Discovered in the deep: a ‘night-time migration’ of marine life – in pictures

These images were taken by underwater photographer Robert Stansfield, from Southampton, UK, on a blackwater dive in the open ocean surround the island of Cozumel, Mexico.

The blackwater dives never fail to amaze me with the crazy alien-like life forms that drift past out in the open ocean, well away from a reef,' says Robert. The idea is to see the largest biomass migration on the planet. Every night a huge volume of life migrates up from the mesopelagic zone up to the epipelagic. This night-time migration gives us the opportunity to see life at the surface that normally lives well beyond recreational diving depths.'

This article was amended on 23 February 2023. An earlier version misspelled crab megalopa as megalopia".