Waterfall frog
Litoria nannotis (Andersson,1916)
Queensland Legislative Status: Endangered
Endemicity: Queensland Endemic
Description: Size (SVL): males 31.6 - 52.1 mm, females 48.2 - 59 mm (McDonald & Alford 1999).
Weight: males 4.2 - 12 g, females 7.2 - 16 g (McDonald and Alford 1999).
A moderately large, robust species. The dorsal surface is slate, olive or dull brown colour, with irregular dark mottling. The ventral surface is white or cream in colour, often with brown on the throat. The axilla and groin are flesh coloured.
The skin is shagreened, finely granular, or with numerous small scattered warts above, granular below. The fingers have basal webbing, and the toes are fully webbed. The finger and toe discs are well developed. Males have a large prepollex, with black spiny nuptial pads and accessory spines on the chest, head, forearm and thighs. There is no vocal sac. The snout is bluntly rounded, and the tympanum is indistinct (Cogger 2000, Liem 1974).
Call: The call has been described as a repeated "crawk crawk crawk" or a gentle, popping, slow growl-like sound that is difficult to hear above the sound of flowing water (McDonald 1992, Richards 1993).
Tadpoles: The tadpoles are adapted for fast flowing stream conditions with suctorial mouth, muscular tail, narrow tail fins and ventro-lateral spiracle (Liem 1974). The body colour is grey or olive-green with dark abdomen, yellowish tail, and numerous diffuse dark-brown blotches across the tail muscle and fins (Richards 1992). The oral disc is surrounded by marginal and submarginal papillae, and has two anterior tooth rows, and three posterior (Liem 1974).
Reproduction: Gravid females are encountered year round, as are males with nuptial pads (McDonald and Martin unpubl. data). Large (2.7-3.4mm diameter) unpigmented eggs are layed as a gelatinous clump under rocks in streams (Liem 1974). The tadpoles graze on algal-covered rocks in fast flowing stream conditions.
Habitat: Litoria nannotis inhabits fast-flowing streams around waterfalls and cascades in rainforest from 80-1300m (McDonald 1992). They are generally found on boulders beside or behind waterfalls and cascades, but may be perched on trees or litter beside streams in moist conditions (Liem 1974) Tadpoles are found predominantly in fast flowing sections of the stream, attached to rocks (Richards 1992).
Distribution: Formerly occurred throughout the Wet Tropics between Paluma, north of Townsville and Mungumby Creek, 30km south of Cooktown. Significant population declines in upland populations have occurred since 1990. Litoria nannotis is now absent from most upland sites although since 1997 three sites above escarpments have been recolonised (McDonald and Alford 1999) although no tadpoles have been located.
Latitude: Between15&186; 42' and 19&186; 01';
Longitude: Between 145&186; 0' and 146&186; 16'.
National Parks: Cedar Bay, Daintree, Davies Creek, Crater Lakes, Mt Hypipamee, Barron Falls, Wooroonooran, Millstream, Tully Falls, Lumholtz, Paluma Range.
Threatening Processes: Suspected Threats: The causes of the decline remain unknown, Richards et al (1993) found no obvious evidence that drought, floods, habitat destruction or pollution by pesticides, inorganic ions or heavy metals were responsible for the population declines. Current research is examining the possibility that a disease may have caused the decline of this species (Berger et. al. 1999). Information on disease investigations and management can be located at http://www.jcu.edu.au/school/phtm/PHTM/frogs/ampdis.htm
Status: Litoria nannotis is one of seven species of frogs occurring in the upland rainforest streams which have undergone substantial population declines in north-eastern Queensland (Richards et al 1993). Since 1990 population declines or local extinctions have been noted at upland sites throughout the Wet Tropics Biogeographical Region. Litoria nannotis is now absent from most upland sites.
Management Recommendations: Draft Recovery Plan 1995 (Martin and McDonald 1995).
- Monitor historical localities to detect recovery.
- Investigate disease in preserved animals and species occupying similar habitat.
- Develop and refine husbandry techniques for rainforest stream dwelling frogs.
- Continue studies on the autecology on this species.
- Train park staff and community volunteers in identification of this species.
- Implement monitoring by park staff of select locations within the national park estate where L. nannotis formerly occurred.
References:
Berger, L., Speare, R, and Hyatt, A. 1999. Chytrid fungi and Amphibian declines: Overview, Implications and Future Directions. Pp23-33. In Campbell, A (ed), 'Declines and Disappearances of Australian frogs'.(Environment Australia, Department of the Environment and Heritage: Canberra). 234 pp.
Cogger, H.G. 2000. Reptiles and Amphibians of Australia. Reed New Holland, Sydney.
Ingram, G.J. and McDonald, K.R. 1993. An update on the decline of Queensland's frogs. Pp 297-303. In Lunney, D. and Ayers, D. (eds), 'Herpetology in Australia. A diverse discipline'. (Royal Zoological Society of New South Wales: Mosman). 414pp.
Liem, D.S. 1974. A review of the Litoria nannotis species group and a description of a new species of Litoria from north-east Queensland, Australia. Memoirs of the Queensland Museum. 17(1): 151-168.
Martin, W.E. and McDonald, K.R. 1995. Draft Recovery Plan for the Threatened Stream-dwelling Frogs of the Wet Tropics. Qld Department of Environment and Heritage, Brisbane.
McDonald, K.R. 1992. Distribution patterns and conservation status of north Queensland rainforest frogs. Conservation Technical Report 1., Queensland Department of Environment and Heritage, Brisbane.
McDonald, K.R., and Alford, R.A. 1999. A Review of Declining Frogs in Northern Queensland. Pp14-22. In Campbell, A (ed), 'Declines and Disappearances of Australian frogs'.(Environment Australia, Department of the Environment and Heritage: Canberra). 234 pp.
Richards, S.J. 1992. The tadpole of the Australian frog Litoria nyakalensis (Anura, Hylidae), and a key to the torrent tadpoles of northern Queensland. Alytes 10(3): 99-103.
Richards, S.J. 1993. A guide to the identification of declining frogs and their tadpoles in the Wet Tropics Biogeographic Region, Queensland. Unpublished Report QDEH
Richards, S.J., McDonald, K.R., Alford, R.A. 1993. Declines in populations of Australia's endemic tropical rainforest frogs. Pacific Conservation Biology 1:66-77.
Last updated: 30 August 2005