NOAA explorers Caves in Bermuda

The submerged entrance to Green Bay Cave (top center),
the longest known cave in Bermuda, is located at the end
of a small bay off Harrington Sound

The Green Bay Cave in Bermuda the longest known cave on the island and the target of a NOAA expedition running until September 30, 2009. Deep water marine caves represent one of the Earth's last largely unexplored frontiers of undiscovered fauna.

More than 150 limestone caves are known from the island of Bermuda, many of which have extensive, but relatively shallow submerged portions that connect to the sea via tidal springs along the coastline. These inland caves are inhabited by a number of diverse eyeless and colorless crustaceans and other invertebrates. Many of these organisms are “living fossils” and some are most closely related to deep-sea organisms, so a press release on NOAA’s ocean explorer website

The existence of ancient cave species and the fact that all known Bermuda caves were dry and air filled during Ice Age periods of lower sea level suggests that an alternate, now deep water cave habitat must have existed in Bermuda.

While previous investigations of marine caves have been limited to those within depths of up to 165 feet (50 meters), current research suggests that caves can occur at almost any depth within the sea. The geological history of Bermuda coupled with biological evidence indicates a strong possibility for the presence of deepwater caves near the island.



A series of expeditions will explore the seas surrounding Bermuda to search for deep water caves. NOAA plans to use multi-beam sonar to survey the area and create a high-resolution map of the sea floor. Investigators will look for cave entrances directly, as well as indirect indicators of the cave presence (schools of fish, plumes of “shimmering water”). After areas of interest have been identified, the team will use a remotely operated vehicle (ROV) to investigate sites.

Divers using mixed gas rebreathers will locate and investigate deep water caves. The goals of the exploration are to characterize the natural history of the Bermuda platform, discover deep water cave habitats, determine the origin and age of such caves, and observe and collect deep water cave fauna for comparison with species inhabiting Bermuda's shallow caves, so NOAA.

More information about the expedition can be found here.
Source: Global Adventures