Campaigners in Taiwan are calling for an end to the centuries-old practice of fish tethering – which sees live fish tied into a crescent shape to entice buyers – claiming the custom “is a form of torture” and contravenes animal welfare standards.

Fish tethering is popular in Taiwan, where it is believed that “bow fish” stay fresher for longer if they are bent into a curve and sprinkled with water to keep them alive. They remain this way until they are purchased, which can be up to 10 hours after they were caught, say activists.

“In Chinese communities, fish are typically not considered to be fresh if they have been dead for a long period of time,” said Wu Hung of the Environment and Animal Society of Taiwan (East).

“This explains vendors’ motivation to keep the fish alive until the time of sale. But it is well established that fish are vertebrate sentient beings, and given that they are reared and managed in aquaculture systems, they are subject to regulation under the Animal Protection Act and should not be treated cruelly.”

Fish tethering is believed to be practised on around 3m giant sea perch in Taiwan every year. The fish, which are also known as barramundi or Asian sea bass, are caught from one of the many sea perch aquaculture farms that dot the south-western coast, according to Wu.

Sea perch farms comprise one of Taiwan’s major fishing industries, with total production in 2017 – the latest figures available – amounting to some 20,160 tonnes, according to East. While two main species of sea perch are farmed in Taiwan, including both the Japanese sea perch (Lateolabrax japonicas) and the giant sea perch (Lates calcarifer), it is only the latter that is tethered, said Wu.

Canadian photojournalist Jo-Anne McArthur recently travelled to Taipei’s central fish market, where she documented the fish tethering process.

Workers forcefully prise open the gills to increase airflow, then puncture a hole in the fish’s mouth with a sharp bamboo stick or similar implement. The worker then feeds a thread through the hole in the mouth to secure a knot, bends the fish into a crescent shape, ties another knot around the tail, and tightens the thread so that the fish is unable to move.

Fish tethering is believed to have originated during the Ming dynasty more than 200 years ago in China, said Wu, where the custom is still practised on certain species of farmed fish.

Tethering sea bass at Taipei fish market

“The practice is purported to have stemmed from the lack of oxygenating equipment at the time, as binding forcefully opens the fishes’ mouths and gills, and is said to increase oxygen absorption and prolong their death,” said Wu.

“Vendors will also splash water on the fish to keep their skin and gills moist, to further this effect.”

The practice is not endemic to Asia alone, however. Undercover footage taken last year by campaign group Essere Animali of intensive fish farming in Italy shows what appear to be sea bass being tied with string into a crescent shape with the caption: “Fish are tied with a string that runs through their gills. This painful practice is required by some companies to guarantee their freshness.”

Under normal circumstances, fish removed from water suffer hypoxia and suffocate – but how long that takes depends on the size and species of fish, as some can live for months out of water. Tethering prolongs a fish’s suffocation, says Wu, but only works on certain species and is really only effective in humid environments.

Fish vendor Lin, at Nanya fish market in New Taipei City, said tethering allowed for sea perch sales to continue throughout the day: “The purpose of tethering is to keep them alive longer.”

Krzysztof Wojtas, head of fish policy at the lobbying group Compassion in World Farming (CIWF), described “traditional” methods such as fish tethering as a “a form of torture” and serve to underline how few welfare standards pertain to fish around the world.

“Fish are really neglected when it comes to animal welfare standards,” said Wojtas.

“All the scientific evidence now points to fish not just feeling pain, but distress as well. We know that they are extremely intelligent, have complex social behaviours and that some can even use tools. Recently, one species even passed the mirror test, which demonstrates self-awareness.

“But when you look at other animals that humans eat, say cows and pigs, there is so much debate here in the EU about how they are reared and the number of seconds it can take for a pig to lose consciousness before slaughter. With fish we’re talking about hours, just to put things in perspective.”

Humane slaughter for fish is still in its infancy worldwide. While some nations – among them the UK and Norway – require humane killing practices for farmed fish, the vast majority of fish caught from both farms and in the wild are simply left to suffocate.

In Taiwan, vendors beat the head of bow fish in order to induce unconsciousness, but it is common for the fish to continue to flap or struggle while being killed or having their scales scraped off, said Wu.

If a fish is conscious during slaughter and struggles, lactic acid and hormones such as adrenaline and cortisol are likely to flood into the fish’s bloodstream, potentially tainting the meat itself, said Wojtas.

“This is well established in land animals, where if an animal hasn’t been slaughtered humanely and has suffered as a result, the meat is not suitable for consumption. If a fish also struggles during slaughter, it will have more bruises in its flesh and the meat itself will be of lower quality.”

Under Taiwan’s Animal Protection Act, animals prepared for slaughter cannot be tied up “without being humanely rendered unconscious first”, says Wu. But fish markets do not fall under the definition of an abattoir, exempting them from the law.

Intensive lobbying by East saw Taiwan’s law-making body, the Legislative Yuan, demand in 2016 that the fisheries agency produce a report on aquatic animal welfare initiatives. Yet the report has still not been published, said Wu.

“Taiwan’s laws are yet to require that fish slaughter adhere to humane slaughter methods, and a humane slaughter code of practice for fish has not been published.”

Chih-Yang Huang, an associate professor in aquaculture at National Taiwan Ocean University who has worked on the government’s aquatic animal welfare initiatives, said the focus so far has been on training, inspections and the issuing of permits for safe and healthy fish farms.

Whether any of that training would affect workers in wet markets or buyers of bow fish is yet to be seen, he said.

“The concept of animal welfare started very late in Asia,” said Chih-Yang.

“We need more information, knowledge, technology and training so that animal welfare can be gradually implemented into industry and consumer markets.”