Thermoregulation and Flight Activity Satyrine, Coenonympha Inornata (Lepidoptera: Satyridae)

The inornate ringlet butterfly, Coenonympha inornata, is highly constrained by temperature in its activity, and even on sunny days may spend a major portion of its time grounded. Thermoregulation in these lateral baskers can consume the major portion of their time; males alternate between basking and flying, and at 16°C spend 73% of their time basking and only 27% of their time flying. At high ambient temperatures (T a ), on the other hand, they spend most (>80%) of their time in flight. Active butterflies were followed for up to 52 min in the field to determine foraging behavior, mating success, and time investments for thermoregulation. Foraging was a minor component of their flight activity. Most of the flight activity was associated with mate—seeking. Thoracic temperatures were measured in the field on individuals tethered to thermocouples that permitted flight and basking behavior. Basking at low T a allowed the maintenance of higher thoracic temperatures than could be maintained in continuous flight, and the butterflies then adopted a sit—and—wait strategy in mate chasing. In contrast, at high T a they used a search strategy for mate seeking instead.