Question: what do you actually research underwater?

Sean Clement answered on 24 Jun 2011:

Short answer: Coral Reefs!

Long answer: My work in Madagascar was based mainly around research into the Coral Reefs of the area and how healthy they are and how they’ve changed over the years that we’ve been conducting research on them. How do we do this? Well, me survey several different variables that each fill in a little bit of the picture behind how each reef is getting on.

1. Benthic coverage. Benthic means living on or attached to the seabed, meaning Coral, algae, and other sessile (meaning they don’t move) invertebrates. By measuring this, we can tell how much of each type of organism is present on each reef. Lots of Hard Coral means that it’s a ‘healthy’ reef in most cases. Lot’s of Seaweed means that the Coral has all died away and the reef has now been overrun in whats known as Algal encroachment. We also survey the number of juvenile corals on a reef in an attempt to determine what coral growth might be like in the future…

2. Fish populations. How many fish there are, what types of fish there are and how big they are! Its that simple, and it gives us an idea of how much a reef is suffering from fishing pressure. If there are lots of small fish and very few big one, then there’s probably too much fishing taking place on that reef. If there are very few herbivorous fish, then there aren’t many fish able to keep algal encroachment in check (think of what would happen to a a garden if you suddenly removed all the gardeners…)

We do other survey occasionally, like measuring Coral Bleaching but, for the most part, we’re collecting data on the above as these are the best indicators to use in terms of Coral Reef health!