Movement patterns, spatial distribution and depth preference by individual whitefish, Coregonus lavaretus in a small artificial lake

摘要

Using manual acoustic tracking our study quantified (1) the spatial distribution (2) the movement patterns and (3) the depth preference of adult whitefish, Coregonus lavaretus in it small artificial lake of eastern Belgium were the species was introduced in 1978 for recreational fishing. From June to October 2004, n=6 C. lavaretus (LF 285-519 mm) were tracked (pingers and depth sensor transmitters) from a small boat over periods ranging from 98 to 108 days in Robertville Lake (elevation: 490 m; area: 63 ha max. depth: 47 in). Whitefish were consistently mobile but showed quite variable lake use patterns. Two individuals traveled the entire length and breadth of the lake, whereas others remained in movement in the deep zone in the middle part of the lake or near the retaining darn wall. Whitefish occupied positions in the water column ranging front 2.6 to 27.0 m (mean 12.7 +/- 5.6 m) that varied depending on individuals. This first study on individual whitefish behaviour provides a better understanding of the behavioural ecology of the species in small artificial lake.