Seafood is widely eaten in Singapore (and universally). Often people wonder if fish and crustaceans are sentient or if they can feel pain. As they are not as expressive as other animals, this may lead some people to conclude that they are only responding to a physical reflex.

There is now, however, a growing body of evidence that fish and some crustaceans (such as crabs and lobsters) can indeed feel pain.

There are many inhumane and cruel practices which go largely unnoticed or are discounted, in terms of animal suffering. As much as it would be easy to ask consumers to refrain from eating seafood, so that fish and crustaceans are spared from pain, suffering and distress, we know it would not be a realistic expectation or solution. Seafood would still be consumed on a wide scale. But this does not mean that crustaceans and fish should be inhumanely treated whether in a commercial or home environment.

The SPCA is seeking to create awareness on this issue, and to ask the public to reflect on current practices, and to report on incidences they may witness, in relation to cruel treatment of seafood animals.

The SPCA is strongly against the infliction of pain and suffering on any animal, including those that are prepared for human consumption.

All over Singapore, it is a common sight to see tightly confined crabs in restaurants, eating establishments, markets and supermarkets, languishing with their pincers tied (as pictured here). Most people don't bat an eyelid and take this common sight for granted. Boiling of live crabs goes on as well, and this is against international guidelines.

The following are guides for anyone dealing with live seafood;

1. Most humane slaughter methods
2. Most humane transportation methods
3. Most humane housing methods
4. What else can I do?

The Agri-Food & Veterinary Authority of Singapore (AVA) is aligned with OIE (Office International des Epizooties/World Organisation for Animal Health) guidelines that the most humane manner to kill crustaceans is by first chilling them to 4 degrees Celsius.

At home, the most humane method at present of killing a crab is first to lower its body temperature, before spiking it.

The crabs should be placed in a refrigerator or freezer at below 4 degrees Celsius. Putting crabs in the freezer for two hours will generally kill most of them. It is best to lower the temperature slowly so that the shock does not cause them to suffer unnecessarily. The chill should be slow, and not inflicted on the crabs suddenly.

Crabs will generally be insensible by this time, and this can be ascertained by
- tapping their shells to see if there are any eye reactions;
- whether there is control over limb movements;
- whether there is resistance to handling, especially in the tail or abdomen;
- whether there is reaction around the mouth when it is touched.

At this point, the crab should be spiked through the brain with a sharp pointed tip. The insertion of a knife into the head of the animal will generally kill it, if it is not already dead.

Restaurants may consider machines like the Crustastun (http://crustastun.com/) which stun the animals with an electric shock which then kills them. The crab will be rendered insensible by an electric shock and then killed in less than 10 seconds.

Killing crabs humanely also increases the quality of the meat as killing by other methods increases the amount of adrenaline in the crabs. This causes the meat to be less tasty.

- For Lobsters/Crayfish

Similarly, the best way of killing a lobster is to first render it insensible, using the refrigerator/freezer method described above.

The lobster can then be further prepared. Spiking lobsters through the head may not be the most humane method to kill them. Rocklobsters, for example, have several nerve endings.

The lobster should be put on its back, with its claws tied. Lobsters have a chain of nerves running down the middle of their bodies. Determine where the midline (the middle point) is on the bottom of the lobster is. Using the midline as a starting point, trace the path to the head of the lobster, beneath the mouth parts. Cut through the head to destroy the brain, but do not sever the head.

Put your knife back on the midline, and draw it sharply towards the head. When you are done, then do the same towards the tail. You should not take more than 10 seconds to finish this entire procedure.

Restaurants and larger enterprises should consider machines that administer electric shocks, like the Crustastun. Lobsters are said to die within 5 seconds using this method. The lobster is placed in a saltwater tank and a stun button is pressed, which renders the lobster insensible, before killing it.

- For Prawns

Put the prawn into a refrigerator or freezer at below 4 degrees Celsius. This should be done until the prawn is insensible. The prawn is insensible when the tail can be extended without resistance and can be easily moved about. Its outer mouthparts will by this time, also be easily moved. Death will usually occur at -15 degrees Celsius. However it is best to reduce the temperature slowly, so that the prawn does not go into shock.

The prawn should then be humanely killed by rapidly cutting through the centerline of the head and tail.

Restaurants should consider designating people who are experienced to humanely kill the prawns. This will not only allow for it to be done more humanely, but more efficiently as well.

- For Fish

Fish should be kept in water until just before they are to be killed. To humanely kill a fish, they should be stunned or spiked. (http://kb.rspca.org.au/What-is-the-most-humane-way-to-kill-a-fish-intended-for-eating_451.html)

Stunning is the killing of the fish by an accurate and strong blow to the head. The blow should be aimed just above the eyes so that the brain is targeted. If the fish does not look dead, then another blow should be attempted.

Spiking involves using a sharp spike through the brain of the fish. The spike should again be placed in a position to penetrate the brain of the fish. It should then be driven sharply into the brain. The blow should produce immediate unconsciousness and the spike should then be moved around from side to side to destroy the brain.

It is also possible to chill the fish slowly in a refrigerator or freezer (as stated above) and then to decapitate the fish.

