Linking short-term behavior and personalities to feeding and mating rates in female water striders

In systems of strong sexual conflict, male harassment can constrain female feeding, which can limit fecundity. Female responses to harassment can depend on the social context or differ between individuals, and could be based on social or intrinsic behavioral cues at different spatio-temporal scales. Using experimental groupings of stream water striders (Aquarius remigis), we examined individual behavioral differences and effects of sex ratio on 4 aspects of female behavior: 1) habitat use and 2) activity, which lead to differences in 3) feeding rates and 4) mating rates. We compared effects of the immediate social environment, immediate female habitat use and activity, and consistent female behavioral tendencies (personalities) on feeding and mating probabilities, and asked if population sex ratio affected the relationships among these behaviors. We found that individual females did differ significantly in all 4 behaviors. Population sex ratio strongly influenced average female habitat use, feeding, and mating behaviors, and female feeding and mating behaviors were predicted by a combination of moment-to-moment female behavioral state, moment-to-moment social factors, and consistent individual female behavioral differences. Furthermore, habitat use tendencies correlated significantly with activity tendencies, and habitat use and activity tendencies predicted mating probabilities, but not feeding probabilities. Our study elucidates the specific individual-level behavioral mechanisms that lead to observed population-level patterns and emphasizes the benefits of studying behavior at multiple spatial and temporal scales.