ABSTRACT
In addition to serve in studying growth and mortality of a population, tagging experiments followed by a series of recaptures are useful in following animal movements. Tagging experiments have been conducted on seven aspidochirotid holothurians from different lagoonal and reefal habitats of the lagoon of New Caledonia. On reef-flats, where high density populations are observed, the position of tagged individuals was located inside quadrats marked out by pegs and orientated. In deeper stations, where population densities are usually lower, the quadrats were larger and were not delimited with precision. Recaptures were generally made each three months. Recapture rates are highly variable, depending on the species and their progressive decline is mostly due to the loss of tags. Concerning the reef-flats species Actinopyga echinites and A. mauritiana, the movements of some tagged individuals were followed over one year. Their mobility was rather limited as many individuals were found within the inner quadrat after six months. The average direction of movement has been determined for these two species. It is apparently random for A. echinites and orientated towards the reef crest for A. mauritiana.
