Most probably, but at those depths they should be relying on other "sensors" to survive as there is not that much light to illuminate their surroundings anyway.

Most probably, but at those depths they should be relying on other "sensors" to survive as there is not that much light to illuminate their surroundings anyway. Edit: And then there's the anglerfish with its bioluminescent lure on its head: https://video.nationalgeographic.com/video/00000144-0a34-d3cb-a96c-7b3d3ad40000 https://video.nationalgeographic.com/video/00000144-0a34-d3c... The seas are home to such fascinating creatures ...