Support us | Visit us | Contact us
26 September 2012Title:Vampire Squid: Detritivores In The Oxygen Minimum Zone Authors:Hendrik J. T. Hoving and Bruce H. RobisonJournal:Proceedings of the Royal Society B
Since marine biologists first examined vampire squid about 100 years ago, it has been a mystery how and what they eat. A new paper published in Proceedings of the Royal Society B today, shows for the first time that, unlike its relatives, the octopuses and squids, which hunt live prey, the vampire squid uses two thread-like filaments to capture bits of organic debris that sink down from the ocean surface into the deep sea.
A vampire squid in a typical feeding position, drifting horizontally in the deep sea with one of its filaments extended. (c) 2011 MBARI
Previous researchers have examined the contents of vampire squids’ stomachs with inconclusive results. Postdoctoral fellow Henk-Jan Hoving and senior scientist Bruce Robison, from The Monterey Bay Aquarium Research Institute, have discovered that vampire squids eat mostly "marine snow"—a mixture of dead bodies, faeces, and mucus which they collect with long filaments which extend up to 8 times as long as their bodies.
Hoving and Robison collected living vampire squids and were able to keep them alive in the laboratory for months at a time. Hoving found that when pieces of microscopic animals were placed into a tank with a vampire squid, they would stick to one of the string-like filaments that the animal extends outward from its body. The vampire squid would then draw the filament through its arms, removing the particles from the filament and enveloping them in mucus. Finally, the squid would transfer the glob of mucus and particles to its mouth and consume it.
The organic detritus that forms the bulk of the vampire squid's diet are not particularly nutritious. However vampire squids complement their frugal diet with an extremely energy-efficient lifestyle and unique adaptations. Their bodies are neutrally buoyant, so they don't have to expend energy to stay at a particular depth, and they don't have to swim to find food, but simply extend their filaments to collect food that drifts past them.
Vampire squids don't have to expend much energy avoiding predators either, as they live at depths where there is so little oxygen that few other animals can survive. Conveniently, these deep, low-oxygen zones are often found below where there is an abundance of life near the sea surface, which creates lots of marine snow for vampire squids to eat. Hoving explains, "Because of its unique adaptations, the vampire squid is able to permanently and successfully inhabit the center of the oxygen minimum zone, an otherwise hostile environment where the vampire squid's predators are few, and its food is abundant."
Even though Hoving and Robison's research shows that the vampire squid is a "detritivore" rather than an active predator, its sinister appearance and stealthy habits will no doubt continue to fascinate both researchers and the general public.
Learn about our mission to expand the frontiers of knowledge.
Explore our annual science exhibition
A paper published in Biology Letters today reveals a new species of ichthyosaur (a dolphin-like marine reptile from the age of dinosaurs) which revolutionises our understanding of their evolution and extinction.
Pioneers of the Internet, computing, climate modelling and virtual surgery are just some of the experts who have been announced as new Fellows of the Royal Society today (3 May 2013).
The Royal Society, the UK’s national academy of science, has announced the appointment of 27 new Royal Society Wolfson Research Merit Award holders.
For a full archive please see the news pages.
Latest press releases about our activities.
Announcements about articles in our journals.
There are about 1,450 Fellows and Foreign Members.
We have had 350 years at the heart of scientific progress.
Contact the Society's press team.