Fruit availability and utilisation by grey-headed flying foxes (Pteropodidae: Pteropus poliocephalus) in a human-modified environment on the south coast of New South Wales, Australia

Context. Extensive clearing and modi. cation of habitat is likely to change many facets of the environment including climate and regional food resources. Such changes may result in changes in behaviour in highly mobile fauna, such as flying foxes. Aims. The availability of fruit resources was examined to determine whether grey-headed flying foxes ( Pteropus poliocephalus) have feeding preferences related to habitat or dietary items, and whether human usage of the land around the colony site has affected the resources available. Methods. Fruit availability around a colony was monitored from December 2004 to March 2005. Night surveys and faecal analyses were undertaken to determine the distribution of feeding locations, the food species used and the food items consumed by P. poliocephalus. Key results. The amount of food available per hectare in each habitat was similar. However, we found differences in the composition of food trees and the distribution of food resources within each habitat. Ficus species were a major resource with flying foxes observed feeding in figs during every survey and figs identified in droppings over the whole period. Human-modified habitats were used throughout the study period with flying foxes observed in small patches of vegetation and in individual trees without any nearby vegetation. Conclusions. The need for maintaining vegetation, particularly Ficus species, in all areas where flying foxes are found, especially in human-modified habitats and rainforest remnants, is highlighted as this vegetation is of great importance to flying foxes. Other wildlife, such as birds and possums, may also benefit from the maintenance of this vegetation. Implications. Through management of urban resources there is the potential to prevent future conflict situations arising between humans and wildlife, such as can be seen when flying fox colonies are in close proximity to houses

Baseline levels of faecal glucocorticoid metabolites and indications of chronic stress in the vulnerable grey-headed flying-fox, Pteropus poliocephalus

The physiological stress hormone levels and physical condition of captured urban flying-foxes experiencing a food shortage were compared with those of free-living rural flying-foxes with access to supplementary food. Glucocorticoid hormone levels were determined by measuring glucocorticoid metabolites (GCMs) from the faeces of individual animals. The rural flying-foxes were in good condition with high Body Condition Indexes (BCIs) and low levels of GCMs, the range of which may be considered the baseline for this species. In comparison, urban flying-foxes had lower BCIs and elevated levels of GCMs: 75% had levels that were higher than the rural range and 30% were higher by an order of magnitude. Such elevated levels of glucocorticoid ('stress') hormones are characteristic of chronic stress. While urbanisation can cause chronic stress, given the low BCIs observed, it is more likely that food shortage was the major stressor in this study. While the rural male and female flying-foxes showed no significant differences in either their levels of faecal glucocorticoid metabolites or their BCIs, significantly different results were found between male and female urban flying-foxes: males were in relatively better condition than females but had higher levels of faecal glucocorticoid metabolites. The autumn and winter reproductive constraints on food-restricted flying-foxes probably explain the differences observed. Additional droppings collected under the urban colony gave similar results to those collected from captured flying-foxes at the same location, and could be a useful non-invasive method for determining the levels of physiological stress in flying-fox colonies.9 page(s

Estimated time trends in positivity of flying-fox urine for Hendra virus in five contiguous coastal regions of eastern Australia.

<p>The regions were: 1. northern QLD (Cairns to Charters Towers), 2. central QLD (Yeppoon to Gayndah), 3. southern QLD/northern NSW (Redcliffe to Nambucca Heads), 4. central NSW (Port Macquarie to Newcastle), and 5. southern NSW (Avoca to Batemans Bay).</p

Geographic locations of 27 roosts¹ surveyed for Hendra virus in flying-fox pooled urine samples.

<p>(Sydney CP = Sydney Centennial Park). ¹ Roosts with five or more sampling events.</p

[In Press] Estimating flying-fox mortality associated with abandonments of pups and extreme heat events during the austral summer of 2019-20

Abstract. Mass mortalities in flying-foxes occur in summers that reach extremely hot temperatures. In this study, we examine the spatiotemporal distributions of mortality from pup abandonments and extreme heat events in Australian flying-fox camps during the 2019–20 summer. We recorded data on flying-fox mortality in known affected camps and applied a standard method to estimate the number of deaths. Pup mortalities from abandonments were recorded in 10 camps in New South Wales. A minimum estimate of 2612 flying-foxes died in pup abandonments, the majority of which occurred in one camp in Bomaderry. Die-offs from extreme heat events were recorded in 40 camps associated with eight separate heat events in south-eastern Australia. A minimum estimate of 72 175 flying-foxes died during these heat events, which all occurred within the range of the threatened grey-headed flying-fox (Pteropus poliocephalus). Further, 409 and 2251 live flying-foxes were taken into care from pup abandonments and heat events respectively. The minimum mortality estimated represents the highest recorded mortality of Australian flying-foxes within a single summer. This highlights a need to restore vegetation in flying-fox foraging areas and camps, address anthropogenic climate change and gather more empirical data to inform heat stress interventions to minimise flying-fox mortalities