Many Deep Sea Fish, due to the darkness as well as biological makeup that is required to survive under the pressure of the conditions at this depth, are blind or rely on other senses in order to navigate and hunt.
Those that aren’t blind have large and sensitive eyes that can use bioluminescent light.
The habitat of Deep Sea Fish is found beneath the epipelegic zone. There is a unique phenomenon that happens at this depth called Marine Snow. Marine snow is a mix of sand, plankton, fecal matter, soot, and other forms of dust-like elements.
Hydrostatic pressure increases by 1 atmosphere for every 10m in depth. (*Wharton 2002, pp. 198.) Deep-sea organisms have the same pressure within their bodies as is exerted on them from the outside, so they are not crushed by the extreme pressure.
*Wharton, David (2002). Life at the Limits: Organisms in Extreme Environments. Cambridge: Cambridge University Press. p. 198. ISBN 9780521782128.
Most Deep Sea Fish prefer to wait and sit until food makes it way to them as opposed to active hunting.
They have a slow metabolism and will eat pretty much whatever comes along, such as Marine Snow.
Most of these deep dwelling creatures, especially those in the “Midnight Zone” are very sedentary, meaning they prefer not to output much energy and are likely to move minimally in the darkness.
Among the unique species of Deep Sea Fish you will find the following (but not limited to):
– Coelacanth and many more!