When a large marine mammal like a whale dies, its carcass drifts to the ocean floor in an event known as a whale fall. Over the course of a decade, successive marine creatures strip the whale’s body and burrow into the bones to find nutrients, feeding on the whale’s carcass. In a new video from the Ocean Exploration Trust, scientists return to Whale Fall off the coast of British Columbia for the third time in a decade to catch a glimpse of life still clinging to the whale’s decaying skeleton.
We all know about the cycle of life (play the Lion King music), but it’s one thing to understand the engine of life and death that drives the Earth; it’s quite another to see it in action.
In 2009, researchers from the Monterey Bay Aquarium Research Institute discovered the carcass of a possibly 16-foot gray whale (Eschrichtius robustus) decomposing at the bottom of Clayoquot Slope, off the coast of British Columbia. The biological migration of a dead whale’s carcass to deep-sea resting places is called “whale fall” and is critical to the survival of organisms living in food-poor areas of the ocean.
Related
The whale’s decaying carcass was discovered at a site called the Clayoquot Slope Bullseye, where scientists from Ocean Network Canada (ONC) monitor methane gas leaking from the ocean floor. In 2012 and again in 2020, ONC scientists made a brief detour to revisit the site, about 4,100 feet below the ocean’s surface, to document the growth of marine life living among the whale’s skeleton.
ONC, along with the Ocean Exploration Trust’s (OET) EV Nautilus, will return to the site in 2023 and find the skeleton still teeming with life, almost 15 years after the remains were discovered on the ocean floor. Thankfully, they’ve uploaded footage of this incredible discovery to YouTube.
“The skeleton supports a rich benthic fauna (organisms that live near the ocean floor) including many invertebrates and several fish species, such as Cocculina craigsmithi (gastropod), Mitrella (Astyris) permodesta (butynoid gastropod), Ilyarachna profunda (isopod), Paralomis multispina (crab), Coryphaenoides acrolepis (rattail fish) and Lamellibrachia cf. barhami (tube worms),” OET wrote in a blog post about the recent survey. “These tube worms, likely the same individual seen in 2009, are still resident in the whale’s left jawbone, which is remarkable.”
Whales’ bodies break down in three stages – by mobile scavengers, nutrient-rich opportunists and sulphur-loving animals – and each stage provides unique benefits to a range of deep-sea creatures.
For example, in 2019, scientists at the Monterey Bay National Marine Sanctuary discovered a fresh whale carcass containing eels stripping fat from the skeleton while feeding a deep-sea octopus in the migratory scavenger stage. Eventually, burrowing organisms in the enrichment opportunist stage move in, and finally, in the final sulfurophile stage, bacteria break down the bones and convert embedded lipids into sulfur.
This year’s expedition will also include a photogrammetric survey, adding to existing data from previous voyages to the site and providing marine biologists with an incredible dataset detailing the entire life cycle of the whale’s fall.
In the depths of the ocean and in other ecosystems around the world, death is the beginning: after all, the cycle never ends.
Darren lives in Portland, owns cats, and writes/edits about science fiction and how our world works. If you look hard enough, you can find his previous writing on Gizmodo and Paste.