This is a small supplementary project that will inform other carp sampling related projects in the IA CRC.

Aims

This project will determine if there are differences between age at maturity and growth rates of carp between northern and southern catchments of the Murray-Darling Basin. Determining differences will be important for modelling and population dynamics, and will inform control strategies.

Progress

The field and tank components of this project have been completed. Twelve carp that had been marked with oxytetracyline (OTC) and released into lagoon sites near Goondiwindi were recaptured after 15 months at large and another 36 OTC marked adults and 40 OTC marked young of the year (YOY) were sacrificed after being held for 15 months in tanks. YOY carp were sacrificed monthly over this period to enable estimation of the timing of first check formation.

Next step

The ear bones (otoliths) of these fish will now be processed and preliminarily examined at the Queensland Southern Fisheries Centre, then sent to Vic DPI (experienced for carp ageing) for confirmation of ageing and timing of check formation.