Deep-Sea Cephalopods: An Introduction and Overview

What lurks beneath...?

By Kat Bolstad

Note: Kat (Tintenfisch) welcomes discussion in the Physiology & Biology forum of the Message Board.


The deep sea is the largest, yet least-explored habitat on Earth. Its seemingly adverse conditions include crushing pressure, total darkness, and temperatures near freezing, yet a spectacular variety of delicate and primitive life forms thrive in it. Most bizarre among these are the cephalopods, found from the deepest trenches to the ocean's very surface, burrowing into or hovering just off the sea bed, on and around deep-sea reefs, hydrothermal vents and cold seeps, adrift or swimming with great speed and agility through the water column. From evolutionary accidents to the pinnacles of success, the deep-sea cephalopod fauna exhibit fascinating physiological, morphological, and behavioral modifications.


Many deep-sea squids and octopi share certain general modifications such as gelatinous tissue (containing high concentrations of ammonium ions) which approximates the density of seawater, establishing neutral buoyancy and facilitating efficient locomotion (Villanueva et al. 1997); relatively large size; well-developed eyes that can detect any motion or light within the environment; and bioluminescence, which although more frequently observed in squid also occurs in several octopods and is thought to aid in prey capture, defense and countershading (Rees et al. 1998). Modified sucker structures can be found in several species of octopus...
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About the Author
Kat joined the staff in November 2002. She completed her PhD thesis (Systematics of the Squid Family Onychoteuthidae Gray, 1847) and graduated in 2008 from the EOS Research Institute, Auckland University of Technology (New Zealand). She is now a Research Fellow in EOS, and also works at Kelly Tarlton's, the local aquarium in Auckland. Originally from Minnesota, she has spent recent years variously visiting overseas squid collections, diving, teaching ecology, biology and German. Her previous marine experience includes a semester at the National Museum of Natural History (Smithsonian) studying isopod systematics, three years at the New England Aquarium working on lobster and jellyfish husbandry, and a behavioral field study on Hector's Dolphin in Akaroa, New Zealand.


I was fascinated to read about Haliphron atlanticus in your article above. I live in the Bay of Islands and go about by kayak. I look forward to meeting Haliphron out there one day. I need a cephalopod expert to check my short story for scientific accuracy before I publish it. Would you do that kind of thing? Or do you know of some other scientist who might? The story is about an octopus. It is fiction but I want all aspects of setting and biology to be accurate.

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