Details of plans to create the world’s first octopus farm in Spain have been leaked to the BBC.

The mollusks have never been intensively farmed and some scientists call the proposed method of killing them in ice water “horrific”.

The Spanish multinational behind the project denies harming the octopuses.

The confidential documents on the Nueva Pescanova proposal were sent to the BBC by the “Eurogroup for Animals”, an organization that seeks to improve the treatment of animals in the EU.

Nueva Pescanova referred the proposal to the Canary Islands’ General Directorate for Fisheries, which did not respond to a BBC request for comment.

Octopus caught in the wild using pots, lines and traps is eaten around the world, especially in the Mediterranean, Asia and Latin America.

The race to discover the secret of their captive breeding has been going on for decades. The task is difficult, as the larvae eat only live food and require a carefully controlled environment, but Nueva Pescanova announced in 2019 that it had made a scientific breakthrough.

The prospect of intensive octopus farming has already sparked protests: lawmakers in the US state of Washington have proposed banning the practice before it even begins.

Pescanova’s new plans involve keeping octopuses, dark-acclimated solitary animals, in tanks with other octopuses, sometimes under constant light. The creatures – of the Octopus vulgaris species – are said to be housed in around 1,000 communal pools in a two-storey building in the port of Las Palmas de Gran Canaria.

To kill them, they are kept in containers with water at a temperature of -3°C, according to the documents.

Because octopuses have never been raised commercially, there are currently no animal welfare laws to protect them.

However, studies show that this method of killing using “ice sludge” leads to a slow and stressful death for the fish.

The World Organization for Animal Welfare says it harms fish welfare and the Aquaculture Stewardship Council (ASC), the main certification program for aquacultured seafood, has proposed banning it unless the fish are first stunned.

This is why some European supermarkets have stopped selling frozen fish.

Professor Peter Tse, a neurologist at the University of Dartmouth in the US, told the BBC: ‘Icing them to death is a slow death…it’s very cruel and should not be allowed.’

He added that they were “as smart as cats” and suggested that the most humane way to kill them, as many fishermen do: is by hitting them on the head.

Nueva Pescanova aims to produce 3,000 tons of octopus a year to supply “high-end international markets” including the United States, South Korea and Japan.

That equates to one million animals, with 10 to 15 octopuses living in each cubic meter of pond, according to the environmental group Compassion in World Farming (CiWF), which studied the projects.

In its document, Nueva Pescanova estimates that there will be a “mortality rate of 10 to 15%.”

Jonathan Birch, associate professor at the London School of Economics, led the review of more than 300 scientific studies.

Mr Birch’s analysis led to the recognition of octopuses as “sentient species” in the UK Animal Welfare Act 2022.

Mr Birch and the study’s co-authors believe it is “impossible” to raise octopuses to high welfare standards and that killing them in ice slush “may not be an acceptable method in the laboratory”.

“A large number of octopuses should not be close to each other, which creates stress, conflict and a high mortality rate (…). This creates stress, conflict and a high mortality rate (…) The mortality rate is 10 to 15%, regardless of the breeding type. should not be accepted.”

Speaking to the BBC, Nueva Pescanova said: “The welfare standards required for the production of octopus or other animals in our breeding farms ensure that the animals are handled appropriately. This includes handling that avoids pain or suffering to the animals (…)”.

In the wild, octopuses are active and fiercely territorial hunters. Nuova Pescanova proposes that farm animals be fed dry food produced industrially from the “removal and by-products” of fish.

The tanks are filled with seawater from a nearby bay. They vary in size depending on the different life stages of the octopus, and the salinity and temperature are tightly controlled.

The first litter of 100 octopuses, 70 males and 30 females, came from the research center Centro Biomarino Pescanova in Galicia.

The plans state that the company has reached the “domestication” stage of the species and “shows no significant signs of cannibalism or competition for food”.

CiWF’s Elena Lara called on authorities in the Canary Islands to block the construction of the farm, which would “cause unnecessary suffering to these intelligent, sensitive and fascinating creatures”.

Reineke Hameleers, Eurogroup’s executive director for animals, said the European Commission was reviewing its animal welfare legislation and there was a “real opportunity” to “prevent terrible suffering”.

In addition to the well-being of the octopuses, the wastewater produced by CiWF farming is discharged into the ocean.

Octopuses produce nitrogen and phosphate waste. “The water entering and leaving the plant will be filtered in such a way that there is no harm to the environment,” Nueva Pescanova told the BBC.

About 350,000 tonnes of octopus are caught each year, 10 times the number caught in 1950, putting pressure on these stocks.

Nueva Pescanova affirmed that “fish farming is the solution to ensure a sustainable yield” and that it will allow the “octopus species to repopulate in the future”.

However, conservationists believe that agriculture can create new markets to lower prices.

Nueva Peskanova stressed to the BBC that “it has put a lot of effort into promoting responsible and sustainable performance throughout the value chain to ensure best practice is followed”.

The Gran Canaria government did not respond to a request for information.