Inter-population variation and phenotypic plasticity in kairomone use by a poly-specialist spider-eating predator

Abstract

Previous research on Cyrba algerina (Araneae, Salticidae) has shown this jumping spider expresses predatory specialisation with respect to spiders as prey as well as inter-population variation in responsiveness to prey-spider odour. However, this earlier research pertained to a single prey species (Oecobius machadoi) and only field-collected C. algerina individuals were tested. Here we extend the previous research by using laboratory-reared, as well as field-collected, individuals of C. algerina and also by using another prey-spider species, Zelotes thorelli, as well as O. machadoi. Two localities in Portugal are considered, Sintra where C. algerina and both prey species are abundant and Tavira where C. algerina is present but neither prey species has been found. In olfactometer experiments, field-collected C. algerina individuals from Sintra, but not Tavira, were attracted to the odour of both prey species. Next, we tested the response of laboratory-reared Sintra C. algerina individuals that had been maintained with no prior experience with the odour of either prey species. We found no evidence of laboratory-reared individuals being attracted to the odour of either prey species in the olfactometer. These findings suggest that prior experience mediates responsiveness of C. algerina to the odour of local prey.