The mobile scavenger stage has a time span of 4-24 months, depending on the size of the whale carcass. This stage is characterised by the presence of larger necrophages where fish and crustaceans are particularly abundant (figure 2). During this stage 90% of the whale’s soft tissue is removed at a rate of 40-60kg d-1 (Smith and Baco, 2003).
Hagfish are typically the first species to arrive at the whale carcass in large numbers. It is estimated that hagfish Eptatretus deani, can be enticed to the carcass within a radius of up to 0.8km (Smith and Baco, 2003). The largest scavengers to take advantage of the whale carcass are sleeper sharks (Somniosus pacificus) which are up to 3.5m in length. Sleeper sharks feed aggressively, taking large bites of the carcass and are therefore responsible for more soft tissue removal and consumption than any other species. Lysianassid amphipods, rattail fish and crustaceans are also highly abundant organisms in the mobile scavenger stage (Goffredi et al., 2004).
Mobile scavengers assist in the redistribution of organic matter to the sediment surrounding the carcass which starts the ball rolling for the next stage of succession: the “enrichment opportunist stage”.