Home range, activity and distribution patterns of a temperate rocky-reef ®sh, Cheilodactylus fuscus

Red morwong (Cheilodactylus fuscus; Cheilodactylidae: Perciformes), are large temperate rocky reef ®sh that are patchily distributed in local aggregations of 3 to >100 ®sh. The home ranges and aggregating behaviour of red morwong were investigated using external tags (n ˆ 114, over 35 mo) and ultrasonic transmitters (n ˆ 9 over 20 d) at coastal and estuarine sites in southeast Australia. Adult red morwong had a mean home range during the day of 1865 m (SE ˆ 268). Night movement, determined by ultrasonic telemetry, indicated a signi®cantly greater mean home range of 3639 m (SE ˆ 416). Home range did not di€er signi®cantly with size or sex. Fish movements were greatest and aggregation sizes varied most during the non-reproductive mid-summer period. Tagged ®sh (N ˆ 20) displaced 200 to 900 m returned in 1 to 3 d to the point of capture, often traversing open sand habitat and other aggregations. During the day, ®sh were commonly found on bouldered habitat. During the night, these site-speci®c aggregations fragmented as ®sh dispersed over a variety of substrata, with crepuscular peaks in activity. Therefore, estimates of habitat-speci®city and feeding patterns collected only by day may give misleading results.