Austronomous australis (formerly Tadarida australis)
- Colour: It has dark brown to black fur with a bright white-stripe at the junction of the body and wings. Some individuals also have an area of white-fur on the chest.
- Size: The White-striped Bat (Tadarida australis) is one of the largest insectivorous (microbats) in Australia (around 40g) adult weight.
- The White-striped Bat is in the ‘freetail’ family (Molossidae) which have a strong, stiff tail projecting beyond the tail membrane.
- Call: unlike other microbats part of the White-striped Bats echolocation call is audible. Most people with reasonable high frequency hearing can identify its distinctive metallic ‘ting ting’ once they’ve been tuned in.
- Diet: insects.
- Movement: it is a fast flyer and tracks the open space above the tree canopy. Its speed gives it a wide foraging range and as a result it is one of the few bats routinely encountered over urban areas.
What to Observe
Absent (if you cannot hear it)
Present (if you can hear the ting ting call)
The number of calls in a 10 minute period in "How Many"
ClimateWatch Science Advisor
The large flight muscles in this species generate significant heat and impose a temperature limit on activity and foraging time. During summer White-striped Bats are restricted to areas where the mean monthly minimum (night-time) temperature does not exceed 20oC. These conditions exist over most of the south-west of Western Australia but this situation is anticipated to change quite rapidly as the result of human-induced climate change. As nocturnal temperatures rise the foraging period available for these bats will be reduced. The initial response may be the cessation of breeding activity. The next will be a contraction in summer range towards the south coast of the State.
The White-striped Bat is easy to detect and its behaviour, distribution, migratory timing and population size are all potential indicators of climate change. Can the White-striped Bat adapt and if so how and where? These are questions you can help us answer.
When To Look
- Best time to listen is around 90 minutes after dark, later on really warm nights.
- You only need to record whether the bat is present or absent but counts of the number of calls (over 10 minutes) may be a useful index of activity levels and can be recorded in the Notes.
- Remember that ‘null’ results are just as important to record as positive contacts (and that things will change seasonally).
Where To Look
- Bullen & McKenzie (2005) found that the White-striped Bat was a partial migrant
- Cawthen (2013) suggests that the White-striped Bat occasionally visits Tasmania.
- During the summer months (the reproductive period) all records were from south of 29oS latitude.
- During the winter months a proportion of the population moved northward into the arid zone as far north as the Great Sandy Desert and Broome.
- Choose a quiet area with an open sky - grassy paddocks, near dams or under street lights may be good spots although this bat can be heard almost anywhere if present.
The map below displays the accumulated observations of these species as reported by ClimateWatch observers, together with the layer showing how the range of the species might change between now and 2085, with orange areas indicating where the species might disappear, and green areas where the species range might expand.
Bullen,R.N. & N. McKenzie (2005). Seasonal range variation of Tadarida australis (Chiroptera : Mollossidae) in Western Australia: the impact of enthalpy. Australian Journal of Zoology 53, 145-156.
Cawthen, L. (2013). 'White-striped freetail bat in Tasmania - resident, vagrant or climate change migrant', Australian Mammology.
Churchill, S. (2008). Australian Bats (2nd Edition). Jacana Books. Allen & Unwin. Crow’s Nest, new South Wales.
Some crickets and cicadas produce sounds at similar frequencies. However these calls are static not moving across the sky at speed.
Did You Know?
These bats are also called ‘mastiff’ bats because their wrinkled facial features resemble those of a mastiff dog.
Listen to the Call