About a quarter of all marine species live on coral reefs.

For scientists like us, the observation and monitoring of marine species can be challenging under the best of circumstances.

All around the world the public seems to have realised that marine species are wildlife that need managing.

So far, 244,000 marine species have been officially named, but the scientists believe there are many hundreds of thousands more in the depths.

Many marine species, especially whales, use hearing as their primary sense, in an environment through which sound travels vast distances.