Scavengers are animals who eat off already dead animals. Typical scavengers are foxes, bears and vultures, and invertebrates like flies, snails and worms. Some of these scavengers are also predators, who kill animals too. Scavengers complement the role of the decomposers in the decomposition of dead larger animals. When such an animal dies, the scavengers are first on the scene and they do most of the work of decomposition.
In the sea, there are many scavengers you likely are not familiar with. See some of them in this time-lapse film. Source: BBC