ABSTRACT
Holothuroids can be divided by their feeding habits more or less into two principal groups, suspension feeders or deposit feeders. The environmental effect of the feeding activity by holothuroids will differ according to the group to which they belong. In general, it seems that chemical action on a calcareous sediment passing through the digestive tract of deposit feeding holothuroids is very weak. On the whole, environmental effects of feeding activities of holothuroids act mainly on the faunal composition of the surrounding substratum. The biological effect of deposit feeding holothuroids involves amensalism as defined by Rhoads and Young: inhibition by one trophic group on any-other trophic group. Deposit feeding holothuroids have direct and indirect effects on meiofauna and macrofauna. The role of suspension feeding holothuroids in removing material from the water column and transferring it to the bottom community through incorporation into their body components has not been considered.
