We’ve started our surveys in the Turks and Caicos Islands, located on the eastern end of the Bahamas banks. Turks and Caicos are made up of the islands that line two of these banks. The larger bank, Caicos, is lined by six main islands: Providenciales, North, South, East, West and Middle Caicos. It spans about 60 nautical miles at its widest but only has a maximum depth of 5-6 metres in a few locations. Other shallower areas along the bank are tidal dependent and only experienced locals attempt crossing these areas. These banks are not homogenous but actually consist of an array of habitats for marine organisms. Mangroves provide refuge for juvenile fish, while green turtles forage along the sea grass beds, and even the bare sand is foraging ground for conchs that graze on the algae.
With the help of a local boat driver, the team can easily get to our fringing reefs, located on the oceanic side of these islands, by navigating through the banks rather than ploughing through open water. The smooth ride is something both the team and the equipment can definitely get used to!
The coral reefs of Caicos have a reputation for being fairly healthy as there isn't a big impact from overfishing, and the area was less affected by the 2005 mass coral-bleaching event compared to other Caribbean areas. The team was very excited to see how these reefs compared to other sites in the Caribbean.
We found the structure of the coral reefs was the similar to the Bahamas, where much of the windward facing reefs had very little hard coral structure, which was limited to growing only on the rock spurs projecting out from the sandy substrate. On the leeward side, patch reefs tend to extend down to 15 metres, where the reef crests form into a solid wall.
However, although there was higher coral cover than in the Bahamas there was also a fair amount of coral disease including a lot of Montastrea colonies infected by yellow blotch disease. As its name suggests, a pale yellow discolouration develops on the coral tissue that eventually progresses to the death of the tissue. Additionally, many of the sea fans were afflicted by a disease called Aspergillosis. This is a fungus that causes lesion in the tissue of the soft coral and changes neighbouring tissue a deep purple. On top of this, many of the sea fans were also infested by flamingo tongues.
The team will be making our way to South Caicos in the morning, where we will be surveying coral reefs sites that have been monitored by the School Field studies over the last twenty years. It will be good to be able to compare our findings to previous surveys.