The effect of reproductive condition on thermoregulation in a viviparous gecko from a cool climate

(1) Hoplodactylus maculatus, is a nocturnal, viviparous gecko that inhabits a cool-temperate region. (2) To determine if pregnant females expend more effort thermoregulating than non-pregnant females or males, we compared field body temperature (T-b) with microhabitat thermal maxima (T-top), thermal minima (T-bot) and selected temperature (T-sel) among males, non-pregnant females and pregnant females. (3) An index of hermoregulatory effectiveness that incorporated diurnal variation in T-sel was used to compare among reproductive conditions. (4) Relationships between T-b, T-top and T-bot varied between reproductive conditions and seasons, suggesting complex diurnal thermoregulatory strategies in this nocturnal species. (5) Pregnant females achieved higher indices of thermoregulatory effort than males in both seasons, with the highest value in late spring and a slightly lower index similar to that of non-pregnant females in summer. (C) 2002 Elsevier Science Ltd. All rights reserved.