Observation of movement and activity via radio-telemetry reveals diurnal behavior of the neotropical katydid Philophyllia Ingens (Orthoptera: Tettigoniidae)

Abstract

Detailed knowledge of species’ and individual behaviour is important for the understanding of ecological processes, but relevant data, particularly on small animals like insects are still widely lacking. Using newly available miniaturized technology, we radio-tracked movement and activity of ten male individuals of the Neotropical katydid Philophyllia ingens (Tettigonidae: Phaneropterinae) in its natural rainforest habitat during 3.1 ± 1.8 days. Although most katydids are assumed to be predominantly nocturnal our results revealed peaks of activity during the day, probably feeding and/or stridulating activity, while long distance movements of ≥ 100 m were only observed at night. Home range size was 1139 ± 555 m2. Onset, but not drop-off of activity was correlated with peaks in wind speed and temperature. In addition, we observed a daily concerted downward movement from the canopy that may be a behaviour to avoid predation, while the earlier upward movement might be connected with temperature and food availability.