Flying-foxes

• Non-lethal Control of Flying Foxes
• Understanding flying-foxes
• Living with flying-foxes
• Australian Bat Lyssavirus (ABL)
• Hendra virus

Non-lethal Control of Flying Foxes

As of 1 September 2008, the Environmental Protection Agency, under the Nature Conservation (Wildlife Management) Regulation 2006, (section 185), ceased issuing damage mitigation permits for shooting flying foxes. As a result, any deterrent used for crop protection must be non-lethal.

To assist industry in complying with these changes, the Environmental Protection Agency has provided the following information:

Fact sheet: Damage mitigation methods for flying foxes
A fact sheet has been developed outlining the currently available non-lethal deterrents.

Guideline: Euthanasia of flying foxes trapped in orchard nets
A guideline has been developed describing how flying foxes may be euthanised in certain circumstances. These circumstances are limited and specific. A form is also provided that must be completed and retained following each incident of a flying fox being euthanised.

Record of Observation Form
This form will be used to inform government, and the fruit growing industry on the effectiveness of non-lethal controls for deterring flying foxes. Fruit growers are urged to record their observations throughout the fruit growing season and forward these records to the Department of Primary Industries and Fisheries for analysis and advice back to industry.

Understanding flying-foxes

Flying mammals

Grey-headed
flying-fox

On wings of skin stretched over much-elongated fingers and forearms, bats take to the air: the only group of mammals capable of active flight. Fossils show us that flying-foxes have been a part of the night sky for more than 35 million years. These bats may have been seizing on an opportunity to fill airspace left by the mainly day-flying birds.

There are two types of bats, the flying-foxes and their relatives, and the insectivorous bats (micro-bats). These two types of bats appear to have evolved separately, making them distinct groups of mammals. The ancestors of today's flying-foxes may have evolved from a primitive primate meaning humans and flying-foxes may actually share a common ancestry.

The flying-foxes and their relatives are all fruit and nectar feeders. They range in size from the tiny blossom-bats that could fit in the palm of a human hand through to the more familiar flying-foxes with a "wingspan" of more than a metre.

Night vision

Black flying-fox

Flying-foxes rely on well-developed vision to see at night - complemented by an excellent sense of smell to locate food. Their large, forward-facing eyes give them binocular vision while mirror-like retinas reflect and capture the limited available light. Their sight allows them to use rivers, roads and other features as navigation aids. And with highly developed memories, flying-foxes can easily find previously-visited feeding sites and roosts.

Which bats are which and what bats are where?

There are four species of flying-fox that you are likely to see in Queensland with another two species living in the Torres Strait Islands and third, the bare-backed fruit-bat Dobsonia moluccensis, that only occurs in northern Cape York. There is also a mystery species, the dusky flying-fox Pteropus brunneus that is only known from one specimen taken from Percy Island off the central coast of Queensland in the 1870s. It has never been seen again and is believed to be extinct.

The flying-fox family also includes four other closely-related species of bat. These are the blossom-bats (two species) and the tube-nosed bats (one species in Queensland and one from Moa Island in Torres Strait).

The following table lists the species found in Queensland and where they are likely to occur.

Species	Habitat and distribution
Bare-backed fruit-bat Dobsonia moluccensis	Often roosts under piles of boulders and dense vegetation; found in northern Cape York.
Black flying-fox Pteropus alecto	Usually form camps in mangroves or paperbark swamps; found throughout eastern Queensland.
Common blossom-bat Syconycteris australis	Lives in rainforest in north Queensland and also heathland, paperbark swamp and coastal eucalypt forest in southern Queensland.
Dusky flying-fox Pteropus brunneus	Only one specimen known from Percy Island off the coast of central Queensland.
Eastern tube-nosed bat Nyctimene robinsoni	Usually found in rainforest throughout eastern Queensland.
Grey-headed flying-fox Pteropus poliocephalus	It can be found in open forest and rainforests along the east coast of mainland Australia south of Rockhampton.
Little red flying-fox Pteropus scapulatus	This species is nomadic forming temporary roosts in open forest, woodland, paperbark swamps and mangroves where trees are in flower or fruit. It occurs over much of Queensland.
Northern blossom-bat Macroglossus minimus	Found across a range of vegetation types from mangroves to rainforests in Cape York and north-east Queensland.
Spectacled flying-fox Pteropus conspicillatus	Found in or near rainforest in north-east Queensland.
Torresian tube-nosed bat Nyctimene vizcaccia	Occurs in rainforest on Moa Island in Torres Strait but also occurs in Papua New Guinea and the Solomon Islands.

