A bat colony on the Central Coast of NSW is showing how ecosystem health can be responsibly managed and protected in working forests managed for timber production.

Local Forestry Corporation staff discovered Australia’s largest known roost of Eastern Horseshoe Bats in a previously unmapped cave in a remote area of the Ourimbah State Forest during field surveys in 1996.

After the colony was recorded and mapped and harvest plans were modified to ensure a large area around the roost would be left undisturbed during forestry operations, an annual population survey was implemented to keep track of the colony.

Each year, a small expedition treks up a steep hill to the remote location transporting two car batteries for power, a series of infra-red beam units and a data-logger, which are set up to count each bat that flies out of the cave at dusk over four consecutive nights. Fifteen years on, the data shows the colony is thriving, with the population size fluctuating around the 10,000 mark, making it possibly one of the largest Eastern Horseshoe bat populations in Australia.

Senior ecologist Chris Slade said healthy bat populations are important to forest ecosystem health because bats keep insect populations in check and prevent them from proliferating and damaging trees and other flora.

“This result is good news for biodiversity and for the forest and is a textbook example of how appropriate planning and sound environmental practices ensure ecologically important species can and do continue to thrive in working forests.”