We are on the East Chagos Bank now - a little explored system of coral atolls with no visible land whatsoever except for the small slivers of reef flat which rise just above the sea surface for an hour or two each day at low tide. Anchoring here is an odd sensation - we are surrounded by open ocean with absolutely no land in sight, even the reef is not visible for most of the time. Stopping mid-ocean out of sight of land is never usually done in a ship - perhaps only if the engines break down, so to be stopped, the engines off and surrounded by open ocean on all sides is a bit unnerving for the survey team.
But the Reef! What really strikes you working underwater in Chagos, and particularly here, is the fish life. On all the other reefs I’ve worked on we might see a coral trout or two on a dive, usually small and skittish they keep well away from boats and divers. But here, the coral trout are enormous; everywhere and they actually swim right over to see what we are! The reef literally teems with large fish, so much so that we joke that you have to push the fish out of the way just to see the corals! Maori wrasse, sweetlip, emperors, sharks all in abundance and totally unconcerned.
Yesterday a silvertip shark swam within a metre or two of us and then today a huge bull ray sat on the reef beside us while we worked and stubbornly refused to move no matter how close we got to it. We were forced to work around him while he looked on with a huge beady eye.
These marine encounters are extra-ordinary and we can only hypothesize that these animals are so bold because they aren’t used to humans. We imagine that this is what it must have been like on reefs before humans came along and speared, netted and hooked fish populations. It’s been quite a special experience both spiritually and scientifically for the team: we’re seeing what a virgin coral reef ecosystem can look like!