Crime and punishment in a roaming cleanerfish

“…Jolts are apparently painful reactions by clients to a cleanerfish bite. They have previously been shown to be unrelated to the removal of ectoparasites and are considered to be indicators of dishonest biting by cleaners (Bshary & Grutter 2002a;Soares et al 2008). At the end of each focal observation period, the maximum distance travelled by the cleaner (estimated visually) during the observation was noted, and used as a proxy for home range size.…”

Reproductive dependence of a branchiobdellidan annelid on its crayfish host: confirmation of a mutualism

“…Far from being benign, mutualisms are actually reciprocal exploitations in which the degree of exploitation results in beneficial outcomes for each partner (Herre et al, 1999). Overexploitation can destabilize these interactions and is prevented by various control mechanisms (Pellmyr & Huth, 1994;Soares et al, 2008;Farrell et al, 2014). In order to determine if an association is a mutualism it is critical to determine how each partner benefits and to verify the dependence of the partners on one another.…”