Effect of invasive tagging on the activity of Holothuria whitmaei [Echinodermata: Holothuroidea]:: A suitable mark-recapture method for short-term field studies of holothurian behaviour

Although mark-recapture techniques traditionally have been used to obtain ecological data, tagging of soft-bodied holothurians has proven difficult, and the degree to which invasive tags may confound the behaviour of holothurians remains unclear. In this study, diurnal patterns of activity were monitored in the commercial sea cucumber Holothuria whitmaei (black teatfish) after marking the tegument superficially with a number measuring 30x20mm (to a depth of <= 2mm). Rates of activity in marked specimens increased significantly in the initial hours following marking, and remained higher than those of unmarked control animals for up to 3 days following the procedure. These results suggest (a) that behaviour in holothurians may initially be compromised by marking the tegument and (b) that improved measures of activity may be obtained following a suitable recovery period. This is a useful finding given the need for improved knowledge of commercial holothurian biology, including diurnal and seasonal patterns of behaviour.