Coastal sheathtail bat

Common name: coastal sheathtail bat

Scientific name: Taphozous australis

Family: Emballonuridae

Conservation status: This species is listed as Near Threatened in Queensland (Nature Conservation Act 1992).

Description

This large insectivorous bat has a head and body length of up to 90mm and a tail of between 20-30mm. Its most obvious diagnostic feature is the projection of the tail through the upper surface of the tail membrane. The coastal sheathtail bat also folds its wing tips above the remainder of the wing when at rest.

The fur colour is variable, being grey to brown with slightly lighter belly fur, and an olive tinge to the lower abdomen. The tail membrane is furred up to the point where the tail projects through it. A pouch formed from skin over the throat is present in males, but is smaller and less distinct in females. Another pouch is present underneath the wing near the wrist in both sexes.

Habitat and distribution

The coastal sheathtail bat forages within about one kilometre of the ocean, in habitat including sand dune scrub, mangroves, melaleuca swamps, coastal heathlands, open eucalypt forest, and grasslands. Coastal sheathtail bats that roost on coastal islands off Cape York Peninsula have been observed to fly to the mainland to forage.

The coastal sheathtail bat is distributed in a thin band along the north-east Queensland coast from Shoalwater Bay to Cape York, extending no more than a few kilometres inland. This species is believed to be unevenly distributed throughout its range, due to its reliance on coastal roosts.

Life history and behaviour

Nocturnally active, this species forages just above the canopy, capturing prey in flight. They have fast direct flight with high agility. During the day they roost in sea caves, mines, concrete bunkers or rock fissures where temperatures are between 26.5–28ºC and humidity 84-92 per cent. Generally individual bats roost between 10-150cm apart, but in winter they can form clusters of two to five bats.

Breeding starts in April and stops in September. Young are born from September to November and are large by January.

Threatening processes

A decline in numbers in the southernmost colony at Cape Hillsborough has been attributed to increased human visitation. It is also suspected that alteration of foraging habitat through sand mining and coastal development threatens the species.

Recovery actions

• Protect roosts from further disturbance, particularly roosts determined to be maternity sites.
• Determine foraging habitat preferences.
• Establish a long term monitoring program to detect any population changes and determine population viability.

Relevant information

Churchill, S. 2009. Australian Bats (second edition), Allen and Unwin, Sydney.

Curtis LK, Dennis AJ, McDonald KR, Kyne PM, and Debus SJS. 2012. Queensland’s Threatened Animals, CSIRO, Victoria, Australia

Duncan A, Baker GB and Montgomery N (Eds.). 1999. The Action Plan for Australian Bats. Environment Australia, Canberra.