Body size, not species identity, drives body heating in alpine Erebia butterflies. (April 2023)

• Record Type: Journal Article
• Authors: Kleckova, Irena; Okrouhlík, Jan; Svozil, Tomas; Matos-Maraví, Pável; Klecka, Jan
• Is Part Of: Journal of thermal biology. Volume 113(2023)
• Publication Date: 2023-04
• Subjects: Alpine species -- Ecophysiology -- Habitat use -- Lepidoptera -- Thermal camera; Thermobiology -- Periodicals; Temperature -- Periodicals; Biology -- Periodicals; Thermobiologie -- Périodiques; Thermobiology; Periodicals; 571.46
• DOI: 10.1016/j.jtherbio.2023.103502
• Languages: English
• ISSNs: 0306-4565

Abstract

Abstract: Efficient thermoregulation is crucial for animals living under fluctuating climatic and weather conditions . We studied the body heating of six butterfly species of the genus Erebia (Lepidoptera: Nymphalidae) that co-occur in the European Alps. We tested whether butterfly physical characteristics (body size, wing loading) are responsible for the inter-specific differences in body temperatures recorded previously under natural conditions. We used a thermal camera to measure body heating of wild butterfly individuals in a laboratory experiment with artificial light and heating sources. We revealed that physical characteristics had a small effect on explaining inter-specific differences in mean body temperatures recorded in the field. Our results show that larger butterflies, with higher weight and wing loading, heated up more slowly but reached the same asymptotic body temperature as smaller butterflies. Altogether, our results suggest that differences in body temperatures among Erebia species observed in the field might be caused mainly by species-specific microhabitat use and point towards an important role of active behavioural thermoregulation in adult butterflies. We speculate that microclimate heterogeneity in mountain habitats facilitates behavioural thermoregulation of adults. Similarly, microclimate structuring might also increase survival of less mobile butterfly life stages, i.e., eggs, larvae and pupae. Thus, landscape heterogeneity in management practices may facilitate long term survival of montane invertebrates under increased anthropogenic pressures. Highlights: Alpine Erebia butterfly species differ in body temperature under natural conditions. We tested whether physical characteristics drive body heating. We found that smaller species heated up more quickly than large ones. Physical characteristics had a small effect on body heating in lab experiments. Body temperature is driven by microhabitat choice more than by physical traits.