mesopelagic zone

[mĕz′ə-pə-lăj′ĭk]

A layer of the oceanic zone lying beneath the epipelagic zone and above the bathypelagic zone, at depths generally between 200 and 1,000 m (656 and 3,280 ft). The mesopelagic zone receives very little sunlight and is home to many bioluminescent organisms. Because food is scarce in this region, most mesopelagic organisms migrate to the surface to feed at night or live off the falling detritus from the epipelagic ecosystem.