Deep sea fish
Description of Niche
While the concept of deep sea fish may be a bit variable in terms of the depth they inhabit, it is usually understood that deep sea fishes are those living in the bathypelagic, abyssopelagic and demersal zone. Bathypelagic species, such as the angler fishes, inhabit the deeper part of the pelagic zone, lives from from 1,000 m down to around 4,000 m, while abyssopelagic species live from 4,000 m down to above the ocean floor. Demersal species occupy the bottom of the ocean floor and are divided into benthic and benthopelagic species. Benthic fishes are those that spend most of their time on the bottom such as the rays and flatfishes, while benthopelgic fishes are those that swim habitually near the ocean floor such as the squalid sharks (family Squalidae) and smoothheads (family Alepocephalidae).