mosquito consumption by insectivorous bats: does size matter?insectivorous bats have often been touted as biological control for mosquito populations. however, mosquitoes generally represent only a small proportion of bat diet. given the small size of mosquitoes, restrictions imposed on prey detectability by low frequency echolocation, and variable field metabolic rates (fmr), mosquitoes may not be available to or profitable for all bats. this study investigated whether consumption of mosquitoes was influenced by bat size, which is negatively correlated w ...201324130851
peak density and distribution of ganglion cells in the retinae of microchiropteran bats: implications for visual acuity.we have estimated the total number, distribution and peak density of retinal ganglion cells (rgcs) in retinal wholemounts of several species of microchiropteran (echolocating) bats. the estimates are based on counts of nissl-stained, presumed rgcs. the total number of presumed rgcs varies among the species: from about 4,500 in rhinolophus rouxi to about 120,000 in macroderma gigas. in addition, in two species (nyctophilus gouldi and m. gigas), the estimates are based on counts of positively iden ...19883191381
who's for dinner? high-throughput sequencing reveals bat dietary differentiation in a biodiversity hotspot where prey taxonomy is largely undescribed.effective management and conservation of biodiversity requires understanding of predator-prey relationships to ensure the continued existence of both predator and prey populations. gathering dietary data from predatory species, such as insectivorous bats, often presents logistical challenges, further exacerbated in biodiversity hot spots because prey items are highly speciose, yet their taxonomy is largely undescribed. we used high-throughput sequencing (hts) and bioinformatic analyses to phylog ...201424118181
acoustical and neural aspects of hearing in the australian gleaning bats, macroderma gigas and nyctophilus gouldi.1. the maximum acoustic gain of the external ear in macroderma gigas was found to be 25-30 db between 5-8 khz and in nyctophilus gouldi it reached 15-23 db between 7-22 khz. pinna gain reached a peak of 16 db near 4.5-6 khz in m. gigas and 12-17 db between 7-12 khz in n. gouldi, with average gain of 6-10 db up to 100 khz. pinna gain curves resemble that of a finite conical horn, including resonance. 2. the directional properties of the external ear in both species result from sound diffraction a ...19883373455
black or white? physiological implications of roost colour and choice in a microbat.although roost choice in bats has been studied previously, little is known about how opposing roost colours affect the expression of torpor quantitatively. we quantified roost selection and thermoregulation in a captive australian insectivorous bat, nyctophilus gouldi (n=12) in winter when roosting in black and white coloured boxes using temperature-telemetry. we quantified how roost choice influences torpor expression when food was provided ad libitum or restricted in bats housed together in an ...201627503729
measuring subcutaneous temperature and differential rates of rewarming from hibernation and daily torpor in two species of bats.prolonged and remote measurement of body temperature (tb) in undisturbed small hibernators was not possible in the past because of technological limitations. although passive integrated transponders (pits) have been used previously to measure subcutaneous temperature (tsub) during daily torpor in a small marsupial, no study has attempted to use these devices at tbs below 10°c. therefore, we investigated whether subcutaneous interscapular pits can be used as a viable tool for measuring tb in a sm ...201526300411
passive rewarming from torpor in hibernating bats: minimizing metabolic costs and cardiac demands.endothermic arousal from torpor is an energetically costly process and imposes enormous demands on the cardiovascular system, particularly during early stage arousal from low body temperature (tb). to minimize these costs many bats and other heterothermic endotherms rewarm passively from torpor using solar radiation or fluctuating ambient temperature (ta). because the heart plays a critical role in the arousal process in terms of blood distribution and as a source of heat production, it is desir ...201525411363
heart rate as a predictor of metabolic rate in heterothermic bats.while heart rate (fh) has been used as an indicator of energy expenditure, quantitative data showing the relationship between these variables are only available for normothermic animals. to determine whether fh also predicts oxygen consumption ( ) during torpor, we simultaneously measured , fh and subcutaneous body temperature (tsub) of a hibernator, gould's long-eared bats (nyctophilus gouldi, 9 g, n=18), at ambient temperatures (ta) between 0 and 25°c. at rest, fh of normothermic resting bats ...201424436390
heterothermy, torpor, respiratory gas exchange, water balance and the effect of feeding in gould's long-eared bat nyctophilus gouldi.the effects of temperature and nutritional status on the metabolic rate of nyctophilus gouldi were examined. bats fed marked meals first defecated approximately 1.34 h after feeding and were calculated to have a mean retention time of 5.38 +/- 0.57 h but to be truly post-absorptive after 9 h. over the temperature range 1-35 degrees c, the metabolic rate (vo2) and body temperature (tb) of fasted bats were extremely labile. below 30 degrees c, the bats all entered torpor and between 10 and 15 degr ...19947852907
no effect of season on the electrocardiogram of long-eared bats (nyctophilus gouldi) during torpor.heterothermic animals regularly undergo profound alterations of cardiac function associated with torpor. these animals have specialised tissues capable of withstanding fluctuations in body temperature‚ÄČ>‚ÄČ30 °c without adverse effects. in particular, the hearts of heterotherms are able to resist fibrillation and discontinuity of the cardiac conduction system common in homeotherms during hypothermia. to investigate the patterns of cardiac conduction in small insectivorous bats which enter torpor ye ...201829623413
interspecific differences and commonalities in maternity roosting by tree cavity-roosting bats over a maternity season in a timber production landscape.understanding maternity roost requirements is fundamental to guide timber production forest management given such roosts are vital to sustain bat populations. we tracked lactating females of three tree cavity-roosting species: gould's long-eared bat (nyctophilus gouldi) (n = 7), eastern broad-nosed bat (scotorepens orion) (n = 6) and little forest bat (vespadelus vulturnus) (n = 25), over five weeks in young (predominately <5 years old) forest regenerating from heavy timber harvest in southeast ...201829543883
can bats sense smoke during deep torpor?while torpor is a beneficial energy-saving strategy, it may incur costs if an animal is unable to respond appropriately to external stimuli, which is particularly true when it is necessary to escape from threats such as fire. we aimed to determine whether torpid bats, which are potentially threatened because they must fly to escape, can sense smoke and whether respiration rate (rr), heart rate (hr) and reaction time of torpid bats prior to and following smoke introduction is temperature-dependen ...201829253491
Displaying items 1 - 12 of 12