Life After Whale (On Whale Falls)

Sharon Shattuck and Flora Lichtman for Sweet Fern Productions

When a whale dies, the story has just begun. The massive carcass sinks to the seafloor, where it provides food for a deep sea ecosystem on the otherwise mostly barren seafloor. There are several stages to the whale fall ecosystem as different parts of the whale are used up. In the first phase, mobile scavengers such as ratfish, hagfish and sharks smell whale on the water and swim from afar, feeding for up to two years on the dead whale's soft flesh. In the second phase (the enrichment opportunist phase), worms, crustaceans and mollusks feed on leftover blubber, often burrowing into the nutrient-enriched sediment beneath the whale for around two years. The final stage, called the sulfophilic stage, can last decades. With only the skeleton remaining, bacteria begin breaking down lipids trapped inside the bones, generating sulfur, which attracts more bacteria and a larger community of diverse and rare species including mussels, worms, snails, and others. This diversity of species found in this last stage is larger than any known community on the deep seafloor.