This dataset contains maternal reproductive output data, embryonic development data and offspring performance data for the Speckled Wood butterfly, Pararge aegeria. The data were collected from a laboratory experiment testing the hypothesis that repeat periods of intensive flight during female oviposition affects egg provisioning and reduces offspring performance when larval development occurs on drought stressed host plants. The experiment involved stimulating female butterflies to fly for 5 minutes for 3 periods during oviposition; removing eggs from 5 different days during oviposition to be monitored for hatching; and removing a larva on day of hatching to be reared on a drought stressed host plant. For each larva, development time from hatching to pupation, pupal mass and survival to eclose as an adult was recorded. On eclosion, each offspring adult was sexed and the thorax weighed. The overall aim of this experimental work was to explore one of the potential mechanisms for the impact of drought and habitat fragmentation on biodiversity. Full details about this nonGeographicDataset can be found at https://doi.org/10.5285/82233733-237a-4fea-a5c1-88c734752279