Many insects undertake long-range seasonal migrations to exploit temporary breeding sites hundreds or thousands of kilometers apart, but the behavioral adaptations that facilitate these movements remain largely unknown. Using entomological radar, we showed that the ability to select seasonally favorable, high-altitude winds is widespread in large day- and night-flying migrants and that insects adopt optimal flight headings that partially correct for crosswind drift, thus maximizing distances traveled. Trajectory analyses show that these behaviors increase migration distances by 40% and decrease the degree of drift from seasonally optimal directions. These flight behaviors match the sophistication of those seen in migrant birds and help explain how high-flying insects migrate successfully between seasonal habitats.

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Many ant species produce winged reproductive males and females that embark on mating flights. Previous research has shown substantial synchrony in flights between colonies and that weather influences phenology but these studies have been limited by sample size and spatiotemporal scale. Using citizen science, we gathered the largest ever dataset (> 13 000 observations) on the location and timing of winged ant sightings over a three‐year period across a broad spatial scale (the United Kingdom). In total, 88.5% of winged ants sampled were Lasius niger. Observations occurred from June to September with 97% occurring in July/August but exact temporal patterns differed substantially between years. As expected, observations within each year showed a small but significant northward/westward trend as summer progressed. However, the predicted spatiotemporal synchrony was far less apparent; observations were not significantly spatially clustered at national, regional or local scales. Nests in urban (vs rural) areas and those associated with heat‐retaining structures produced winged ants earlier. Local weather conditions rather than broad geographical or seasonal factors were shown to be critical in the timing of winged ant activity, presumably to optimize mate finding and to minimize energy consumption and predation. Temperature and wind speed, but not barometric pressure, were significant predictors of observations (positively and negatively, respectively); winged ants were only observed at temperatures > 13°C and wind‐speeds < 6.3 m–1. All days with a mean daily temperature > 25°C had observations. Intriguingly, changes in temperature and wind speed from the day before flight peaks were also significant. We conclude that: 1) spatiotemporal synchrony in flights is lower than previously thought for L. niger, 2) local temperature and wind are key predictors of flight phenology; and 3) ants appear able to determine, at least in a limited way, if weather is improving or deteriorating and adjust their behaviour accordingly.

The seasonal appearance of Tegenaria and Eratigena (the best known of the UK genera termed "house spiders") results in considerable public and media interest. Here, we present the largest dataset ever gathered on the occurrence of house spiders anywhere in the world. We collected almost 10,000 records from different locations within the UK (amounting to ca. 250X more locations and 25X more records than any previous study) over a 6-month period. Using this dataset, which contained details of sighting dates, times, location within UK, location within the home, location within rooms and sex, we were able to investigate a number of aspects of house spider ecology. Eighty-two percent of records were males, supporting previous studies that showed house spider surges in autumn are predominantly males seeking mates. Sightings peaked in mid-September with a significant northwest progression 2 across the UK as autumn progressed. Daily activity peaked at 19:35hrs and spiders were seen more-orless uniformly throughout different rooms and we discuss why this is more likely to be because of spider ecology than human behaviour. Within rooms, there was a sex-based difference in ecology with females more common on ceilings and doors/windows and males more common on walls, possibly because of sex-specific differences in mobility.

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