Over the past decade, platypus populations in the Werribee River have been under threat from a variety of environmental and anthropogenic disturbances including the long-term drought experienced throughout south-eastern Australia, extraction of water for urban and agricultural use, fragmentation of populations by weirs, habitat degradation, litter, and predation.
As a result we have seen a significant decline in platypus abundance since surveys were first conducted in 1998.
Surveys during recent years indicate platypus numbers in Werribee are quite low with none of the previous five surveys catching more than one platypus and one survey in October 2010 resulting in no platypuses for the first time.
In March, cesar ‘s Wildlife Ecology team conducted a platypus survey of the Werribee River from Princes Freeway to the Southern Diversion weir as part of Melbourne Water’s Urban Platypus Program.
After a long night of checking nets and repairing holes caused by water rats, we were finally rewarded with two captures around dawn – an adult female and a juvenile male.
Although still low numbers, it is the highest captures recorded for a single survey since mid 2009.
Most encouraging is the presence of a juvenile, the first evidence of successful breeding occurring in the area for several years.
This provides some indication that the platypus population in Werribee may be starting to recover after years of decline.