The relationship between environmental conditions and activity of the giant barred frog (Mixophyes iteratus) on the Coomera River, south-east Queensland
Amelia J. Koch A C and Jean-Marc Hero BA School of Geography and Environmental Studies, University of Tasmania, Private Bag 78, Hobart, Tas. 7001, Australia.
B Centre for Innovative Conservation Strategies, School of Environment, Griffith University, Gold Coast campus, PMB 50 GCMC, Bundall, Qld 9726, Australia.
C Corresponding author. Email: ajkoch@utas.edu.au
Australian Journal of Zoology 55(2) 89-95 https://doi.org/10.1071/ZO06017
Submitted: 15 February 2006 Accepted: 23 April 2007 Published: 28 May 2007
Abstract
Determining the population density of ectotherms is often confounded by individual activity levels, which are highly dependent on ambient climatic conditions. In this study we used radio-telemetry and streamside surveys to examine the influence of local climatic conditions on individual activity levels (detectability) and streamside density of a population of endangered giant barred frog (Mixophyes iteratus) along the Coomera river in south-east Queensland. Temperature was the most important climatic variable influencing the behaviour and hence detectability of M. iteratus. The results indicated that males bury under the leaf litter during cold conditions (<18°C) so fewer were detected during surveys. Although females were also found to bury under the leaf litter in cold weather, no significant relationship between exposure and streamside density was detected. This is likely to be due to the lower number of females detected during surveys. The streamside density of juveniles was significantly related to temperature and rainfall, but little of the variance in the data was explained by climatic conditions, despite greater numbers of juveniles being found than adults. These results indicate that, for increased efficiency, surveys of Mixophyes iteratus should be undertaken when temperatures exceed 18°C.
Additional keywords: amphibian, climate, detectability, environmental variables, frogs, radio-tracking, surveys.
Acknowledgements
Many thanks to the volunteers who assisted in the field work for this project. In particular, Matt Fossey, Simon Hodgkison, Luke Shoo and Andrew Melville. Thanks also to Clare Morrison, Luke Shoo and Andrew Melville for advice throughout the study.
Berven, K. A. (1990). Factors affecting population fluctuations in larval and adult stages of the wood frog (Rana sylvatica). Ecology 71, 1599–1608.
| Crossref | GoogleScholarGoogle Scholar |
Crump, M. L. , and Pounds, J. A. (1989). Temporal variation in the dispersion of a tropical anuran. Copeia 1989, 209–211.
| Crossref | GoogleScholarGoogle Scholar |
Fukuyama, K. , and Kusano, T. (1992). Factors affecting breeding activity in a stream-breeding frog, Buergeria buergeri. Journal of Herpetology 26, 88–91.
| Crossref | GoogleScholarGoogle Scholar |
Hodgkison, S. , and Hero, J. M. (2001). Daily behaviour and microhabitat use of the waterfall frog, Litoria nannotis in Tully gorge, eastern Australia. Journal of Herpetology 35, 116–120.
| Crossref | GoogleScholarGoogle Scholar |
Holenweg, A. K. , and Reyer, H. U. (2000). Hibernation behaviour of Rana lessonae and R. esculenta in their natural habitat. Oecologia 123, 41–47.
| Crossref | GoogleScholarGoogle Scholar |
Magnusson, W. E. , Lima, A. P. , Hero, J. M. , and Araujo, M. C. (1999). The rise and fall of a population of Hyla boans: Reproduction in a neotropical gladiator frog. Journal of Herpetology 33, 647–656.
| Crossref | GoogleScholarGoogle Scholar |
Ovaska, K. (1991). Reproductive phenology, population structure and habitat use of the frog Eleutherodactylus johnstonei in Barbados, West Indies. Journal of Herpetology 25, 424–430.
| Crossref | GoogleScholarGoogle Scholar |
Salvador, A. , and Carrascal, L. M. (1990). Reproductive phenology and temporal patterns of mate access in Mediterranean anurans. Journal of Herpetology 24, 438–445.
| Crossref | GoogleScholarGoogle Scholar |
Stewart, M. M. (1995). Climate driven population fluctuations in rain forest frogs. Journal of Herpetology 29, 437–446.
| Crossref | GoogleScholarGoogle Scholar |
Woolbright, L. L. (1985). Patterns of nocturnal movement and calling by the tropical frog Eleutherodactylus coqui. Herpetologica 41, 1–9.