Restaurants should consider designating people who are experienced to humanely kill fish. This will not only allow for it to be done more humanely, but more efficiently as well.

What Not to Do

The following methods are not advised because they are not humane methods.

- For Crabs

Avoid the following methods of killing crabs as they cause unnecessary suffering:
- Throwing the crabs in boiling water;
- Removing the shell of the crabs while it are still alive;
- Pulling the pinchers off crabs while they are still alive;
- Introducing Carbon Dioxide into the water;
- Leaving crabs to drown in freshwater;
- Steaming crabs while they are alive;
- Microwaving crabs alive.

Boiling or steaming crabs while they are alive causes the crabs to produce more adrenaline which causes the meat to be less tasty.

- For Lobsters/Crayfish

Avoid the following methods of killing lobsters/crayfish:
- Throwing lobsters/crayfish into boiling water;
- Removing parts of the lobsters/crayfish while still alive;
- Leaving them to drown in freshwater;
- Introducing carbon dioxide into the water;
- Microwaving lobsters/crayfish alive.

- For Prawns

Avoid the following:
- Throwing prawns in boiling water;
- Cooking/soaking them alive in wine;
- Eating prawns alive;
- Microwaving prawns while they are alive.

- For Fish

These methods do not result in a quick and humane death for the fish and should be avoided:
- Chilling the fish with ice in the water used to hold the fish;
- Carbon dioxide added into the water used to hold the fish;
- Chilling with ice and carbon dioxide in the water used to hold the fish;
- Salt or ammonia baths;
- Asphyxiation of the fish by removing them from water;
- Bleeding the fish without first stunning them.

Cutting up a live fish without first stunning or spiking it also releases adrenaline which will compromise the quality of the meat.

It is not just the process of killing crustaceans and other marine animals that causes them stress. Often, transporting and housing these creatures can cause much suffering and discomfort to them too.

Here are some tips in respect to humane transportation.

- For Crabs

If the journey is a long one, then the crabs should be placed in a cooler box that is covered with ice or cold gel packs at the bottom. The crabs should not be allowed to come into contact with the melted ice.

- For Lobsters/Crayfish

Live Lobsters and crayfish can be brought home in seawater/freshwater, depending on what type of lobster or crayfish they are. Do not store seawater lobsters in freshwater.

- For Prawns

Prawns should be placed in thick plastic bags partly filled with water and containing air, or preferably oxygen.

Do not place too many prawns in a bag.

- For Fish

Fish should also be transported in thick plastic bags filled partly with water, and containing air, or preferably oxygen.

As there are numerous welfare problems associated with housing live seafood at restaurants or supermarkets, it is best if the more humane option of pre killed frozen seafood is chosen.

It is best not to house any of these animals for too long either at home or at a restaurant. Particularly with home cooks, it is best to purchase live seafood just prior to preparing them for consumption.

The animals should be handled as gently as possible so as not to cause too much stress. Different species should also not be stocked together, nor should too many animals be stored in one tank as this will cause overcrowding. Waste products should also be removed promptly. All animals should be fed if they are kept in the tanks beyond a day or two.

- For Crabs

You can leave the crabs in a container and drape the crabs with wet towels. Ensure that the crabs have enough air or they will suffocate. Ensure that they are kept in a cool and airy area. You may also place them in a refrigerator, however they will not last for very long out of their environment.

Restaurants should ensure that the crabs are not kept in overcrowded conditions. If the crabs are kept for a while, they should not be starved and must be fed.

- For Lobsters/Crayfish

Lobsters need cool temperatures and hence they should be placed (along with their carton) into the refrigerator with a piece of wet newspaper placed over them immediately upon returning home. Lobsters do not do well in warm weather so do not leave them exposed to warm temperatures.

Do not pick a lobster up by the claws. Always handle it gently. You should also not stress the lobsters by putting too many in a carton.

Restaurants should also ensure that lobsters are kept in a stress free environment prior to cooking. They should not be removed from tanks or the refrigeration until just before preparing them to be killed.

If they are kept in tanks, the water should be clean and the lobsters should not be overcrowded. Water quality should be monitored. The tanks should not have cloudy or dirty looking water.

The levels of ammonia should also be monitored to ensure that the lobsters are not stressed. Do not allow customers to tap on the tanks as this stressed the lobsters out.

- For Prawns

Do not put the prawns in tap water as they are likely to react badly to the chlorine. Ensure that they have enough oxygen.

Restaurants should be careful not to overstock their tanks and to monitor their water quality. If these are saltwater prawns, then they should be placed in saltwater. An oxygen stone to provide oxygen should be added, and the prawns should be fed daily.

- For Fish

Home cooks should ensure that the fish have enough water and are not gasping for air. There should be sufficient oxygen so that they are not suffering. If for some reason the fish is not cooked immediately, it is best to transfer it to a basin or large container with enough water.

Restaurant tanks should be monitored to ensure that the fish are kept in conditions that are as stress-free as possible.

- Ask your seafood supplier, supermarket or restaurant how the seafood is killed. Do they have designated, experienced people who are in charge of killing the seafood humanely? What methods do they use? If they use methods that are inhumane, please let them know there is a better alternative or consider changing to another supplier or taking your business to another supermarket or restaurant.