Sublethal effects of kleptoparasitism on experimental social spider colonies

Abstract A defining feature of parasitism is the harm parasites cause to their host via a reduction in lifetime reproductive success. Harm, also referred as “virulence,” may involve mortality or sublethal effects, such decreased body condition protracted development immature individuals. We considered system where colonies social spider Anelosimus eximius serve hosts confamilial kleptoparasitic spiders that steal food resources. In laboratory experiment with parasitized and non‐parasitized colonies, we tested whether this host–parasite interaction meets criterium individuals colonies. assessed survival measured scaled mass indices (SMI) before after experimental period. Linear mixed effects models demonstrated exposed kleptoparasites had lower SMI values at end compared controls, but found no effect kleptoparasitism on treatment control groups. conclude meet be parasitic provide first empirical measure virulence for study system.