Fishes and other Sea Animals Articles from All-Creatures.org

The Eye Mutilations of Factory-Farmed Crustaceans

From VeganFTA
August 2024

Eyestalk ablation is the process of removing or constricting the eyestalks of female shrimps or prawns in factory farms to induce maturation and spawning. It often involves pinching the eyestalk off, slitting with a razor blade and then squeezing out the contents, cauterising it or ligating it... a crude method of hormonal manipulation.

The most common factory-farmed animals in the world are crustaceans. About 100 species of crustaceans are farmed in the horrible conditions of aquaculture factory farms. Shrimps and prawns are the most often farmed, with species of the genera Litopenaeus, Penaeus, Fenneropenaeus, Farfantepenaeus, Macrobrachium, and Pandalus being the most common.

Virtually all farmed shrimp are of the family Penaeidae, and just two species, Whiteleg shrimp (Penaeus vannamei) and Giant tiger prawn (Penaeus monodon) account for roughly 80% of all farmed shrimps. These shrimps spend their lives in captivity in cramped conditions (which is what factory farming of any species is based on), which can lead to increased aggression, competition, cannibalism, and stress. However, in addition to this suffering common to all factory-farmed animals, many captive shrimps and prawns also experience a cruel type of mutilation that many people are likely not aware of.

The cramped captive conditions in which these crustaceans are kept in aquaculture have generated fertility problems, and the farmers have devised a gruesome and cruel method to attempt to solve them: Eyestalk ablation.

Eye Mutilations

The eyes of crustaceans are not small or simple. On the contrary, they are very sophisticated organs. Crabs’ and lobsters’ eyes are set on stalks which enables them to see all around and in different directions at once. Peacock mantis shrimps (Odontodactylus scyllarus) have the most complex set of eyes in the Animal Kingdom. Each eye contains 12 photoreceptors that allow them to sense different types of colours (human eyes only have three types of light-sensitive cells for seeing red, blue, and green), and they can see polarised light. Scientists believe that mantis shrimp take all the visual information they see into their brains at once without processing it, allowing them to react to their surroundings as quickly as possible. Their independently roaming eyes and trinocular vision explain why they are such efficient predators.

Eyestalk ablation is the process of removing or constricting the eyestalks of female shrimps or prawns in factory farms to induce maturation and spawning. It often involves pinching the eyestalk off, slitting with a razor blade and then squeezing out the contents, cauterising it or ligating it.

Ablation of eyestalks is a crude method of hormonal manipulation. By cutting, cauterising, or tying (“ligation”) of one (unilateral) or two (bilateral) eyestalks, the farmers aim to reduce the level of gonad inhibiting hormone (GIH/MO-IH) which is produced by the X-organ and sinus gland complex situated in the optic ganglia of the eyestalk.

The Cruelty of Eyestalk Ablation

This cruel practice will not only be painful but also it will cause other negative effects on the physiological, metabolic, hormonal and immune systems of these animals. It will also cause problems in sensory perception and the ability to swim, and can even affect survival rates.

Numerous scientists have found that the procedure appears to cause stress, trauma, and pain, with Australian vet Anthony Rowe describing it as, a “practice that would defy the most fundamental animal welfare standards in vertebrates, yet is routinely practised on invertebrates.”

Crustaceans are sentient beings with the capacity to suffer pain, and although this applies to all arthropods, decapod crustaceans, the group these shrimp belong to, have been officially recognised as sentient beings in several jurisdictions. For instance, a 2005 report by the European Food Safety Authority (EFSA) for the European Commission concluded that the largest of the decapods have a pain system and complex cognitive capacity and therefore were assigned Category 1 status (animals who can experience pain and distress). Additionally, New Zealand, Norway, Switzerland, and Canada, also consider decapod crustaceans as sentient beings, and recently this legal recognition also took place in the UK since the Animal Welfare (Sentience) Act 2022 was passed.

There has been lots of research showing how decapods can feel pain. For instance, research from Barr et al. (2008) found the presence of opioids and opioid receptors in crabs, leading them to postulate that some crustaceans may possess an analgesic system like that found in vertebrates. Crabs have shown memory of aversive stimuli and learnt to avoid electric shocks by refraining from entering the environment associated with the painful stimulus, rather than simply escaping from it. Research from 2015 found that a painful situation triggers a stress response in crabs. Other studies have shown that crustaceans rub and hold an injured area, as well as limp and reduce the use of injured body parts, also suggesting that they feel pain.

Therefore, eyestalk ablation will undoubtedly cause pain to the shrimps and prawns who experience it. This has already been proven. Studies have shown that shrimp and prawns display behaviours associated with pain during and after eyestalk ablation, which include tail flicking, rubbing the affected area and flinching. For instance, a 2012 study by Diarte-Plata et al. titled “Eyestalk ablation procedures to minimize pain in the freshwater prawn Macrobrachium americanum,” studied three groups and two controls of shrimps to determine the amount of stress caused by unilateral eyestalk ablation, unilateral eyestalk ablation and covering to allow coagulation, and ligation at the base of the eyestalk (the control groups were only manipulated but not ablated).

These scientists concluded that:

the trauma caused by the treatments in M. americanum was reflected by behaviours related to pain, including tail flicking as a reflex response to allow escape and rubbing the affected area. In addition, we also observed alterations in five behaviours. Four behaviours were directly related to pain and discomfort – non-sheltering, disorientation, recoil and stooping – and the fifth, feeding behaviour, was related to the hormonal disorder caused by the extirpation of the X organ sinus gland. The variables that were directly affected by the treatments were bleeding, ligating and hormonal state. The treatment that caused the most significant negative stimulus was ligation. The animals in the ligation group exhibited up to 50% more flicking, 90% more rubbing, 50% more disorientation, and 80% more recoil than the animals in the other subgroups.

Due to the cruelty of this practice, there are now some crustacean factory farms in Brazil, Colombia, Ecuador, México, and Thailand that are no longer using eyestalk ablation, but it is still used around the world. The UK supermarket Marks and Spencer has claimed that their supply chain of warm-water prawns is 100% eyestalk ablation free, and its competitor Waitrose claims to have a strict policy “prohibiting eyestalk ablation in shrimp (prawn) broodstock reproduction.” Nevertheless, the breeding of crustaceans in factory farms continues to be a cruel practice, and as killing them by fishing them directly from the sea is also cruel, the only meaningful ethical stand is to stop the consumption of crustaceans altogether — which, together with stopping the rest of animal exploitation, is what the vegan world paradigm is all about.

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Posted on All-Creatures.org: August 19, 2024
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