Investigation of Gray-Headed Flying Foxes (Pteropus poliocephalus) (Megachiroptera: Pteropodidae) and Mosquitoes in the Ecology of Ross River Virus in Australia

A colony site occupied by grey-headed flying-foxes (Pteropus poliocephalus) from October to May on the central coast of N.S.W. was monitored over a 48 month period (1986-1990). Faecal and spat-out material was collected for microscopic determination of contents. Comparison of food items in the droppings with the array of possible food sources present in the vicinity of the colony at the same time showed a marked preference for certain foods, in particular blossoms of the family Myrtaceae and of the genus Banksia. Cultivated orchard fruits were not a preferred food and were only taken at times when preferred food items were scarce.

Download Full-text

Daytime behaviour of the grey-headed flying fox Pteropus poliocephalus Temminck (Pteropodidae: Megachiroptera) at an autumn/winter roost.

Australian Mammalogy ◽

10.1071/am06002 ◽

2006 ◽

Vol 28 (1) ◽

pp. 7 ◽

Cited By ~ 6

Author(s):

K. A. Connell ◽

U. Munro ◽

F. R. Torpy

Keyword(s):

Management Strategies ◽

Reproductive Period ◽

Urban Environments ◽

Flying Foxes ◽

Fruit Bat ◽

Open Forest ◽

Pteropus Poliocephalus ◽

Baseline Information ◽

Daytime Behaviour ◽

Flying Fox

The grey-headed flying fox (Pteropus poliocephalus Temminck) is a threatened large fruit bat endemic to Australia. It roosts in large colonies in rainforest patches, mangroves, open forest, riparian woodland and, as native habitat is reduced, increasingly in vegetation within urban environments. The general biology, ecology and behaviour of this bat remain largely unknown, which makes it difficult to effectively monitor, protect and manage this species. The current study provides baseline information on the daytime behaviour of P. poliocephalus in an autumn/winter roost in urban Sydney, Australia, between April and August 2003. The most common daytime behaviours expressed by the flying foxes were sleeping (most common), grooming, mating/courtship, and wing spreading (least common). Behaviours differed significantly between times of day and seasons (autumn and winter). Active behaviours (i.e., grooming, mating/courtship, wing spreading) occurred mainly in the morning, while sleeping predominated in the afternoon. Mating/courtship and wing spreading were significantly higher in April (reproductive period) than in winter (non-reproductive period). Grooming was the only behaviour that showed no significant variation between sample periods. These results provide important baseline data for future comparative studies on the behaviours of flying foxes from urban and ?natural? camps, and the development of management strategies for this species.

Download Full-text

Testosterone is associated with harem maintenance ability in free-ranging grey-headed flying-foxes, Pteropus poliocephalus

Biology Letters ◽

10.1098/rsbl.2009.0563 ◽

2009 ◽

Vol 5 (6) ◽

pp. 758-761 ◽

Cited By ~ 16

Author(s):

Stefan M. Klose ◽

Justin A. Welbergen ◽

Elisabeth K. V. Kalko

Keyword(s):

Plasma Testosterone ◽

Flying Foxes ◽

Mating Period ◽

Social Challenges ◽

Testosterone Levels ◽

Harem Size ◽

Pteropus Poliocephalus ◽

Original Size ◽

Complex Forms ◽

Free Ranging

Males of many vertebrate species aggressively defend their reproductive interests by monopolizing females, and the ‘challenge hypothesis’ predicts that testosterone levels in reproductive contexts rise to facilitate males' competitive behaviours necessary for meeting social challenges. The hypothesis is successful in explaining patterns of testosterone secretion in many avian species, but remains comparatively unexplored in mammals. ‘Circulating plasma testosterone levels (T)’ were studied in relation to harem maintenance in grey-headed flying-foxes, Pteropus poliocephalus . In this species, harems provide mating opportunities and so a male's ability to maintain a harem is likely to correlate with his fitness. We hypothesized that if T reflect a male's ability to withstand challenges from competitors, then T should be linked to successful harem maintenance. To test this, we temporarily removed males from their territories prior to and during the short mating period, recording their harem sizes both before removal and after reintroduction. Most males successfully reclaimed their territory and a harem, but during the mating period, males with higher T had harems closer to their original size, and males with lower T suffered reduction in harem size. Our findings highlight the role of T in harem maintenance in a major mammalian taxon with complex forms of social organization.

Download Full-text

Movements of Australian flying foxes (Pteropodidae: Megachiroptera).

Australian Journal of Zoology ◽

10.1071/zo9650053 ◽

1965 ◽

Vol 13 (1) ◽

pp. 53 ◽

Cited By ~ 87

Author(s):

JE Nelson

Keyword(s):

Food Supply ◽

Late Summer ◽

Early Summer ◽

Summer Camps ◽

Surrounding Area ◽

Flying Foxes ◽

Coastal Species ◽

Pteropus Poliocephalus ◽

Immature Form

Evidence is presented to show that the coastal species Pteropus poliocephalus and P. gouldi congregate in large camps from early until late summer. In these large summer camps the young are born and raised, the sexes become associated, and conception occurs. The numbers within these camps are influenced by the availability of blossom in the surrounding area. The adults are normally dispersed during the winter while the immature form winter camps. These camps contain a larger percentage of adults in those winters in which blossom is more abundant. The inland species P. scapulatus forms large camps in early summer but the young are born in autumn when the population is dispersed. Since the food supply of P. scapulatus is less dependable and undergoes greater fluctuations than that of the coastal species, P. scapulatus is more nomadic than P. poliocephalus and P. gouldi.