The social life of a flying-fox

Flying-foxes are social animals that usually lives in large colonies or camps. Their roosts can be as small as a dozen animals but usually number in the tens or hundreds of thousands. A temporary camp of little red flying-foxes may mass together one million individuals; with roost trees bending and breaking under their weight. These camps are at their largest when the flying-foxes are breeding.

Camps are often semi-permanent, sometimes dispersing seasonally or when food is no longer available nearby or an area is overtaken by the impacts of encroaching development.

Predators

By living in large numbers, flying-foxes are little affected by predators like pythons, owls and sea-eagles that only take a few individuals and leave the rest of the camp intact.

Breeding

For three species of flying-fox (black, grey-headed and spectacled), one young is born in spring or summer after a five to six month gestation period. The young bats are carried by the mother for three or four weeks and then left at a roost until they start to fly when two to three months old. The young are weaned when they are five to six months old allowing the parents to gather in large camps and mate again.

The little red flying-fox follows a similar pattern but is six months out of sequence with the other species; its young being born in late autumn or early winter. This species forms enormous breeding camps of up to a million individuals in late spring and early summer. The little red flying-fox is highly nomadic, moving camp every one to two months to feed on new patches of flowering trees.

Flying-fox language

Once at a roost or when feeding, flying-foxes "squabble" loudly. At first, what appears to be a mixture of screeches and cackles is actually a language that allows them to establish their personal roost sites or feeding territories, ward off rivals, stay in touch with their offspring and warn others of possible threats. The grey-headed flying-fox is known to have more than 30 specific calls. By listening and watching, it may be possible to link some of the flying-fox's behaviour to the calls it makes.

Feeding, pollination and seed dispersal

Flying-foxes need access to sources of flowering and fruiting trees that can sustain their large colonies. They leave their roosts at dusk using their well-developed sense of smell to relocate known feeding sites or search for new ones, flying up to 50km in a night. The spectacled flying-fox always camps near rainforest and is a specialist fruit-eater known to disperse the seeds of at least 26 species of rainforest canopy tree.

In their travels, flying-foxes disperse seeds in their droppings and carry a dusting of pollen from tree to tree, fertilising flowers as they feed. Eucalypts rely heavily on these pollinators, producing most of their nectar and pollen at night to coincide with when bats are active. Without flying-foxes, there is less cross-pollination between trees, particularly over larger distances; and less seed is set.

Watching bats

With forests continuing to give way to expanding settled areas it is important to watch out for the well-being of remaining flying-fox camps to ensure the health of the habitats that rely on them. At times, the Queensland Parks and Wildlife Service will carry out bat counts to check how these remaining camps are coping with the pressures of shrinking habitat.

Watching flying-foxes and how they behave and interact with others can help you to understand how these fascinating creatures live: when they have young, what they eat, when they move to new feeding sites, and how changes to the weather and surrounding environment affect their behaviour and health - and warn us about emerging risks to their survival.

Living with flying-foxes

Encounters with bats

With fewer available habitat areas there are fewer flying-foxes than there used to be. The grey-headed flying-fox is now listed nationally as vulnerable. These remaining flying-foxes are now concentrated in a smaller number of large camps. And yet, the ability to fly considerable distances often brings them into backyards and orchards in search of fruit and flowers; creating the perception that flying-foxes are as abundant as they ever were and their long-term survival is not at risk.

As their habitat disappears, other environmental factors begin to have greater impact. Poor flowering and fruiting brought on by drought, cyclones and unseasonably wet weather or fires could remove critical seasonal food sources. People disturbing maternal roost sites and ongoing tree clearing could reduce the number of available roosts. If these events were to coincide with the flying-fox's breeding season for a number of years, local extinctions could occur and ultimately lead to the extinction of some species.

