Botanical and zoological collections may serve as archives for historical ecologi- cal research on the effects of global change and human impact on coral reef biota. Museum collections may harbour old specimens of reef-dwelling species that have become locally extinct. Such collections also help to determine whether early records of invasive species can be obtained from times when they were not yet recognized as such. A case study (2006) involving Saba Bank, Caribbean Netherlands (former Netherlands Antilles), suggests that the coral reef fauna here may have become impoverished when compared with data obtained during an earlier expedition in 1972. However, the 1972 sampling may have been incomplete, as it was performed by professional divers who were not trained taxonomists, whereas the collecting in 2006 was done by expe- rienced marine biologists who knew the taxa they were sampling. As Saba Bank has been under stress due to the anchoring of large vessels, and invasive species have been a potential threat as well, future studies are needed to obtain more insights into the changing reef biota of Saba Bank. Using this Saba Bank exam- ple, we want to address the importance of natural history collections as reser- voirs of valuable data relevant to coral reef biodiversity studies in a time of global change. As such, these collections are still underexplored and underexploited.
Land, J. van der
Abundant coral growth within the Saba Bank is restricted mainly to the two large windward reefs. These two reefs carry a very rich reef fauna.
The rest of the Bank only has a very small growth of corals due to several factors:
- Most of the food supply is probably filtered away by the large windward reefs.
- These reefs are located at a least favorable leeward position.
- These reefs are located at a considerably greater depth.
As in most other atoll lagoons, coral growth in the lagoon area is restricted to small patch reefs; the number of species is not significantly lower than on the reef, but the colonies are smaller in size and number.
The Saba Bank undoubtedly has a volcanic base but no information on this has been collected. This study did uncover some black sand, presumably of volcanic origin, on the southwestern part of the Bank. Geologists believe that a composite volcanic island is buried under the more recent formations.
Only the eastern and largest part of the Saba Bank can be called a living atoll with an open lagoon, while the western part is a bank with drowned fringing reefs. Whether the western part is included or not, the Saba Bank ranks among the largest atolls in the world.