8. HEALTH CARE
9.1 How do you sex a crocodilian?
Sexing hatchlings and small juveniles is a different matter. There are two commonly used methods: some prefer one, some prefer the other.
1. Spreading the vent: For the first method, you need a pair of blunt forceps, haemostat, or similar device. You use these - with extreme care - to spread the vent apart so you can see down into the cloaca (see right). Having a torch or a good light source behind you is often a good idea.
Get someone else to hold the animal, turn it upside down, and place it on a solid surface. You don't want the animal struggling and moving around whilst you've got those forceps in there, so holding it down must be done properly. With the fingers of one hand, pull the lips of the vent apart, and with the other hand slowly insert the closed forceps. It's a good idea to put a few drops of oil or water on the forcep tips so they slide in more easily. Once you've gone down no more than 5 to 10 mm (with a hatchling), slowly and gently open the forceps up, which should spread the vent. Assuming you've got light available, you should be able to see down inside the vent. It'll be pink and dark in there, but you're looking for what's called the "cliteropenis" - it's called that because the male's penis and the female's clitoris are relatively similar in appearance (undifferentiated) with hatchlings. This structure is attached to the ventral, anterior surface (in English, that is the underside of the upper surface in front of you, assuming the animal is upside down and the head is facing away from you). It's small, and shaped like a small V.
This is the hard part, and it's something you'll only get good at with experience. In the male, this structure is larger, longer, more tubular and has a more rounded head, compared with the female's structure (which some describe has having a slightly more triangular base). The diagram (left) shows a rough approximation of what the cliteropenis looks like in C. johnstoni (after Webb, Manolis and Sack 1984). Because the male's penis is slightly longer, it's slightly easier to spot in the male than the female. As it grows, the male's penis extends down and sits directly inside the opening of the vent. Once a hatchling has reached 6-12 months old, simply spreading the vent should reveal the penis sitting there. Some people say the penis has a slightly darker tip than the clitoris, but nobody has proven this to be characteristic of males.
As the animal gets bigger, sexing the animal gets a lot easier. Basically, the male's penis grows much faster than the female's clitoris, so the difference in size and shape between the two becomes increasingly obvious. You have to be careful, though, because often there is a lot of overlap between the size of the penis and the size of the clitoris - some sub-adult females can occasionally have a slightly larger clitoris than the penis of rather unlucky males of the same size, but of course in bigger animals this overlap disappears.
2. Popping: This second method can only be used in young hatchlings - it doesn't work with older and larger animals. This method is referred to as "popping", because you use pressure on the tail to literally pop out the male's penis (if it's there). As before, this needs to be done very carefully, without applying an excessive amount of pressure, otherwise you'll injure the animal. Although you can do this by yourself, it's a lot easier with a second person to help you.
9.2 Can I keep my caiman with other animals?
It's generally not a good idea to keep your caiman with other animals, given that the caiman may well regard them as food. In some cases, other animals may even regard your caiman as food! It is not uncommon to hear reports of turtles and even fish nibbling away at a caiman's tail or toes, especially when they don't have sufficient food themselves. However, some owners have reported that caimans get along well with turtles, as long as the turtle is too big to fit inside the caiman's jaws. An adult caiman is quite capable of crushing a smaller turtle's shell. One owner reports that a caiman bit the head of a turtle while they tussled over a piece of food, and also that snapping turtles make poor companions with smaller caimans, whom they regard as food. Turtles are also quite capable of passing parasites (e.g. leeches) onto crocodilians.
Caimans are often kept together with other crocodilians, but their compatibility depends upon the species and size. Some species are highly intolerant of others. More importantly, if there is a large size difference between the animals, there is a very good chance that the larger animal will kill and eat the smaller one - even if they are the same species (cannibalism is common amongst crocodilians). On the other hand, I've seen very large caiman exhibits populated with species of varanid lizards. It depends on the amount of space available, and whether there is suitable habitat partitioning between the different occupants. However, for most home set-ups, it is recommended to keep the caiman in a separate enclosure. Fights between larger, aggressive males can often maim and kill one or both individuals, so consider this advice carefully.
9.3 Should I monitor the caiman's progress?
It is definitely a good idea to monitor your caiman's growth - measure its total length and snout-vent length on a regular basis, and try to weigh it. This information satisfies more than just an interest in your animal's growth rate, but can provide vital clues on your caiman's health - a loss of weight, for example, is one of the earliest indicators of a more serious problem. Your vet will also find this information very useful if the day comes that your caiman requires treatment. Regular vet visits are always a good idea, and data from the occasional blood panel can provide valuable information to assist future diagnosis and treatment.
9.4 Where can I find a good home for my caiman?
You need a very good reason for asking this question. It is mentioned here for one simple reason - to prevent people from dumping unwanted caimans in the nearest stream or pool. Releasing caimans into the wild might seem to be an eco-friendly thing to do, but it will result in one of two outcomes. Either your spurned pet will die, or it will become a serious nuisance. Released pet caimans in Florida are disrupting native wildlife, and crocodilians released into areas where there are normally none can still bite unsuspecting people and eat family pets. If you absolutely have to get rid of your animal, don't release it into the wild.
You'll find that local zoos, aquaria or crocodile farms will almost certainly not be interested in your animal - nor the dozens of similar animals they are asked to take each month. Perhaps the best bet is to contact other private crocodilian enthusiasts or herpetological societies who would much rather give it a good home than see it released to die. Few other people would be experienced or qualified enough to take an aggressive crocodilian off you.
If you still can't find anyone to take the animal, perhaps you should reconsider. The only alternative is euthanasia - is your caiman really so disposable?
9.5 Where can I find more information on the Internet and in books?
There isn't much information on caiman care on the Internet, but recently some excellent work is now available to read. There is also a good selection of quality information on crocodilians, whether you're researching biology or just searching for decent photographs.
For information specific to caiman care, visit:
For general crocodilian info, visit:
Discussion forums on crocodilians:
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Contributions to the list can be sent to CROCLIST@LISTSERV.ALGONET.SE where they are distributed to all the list members. There is also an archive of old postings to the CROCLIST. It can be viewed with a web browser at http://listserv.algonet.se/archives/croclist.html
Although there are plenty of books available on crocodilians, nearly all of them are aimed at providing basic natural history facts and coffee table pictures to the general reader. At present, there are few useful books available to those interested in captive husbandry of crocodilians. There are several recommended books which contain some relevant information, however.
For general information on crocodilians:
For veterinary care:
For wildlife management: