Ever wondered what happens when a whale dies in the ocean? Joanna Bagniewska explains
Dead whales sink to the ocean floor, reaching depths of several thousand metres relatively intact. Their lipid- and protein-laden bodies create unique, nutrient-rich ecosystems that may sustain creatures of the abyss for decades.
The whales’ flesh is picked away by sharks, crabs and hagfish – the latter can absorb nutrients directly through their skin while they forage inside carcasses.
Whale skeletons are then covered with colourful, delicate, flower-like creatures – zombie worms. These underwater relatives of the earthworm don’t have a mouth and guts, but instead secrete acid and enzymes to drill into bones, and feed with the help of symbiotic bacteria.
The acid borings also double up as shelter holes, and a single whale skeleton can house between half a million and a million adult zombie worms.
Unfortunately, commercial whaling reduces the number of sunken carcasses, and thus removes valuable sources of nutrients, potentially leading to a lower species richness in the depths.
Main image: humpback whale © Getty Images