The Effects of a Temperature-Determined Food-Supply on the Annual Activity Cycle of the Lesser Long-Eared Bat, Nyctophilus-Geoffroyi Leach, 1821 (Microchiroptera, Vespertilionidae)

Abstract

Tritiated-water turnover rates for captive Nyctophilus geoffroyi were highest at 1031.3 mL L-1 day-1 for lactating females in January 1985 and lowest at 82.5 mL L-1 day-1 for females receiving a temperature-determined food supply in July 1985. Daily rates of water turnover were generally higher for males than females, and for bats receiving ad libitum food than for those receiving a controlled food supply throughout winter, indicating that food availability affects torpor in N. geoffroyi. Pre-winter fat deposition was more efficient under conditions of a temperature-determined food supply, where activity, weight and fat-level fluctuations of captive N. geoffroyi closely resembled those known for free-ranging temperate-zone microchiropterans.