Diel vertical migration (DVM)

December 9, 2023

Species of the deep ocean may seem as strange as aliens from another planet but these creatures are products of the same biochemistry that impels other animals.
Driven by the need for food and to avoid predators, deep-sea marine animals – especially tiny free-floating zooplanktons – swim up to the surface at night.
The daily, synchronized movement of marine animals between the surface and deep layers of the open ocean is called diel vertical migration (DVM).
It’s also known as diurnal vertical migration.
The timing of this migration is tuned to the natural rhythms of sunrise and sunset.
This type of migration is the largest animal migration on the planet and is undertaken every single day by trillions of animals in every ocean.
It makes for a captivating display of nature’s ingenuity.
It is also a crucial player in the earth’s carbon cycle.
- Animals dwelling in the mesopelagic layer (layer that extends from 200 to 1,000 meters below the ocean’s surface) actively remove substantial amounts of carbon from the upper ocean as they feed on surface-dwelling plankton.
- When these organisms return to deeper waters, they carry the carbon with them.
- Even within the mesopelagic layer or twilight zone, some migratory animals become part of the food chain, passing on the carbon they have consumed to their predators.
- The carbon-rich waste produced by the predators then sinks to the ocean floor, where it remains trapped for millennia.