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Which marine animals migrate from the aphotic zone to the photic zone at night?

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Diagram showing ocean zonation by depth and region, with labeled layers: littoral, sublittoral, bathyal, abyssal, and hadal along the seafloor, and epipelagic, mesopelagic, bathypelagic, and abyssalpelagic in open water. The littoral zone is at the high-tide mark. Vertical scale marks photic and aphotic zones from surface to 10,000 meters. — Marine ecosystem Zonation of the ocean. Note that in the littoral zone the water is at the high-tide mark.

Many marine organisms, including various types of plankton, fish, and squid, perform daily vertical migrations between the aphotic zone and the photic zone.12

This behavior is primarily a response to light levels. By remaining in the darkness of the aphotic zone during the day, these animals can avoid visually oriented predators. After sunset, they ascend to the surface waters, where food is more abundant, allowing them to feed safely under the cover of darkness. They typically return to deeper, darker waters before dawn.1

While this migration is a widespread phenomenon, it is important to note that not all deep-sea animals participate in it. Some species, such as the tripod fish and certain sea cucumbers and brittle stars, remain in the aphotic zone throughout their entire lives.2