How do Grey-Headed Flying-Foxes help our bushland?
Grey-headed Flying-foxes primarily eat the nectar, pollen, flowers and fruit of native plants. While they eat, they're also doing the important job of spreading seeds and pollinating other plants. While eating, their pointed noses and fur become covered in pollen. When the Flying-fox moves to the next tree, it pollinates other native plants.
Since Flying-foxes can travel further than bees and birds, sometimes travelling hundreds of kilometres in a single night, they can spread more seeds over a larger area and do more pollinating than any other Australian animal or insect. The fact they're nocturnal also means that Flying-foxes are the only species who can pollinate certain native plants which only flower at night.
This is what earns Flying-foxes the title of "Nature's Bush Regenerator". Their hard work spreading seeds and pollen has a flow-on effect for all the other species living in our bushland. They regenerate forests, giving other animals food and habitat – this is known as a keystone species. Looking after Grey-headed Flying-foxes gives other threatened species like koalas and possums a better chance at survival too.
Nature's Bush Regenerator
Grey-Headed Flying-Foxes are the key to keeping our forests healthy!
Why are Grey-Headed Flying-Foxes in trouble?
Flying-foxes are running out of native food and habitat. They are considered vulnerable to extinction under the Commonwealth Environment Protection Conservation Act 1999. Their population has declined by 95% over the last century – a rate which would see them extinct by 2050.
Grey-Headed Flying-Foxes live on the East Coast of Australia, generally within 200km of the coastline, spreading from as far north as Rockhampton to as far south as Melbourne. Land clearing and rapid urbanisation along the coastline means Flying-foxes are being left with no choice but to set up camp in urban areas. Then when there's no native plants and pollen to feast on, Flying-foxes are forced to eat our backyard fruit trees or commercial crops.
Because of this, some people see Flying-foxes as a pest. Man-made structures like fruit tree netting, barbed wire fences, power lines or exotic garden plantings such as the cocos palm account for many Flying-fox deaths.
Flying-foxes are also very vulnerable to heat stress. On hot days (above 38°C) they will try to cool themselves down by fanning themselves with their wings, panting, licking themselves, or clumping together in shadier, lower-down branches. Temperatures above 42°C can cause mass dying events in colonies, as Flying-foxes overheat and drop dead from their camp.
Flying-Fox populations in Shellharbour
In Shellharbour, we have our very own native Grey-headed Flying-fox colony to protect and care for!
Our local colony's population usually ranges between 1,000 - 6,000 individuals, depending on seasonal food availability within the Illawarra.
Did you know that Blackbutt Forest Reserve is home to an important maternity camp of Grey-Headed Flying-Foxes?
Blackbutt Forest is a significant patch of local bushland, containing nearly 70ha of vegetation across the suburbs of Blackbutt and Barrack Heights. The landscape has been carved through ancient erosion processes, and is part of what is known as the Sydney-Gunnedah-Bowen Basin System.
The Blackbutt camp population of Grey-headed Flying-foxes ranges from approximately 1,000 to 6,000 individuals, depending on the seasonal food resources available in the Illawarra region. The camp is one of a network of hundreds of camps along the east coast of Australia. Camps are generally only found within 200km of the eastern coast of Australia, from Rockhampton in Queensland to Adelaide in South Australia. However, in times of food shortages, they may be found in unusual locations.
The Reserve is home to a diverse range of plants and animals, including those threatened with extinction like the Spiked Riceflower and Grey-headed Flying-foxes. It is also home to special and rare ecosystems, including Illawarra Subtropical Rainforest and Illawarra Lowlands Grassy Woodlands.
Blackbutt Forest provides native and seasonal food resources for Grey-headed Flying-foxes. Blackbutt Dam provides a permanent water supply that’s perfect for a sunset dip before a night out foraging. Flying-foxes drink in an unconventional way - they drench their belly fur by trailing their bodies along the water surface, before heading to a nearby tree to hang upside down and lick the water off their fur!
The Blackbutt Reserve camp is known as a maternity camp, where young Grey-headed Flying-foxes are born from September to October. Not all Flying-fox camps are used as a maternity camp, where annual breeding and rearing of young takes place. Here at Blackbutt though, we have been lucky enough to see Flying-fox pups appear every year since the camp was first established in late 2010. After the adults mate in late Summer through to Autumn, a single pup is born in late spring.
Pups spend the first six weeks of their life clinging to their mother’s belly fur, feeding on milk and being carried each night as the mother flies out in search of food. When the pup grows too big to be carried, they remain close to their mothers in the canopy, feeding during the day and learning to fly. At night, larger pups are left together in a ‘crèche tree,’ selected for its dense canopy cover that offers greater protection for the pups from potential predators such as large forest owls. When the mother returns from foraging at dawn the following morning she can identify her pup by its unique smell and call. Pups remain dependent on their mothers for the first five to six months of their life, before learning to forage at night and care for themselves.
Croom Reserve is an important biodiversity corridor for the native species of Shellharbour and the surrounding regions, including our Grey-headed Flying-fox.
