Octopus etiquette

Abstract

Our views of cephalopods have evolved towards recognising them as intelligent and sentient beings, even if we’re still far from understanding their minds. On this basis, one has to ask if our treatment of these animals targeted by fisheries is adequate, and if the plans for industrial-scale farming of octopuses are ethically acceptable. Michael Gross reports. Our views of cephalopods have evolved towards recognising them as intelligent and sentient beings, even if we’re still far from understanding their minds. On this basis, one has to ask if our treatment of these animals targeted by fisheries is adequate, and if the plans for industrial-scale farming of octopuses are ethically acceptable. Michael Gross reports. We may never get the chance to communicate with intelligent extraterrestrial life forms, but as many others have pointed out cephalopods may be the closest analogy available to study. Our relation to the multi-armed molluscs has evolved from a fear of mystical sea monsters such as the kraken of Nordic legends allegedly sinking ships in the North Atlantic to the curiosity about how an invertebrate can evolve complex cognition that rivals the brains of some of our brighter mammalian friends, such as dogs. It is also worth noting that their intelligence likely evolved not only independently of but also much earlier than that of vertebrates, meaning that there may have been times when the most intelligent species on our planet was a cephalopod (Curr. Biol. (2015) 25, R775–R777). Advances in genomics and neuroscience, including those reported elsewhere in this special issue, keep revealing fresh details of the many ways in which cephalopod intelligence is different from ours. We may never fully understand what it is like to experience the world as an octopus, and this realisation should serve as a caveat for attempts to find and contact extraterrestrial intelligence too. Historically, for as long as we regarded cephalopods just as the more elaborately shaped relatives of slugs and snails there was no reason not to see them as food too. Ancient Greeks and Romans already served them as delicacies, and today coastal cultures such as Galicia in northwest Spain, as well as Greece and Mexico, take pride in their cephalopod-based culinary inventions. In recent years, demand has even increased to the extent that we should perhaps pause to reflect on the way we treat these animals. Animal welfare legislation is typically focused on vertebrates, so there is little to stop humans exploiting cephalopods in whatever way appears financially lucrative. Currently, an estimated four million tonnes of cephalopods are fished every year according to the Smithsonian Institution. Of these, around three quarters are squids. In the Gulf of Thailand, bright lights are used at night to lure plankton to the surface and the squids that follow them are caught — making the activity visible from space. Nautiluses, evolutionarily unique as the only surviving cephalopod family that retains the ancestral shell, are also hunted for their nacre, which is used in jewellery. All Nautilus species are listed in the CITES Appendix, but there is very little data on their population status. Octopuses and cuttlefish each account for around 350,000 tonnes annually. Species targeted include the Australian giant cuttlefish (Sepia apama, Near Threatened), which has seen some population declines leading to conservation concerns, as well as the common octopus (Octopus vulgaris, Least Concern) found in large parts of the Atlantic, which is also one of the most widely studied cephalopods, and one of the most intelligent species. The annual catch of O. vulgaris is on the order of 20,000 tonnes. As an adult individual weighs around nine kilograms, this amounts to more than two million animals being killed and eaten. Deeply ingrained in many coastal cultures, this mass slaughter hasn’t provoked much protest from animal rights campaigners so far. They did perk up, however, when the industrial farming of O. vulgaris became a very realistic prospect for the near future. While there have been efforts towards octopus farming in several countries, the Spanish aquaculture and fisheries company Nueva Pescanova became the leader of this field in 2019 when it succeeded in reproducing the entire life cycle of O. vulgaris in its experimental tanks. Since then, the company, based in Redondela in seafood-loving Galicia, has been continuing its research into octopus breeding with a view towards opening an industrial-scale farming site in Gran Canaria, for which planning applications were filed in 2021. Marine biologists and animal welfare organisations swiftly objected to the project on the grounds that factory farming environments are exactly the opposite of the conditions that these intelligent animals need for a happy octopus-like life. A report written by Elena Lara for Compassion in World Farming International puts it bluntly in the title ‘Octopus Factory Farming: A Recipe for Disaster’ (https://tinyurl.com/3c6y8sz4). Octopuses are solitary and playful, so the fear is that, in a tank with high population density, they would soon get bored and become destructive and possibly even cannibalistic. Scientists working with the company have claimed on the other hand that, five generations into maintaining their captive population, they aren’t observing any such behavioural problems. This might suggest that they have already succeeded in breeding a domesticated variant of the species. However, to fit their project plans, they will have to house the animals at even higher densities than they have achieved so far. Another bone of contention is the way in which the animals will be slaughtered. Given what we now know about their minds and sentience, animal rights experts insist that they would have to be slaughtered in a humane way, such that they become instantly unconscious without suffering. Fishermen have been known to club them over the head, which in view of the decentralised nature of their nervous system appears to be a somewhat dubious method. According to press reports, Nueva Pescanova now plans to kill the animals by immersing them in ice water, a method they also use in some of their aquaculture endeavours with other species. However, World Organisation for Animal Health has also objected to this practice in its Aquatic Animal Health Code. The company deflects criticism by saying that its scientists are still working on optimising a humane protocol for the slaughter.When commercial production starts in Las Palmas, the company wants to gradually ramp it up to 3,000 tonnes of meat annually, requiring the slaughter of nearly a million octopuses. Understandably, given the objections raised since 2019, the company isn’t making this very obvious on its website. Whereas