Sampling techniques included scuba, trawl, dredges, and suction samplers at depths of 19 to 100 meters. This data can be compared to a 1960 survey to illuminate possible changes brought on by oil and gas exploration on the outer continental shelf. Subsets of the sponges collected in 1980 have been identified by examination of their spicules.
Spicules are silicate or calcium carbonate structures, which support the soft tissues of sponges.
The size and shape of the spicule is diagnostic of the sponge species. Previous species identification was performed by visual examination of the entire sponge. From these results, species abundance and distribution maps could be constructed. Our work suggests that species identification through examination of the number of species within a lot provided an unrealistic view of sponge diversity and population. Continuing efforts at species identification using spicule size and shape should provide a clearer picture of sponge diversity in this important ecosystem.