Meeting Abstract

P3.146  Tuesday, Jan. 6  Frugal energy use by Hemprichs long-eared bats () Otonycteris hemprichii) during pregnancy and nursing KORINE, C; DANIEL, S; PINSHOW, B*; Ben-Gurion University of the Negev; Ben-Gurion University of the Negev; Ben-Gurion University of the Negev pinshow@bgu.ac.il

We hypothesized that the energy balance of breeding female Hemprich’s long-eared bats Otonycteris hemprichii bats is shaped by a trade-off between the requirements for embryo or pup growth, and the mothers own need to use torpor to save energy and water. We used indirect calorimetry to measure metabolic rates (MR) of pregnant and nursing bats over a range of ambient temperatures. Mass specific MR of euthermic bats decreased from 22.95 mWg^-1 to 5.04 mWg^-1 as ambient temperature increased from 15 C to 33 C, and was not different from that of non-reproductive female bats. We estimated daily energy expenditure (DEE), taking into account the costs of foraging and roosting in pregnant and nursing bats. DEE increased by 54%, from late pregnancy (54.74 kJday^-1) to peak lactation (84.23 kJday^-1). This increase was smaller than the 78% – 182% increase measured with doubly labeled water in other insectivorous bat species. The proportion of DEE invested in maternal care by mother bats was about 30%, in the range found in other insectivorous bat species (28% – 32%). Our data indicate that the increase in DEE of female O. hemprichii during reproduction is relatively small compared to other insectivorous bats, which may be advantageous in desert habitats.