Often in construction projects which involve works within streams or dams, fish and other species like turtles are present and require removal to prevent mortalities due to becoming stranded or stressed with changes to their environment such as depletions in dissolved oxygen.
Catchment Solutions fisheries ecologists are suitably qualified to undertake these works under a Fish salvage permit, a general fisheries permit, and an animal ethics approval as required by Department of Agriculture and Fisheries. During the fish salvage the Department of Agriculture and Fisheries guidelines were followed as close as practically possible.
In total, 11 fish species and 1535 individuals were captured during the fish salvages. An astounding number of noxious fish such as tilapia, mosquito fish, and jaguar cichlids were captured which accounted for 68.5% of the individuals captured.
Native fish species captured and safely released included empire gudgeon, tarpon, spangled perch, eastern rainbowfish, and purple-spot gudgeon. Two eastern long-necked turtles were also captured and released alongside the native fish species.
Catchment Solutions Fisheries Ecologist, Matt Moore, shown here with a pest fish Tilapia.
A pump was used to gradually pump down the dam to allow access for seine netting. Due to the high amounts of ‘silty’ sediments, the dam was pumped to approximately 0.4 m deep to ensure safe access for persons partaking in the seine netting. Seine nets were dragged from the northern end of the dam to the south where a sump was excavated for the pump intake.
Workers scooped fish into aerated buckets so fish could be sorted. Noxious fish were in large numbers and placed in an ice slurry for humane euthanasia post capture. Native fish were sorted into insulated holding tubs with clean aerated water and transported to a location downstream in Janes Creek hourly, to limit stress. Following euthanisation, noxious fish species were buried in a location away from any waterways within the construction site. Other non-fish species (i.e., turtles) were released at Janes creek with the fish salvaged.