BIOT MPA Survey Expedition 2015 - Day 8 - Blenheim Reef

Today was the first day in the expedition where we visited an atoll without any land mass. Blenheim Reef is a completely submerged atoll to the east of the Salomon Atoll. As a result Elizabeth and myself decided to enter the water and see how things were looking in the marine environment in Chagos and how the Catlin Seaview Survey team got their work done.

On our dives we cruised the reefs to continue Elizabeth’s work. As usual the reefs were rich in fish and coral life.

Unusual on the first dive was a large bed of macroalgae below 25 meters stretching into the depths. This sort of plant life really gets to flourish in the waters of the Chagos archipelago as the prolific fish life tends to eat it before it establishes itself in such large tracts. A point that was illustrated later in the dive by a huge shoal of surgeonfish devouring the turf algae at a shallower depth.

Saw several heads of Chagos Brain coral. In amongst the reefs we saw several heads of Chagos Brain Coral – Ctenella Chagosensis. This coral is endemic to the archipelago and has a beautiful pattern of grooves decorating it’s surface.

A number of encounters reminded me of just how rich the marine life is here in Chagos. A beautiful porcelain crab on a carpet anemone with a couple of Chagos Anemonefish in attendance. An octopus that disappeared back into the reef when I approached. A large nurse shark that almost swam into us and shot off before I had the chance to get my camera out.

A great reintroduction to the underwater realm out here. There will be more opportunity as we head out over to Speaker’s Bank tomorrow and then South to the eastern Great Chagos Bank which is very little explored. A new place to be discovered!