Welcome to our series of educational articles on pollinating mammals – our friendly gardeners!

Today, Ella shares an article on the flying foxes of Brisbane, Australia.

In the city of Brisbane, at the close of day, the dusk sky is often filled with the beating of outstretched wings, a flight animal on the move. They could be mistaken for birds, but in fact they are the only mammal capable of flight, the flying fox, also known as a mega-bat. 

Bats or flying foxes belong to the order Chiroptera, meaning ‘hand wing’. The structure of a bat wing consists of a thin elastic membrane stretched across four elongated fingers and a thumb. There are four mainland species of flying fox in Australia: the speckled, the black, the grey-headed, and the little red flying fox. Flying foxes, unlike micro-bats, use sight and smell to navigate and locate food rather than echolocation. 

Flying foxes play an important role pollinating and dispersing the seeds of hundreds of plant speacies. They are considered a keystone species, a species that plays a key role in contributing to the health and regeneration of Australian native forests. 

During the day, bats hang out in large camps (or colonies), usually in tall trees close to rivers, creeks, or water. Highly social and very vocal, flying foxes make a range of different vocalisations to communicate. At dusk, they leave their camps to go in search of food. Their favourite food is the pollen and nectar of the eucalypt blossom, melaleuca (paperbark) and banksia flowers, and rainforest fruits including figs and lilly pillies. They will eat the stamen and flower parts, the leaves and bark. They will also eat any suitable, available fruit from fruiting plants in home gardens or orchards. 

Flying foxes are important nocturnal pollinators. Moving amongst the trees, feeding on the nectar of flowers, they become covered with pollen that sticks to their fur. When they move from tree to tree, which may be kilometres apart, the collected pollen dust falls on the next flower’s stigma. This way, they pollinate many rainforest and hardwood trees. These are the types of trees that form the scaffolding of native forests, providing habitat for many native species, including the Koala. There are a few species that only produce nectar at night, coinciding with flying foxes nocturnal feeding patterns.  

As flying foxes can travel up to 50 kilometres in one night, they can disperse up to 60,000 seeds across ecosystems in one night. The transit time of flying-fox gut-passage is fast, within half an hour, but seeds can also be retained in the gut for up to 24 hours. 

The ways they disperse seeds can be by eating the fruit and spitting out the remains as ejecta pellets, carrying and dropping fruit away from the source, or digesting the fruit and defecating at a different location. Seeds dropped away from a parent plant mean greater genetic diversity, which prevents inbreeding and makes species stronger. By being dropped far from the parent plant, a seed may have a better chance to survive and grow, particularly if there is competition for sunlight or water near the parent plant.

Ways we can help the flying forest gardeners:

• Plant native habitat trees such a fruiting rainforest trees or eucalypt trees that will provide sources of food for flying foxes. If you don’t live in Australia, there may be other native trees in your area that flying foxes or bats can enjoy. 
• Barbed wire fences are a considerable threat to flying foxes. If you can, replace it with fencing that a flying fox cannot get caught in. 
• Flying foxes can also get trapped in fruit nets. Make sure you have netting with a knitted mesh and a small aperture less than 5mm by 5mm, woven from strands 500 microns thick (minimum). 
• Coco palms are harmful to flying foxes. There are other palms that you can replace them with such as Bangalow or Alexander palms.