Norwegian oceanographers, together with their American colleagues from the Massachusetts Institute of Technology, talked about a predatory phenomenon in the Atlantic Ocean. Researchers watched a school of cod overtake a school of capelin and eat more than 10 million fish in a few hours. Many marine animal species gather for protection and migrate together, providing foraging opportunities for savvy predators.
But recently scientists have managed to determine the true scale of the movements of large fish populations with the help of new OAWRS (Ocean Acoustic Waveguide Remote Sensing) sonar devices, which allow monitoring large areas and collecting data on the behavior of individual individuals.
Researchers recorded how a capelin (Mallotus villosus) school of 23 million fish formed in Norway’s coastal waters at the height of the spawning season. Such a large number of capelin also attracted the attention of Atlantic cod (Gadus morhua), which joined the group and attacked the prey. As a result, more than 10 million fish were eaten in a few hours.
Despite the scale of the event, the total number of capelin, which number in the billions of individuals migrating in the waters of the northeastern part of the Atlantic Ocean, was not greatly affected. The researchers estimate that cod probably ate only 0.1% of the total population in the area.
Source: Port Altele
