Frequent Question #1: “Why don’t you just cut its head off?”
Frequent Question #2: “Just smack its head with a fish bat.”
Usually, personal agendas lurk behind such statements. The tendency to defend existing habits and practices is common (and normal) and staking out positions on mortality is not our role. But it may be fair and helpful to explicate some of these different approaches when it comes to the manner of death, and the consequences of timing.
Decapitating a live fish does sever the brain’s functionality from the central nervous system. There is some debate as to how long the fish (or any other animal, for that matter) will remain “conscious” following decapitation—that debate goes to subjective questions of cruelty, which we do not address. But severing the brain’s ability to control its muscles does confer great benefit, which is exactly what decapitation achieves. Stopping the brain’s ability to send electrochemical signals to the fish’s muscles means the muscles cannot react to the stress caused by suffocation or harm. Moreover, decapitating a fish will also sever the dorsal artery, which will allow the fish to passively bleed — a second plus. So, if the handler has no use for the fish’s head, and she might otherwise allow the fish suffocate to death in a relatively hot container, decapitation is the better option. Indeed, the benefits outweigh the risks of the alternative in this instance. And, there may be applications for which this may be a good approach to ensuring the best results. (For instance, limited space in a cooler.)
However, decapitating a fish in order to kill the fish may introduce problems, depending on context. First, decapitation requires some skill and a serious knife to get through the spine in a minimally destructive way. Most will simply utilize an undersized or even a serrated blade in order to saw and cut through a live fish, which is a surefire way to increase the surface area of muscle tissue exposed to the elements (i.e., blood, other bacterial contamination in the air/water). This is not unlike the approach taken towards cutting bait, and cut bait is not the desired result. Second, decapitation can also introduce micro-tearing in the muscle tissue due to the force required to restrain a live fish’s body. That’s a bad thing if the same cut will sever the dorsal artery — the immediate flow of blood will coat these exposed tissue surfaces to bacteria-laden blood. Third, a fish’s head presents clear indications of the fish’s suitability for consumption. Because chefs and others frequently rely on certain parts of the fish’s head to evaluate quality and freshness (e.g., eye clarity/gill color), removing a critical evaluation point is frustrating for that level of selectivity. It goes without saying that removing a fish’s head may also obscure the exact type and species of a fish.
Finally, a great number of cuisines value the opportunity to either present a fish whole (i.e., in the round) or to section a fish into its constituent parts (nose-to-tail). Separating the fish’s head from its body as a method of slaughter may therefore limit the market opportunities available for the commercial producer, and that is especially true where market opportunities exist for whole fish in their most pure and unadulterated form.
Fish bats (a.k.a. priests, bonkers) are useful tool when used properly to “stun” the fish. “Stunning” is merely a euphemism for killing fish with a percussive blow to the head, and there are a number of tools available. A well-placed blow using a standard wooden or aluminum fish bat helps deliver a level of brain trauma that causes immediate brain death. For this reason, fish bats and priests are common on offshore boats. You may also see chefs or other processors using the back of a large knife or cleaver. In some aquaculture contexts, fish slide head-first down a tapered chute, and once squeezed at the bottom, a pneumatic, mechanical hammer slams into the top of the fish’s head. We only perceive three downsides to percussive stunning options: 1) the risk of user error that may prolong/exacerbate the fish’s stress level; 2) the risk of injury to the handler or others; and 3) limited angles. Each of these risks are somewhat related. A forceful swing at a fish’s head risks damaging expensive capital equipment, fragile fiberglass, or passenger safety, and doubly so on crowded or tight boat decks. Moreover, the fish’s head may be a relatively small target. Even a large tuna’s head presents a small margin for error. Missing the target can make matters worse. For one, the handler may prolong or even exacerbate the stress that a fish is experiencing out of water, and second, the handler may enrage a large fish with a non-lethal blow to the head; offshore anglers know that the errant tail kick of a large pelagic fish or a shark can cause serious bodily injury or even death to an angler. Large game hunters know too, that a targeted animal must present the right angle to the hunter — shooting in the animal’s general direction does not guarantee a safe and immediate death. The same is true for bats and priests that require a windup and a good angle from which to strike. To use a bat/priest effectively then, the top of the fish’s head must be positioned almost perfectly to the person taking the swing. If the handler misses the top of the head and strikes the body inadvertently, a contusion will result, which is effectively a bruise. Bruises and other forms of internal bleeding do not “heal” in dead animals because the animal no longer has a functioning immune system. Bruises are effectively broken blood vessels that allow blood to seep into the muscle tissue, and blood in the muscle tissue means bacteria in the muscle tissue. Bacteria in the muscle tissue go on to become the first sites of premature spoilage and decomposition.
A brain spike presents a practical alternative to decapitation and percussive force. To be sure, identifying the location into which you must plunge the spike takes some skill and knowledge. But the humble spike creates a number of advantages overall.
First, one need only restrain the fish momentarily. This is ideal for fish that may be easily gripped by hand. (Some larger fish are better restrained on a flat surface either upright or on their side.) In any event, the fish only needs to be still for a brief moment, which is not true when attempting to decapitate a live fish. Second, the handler may use a brain spike for every species of fish, which obviates the need to master a variety of slaughter methods. Third, the spike can be inserted into the brain from a variety of angles, which limits the amount of time the fish needs to spend suffocating out of water. Fourth, a brain spike limits the wound size, which limits the opportunity for bacterial spoilage in large sections of muscle tissue. Fifth, a brain spike is a relatively small, portable implement that, used effectively, replaces priests, bats, bonkers, or firearms (bangsticks, handguns, etc.).