Impact implantation of a transmitter on Sarpa salpa behaviour:: study with a computerized video tracking system

Two transmitter masses (2 and 6% of the fish's mass) were selected to examine the interference of tags with the behaviour of Sarpa salpa using a computerized video tracking system based on digital imaging techniques. The study demonstrated that light transmitters had no effect on the behavioural variables studied, and a substantial bias in behaviour is introduced if heavier (6%) tags are used. (c) 2005 The Fisheries Society of the British Isles.