Translator Disclaimer
17 August 2017 Effect of flow on platypus (Ornithorhynchus anatinus) reproduction and related population processes in the upper Shoalhaven River
Author Affiliations +
Abstract
The platypus (Ornithorhynchus anatinus) occupies a wide range of aquatic habitats, feeding mainly on benthic macroinvertebrates. In this study, we investigated how flow affects platypus reproduction in the unregulated upper Shoalhaven River in rural New South Wales. In a mainly dry period, the population occurred at relatively high density (12.4 animals km–1) and was strongly female-biased (84% of resident animals); mean annual loss and recruitment of resident females were respectively estimated to be 12% and 14%. Percentage lactation was 17–71% (n = 23 years), and annual reproductive success (defined as the mean number of juveniles captured per adult/subadult female from February to April) varied from 0 to 1.5 juveniles female–1 (n = 21 years). A significant positive linear relationship was evident between percentage lactation and antecedent discharge in the five months before breeding (March–July) and a positive curvilinear relationship was evident between percentage lactation and mean litter size. Conversely, reproductive success was compromised by high poststorm discharge in the period when juveniles are confined to a nesting burrow, especially from late November to early January. The relationships identified in our study between flow and reproduction also appear to apply to platypus populations occupying urban streams in Victoria, suggesting that they may be widely relevant to this species.
© CSIRO 2017
M. Serena and T. R. Grant "Effect of flow on platypus (Ornithorhynchus anatinus) reproduction and related population processes in the upper Shoalhaven River," Australian Journal of Zoology 65(2), (17 August 2017). https://doi.org/10.1071/ZO17025
Received: 30 April 2017; Accepted: 1 July 2017; Published: 17 August 2017
JOURNAL ARTICLE
10 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top