Diel Activity of the Endangered Trout Cod (Maccullochella macquariensis) in the Murrumbidgee River

Abstract

Diel movements and habitat use of most of Australia's large freshwater fish fauna remain unknown, despite conservation efforts for many of the threatened species, including re-stocking and habitat protection and restoration. We used radio-telemetry to monitor diel movements of the endangered trout cod (Maccullochella macquariensis: Percichthyidae) in a re-stocked population in the Murrumbidgee River, New South Wales, Australia. Both manual tracking and continuous remote telemetry identified that trout cod activity peaked in periods of low light; with linear ranges for individuals varying from 6-272m. Trout cod had strong fidelity to outer river bends throughout diel periods and this has implications for targeted habitat rehabilitation efforts.