Grey-headed Flying-fox Management Strategy for the Lower Hunter Grey-headed Flying-fox


Table 17.7Electrocution and Entanglement



Download 1.72 Mb.
Page9/22
Date19.10.2016
Size1.72 Mb.
#4690
1   ...   5   6   7   8   9   10   11   12   ...   22

Table 17.7Electrocution and Entanglement

GHFF injury and death can occur from contact with various types of infrastructure occurring in the urban and rural landscape, as well as collision with motor vehicles. Numbers of such events are not routinely captured, although in a banding study between 1988 and 1999, Tidemann (1999) identified the cause of death of recovered GHFFs as follows; 71% were electrocuted on powerlines, 21% died in netting over fruit trees, 5% had gunshot wounds and 3% died as a result of collision with motor vehicles. GHFF also become entangled in barbed-wire fencing (Halpin et al. 1999, van der Ree 1999) and there is a report of an adult male Little Red Flying-fox dying from impact with a turbine at a wind farm (posted on ABS discussion list 12 /12 /12).


The low reproductive output of the GHFF (refer to Section 17.12.1) makes the species vulnerable to the loss of individuals, particularly females, from the population. With an increase in the availability of reliable forage within cities (McDonald-Madden 2005) and the occurrence of camps in urban areas, the GHFF population is increasingly exposed to risk of collision, electrocution and entanglement. There are options available to reduce the number of deaths, such as the use of insulated or underground powerlines and the use of wildlife-safe netting and fencing.
Table 17.8Potential GHFF Camp Conflict

Name

Purpose

Coastal Floodplain

Permanent Water <500 m

Can Support Vegetation >8 m

Foraging Habitat <20 km

Risk

Comments

Cessnock LGA

East Cessnock

Residential









High

Existing camp within 300 m with potential to move closer.

Civic

Employment









Moderate

Revegetation of gully or around dams to the north-west and south may require buffer.

Government Road

Residential



? wastewater treatment ponds





Moderate

Camp could establish in drainage lines within Cessnock State Forest, along the eastern boundary or along Black Creek.

Sanctuary Village

Conservation and urban

association







Moderate

Revegetation along Congewai Creek (proposed urban) and Quorrobolong Creek (existing urban) may require buffer.

Bellbird

Residential



? large farm dams





Low

Revegetation along Limestone Creek may require buffer.

Nulkaba

Residential



? dams





Low

Revegetation along Oaky Creek may require buffer.

Sweetwater / Huntlee

Urban / Conservation



? Black Creek





Low

Revegetation of Black Creek within conservation areas could require a buffer from proposed urban areas. Buffer should be absorbed within the urban area.

Kitchener

Residential



? large dam Black Creek





Very low

-

Gingers Lane

Residential









-

-

Averys Lane

Residential

associated

? dams





-

-

Cliftleigh

Residential

associated

? dams





-

-

Greta Migrant Camp

Urban









-

-

Cessnock / Maitland / Newcastle LGAs

Freight Hub

Freight



? dams





Low – moderate

Large site with multiple creeks in proximity to Black Hill camp which was abandoned c1990s. Buffers to suitable GHFF roosting areas should be incorporated.

Maitland LGA

Aberglasslyn

Residential

associated







High

Four kilometres from Lorn, along the Hunter River. Revegetation along the Hunter requires buffer.

Gillieston Heights

Residential

associated

? dam





-

-

Farley

Urban

associated







-

-

Rutherford

Employment









-

-

Rutherford Business Park

Employment

associated







-

-

Lochinvar

Residential



? dams





-

-

Anambah

Residential



? dams





-

-

Thornton

Residential









Low

Risk is from Four Mile Creek which is outside development area and unvegetated.

Port Stephens LGA

Tomago

Employment









High

Revegetation of the bank of the North Channel of the Hunter River could attract GHFF, buffers should be incorporated.

North Raymond Terrace

Residential









Moderate

Between the Williams River and Grahamstown Dam, revegetation of swamp or tributaries may need buffers.

Tanilba Bay

Residential









Low

Situated between Tilligerry Creek and Port Stephens, introduction of tall vegetation may require buffers.

Karuah

Residential









Low

Frontage to Karuah River, Little Swan Bay and Port Stephens suggests buffers should be considered where riparian areas are being revegetated.