When we say corridor, we mean smaller patches of native vegetation that are separated by urban development, but still close enough to create a link or 'corridor' for native animals to travel between. They can act as rest stops to help connect species to larger patches of vegetation like Blackbutt Forest.
Croom Reserve covers an area of approximately 30 hectares and mostly consists of Illawarra Lowlands Grassy Woodland, similar to Blackbutt Forest. Its smaller size and isolated location (being surrounded by residential and commercial development) makes it suitable for a fly-in and fly-out snack on the flowering Eucalypts, but it's unlikely that additional planting at the site will lead to a permanent Grey-Headed Flying-Fox camp.
It's important that we maintain the biodiversity of smaller sites like these - that is, making sure there are a wide range of native flora and fauna present - as a backup foraging site for our Grey-Headed Flying-Foxes. The more variety of food we can provide in natural habitats, the less likely it makes Flying-Foxes to have a nibble on our backyard fruit trees!
Disturbances to the Flying-fox camp within Blackbutt Forest predominately occurs during the day, when the animals are sleeping or resting after being out foraging all night. It is often during the Summer months when temperatures are high that disturbance to the camp becomes an extra stress to the animals. Activities such as mountain biking or large groups of people around the camp can lead to additional stress and disturbance.
In recent years unforgiving Aussie summers have led to large scale death of Flying-foxes, including babies that are especially vulnerable during heat events. Here in Shellharbour, climate modelling shows the region is expected to see more hot days above 35°C in the future.
Flying-Fox Management
Flying-foxes communicate with one another through scent.
Camps tend to smell the strongest during mating season (January - May) because males stake their territory and attract a mate through scent-marking.
Odours are also used to locate camp trees, and to help mums identify their pups in crèche trees.
Despite their strong smell, Flying-foxes actually spend most of their day grooming themselves. They even turn right side up when they need to go to the toilet, to keep themselves clean!
Grey-headed Flying-foxes are a super social animal, and always down for a chat! They are noisiest at dusk and dawn, as camps experience a burst of activity with Flying-foxes bickering over food or their favourite tree branch.
Noise levels get worse when Flying-foxes are frightened or stressed. This is usually caused by human activity or the presence of predators such as dogs, cats or native birds-of-prey.
It is very unlikely that you could get sick from a Flying-fox.
Grey-headed Flying-foxes can carry two diseases that can be dangerous for humans, Australian bat lyssavirus and Hendra virus, but the only way to contract these diseases is through a Flying-fox scratch or bite. Human infections with these viruses are very rare.
The best way to keep yourself safe is by not handling or having direct contact with a Flying-fox.
Flying-fox droppings, like all animal droppings, should be dealt with while wearing disposable gloves, and ideally a face mask.
To remove stains from clothing, soak the item as soon as possible with stain remover. Use bleach for white items.
To remove droppings from objects like cars or outdoor furniture, soak the droppings with a soapy water solution before wiping off with a rag or sponge, or use a pressure washer if appropriate.
Be sure to wash your hands thoroughly with hot, soapy water afterwards.
It's actually far more likely to be the other way around. Pet dogs and cats sometimes hunt and injure Flying-foxes.
If you notice that Flying-foxes are visiting your backyard, it might be a good idea to keep your pets inside at night. This will protect your pet against any potential Flying-fox bites or scratches, and protect flying-foxes from being injured.
Transmission of diseases between Flying-foxes and domestic pets are very rare. If your pet becomes sick after coming into contact with a Flying-fox, please seek out veterinarian advice.
Flying-foxes will set up camp close to a food source and take off again once the food runs out. This means that Flying-foxes will usually be 'seasonal' visitors, and not necessarily stick around your place for more than a few months at a time.
Preparing for Flying-fox season at your place might look like:
- Bringing your washing in at night (especially if your clothesline is under a tree) to avoid droppings.
- Parking your car under a shelter or using a car cover to prevent damage from droppings.
- Trimming back tree branches and removing fruit to make your backyard less appealing to Flying-foxes.
- Netting fruiting trees to prevent Flying-foxes from having a nibble - just make sure you're using the right type of netting!
- Consider planting appropriate foraging or habitat trees on your property further away from your house, to draw Flying-foxes away from the home.
- Setting up a predator 'decoy' (such as an owl statue) in the branches of fruiting trees.
What can I do to help?
To protect yourself against potential scratches or bites, please do not handle a sick or injured animal.
Please phone WIRES on 1300 094 737.
If you come across a deceased Flying-fox on Council land like Blackbutt Forest or Croom Reserve, please call Council on 02 4221 6111.
Interested in becoming a citizen scientist? You can download the CAUL Wildlife app through Google Play or the Apple Store to start recording Flying-foxes in your area, and share the photos or videos with our citizen scientist community!
Register your interest to become a planter and help grow future forests that will feed and house our own Grey-headed Flying-fox colony.
We'll reach out when our next community planting day is coming up!
