What is one population in a saltwater ecosystem?

One population in a saltwater ecosystem is the Atlantic bluefin tuna (Thunnus thynnus). This species plays a crucial role as both a predator and prey, influencing the dynamics of marine food webs. Bluefin tuna are highly migratory, often traveling long distances between spawning and feeding grounds, which highlights their ecological significance in oceanic environments. Their populations are also of great economic importance due to their value in commercial fishing and sushi markets.