• Living with flying-foxes: Health and conservation issues for people living near flying-fox communities
• And what if there were no bats left - a "Flying-fox fable"

Strangers in the night

Flying-foxes can also be relatively secretive. Even though there can be up to a million individuals in a single camp, it is unusual to see more than a few feeding in a tree at the one time. It is only when they are roosting or regularly visiting a feeding site (particularly if it is an orchard) that they draw attention to themselves. After a feeding site has been used, flying-foxes often leave behind half-eaten fruit, small pellets of mouthed fruit pulp, broken off sprigs of eucalypt flowers, or the pasty droppings that have been squirted out onto a wall, the washing or a parked car as the bat jettisons some weight to make flying easier. These flying-foxes have been annoyances for as long as there have been backyards and orchards but now flying-foxes and people cross paths far more frequently as urban development replaces what was once flying-fox habitat.

Flying-fox neighbours

Living next door to 100,000 animals of any sort can take some getting used to. When they are active and noisy at night, prone to smell, eat the fruit from your trees and poo on your walls, it's time to consider your options.

Many thousands of people are neighbours with flying-fox camps particularly those of the black and grey-headed flying-foxes. The enormous camps of little red flying-foxes can create major problems but these are generally short-lived as they move on in search of new sources of nectar and fruit every one to two months.

While the first reaction to these problems is to get rid of the bats, it is far more practical to face the challenges of living with them, as permanently relocating a camp of flying-foxes can be extremely difficult, if not impossible.

Tips for living with flying-foxes

Don't leave washing out at night. If you do, and your washing is getting "bombed", think about putting up old sheets or a shower curtain on the outside lines of your clothes hoist to protect your washing.

If your washing is stained, the challenge will be to remove it. Soak the item as soon as you can (preferably while the stain is still wet) in a good stain remover. Bleach can be used for white items. Some fruits with coloured flesh that are eaten by flying-foxes (e.g. mulberries) may leave a permanent stain (as any parent of a young child will know).

Claims that flying-fox droppings strip paint from cars and houses are also part of the mythology surrounding these animals. If there is any truth to this it may be due to the droppings drying and peeling off a surface and, if the underlying paint is old, lifting off a patch of the surface paint with it.

Noise and smell are issues when a camp is located nearby or temporarily moves into an area. Over longer periods, people often become accustomed to them and they simply meld into the background with a range of other wild and man-made smells and noises that we all live with.

Little can be done to counter the noise and smell of a temporary camp, but remember, the problem is temporary as the flying-foxes will eventually move on as the seasons change, just as they have done for thousands of years.

In the long-term, a camp may be encouraged to move by planting roost trees further away from houses. Surveys of flying-fox camps in New South Wales have shown that a distance of as little as 100 metres from neighbouring houses can be enough to reduce the noise level of a flying-fox camp to an acceptable level.

Roost trees near housing can be made less attractive by clearing the understorey and even removing some of the branches of the trees to make them less suitable for roosting. Low, dense trees and shrubs planted around fence lines also form a barrier that flying-foxes are unlikely to roost in.

Netting your garden's fruit trees: having your fruit and wildlife too

Damage to local fruit trees at either a backyard or commercial scale can also be a problem. Currently the best solution is to cover trees in netting. This will also protect the trees from bird, possum and rat attack; as well as wind and hail. The netting can even create a microclimate that may improve yield.

Using the right type of netting will protect your fruit. Using the wrong type of netting or badly erected netting may still protect your fruit but it can also injure or kill native birds, flying-foxes and possums if they become entangled.

In some situations, threatened species like the grey-headed flying-fox are even being injured and killed in fruit-tree netting.

With a little forethought and care, backyard fruit trees can be netted so you can have your fruit and wildlife too.

For more information about netting backyard fruit trees, go to the page on how to use netting to protect backyard fruit trees without harming wildlife.

For commercial orchards, the use of netting has been successful but is costly in the short-term and has to be weighed up against the cost of any losses caused by bats and birds. Removable netting is also being trialled on a tropical fruit farm in north Queensland. The Queensland Department of Primary Industries has produced a kit to assess how netting can be applied to orchards called To Net or Not To Net and software called Net Profit? (or a personal questionnaire service) for fruit growers to make financial decisions about netting. Once again, any long-term solutions will need to involve re-establishing areas of native food trees so flying-foxes don't rely on orchards.

