The Murray-Darling Basin Plan is a major investment in water reform with up to $12 billion committed to achieve environmental outcomes in the waterways across the MDB. One of the objectives of Basin Plan is to protect and restore native fish populations through water management. One way that we can assess whether this objective has been met is to identify whether there is an increased breeding response from fish through the detection of recruits.
Concurrent to Basin Plan implementation, some Basin States have native fish stocking programs that aim to enhance numbers of native fish. Currently over 4.6 million freshwater native fish (predominantly Murray Cod and Golden Perch, but also including Macquarie Perch, Trout Cod, Silver Perch and Freshwater Catfish) from government and private fish hatcheries are stocked annually in Basin waterways and impoundments. The stocking of native fish therefore represents a large confounding factor for Basin Plan monitoring and evaluation activities that are designed to assess fish recruitment.
NSW DPI, along with its Murray-Darling Basin jurisdictional partners is leading a project to identify stocked fish from wild fish using genetic parentage analysis (FishGen). A fin-clip library of broodstock from across the MDB is currently being assembled to enable a stocked fish to be identified with 99.9% confidence. The advantage that this method has over traditional calcein marking is that stocked fish do not need to be physically marked and wild-caught fish do not need to be sacrificed to identify a mark. In order for this program to be successful, all broodfish will need to have a fin-clip collected and sent to the FishGen program manager. In her presentation, Meaghan will discuss the progress of the program to date, and will explain the process to collecting a fin-clip sample suitable for DNA analysis.