Cruising along the muddy bottom we occasionally see isolated soft corals or sponges rising up from the benthos (bottom dwelling flora and fauna). In the absence of reef and rock, these animals provide the living space for many other smaller creatures. We sampled a hollow-stemmed gorgonian coral only eight inches tall that yielded over 100 individual crustaceans and represented at least seven species.
This is one of these gorgonians:
And this is a sampling of the crustaceans recovered from a single pink individual:
And what of the sea cucumbers from these deeper murky waters? We saw only two during our dive, but one was an encouraging find. It was Holothuria scabra, one of the two or three most heavily exploited and high-value species occurring in Madagascar (shown below). The typical price in Singapore for this species in 2003 was between US$40-56 USD/kilo dried, but it would not be unusual to get over $100/kilo in other markets.
Sea cucumbers have been heavily fished for centuries as part of a multi-million dollar food trade, with China as the principal center of consumption. Not surprisingly, many of the large sea cucumbers are rarer in Nosy Be than would be expected to occur naturally. Certainly this reflects how heavy they have been exploited, and unfortunately around the tropics this is the norm rather than the exception. The deeper murky waters where we found this animal are more inaccessible to fishermen, and the best hope for many of these highly sought after species may be their ability to thrive in habitats farthest from their reach.