Australian Bat Lyssavirus (ABL)

Catching diseases from bats is extremely unlikely. Australian Bat Lyssavirus (ABL) can only be caught from untreated bites or scratches from infected bats. One person has died from lyssavirus from a flying-fox (there has also been a lyssavirus death from a micro-bat). All four common species of flying-fox and at least three species of insectivorous micro-bat can carry ABL. Members of the public should not handle bats.

If you find a sick, injured or orphaned flying-fox, do not touch it. Contact your local wildlife care organisation or the department hotline on 1300 130 372. They will put you in contact with a licensed and fully-vaccinated wildlife rescuer who is trained to handle and care for wildlife.

If the flying-fox shows signs of paralysis, or has come into contact with (i.e. bitten or scratched) a dog or a cat, contact the nearest Department of Primary Industries and Fisheries (DPIF) office or call 13 25 23 as they may wish to inspect the flying-fox before you dispose of it. If the flying-fox has come into contact (i.e. bitten or scratched) a person, contact the nearest Public Health Unit or your GP immediately. Do not dispose of the flying fox. In both these situations, the flying fox will need to be tested so that definite information is obtained as to whether the flying fox was infected or not. This information is vital to how the situation is then managed.

To dispose of a dead flying fox that is not needed for testing, use a shovel and/or tongs to remove it and then burn or bury it. Do not touch the bat without wearing gloves. If burying it, ensure that the hole is deep enough so that a dog could not dig it up. If the flying fox is needed for testing, you will receive instructions from either DPI&F or Queensland Health respectively about collection of the bat.

More information on Australian Bat Lyssavirus.

Hendra virus

Flying-foxes are also hosts for Hendra virus. It appears that occasionally, Hendra virus spills over from the flying fox population into horses where it causes an infection that often results in the death of the horse. The rarity of infections indicates that these transmissions may only occur under very specific conditions.

As a precautionary measure, horse owners should not feed or water horses beneath trees where flying-foxes roost or visit regularly. As well, if horse owners know there are bats in the area, they should contact their veterinarian if any of their horses become ill showing signs that include fever, respiratory problems, colic or neurological signs (like loss of vision, loss of balance). Until the horse is examined and cleared by your veterinarian, horse owners should limit contact with their sick horses and avoid contact with any body fluid, including any nasal discharge. If horse owners are at all concerned about their own health, they should contact their GP or their local Public Health Unit and explain their circumstances.

Until more is learnt about the transmission of Hendra virus it is important that members of the public do not handle flying-foxes. Vaccinated wildlife rescuers should observe good hygiene practices when handling flying-foxes.

More information on Hendra virus.

Hendra virus FAQs relating to flying foxes

What do you do if bitten or scratched by a bat?

Do not scrub the wound.

Wash the wound gently but thoroughly for at least five minutes with soap and water. Apply an antiseptic (e.g. povidone iodine or another iodine preparation or ethanol alcohol) and cover the wound.

Contact your doctor or hospital immediately - they will arrange for the vaccinations that are necessary to protect you against ABL. These vaccinations should start as soon as possible after being bitten or scratched.

It is possible to have the bat tested for ABL. The department and Queensland Health will assist with the collection of the bat.

If bat saliva gets into your eyes, nose, or mouth or into an open wound, flush thoroughly with water and seek medical advice immediately.

Prompt treatment following a bite or a scratch is vital.

The future of the flying-fox

The long-term solution to living with flying-foxes is to have a better understanding of their needs both when areas are being protected and before development. Non-residential urban areas such as parklands, golf courses and even cemeteries can be planted out with a range of native trees that provide both fruit (e.g. small-leaved figs) and nectar (e.g. eucalypts and melaleucas). For flying-foxes this would help provide feeding sites away from residential areas and corridors for them to travel between remnant forests.

Similarly, if natural food sources are available at the same time that commercial fruit trees are bearing, flying-foxes are less likely to become a problem.

In short, flying-foxes simply need somewhere to live.

Information sources:
Hall, L., and Richards, R. (2000). Flying foxes and fruit and blossom bats of Australia. Australian Natural History Series. UNSW Press.
Strahan, R. (ed.). (1995). Mammals of Australia, Reed.

Last updated: 08 December 2008

Flying-foxes

• Camp ecology and management
• Flying-fox fable
• Hendra virus FAQs relating to flying foxes
• Netting fruit trees
• Where are Queensland's Flying-foxes?
• No shooting of flying foxes under damage mitigation permits