Wallalong

Urban









-

-

Medowie

Residential









-

-

Air Employment

Employment









-

-

Anna Bay

Residential









-

-

Newcastle LGA

Minmi

Residential









Low-moderate

Minmi Creek and tributaries of Hexam Swamp may require buffers.

Newcastle / Lake Macquarie LGAs

Link Road South

Residential









Low

Vegetated riparian areas retained along Brush Creek and tributaries may require buffers.

Link Road North

Residential









Low

Vegetated riparian areas retained along Maryland Creek and tributaries may require buffers.

Lake Macquarie LGA

South Morisset

Residential









Moderate

Pourmalong Creek currently suitable for roosting GHFF. Appropriate buffers required.

North Morisset

Residential









Moderate

Vegetated section of Stockton Creek and its tributaries require buffers.

Wyee

Residential









Moderate

Vegetated and potentially rehabilitated section of Mannering Creek and its swamps require buffers.

Middle Camp

Urban









Moderate

Buffer vegetated Middle Camp Gully.

Nords Wharf

Urban









Moderate

Lake Macquarie requires buffers.

Gwandalan

Urban









Moderate

Lake Macquarie and tributaries require buffers.

Cooranbong

Residential









Low

Revegetation along Jigadee Creek and adjacent vegetated drainage lines may require buffers.

Catherine Hill Bay

Urban









Low

-

Fennel

Residential

associated







Low

Retention of riparian vegetation along Marmong Creek requires buffers.

West Wallsend

Employment









Low

Riparian areas along Slatey Creek on the eastern side of the proposed area may require buffers.

Pambulong

Residential

associated







-

-


Table 17.9Competition

Competition for resources between flying-fox species may be impacting on the GHFF population. In particular, shifts in the range of all but the Little Red Flying-fox have been recorded in the last decade. The cause of these shifts remains unclear, reasons could include accidental movement (e.g. caused by strong winds), human translocation (e.g. rehabilitated or pet flying-foxes), changes in habitat due to climate change or land clearing (Tidemann 1999, Parsons et al. 2010), or a successful natural shift in the distribution of Australian Pteropid bats in response to the highly variable Australian climate (Parsons et al. 2010).


The Black Flying-fox experienced a southerly range extension of 750 km in the past 75 years (Eby 2000, Roberts et al. 2012a). In 1999, the GHFF range was thought to have retreated southerly by approximately 750 km (Tidemann 1999), although a systematic evaluation found no evidence of a latitudinal shift in the range of this species (Roberts et al. 2012a). Instead, there is evidence of westward expansion into urban areas. Small camps (generally <1,000) have recently been established in Canberra, Adelaide and Bendigo.
It remains unclear how shifts in distribution of the Black Flying-fox will affect the viability of the GHFF population. Expansion of the southern limit of Black Flying-foxes has increased the area of overlap with GHFFs. The increased number of Black Flying-foxes in new areas has been without a commensurate increase in overall numbers of flying-foxes, indicating a negative impact on GHFFs (Roberts et al. 2012a). The Black Flying-fox may displace the GHFF as it is believed that the Black Flying-fox out competes the GHFF and is more of a generalist (Tidemann 1999, BCC 2010). The Lower Hunter is located in the middle of the current GHFF distribution and therefore it is unlikely that GHFF will disappear from this area. Although numbers of Black Flying-fox are increasing in the Lower Hunter (T. Pearson, Macquarie University, unpublished data) and the presence of this species may, with time, reduce the number of GHFF.
The level of hybridisation between the three larger Pteropid species (P. alecto, P. conspicillatus and P. poliocephalus) remains unclear. Observations of inter-species mating (Lowe pers. com. in Parsons et al. 2010) and reports of hybrids of P. alecto /poliocephalus (DECCW 2009a) have been made.

Table 17.10Public Perception

The GHFF, along with bats in general, is poorly regarded by the general public. From the time of European settlement, flying-foxes were identified with disease and crop losses (Eby & Lunney 2002). The earliest broad-scale study of the GHFF was undertaken by Francis Ratcliff c1930. It failed to support the notion that orchard losses were either significant, or able to be suitably reduced through culling (Ratcliff 1931), however these findings were largely ignored. GHFFs were exempt from the general protections provided to most native animals in NSW under the NPW Act 1974 and it was not until 1986 that the GHFF was added as a protected species. The changed status to a protected species regulated legal culling of GHFF; however unregulated culling of GHFF individuals occurred in NSW well into the 1990s, including the Lower Hunter (e.g. Black Hill camp).