Download Full-text

Flight Physiology of Flying Foxes, Pteropus Poliocephalus

Journal of Experimental Biology ◽

10.1242/jeb.114.1.619 ◽

1985 ◽

Vol 114 (1) ◽

pp. 619-647 ◽

Cited By ~ 7

Author(s):

Roger E. Carpenter

Keyword(s):

Pulmonary Ventilation ◽

Thermal Conductance ◽

Power Input ◽

Allometric Equation ◽

Evaporative Heat Loss ◽

Flying Foxes ◽

Ambient Temperatures ◽

Flight Range ◽

Pteropus Poliocephalus ◽

Ventilation Rates

Oxygen consumption was measured during flight in two flying foxes (Pteropus poliocephalus) at airspeeds of 4–8.6ms−1. There was good agreement with the measured power input of the only previously measured large bat, and with an allometric equation predicting power input for flying vertebrates. Measurements of respiratory exchange ratios, pulmonary water loss, respiratory frequencies, heart rates and body temperatures of both bats flying at intermediate airspeeds were compared with equivalent measurements on other bats or birds in flight. Despite a high non-evaporative thermal conductance in flight, the P. poliocephalus became severely hyperthermic at ambient temperatures (Ta) above 25°C. The failure to dissipate heat as successfully as flying birds at high Ta is apparently the result of an inability to increase pulmonary ventilation rates, and thus increase rates of evaporative heat loss. The effect of airspeed on endurance was measured systematically on one bat. Endurance was not limited by energy reserves at all airspeeds, and flight times were significantly greater at the airspeed of minimum power input (Vmp). The endurance of both bats was so reduced at the higher airspeeds that they would not achieve maximum flight range in still air at the velocity where cost of locomotion is lowest. Contrary to a common assumption, flight range would be maximized at the Vmp.

Download Full-text

Seasonal changes in testicular size, plasma testosterone concentration and body weight in captive flying foxes (Pteropus poliocephalus and P. scapulatus)

Reproduction ◽

10.1530/jrf.0.0920339 ◽

1991 ◽

Vol 92 (2) ◽

pp. 339-346 ◽

Cited By ~ 21

Author(s):

M. A. McGuckin ◽

A. W. Blackshaw

Keyword(s):

Body Weight ◽

Seasonal Changes ◽

Plasma Testosterone ◽

Flying Foxes ◽

Testosterone Concentration ◽

Pteropus Poliocephalus ◽

Testicular Size

Download Full-text

Peripheral plasma progesterone concentrations in pregnant and non-pregnant greyheaded flying-foxes (Pteropus poliocephalus) and little red flying-foxes (P. scapulatus)

Reproduction Fertility and Development ◽

10.1071/rd9951163 ◽

1995 ◽

Vol 7 (5) ◽

pp. 1163 ◽

Cited By ~ 9

Author(s):

PA Towers ◽

L Martin

Keyword(s):

Breeding Season ◽

Plasma Concentrations ◽

Late Pregnancy ◽

Corpora Lutea ◽

Flying Foxes ◽

Plasma Progesterone ◽

Peripheral Plasma ◽

Pteropus Poliocephalus ◽

In The Wild ◽

Gas Chromatography Mass Spectroscopy

Blood was collected from breeding-season and pregnant P. poliocephalus females shot in the wild and from captive pregnant and ovariectomized P. poliocephalus and P. scapulatus females. Peripheral plasma progesterone concentrations measured by radioimmunoassay were similar to those obtained by gas chromatography-mass spectroscopy: in intact non-pregnant P. poliocephalus females without corpora lutea (CLs) values ranged from 2 to 30 ng mL-1; after ovariectomy, they ranged from 1 to 85 ng mL-1. A significant source of progesterone in these bats may be the adrenal. In P. poliocephalus, peripheral plasma progesterone concentrations showed relatively little change over the breeding season or in early pregnancy when a CL formed, but increased from mid pregnancy to reach 200-800 ng mL-1 in late pregnancy. A mid-pregnancy ovary with CL contained 2.80 ng progesterone whereas the contralateral ovary contained 0.13 ng. Overall, CL size decreased during pregnancy and was negatively correlated with plasma progesterone concentrations. In late pregnancy, the main source of progesterone appears to be the placenta; plasma concentrations increase with placental growth and are significantly correlated with placental weight, and placentas contain 4-8 micrograms progesterone g-1. There was no evidence that progesterone concentrations fall before parturition. Limited observations indicated that peripheral progesterone concentrations follow similar patterns in P. scapulatus.

Download Full-text