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Microbat Photo Doug BeckersGive insect terminators a roosting place in your backyard

Have you watched bats swooping insects? If you visit a park with streetlights at night and watch - you may be lucky! Insect eating microbats are alive and well in your area.

During summer and autumn, microbats go into a feeding frenzy as they fatten up on insects to see them through the coming winter. Once the nights become cooler and the insects disappear, microbats lower their body temperature and go into a state of mini hibernation until their food returns in spring. Microbats can eat as much as 40% of their own body weight in a single night or several hundred insects per hour.

The smallest microbat weighs only 3 grams - about the same as a single serve sugar sachet or a single A4 sheet of paper. If these tiny bats cannot find a suitable hollow, they can fit into very small gaps and utilise your roof and walls. This is why artificial roost sites are important as they provide an alternative.

Keep microbats out of your walls and roof

Many of our microbat species are hollow dependent which means they live during the daylight hours inside the hollows of trees or branches. Competition from birds, possums and gliders along with the clearing of many old trees means that microbats may find the roof or walls of your home, the perfect roosting place.

In Australia, microbat babies are born in late spring and remain with their mothers until the end of January. Gentle autumn eviction attempts after February and before June make certain that the young are independent. After all, the little bats deserve no harm for taking advantage of 'faulty' homes.

If microbats are evicted correctly, walls can become bat free and the little bats provided with an alternative roost site and retained in the backyard to go about their insect feeding work which is of great benefit to all of us.

If you have microbats in your walls or roof, visit Bat Rescue Inc at www.batrescue.org.au for more detailed information on how to remove them.

What microbats like and dislike:

What microbats like:

  • lots of insects to give them enough supplies to last the winter months.
  • safe places to live. Microbats live in a variety of roosts that vary between species. Some choose caves or mine shafts or storm water pipes, while others use tree hollows, under bark, cracks in posts, dried palms leaves or junction boxes. They are fussy about conditions and will use a particular site at different times of the year.
  • lights to attract the insects they love to catch. Microbats can often be spotted swooping insects around park lights.

But they don't like:

  • being disturbed, especially when roosting in winter. They are very slow to "wake up" and easy prey to cats if the roost is disturbed. Disturbance, and subsequent harm, is the main reason microbats come into care.

Be a Microbat buddy

Try to:

  • build a special roosting box that can offer your microbat buddies a hangout for daytime naps or even a safe place to sleep through winter. Click here to find out how.
  • look for piles of insect "bits" on the ground to see if you have any microbats controlling insects in your neighbourhood. Microbats use their tail or wings to catch large insects which they carry to their favourite feeding site.


  • handling microbats. If you find a microbat that you think may need assistance - call your local wildlife rescue service for advice.
  • using electric insect zappers as they don't just kill the bad insects, they also kill the beneficial insects and remove the food for local microbats.

Some other interesting Microbat facts:

  • Microbats see with their ears rather than their eyes. They produce a sound and 'listen' for it as it bounces back from surrounding objects. The time the sound takes to travel back to them tells the bat how close the object is. As the sound bounces off the ground, trees, rocks and houses, the bat 'sees' a three dimensional image of its surroundings. The flutter of a tiny moth against a still leaf does not escape the microbat, and leads it to a tasty snack.
  • When cruising, microbats emit about 10 pulses per second. When an insect is detected the pulses go up to over 100 per second.
  • Females may fly hundreds of kilometres to special maternity sites to raise their babies.