Flying fox karma sutra - ABC's Scribbly Gum on Grey-headed flying foxes

A roosting flying fox mother and baby (Source: Vivien Jones)

Every March and April, the grey headed flying fox gets in the mood for love.
By Abbie Thomas

Flying foxes breed only once a year, but they really make the most of it. The fun starts in February, when female flying foxes move between 'camps' (large gatherings of flying foxes) and stop over with a particular male. The pair mate many times in the next few days, although it's all just practice, because at this stage the female is not yet fertile.

Upside-down sex
Making love bat-style is not an easy job, especially when you spend most of your life upside down. Both males and females have very sharp teeth, and females may not immediately respond to the overtures of an amorous mate.

He begins by licking her genitals, which can go on for several hours. When he thinks she wants to mate, he'll move up behind her. If she isn't in the mood, she'll turn around on the branch and face him, making it impossible for him to enter her.

Flying fox penises are very long - up to one quarter the length of the body - which helps the male stay firmly inside the female, despite their precarious position.

The female signals when she is ready by stepping off the branch and grabbing hold of the male by his ankles. He holds on to her neck with his teeth and pins her wings to her sides. After all the preparation, copulation is pretty quick and when they are done, the female flies off to mate with many other males over the next few weeks.

Unwelcome lovers
Flying foxes have gained a reputation as a nuisance in Australia. They are noisy and sometimes smelly when they roost in urban areas. They will raid orchards and have destroyed some important trees in the Botanic Gardens in Sydney and Melbourne. But there is another side to this story.

Flying fox numbers have plummeted by 30 per cent in the past decade. Mostly this is due to their natural habitat and food source disappearing. Flying foxes eat gum blossoms, which mostly grows in the tall coastal eucaplypt forests of eastern Australia. This area is also in demand from humans, and vast areas of coastal forest have been cleared to make way for new urban development.

When blossoms are in short supply, hungry flying foxes will raid orchards to find food. In retaliation, farmers will shoot, poison or trap them.

Unfortunately, the fruiting season coincides with the final stages of flying fox pregnancy and lactation. Chances are, any females killed while eating orchard fruit will be pregnant or nursing a baby. Either way, both mother and baby will die.

Rabies fear
Can flying foxes give you rabies? We now know that flying foxes can be infected with a rabies-like disease called bat lyssavirus. Only a small number of wild animals are infective and the infection can only be spread from bat to human through the animal's saliva or possibly through scratches.

So, just being near a roost will not put you at risk of being infected. Health regulations now stipulate that anyone who handles bats of any species should first be vaccinated against rabies.

Pollinators
Flying foxes have now been listed as a vulnerable species, and in the next few years there may be a total ban on killing them. To appease farmers, state governments are investigating the possiblity of subsidising netting, to prevent foxes getting to their crops. But where will flying foxes find their food?

It is important to ensure that enough of their natural habitat, coastal eucalypt forests, is protected to maintain a viable population of these extraordinary creatures. Flying foxes play a significant role in maintaining the forest ecosystem. When they eat fruit and browse on blossoms, they carry seed and pollen from tree to tree, thus spreading the gene pool around and helping to regenerate isolated pockets of forest. If the bats go, this living corridor will also disappear.

Getting involved
If you live in Sydney or Melbourne, the best place to see flying foxes is at the Botanic Gardens. In Sydney, there are also colonies at Pymble and Cabramatta. Away from the cities, there are significant colonies of flying foxes at Wingham and Bellingen in NSW.

Bat facts

• Bats have sex all year round but only produce one baby in April.
• They mate hanging upside down.
• The strong smell of flying foxes is not caused by bat droppings. It comes from an odour the males secrete from glands when they are competing with each-other for females and roosting sites. The smell can be overpowering when tens of thousands of bats roost together in the one colony.
• Australia has 90 species of bats, but only four eat fruit, nectar and pollen- all the rest prefer insects.
• Each baby has an individual smell which the mother uses to locate it.
• Flying foxes, unlike many bats, are not 'blind', but actually have good night vision.
• Flying foxes can live for up to 20 years.
• Flying foxes have at least 20 different calls which are used for communication
• Australia's population of grey headed flying fox Pteropus poliocephalus has declined by 30 per cent in the past decade.
• The main threat to flying foxes is from the clearing of coastal forests which they rely on for blossoms.
• Farmers have culled flying foxes since early settlement, using electrocution, shooting, explosives and chemicals.

Links

SydneyBats
Help restore flying-fox habitat, learn to handle flying-foxes, or help with a bat count

Flying foxes on Bellingen Island
Queensland Conservation Council fact sheet

Bat Atlas
Australian Flying Fox expert Chris Tiddeman's homepage

Credits
With thanks to Peggy Eby and Vivien Jones. All photographs were provided by Vivien Jones, Wildlife Photographer, Bellingen NSW.

• ABC's Scribbly Gum on Grey-headed flying foxes