In the Lower Hunter, commercial orchards are not currently a source of conflict between humans and the GHFF (cf 1990s), with urban roost sites and the associated impacts to humans being the contemporary point of contention. Urban roost site conflict results when GHFF unexpectedly establish in new locations where they have not camped for many decades, or when development is permitted too close to existing areas used by roosting GHFF. Many conflict sites are a legacy of poor historical planning decisions. Forward-thinking and pro-active planning and funding decisions would support better management of roosting GHFF sites in the future.
Accepted as a species of conservation concern internationally (IUCN) and by the Federal, NSW and Victorian governments, the conservation outcomes for the GHFF are impacted by community apathy, the influence of politics on decision-making and misinformation about the health risks associated with flying-foxes. Improved community education programs are required at all levels to counteract the negativity toward GHFF and ensure that future generations are familiar with the science behind its role in our ecosystems, biology and management.

Table 17.11Climate Change

17.11.1Food Shortages

Extreme weather events such as floods and droughts can cause food shortages for the GHFF by affecting flowering and fruiting patterns in native plants. Impacts of food shortages are further compounded by the natural irregularity of flowering in key eucalypt species for the GHFF (e.g. in association with La Niña and El Niño events; Tidemann 1999). Whilst patterns of abundance and shortage are natural, the temporal and spatial extents of food shortages seem to be increasing.


During food shortages in 2010, new camps were established across eastern Australia, including Albury, Canberra, Bendigo and Adelaide. New camps were also observed in the Lower Hunter: Hannan Street, Lorn, Tocal, Raymond Terrace and possibly Blackalls Park. Whilst some of these camps were temporary, others remain in use. A concurrent study at the Botanic Gardens Sydney confirmed that establishment of these new camps allowed animals affected by the food shortage to reduce their daily energetic requirements by reducing commuting distances between roosts and feeding areas (Eby et al. 2012 and unpublished data).
Whilst we cannot control the climate or the flowering phenology of Australia’s Myrtaceous species, the maintenance of productive forested areas containing GHFF dietary plants may be crucial in reducing the effects of climate change on food shortages. Furthermore, a network of appropriate roosting habitat across the coastal floodplains and associated upland areas would increase the capacity for GHFF to adapt to changes in foraging resources that may result from climate change.
17.11.2Intense Storms and Heat Waves

Increased frequency and severity of extreme weather events impact GHFF directly and can result in significant number of animals being removed from the population. Heat waves result in GHFF succumbing to dehydration and hyperthermia when ambient temperatures rise above 40˚C, resulting in mass deaths (Welbergen et al. 2008). Deaths of GHFFs from extreme heat were recorded in 10 of the 11 years between 2002 and 2012 in camps across the range of the animals (Welbergen et al. 2008, P. Eby unpublished data), including approximately 2600 deaths in the Blackbutt Reserve camp in January 2006 (10% of that camp) and 40 deaths in January 2007 (1%).


Management of GHFF camps should consider the potential for increased frequency and severity of extreme weather events. There is evidence that complex vegetation structure and proximity to significant water bodies assists flying-foxes in managing heat waves by providing shade and protection from hot, dry winds (J. Welbergen pers com.) and opportunities to reduce body heat by wetting their bodies through direct contact with water.
Both hail and strong winds are also known to cause injury and death. For example, a hail storm occurring on 17 November 2012 in Brisbane affected 86 Black and Grey-headed Flying-foxes resulting in injuries such as broken legs and wings, and resulting in dependent young requiring care (http://www.couriermail.com.au/news/queensland/native-wildlife-downed-by-freak-hailstorms/story-e6freoof-1226522293129). In 2003, strong winds brought down roost trees killing approximately 200 adults at the Wingham Brush camp (A. Boardman pers com.).


Download 1.72 Mb.

Share with your friends:
1   ...   5   6   7   8   9   10   11   12   ...   22




The database is protected by copyright ©ininet.org 2024
send message

    Main page