Once, on a youthful snorkelling holiday in Greece, I dived to snatch a small octopus from the sand below. Deposited on the hot stones of the quay, it gathered itself for a moment and then ran away, lolloping along on eight tiptoes before flinging itself back into the sea.
That was an early lesson about the personhood of the octopus. My respect deepened with learning of the animal’s remarkable brain, the largest of any invertebrate but mostly decentralised to each of its arms and legs.
Today, the cephalopods command even greater regard for their proven capacity of “sentience”, the conscious feeling of pain and emotions, good and bad. The implications have been recognised in the UK’s new animal welfare Bill. On overwhelming scientific evidence, sentience is also accepted in decapods such as crabs, lobsters and prawns.
The new recognition of intelligence and feelings in creatures of the sea has brought vigorous scientific protest against a project by a Spanish multinational to farm the common octopus, a frequent ingredient of tourist tapas and paellas.
Nueva Pascanova (NP) is siting a farm in the Canary islands to produce 3,000 tonnes of octopus per year. With new solutions to problems in incubating, hatching and raising the animals, the venture is ahead of similar ambitions by companies in Japan, Mexico and Australia.
The wild population of octopuses is declining, with some 350,000 tonnes caught each year, and prices have been rising. NP says farming will take pressure off the wild population, but critics point to the toll of ocean food that the captive creatures will need.
The octopus expert among Ireland's marine biologists is Prof Louise Allcock at NUI Galway, whose PhD study of deep-water Antarctic octopuses led to a long-term fascination with the ecology and evolution of the cephalopods (octopuses, squid and cuttlefish). She has co-authored a richly illustrated book on the animals and co-ordinates the international Red Data List for their species.
Since 2010 Prof Allcock has been leading a cruise programme, using ROVs, studying the ecosystems of the canyons of Ireland’s continental shelf and seeking new marine products in the sponges and corals of the deep sea. Her cephalopod research continues, however, and her objection to octopus farming relates to their lifestyle as largely solitary and independent animals.
Stress deaths
An influential American study in 2019, led by Prof Jennifer Jacquet of New York University, argued that octopuses were highly intelligent, curious creatures and that farming them intensively would probably cause many deaths from stress.
Last November the authoritative review of scientific evidence that has guided the UK’s new welfare Bill described octopuses as “solitary animals that are often aggressive towards each other in confined spaces. We are convinced that high-welfare octopus farming is impossible.”
Allcock cites problems already familiar from intensive Irish farming of sentient domestic animals such as pigs. Among them are tail docking and biting in sheds devoid of mental stimulation and activity.
The "sentience" now accorded to cephalopods and decapods was based on eight criteria distilled from a review of more than 500 research papers. It was initiated by the London School of Economics and led by Dr Jonathan Birch, a specialist in the philosophy of biological sciences.
The essential criteria were rooted in the networks of brain activity and physical reactions to local anaesthetics or painkillers. They went on to “motivational trade-offs that show a balancing of threat against opportunity for reward”. Then came self-protecting behaviour in response to injury and threat, and learning that goes beyond experience. Finally came behaviour “that shows the animal values local anaesthetics or analgesics when injured”.
Octopuses matched most of the criteria with the highest confidence, and even crabs did well enough to make decapods worthy of welfare laws.
Plant-based diets
Sentience, on the evidence, is not uniquely human. This, indeed had been the scientific consensus for decades, crystallised in 2012 by the Cambridge Declaration on Consciousness. This found that “non-human animals, including all mammals and birds and many other creatures, including octopuses” possess neurological networks complex enough to support conscious experiences.
Allcock adds fish to her concern, since they “are now considered to experience both pain and suffering and die slowly when harvested from the wild”. She would welcome a move to plant-based diets to help combat climate change.
The animals of the ocean are under rapid domestication and some 550 species, from shrimps to tuna, are raised in captivity in some 190 countries. Europe’s common octopus is a hefty creature found only off our south coast and Ireland’s smaller curled octopus (Eledone cirrhosa), with slender arms and only one row of suckers, seems an unlikely candidate for farming.
The accepted proofs of sentience in ocean animals, most evident in the octopus family, present new challenges to humans with any ethical conscience.