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6669022 
Journal Article 
Effect of flow on platypus (Ornithorhynchus anatinus) reproduction and related population processes in the upper Shoalhaven River 
Serena, M; Grant, TR; , 
2017 
Yes 
Australian Journal of Zoology
ISSN: 0004-959X
EISSN: 1446-5698 
CSIRO PUBLISHING 
CLAYTON 
65 
2 
130-139 
English 
WOS:000408652600007 
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. 
Zoology; life history strategy, MNA analysis, monotreme, platypus conservation,; population dynamics, river flow management; new-south-wales, body condition, fish, monotremata, behavior, regime,; food, sex, age, biodiversity