there is currently no legal basis to stop the plan, the non-profit organisation Eurogroup for Animals, which is registered in Belgium, has called “for the current EU animal welfare legislative review to include a ban on production and import of farmed octopus”. The wider ecological context also needs consideration, especially if octopus farming catches on and other countries and companies join in. As the common octopus isn’t endangered, farming it will not help with any conservation issues. By making more farmed-octopus products available and marketing them accordingly, the company may just end up driving up the consumption without relieving the pressure on the populations in the wild at all. Moreover, feeding the farm population will require additional industrial-scale fishing for the octopus’s prey species, an activity that, unless handled sustainably, may cause ecological and conservation problems of its own. Most cephalopod species have a short lifespan (two to four years) and can reproduce rapidly and abundantly, and some have been observed to respond opportunistically to environmental change. Therefore, it has been widely assumed that many species will be able to adapt to and possibly even benefit from climate change, although precise data to support this idea have been sparse. Alexandre Schickele from the Université Côte d’Azur at Nice, France, and colleagues have resorted to modelling the likely effects of environmental change on three common cephalopod species found in European waters, namely O. vulgaris, the cuttlefish Sepia officinalis and the squid Loligo vulgaris (Sci. Rep. (2021) 11, 3930). The results show that, regardless of which climate trajectory is followed, conditions in the Mediterranean are likely to become less suitable for these three species, whereas the waters of the North Sea and surrounding areas are rapidly becoming more suitable. Whereas cephalopods are mobile enough to move with the climate, the authors warn that their central position in the marine food web may mean that any shift in distribution could affect the wider functioning of ecosystems. More recently, Daniel Oesterwind from the Thünen Institute of Baltic Sea Fisheries at Rostock, Germany, and colleagues have addressed the lack of long-term distribution data by combining new and historic studies across a 100-year time span (Biodivers. Conserv. (2022) 31, 1491–1518). The researchers used a historic study of North Sea cephalopods by Johann Georg Grimpe (1889–1936) in which he identified 24 species of cephalopods found in the North Sea over an 18-year period (Wiss. Meeresunters. 16, 1–124) as the baseline for the analysis of recent data. Oesterwind and colleagues found that several species identified by Grimpe have since disappeared from the North Sea, whereas seven that used to be occasional visitors or even absent have now become permanent residents. They argue that, as the North Sea’s surface temperature has warmed by one degree since then, a difference that is significantly outside the normal temperature variability, it is safe to assume that sea water warming has had some effect, even if the approach doesn’t enable precise attribution of causes. In general, the authors conclude that, while the number of species hasn’t changed dramatically, their abundance has increased and the distribution of many species has shifted northwards, as is to be expected in a warming climate. They note that fisheries are already moving along with these populations, as for instance the exploitation of the squid Loligo forbesii has now become economically viable off the coasts of Scotland. The authors also emphasise that the changes they report are bound to have significant impact on the wider food web, which warrants further investigation. Globally, cephalopods haven’t exactly been a focus of conservation research and attention. For most species, we don’t even know how they are coping with their changing environment. The IUCN Red List has 750 entries for cephalopods, and the majority (419) are currently listed as Data Deficient. Reassuringly, 324 species (43%) are Least Concern, and only seven have a status ranging from Near Threatened to Critically Endangered. In the category Near Threatened we find the Australian giant cuttlefish (S. apama) mentioned above, as well as a New Zealand octopus, Octopus kaharoa. The five species listed as Vulnerable or worse are all in the suborder Cirrina (cirrate octopuses), defined by the presence of a small internal shell and two fins. The suborder is named for the cirri, which are fibrous structures in their arms, occurring pairwise next to each sucker. The five species at risk include Cirroctopus hochbergi (Endangered) as well as four species of the genus Opisthoteuthis, also known as umbrella octopuses. Unlike most other cephalopods, the cirrates tend to have longer life spans and slower reproduction cycles, which elevates their risk of decline in response to environmental threats. The Critically Endangered roughy umbrella octopus (Opisthoteuthis chathamensis), for instance, is native to the demersal zone (i.e. habitats near the sea floor) around the Chatham Rise in New Zealand, observed at depths between 900 and 1,438 metres. It used to be a common bycatch species in the 20th century but is no longer found in fisheries. In its 2014 assessment of the cephalopod’s conservation status, the IUCN noted that “this species has suffered an 80% decline in population size over three generations as a result of increased fishing activity (which is ongoing) in deeper waters”. The species page also notes that “there are no species-specific conservation measures in place. Research is needed into the population size, and trends in both population size and harvest level.” Other umbrella octopuses share similar problems, with Opisthoteuthis mero listed as Endangered, while Opisthoteuthis calypso and Opisthoteuthis massyae are Vulnerable. The other 16 members of the genus are Data Deficient, underlining the point that more research is needed. Relations between humans and cephalopods have been shaped by the fear of kraken-like monsters, a general bias in favour of vertebrates and the culturally ingrained habit of hunting, cutting, cooking and eating these animals. With the increasing awareness that at least some of these species are highly intelligent and have some of the most interesting non-human minds to be found on our planet, it may be time to reset our standards. Animals don’t have to have vertebrae in order to merit our attention and respect. Recognising intelligent life in unexpected shapes and forms is an important skill for us to learn, especially if we are serious about the ambition to find extraterrestrials. Improving our care for and understanding of the most unusual intelligent life forms here on Earth would be a good place to start.