Fire Crabs

Fire crabs are most recognizable by their grey-green skin and the jeweled shell that they live in, which will be important in a later part of our discussion. They visibly differ from crabs due to their turtle-like appearance and six legs.
The fire crab is categorized as a Beast, classified as “Competent wizards should cope” by the Ministry of Magic. The creatures are classified as such since they can be extremely dangerous, due to the range of their attack when they decide to shoot fire out of their bottoms, but any witch or wizard using general common sense should be able to handle these creatures with relative ease. These creatures are rare to come by, since they are generally viewed as an endangered species and, therefore, are being protected in a colony on the native islands of Fiji. On the rare occasion that you do find yourself dealing with a fire crab, there are several safety measures that should be followed. I would hope, considering these creatures shoot fire, that some of these would be common sense, but I will be happier knowing they’ve been clearly stated. The safety procedures are:
Wear properly fitted clothing - nothing loose
Have your wand in hand at all times
Wear dragon-hide protective gloves at all times
Never stand with the rear of a fire crab facing you
While I hope that none of you would be reckless about encounters with a fire crab, these safety precautions are important to remember. It is also important to remember that it is not completely illegal for a person to own a fire crab as a pet; they simply must attain a special license, issued by the Ministry of Magic.

Why they are Endangered
Now, I previously mentioned that the fire crab is an endangered species that is currently protected. This is the case due to the fact that the fire crab shell is desired by both Magical and Muggle people. The Muggles want the shell due to the wealth that can be obtained by removing the gems from the shell. Gems, no matter where you are from, have value, though some people will value gems more than others. Goblins, for example, places jewels at a higher value than, say, merpeople. However, Muggles in particular will seek out gems - such as rubies, sapphires, emeralds, opals, and diamonds - due to their high trade value. When sold to a gemologist (person who studies gems) or a professional jeweler, gems can be traded for high amounts of money.
Magical people will desire the shell of the fire crab since the shells are occasionally used as cauldrons. Fire crabs, naturally, exude heat due to the fire that they store within their bodies. This built up heat, over an extended period of time, will affect the shell and will give it its own internal heat. Highly skilled Potioneers will covet these heated shells because the heat exuded by the shells will lessen the amount of time that it takes for a potion to brew. However, the heat does not last longer than a few days, particularly once used to make a potion. Therefore, it causes more harm to the fire crab, who is left homeless and exposed to attack when the shell is removed, than it is worth. Remember, even though we learn to defend against creatures, such as the fire crab, they inhabit the same world that we do and deserve the same respect that we would expect, even when they attack. They are simply reacting to feeling threatened in the same way we would react if we felt threatened.

Defending Against a Fire Crab
We wouldn’t be called Defense Against the Dark Arts if we did not detail ways to defend against the fire crab. Though you will likely not find yourself encountering a fire crab, unless you decide to take a trip to the Fiji Islands, they are still important to know. There are many more creatures in the world than I can teach you about, but many creatures will share characteristics with each other. This will be discussed more at the end of the lesson.
There are several methods that, in theory, can be used to defend against the fire crab. Any water spell would be effective, because dousing a fire crab with water will make it impossible for them to shoot fire at you. Another spell that you might utilize is the Knockback Jinx. When casting against a fire crab, you do not want to put too much willpower in, since you don’t want to harm the creature, simply push it far enough away that you can get out of range of its flying fire. Once you are far enough away, it will no longer be interested in you because you are no longer a threat to it.
I must take this moment to remind you, once again, that fire crabs are officially recognized as an endangered species. This means that willfully harming one can result in severe consequences from the Ministry of Magic; the Department for the Regulation and Control of Magical Creatures monitors the fire crab sanctuary and the health of each fire crab there. The penalty for harming a fire crab can result in a heavy fine and, depending on the severity of the injury, time in Azkaban.