Selective feeding behaviour in some aspidochirotid holothurians (Echinodermata: Holothuroidea) at Stidia, Mostaganem Province, Algeria

Abstract

A study of the feeding behaviour of some aspidochirotid holothurian species inhabiting the Posidonia oceanica meadows near Stidia in Mostaganem Province, Algeria, was carried out in order to assess their ability to selectively feed. This study is an assessment of the level of organic matter in sediments of the gut contents of these species, their faeces, and the sediment of their biotope. A granulometric analysis of the ingested particles by Holothuria(Roweothuria) poliand sediment particles of its biotope was also conducted as part of this study in order to estimate this species’ degree of feeding selectivity. The holothurians studied showed a selectivity for organic matter: H.(Platyperona) sanctoriis the most selective species, followed by H. (Panningothuria) forskali, H.(R.) poli and H.(Holothuria) tubulosa. This difference in selectivity may be related to their micro-distribution in the different habitats of the Posidoniameadows (“herbier sur matte”, “inter-matte”, “tombants de matte”). The fine and very fine fractions of the sediment are selected by H.(R.) poli, thereby confirming the “optimal foraging theory”.