I’m obsessed with deep sea sharks: their bioluminescent spots are just visible in the pitch black environment they live in

Most of these little-known but already endangered fish have never been seen alive in their natural habitat, but are under threat from bottom trawling and deep-sea mining

Three years ago I was running a research project from a bottom trawler off Namibia about deep-sea sharks - all of which live under enormous water pressure, close to the seafloor and are rarely seen by humans.

These sharks were being brought up in the trawler's nets. By the time they were brought to the surface, they had experienced such a dramatic change in pressure that they had undergone barotrauma, so they were internally damaged and unlikely to survive.