Semon's leaf-nosed bat
Semon's leaf-nosed bat Photo: Michael Mathieson
Common name: Semon's leaf-nosed bat
Scientific name: Hipposideros semoni
Conservation status: This species is listed as Endangered, Queensland (Nature Conservation Act 1992) and nationally (Environment Protection and Biodiversity Conservation Act 1999). It is ranked as a medium priority under the Department of Environment and Heritage Protection Back on Track species prioritisation framework.
Description: The Semon’s leaf-nosed bat has a head and body length of about 40-50 mm with a wingspan of up to 320 mm and weighs 6-10 g. Semon's leaf-nosed bat can be distinguished from other leaf-nosed bats by its long, narrow ears with acute points. Its previous common name, the greater wart-nosed horseshoe bat, refers to the club-shaped projections on its nose-leaf; one in the middle and a smaller one on its posterior edge. These 'warts' are proportionately larger than in the northern leaf-nosed bat. The fur of the Semon’s leaf-nosed bat is long and a dark, smoky grey, and continues onto the wing membrane close to the body and along the lower front edge of the ears. It weighs 5.7-9.2 g.
Habitat and distribution
The full distribution of this species is still unknown. In Queensland it is known to occur along eastern Cape York Peninsula to Townsville, with the only confirmed records from Iron Range National Park to the Cooktown area. The southern limit of the species remains poorly known.
The Semon’s leaf-nosed bat forages in rainforest and savannah woodland.
Life history and behaviour
As with most micro bats, Semon's leaf-nosed bat is nocturnal. Little is known of their hunting behaviour other than they fly low, up to two metres above the ground, within vegetation and along narrow tracks. Its diet consists of moths, spiders and beetles.
The Semon’s leaf-nosed bat as been observed roosting alone and in small groups. They usually roost in tree hollows, rock fissures and caves. Pregnant females have been captured in late October, suggesting birthing in early November to a single young.
The known threats to Semon's leaf-nosed bat are the destruction of roosts, such as the destruction of one colony in a mine near Coen. It is suspected that roost disturbance, and habitat destruction or alteration, also affect this species.
There are no known predators, but it is possible predation may occur from ghost bats Macroderma gigas, which prey on other species of hipposiderids of similar size (Churchill 1998).
The national recovery plan cave-dwelling bats, Rhinolophus philippinensis, Hipposideros semoni and Taphozous troughtoni 2001-2005 recommends the following management actions for the conservation of the Semon’s leaf-nosed bat:
- Prevent further destruction and disturbance of roost sites from mining and other activities.
- Determine the southern limit of their distribution using predictive climatic models and targeted surveys.
- Conduct further research into its ecological requirements, particularly it’s roost site requirements.
de Oliveira, MC & Schulz, M. 1996. Echolocation and roost selection in Semon's leaf-nosed bat Hipposideros semoni, Memoirs of the Queensland Museum. 42:158.
Department of Sustainability, Environment, Water, Population and Communities (SEWPaC). 2013. Hipposideros semoni Semon’s leaf-nosed bat in the Species Profile and Threats Database. SEWPaC, Canberra.
Duncan A, Baker GB and Montgomery N. (Eds.). 1999. The Action Plan for Australian Bats. Environment Australia, Canberra.
Churchill S. 1998. Australian bats. New Holland, Sydney.
Thomson B, Pavey C and Reardon T. 2001. National recovery plan for cave-dwelling bats, Rhinolophus philippinensis, Hipposideros semoni and Taphozous troughtoni 2001-2005. Department of Environment, Water, Heritage and the Arts, Canberra.