Phenology, Mating Behaviour, and Ecology of a Wild New Zealand Nurseryweb Spider ( Dolomedes minor )

Population dynamics are key to the understanding of mating systems, and in particular, sex ratios provide an insight into the evolutionary pressures governing a mating system. Variation in sex ratios can influence mate competition, parental investment strategies, and ultimately shape mating rates and the reproductive success of individuals within a population. Dolomedes (Dolomedidae) fishing spiders are frequent subjects in studies of mating behaviour and mating systems, although little is known about the mating behaviour of Dolomedes in Aotearoa New Zealand. In this study, we observed the dynamics and behaviours of a wild population of Dolomedes minor nurseryweb spiders for over 2 years. Observations were taken approximately fortnightly, with the sex and life stage of all individuals encountered recorded, as well as observations made of nurseryweb construction and other behaviour. We found no evidence of male‐biased sex ratios and protandry, instead observing an approximately even sex ratio. Timing of nurseryweb construction by females was observed in mid–late November and continued to April. The majority of food items identified were Diptera, exclusively in the Tipuloidea group. Several observations of mating behaviour were made, including a male attempting ‘soft‐mating’ with a female, a male attempting a ‘normal’ copulation with a female before fleeing at speed and a pair of males aggressively interacting in the presence of a female. The relative importance of each of these behaviours in the mating system of D. minor would make excellent material for future study.