An apex predator, also known as an alpha predator or top predator, is a predator residing at the top of a food chain upon which no other creatures prey.[n 1] Apex predators are usually defined in terms of trophic dynamics, meaning that they occupy the highest trophic levels and serve as keystone species, vital to their ecosystems. One study of marine food webs defined apex predators as those feeding at trophic levels above four. The apex predator concept is commonly applied in wildlife managemen