THE NSW Department of Primary Industries has relocated almost 80 stressed fish including Murray cod and golden and silver perch from the Lower Darling River downstream of the Menindee township.
Fisheries officers rescued and relocated 16 Murray cod, 15 silver perch and eight golden perch from a spillway pool that was soon to become disconnected from the river when flows cease through Weir 32. All fish were relocated to a much larger pool downstream of the weir that includes an aerator and water quality is more favourable. DPI Fisheries staff also carried out inspections of disconnected pools further downstream during the day to determine if there are any stressed fish.
An additional 20 silver perch and 20 golden perch were removed and taken to Narrandera Fisheries Centre to be utilised as broodstock for future restocking efforts into the Lower Darling when conditions improve. This rescue follows the successful relocation of 20 Murray cod from the area the week before, which were captured and transferred to the Narrandera Fisheries Centre. These fish are in good health and adjusting to their new surroundings.
DPI Fisheries’ actions were in response to a requirement for WaterNSW to cease flows from Weir 32 via the fishway. DPI fisheries technicians travelled to the site to manage any potential adverse impacts on fish in the fishway and downstream when flows ceased. The department will continue to monitor conditions and respond accordingly.
A variety of methods have been used to rescue the fish, while minimising further stress on Murray cod and other native fish species. Any rescued fish requiring relocation over large distances will travel by road in the DPI Fisheries fish stocking truck, which is aerated and temperature monitored. Relocating fish is generally not the preferred response because of the additional pressure it places on already-stressed fish, however the unique circumstances during these dry and hot conditions have necessitated the use of a variety of management responses.
DPI is continuing to monitor water quality and is finalising an assessment of temporary aerators placed within the Darling River. Aerators can provide localised water quality benefits and refuge for fish.