Use of instream wood habitat by Trout Cod Maccullochella macquariensis (Cuvier) in the Murrumbidgee River

Abstract

Microhabitat use of instream wood habitat by Trout Cod Maccullochella macquariensis (Cuvier), a critically endangered species with a restricted distribution, was examined in the Murrumbidgee River in New South Wales, Australia. Habitat variables were scored or measured at 100 m intervals along the river or wherever Trout Cod were captured using electrofishing. The occurrence of Trout Cod was significantly dependent on the presence of instream woody habitat and 95% of samples where trout cod were caught were associated with the presence of woody habitat. Trout Cod were more likely to be found on simply-structured woody habitats, away from the river-bank and their abundance showed no relationship with water velocity. The low abundance of other fish species at the sampling sites suggests that the relationships demonstrated are not due to inter-species interactions. The results will assist with specific management actions to restore and protect populations of this endangered species.