A demographic study of the water-rat (Hydromys chrysogaster) on the River Torrens in Adelaide, South Australia
C. M. Leigh A and W. G. Breed B CA Adelaide Medical School, Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA 5005, Australia.
B School of Biological Sciences, Faculty of Sciences, and Robinson Research Institute, The University of Adelaide, Adelaide, SA 5005, Australia.
C Corresponding author. Email: bill.breed@adelaide.edu.au
Australian Mammalogy 42(3) 277-282 https://doi.org/10.1071/AM19049
Submitted: 29 July 2019 Accepted: 8 October 2019 Published: 29 October 2019
Abstract
The population of water-rats (Hydromys chrysogaster) on the River Torrens in Adelaide was monitored over a three-year period. Initially, the population density was high but it became greatly reduced after the water level was lowered and did not recover again until over a year after the high water level had been restored. Males tended to have a larger home range than did females although they did not appear to exclude other individuals from their territory. Breeding generally took place in spring and summer although a few young appeared to be produced in most months of the year. This high population of water rats may, to some extent, be due to the abundance of the exotic fish species that occur in the River Torrens.
Additional keywords: rakali, territory, water level.
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