There are two types of bats native to Western Australia: megabats (Flying-foxes) and microbats (insectivorous bats). Megabats weigh over a kilogram and feed mainly on fruits and nectars. Microbats mainly feed on insects and can be as small as 40mm long. Both bats are active in the evening and can be observed when feeding at dusk.
The most common bats found in Cockburn include the adaptable Gould’s Wattled Bat, found in all of the City’s wetlands, White-striped Freetail Bat, one of the few bats whose echolocation calls are audible to human ears, and the Southern Forest Bat, a highly energetic bat, which can hunt their prey with great agility.
Microbats are usually found in wetland areas occupying tree hollows for roosting. They can also be found in residential areas sometimes roosting under eaves and shingles and can even enter living spaces through very small gaps of 1cm diameter. If they are not causing a nuisance there may be no need to evict them, however if they are causing problems, they can be deterred by blocking entry points.
If a flying fox roosts in your backyard it should be left alone as it is likely to move on within a few days.
Bats help to reduce numbers of flying insects like midge, mosquitoes and other insect pests. With one microbat eating the equivalent in weight to 1,000 mosquitos in a night. Microbats are vital in controlling insect numbers and are indispensable in our natural areas.
Most bats cause no problems at all and form part of a natural ecosystem by being pest control agents. Bats will generally not interact with people unless by mistake or if distressed or threatened. Bats are unlikely to cause any physical harm unless injured, cornered or captured.
Nine bat species are found in south-west WA, all are microbats:
- White-striped Freetail Bat (Tadarida australis)
- Southern Freetail Bat (Mormopterus planiceps)
- Gould’s Wattled Bat (Chalinolobus gouldii)
- Chocolate Wattled Bat (Chalinolobus morio)
- Southern Forest Bat (Vespadelus regulus)
- Western False Pipistrelle (Falsistrellus mackenziei)
- Lesser Long-eared Bat (Nyctophilus geoffroyi)
- Gould’s Long-eared Bat (Nyctophilus gouldi)
- Western Long-eared Bat (Nyctophilus major).
In Perth, as with many regions of the world, bat numbers have declined. Reasons include habitat destruction; pesticides; and feral animals (such as European Honey Bees and Rainbow Lorikeets) occupying tree hollows that bats use for roosting.
Bats are a protected species that may carry diseases that can be transmitted to humans through direct contact. Bats may not be captured, moved or relocated without a permit and must be handled by a professional.
The City has invested in bat boxes located in trees in selected conservation reserves to help promote bat activity. If you would like to help build a bat box for a local wetland contact your Resident’s Association. We work with groups to run bat box workshops on request.
The City regularly runs bat night stalks where you can learn more about microbats and see them in the wild! Visit City Events page for the upcoming Bat Night Stalks.