Beauty is in the eye of the bat-holder for Victoria’s tiniest bug controllers

31 January, 2012

Victoria’s tiniest bats are enjoying a fantastic feast with the warm wet weather’s boom in insect numbers.

And while you may not be aware of it, these little microbats are actually playing an important role in controlling bug numbers.

Bat ecologist from the Department of Sustainability and Environment’s (DSE) Arthur Rylah Institute Micaela Jemison said it is often their small size that has them mistaken for large moths or small birds such as swallows.

“People may see microbats around Victoria more than they think. There is possibly up to 21 species of microbat within Victoria and many of them can be seen around dusk or later in the night zig-zagging around catching insects,” Ms Jemison said.

“Each of these tiny bug controllers can munch through as much as three-quarters of its body weight in insects a night. Although they may be small, their sheer numbers and ravenous appetite for insects means that they play a really important role in keeping our bug populations in check.”

Microbats are seldom seen up close by Victorians, with most only getting a glimpse of a fast moving blur at best, but an up-close look would reveal the adaptations these animals have made for their unusual way of life.

“While our microbats are unlikely to grace the pages of a magazine spread, their facial structure is perfect for navigation and insect catching,” Ms Jemison said.

“For example, the enormous ears and leaf shape nose of horseshoe bats (Rhinolophus sp.) are specialisations for the way they catch their prey.

“To navigate and find insects, they emit an ultrasonic call through their nostrils and the leaf shape of their nose is thought to focus this sound.”

See some pictures of our microbats up close.

Microbat facts:

• The smallest of the Victorian microbats is the Little Forest Bat (Vespadelus vulturnus) which can weigh as little as 3 grams (less than the weight of a 10 c piece).

• Four of the 21 species of microbat found around Victoria are listed as threatened under the Flora and Fauna Guarantee Act 1988.

• DSE scientists are undertaking research to further understand the threats to these species as part of the Victorian Government’s responsibility to protect threatened species.

• All microbats send out ultrasonic calls through their nostrils or mouth to navigate and hunt their prey.

• Microbats are active at night - during the day they mostly roost in the hollows of live and dead trees.

Scientists from the Arthur Rylah Institute are still discovering new ways microbats benefit the environment through their research around Victoria. Watch a video on how they study microbats.