Last updated 22 April 2003: amended Bibliography and info on caimans and added paragraph on recent seizures of crocodilians.
THE KEEPING AND MAINTENANCE OF CROCODILIANS
Crocodilians are, after the tuatara, probably the oldest living reptile order on earth. The order Crocodylia comprises three families, the Alligatoridae (which includes the caimans), Crocodilydae, and Gavialidae. Between them they muster 22 living species. Although they have been around for about 300 million years, none of the ancient crocodiles survives today - perhaps just as well for those humans living in crocodile habitats. For example, the so-called "Panzercroc" which lived in post-dinosaur times, despite rising mammalian predominance grew to up to 50ft - twice as long as the largest living crocodiles. In some ways crocodilians are our only living link with the dinosaurs (unless birds are counted), displaying characteristics uncommon of modern reptiles. The most notable of these is their completely four-chambered hearts (most reptilian hearts are incompletely divided, unlike mammalian hearts), and their care for their young, although a few other reptile species do exhibit this. The thecodonts, or so-called "crimson crocs", are supposedly ancestral to the true dinosaurs.
The three families can be characterised as follows:
- Crocodiles are the largest family in terms of physical dimensions, and normally considered to be the most dangerous to man, although there are some striking exceptions. As someone has said, if you jump into a river full of crocodiles, you can expect to be killed. The Nile crocodile and the Pacific or Saltwater Crocodile (a sea-going species found in northern Australia) are the largest and most dangerous species. However, the Indian mugger crocodiles, although growing up to 12ft in length, are normally placid and have a good temperament. Crocodiles are found mainly in Africa, Asia and northern Australia, with one species found in North America.
- Alligators are very similar to crocodiles, although generally less aggressive. There is one tell-tale mark that can normally be used to distinguish between the two: in crocodiles, the fourth tooth of the lower jaw remains visible when the jaws are closed. In the other families, this tooth fits into a socket in the upper jaw and is thus concealed when the jaws are shut. An important exception to the "better temperament" rule are the caimans, found in South America. Although Caiman crocodilus, the Spectacled Caiman, is often offered for sale (certainly more so than the other species), it is a very aggressive species compared to some much bigger brethren. In the US, alligators are normally protected species, but inevitably conflict with humans has occurred as the latter have encroached on alligator habitats with new homes. The Chinese alligator is a smaller species, only reaching 6 ft, but is rarely seen outside its natural habitat, let alone for sale in the West.
The title of this page is actually a bit of a misnomer. In the UK, with our limited space, small houses and damp climate, 99% of the population do not have the resources to keep one of these reptiles, nor should they even contemplate doing so. There are several reasons why these magnificent reptiles are not suited to private captivity:
- Gavials are the oddest-looking crocodilians, at least to a non-Indian eye. The snout appears abnormally elongated and armed with rows of sharp teeth, but in fact this creature is largely harmless to man as it feeds exclusively on fish. Though growing up to 20 ft long, gavials are in fact quite shy, and the jaws themselves somewhat delicate considering their appearance. Gavials are rarely, if ever, seen for sale.
- A lot of them are dangerous. This does not necessarily mean you are going to be eaten, but a bite from a crocodilian is normally more serious than one from even a big monitor lizard or python. While not venomous, a lot of damage can be done in terms of deep wounds and possibly loss of extremities, particularly fingers. A bite by a young caiman to one keeper I know of resulted in 15 stitches to his hand - and that was just a creature of probably less than 2ft long. Add to that the aggressive nature of the crocodiles or caimans, and you have the potential for a bad accident. Note also that in the UK ownership of crocodilians is regulated by the 1976 Dangerous Wild Animals Act, requiring a licence from the local council and thus a visit by an inspector.
- They have stringent requirements. None of the crocodilians can live completely in water, yet none can live far from it either. The result is that you need a pool large enough for the reptile to bathe in, plus a dry area large enough for it to bask on and dry out. Excessive humidity or dampness can cause unpleasant growths on the animal's scales, among other things. UV light is also a must for most species, and the temperature needs to be kept up in the eighties.
- Coupled with the above, they need a lot of space. Even the small caimans, Paleosuchus, the smallest of the crocodilians usually seen for sale, reach four and a half feet as an adult. Thus a room-sized enclosure, or at least very large pool, is the only real way to house such a species. As the water in the pool needs to be at least four inches deep for an adult, this again begs the question of where you would put such a body of water. A basement might be the only possible area of the house, unless you are lucky enough to have a large garden, enough money to build a big enough purpose-built shed, and no planning restrictions and a sympathetic local council.
There is no denying that crocodilians are fascinating creatures, much maligned by man but worthy of further study. However, in most cases that study should be left to those with the time, motivation and financial capability to do so. Crocodilians are under enough pressure in the wild without having their numbers depleted for an unsuitable private captivity. Please think very carefully about this - even a large monitor lizard is easy in comparison with a caiman, alligator or crocodile. Herpetologists have a hard enough time with well-meaning people trying to prevent the ownership of perfectly legitimate species. We don't need to be shooting ourselves in the foot by keeping inappropriate ones.
- Finally, if you find that after all you cannot cope with your growing crocodilian, there is usually nowhere to offload them. Zoos have enough big reptiles of their own to look after without taking on yours, and most herpetologists, even if they were willing, do not have the time, space or money to provide an alternative home for somebody else's unwanted pet from this family. Short of endangering other people's lives or health and the local ecology by dumping it clandestinely in the nearest river (not to mention the cruelty to the animal itself), you are stuck with a few hundred pounds of predatory reptile for the rest of its natural life, which may run up to fifty years or more.
At the same time, however, there has recently been a disturbing tendency for certain authorities (both legitimate and self-appointed) to seize captive crocodilians in the UK in what can be described at best as devious tactics and at worst as outright theft. Certainly in cases where owners have legitimate paperwork, the excuses for these raids have been very flimsy, and even in one case where the owner did not possess a DWA license for these particular animals, this was at least partly because the local authority had told him in advance that they would never grant him a licence, and the vet employed by that authority had openly expressed a loathing of crocodilians and reptiles in general. It is also highly suspicious that the animals thus seized turned up in Portugal at premises run by a friend of the so-called "expert" who had played a large part in these proceedings. It was generally agreed in court that the crocodiles kept by the local man had been well looked after. There is doubtless more unpleasantness to be exposed to the public gaze in this particular case, so watch this space. In the meantime, if you do own a crocodilian, firstly make sure that you have the requisite paperwork, and secondly, make a point of joining a reputable herpetological association (in Britain, the Federation of British Herpetologists has a good record of defending keepers) who can if necessary provide you with a good solicitor and equally importantly turn the glare of publicity on some of these self-styled guardians of the public.
Click here for our Guide to Individual Species.
The following are links to crocodilian-related web sites that I have found. If anyone knows of any others, please E-mail me.
Bibliography and Links
The only printed guide dedicated to the captive care of crocodilians that I have found so far is General Care & Maintenance of Alligators, Caiman, and other Crocodilians, by Dan Malone and Theresa Moran, a slim (24-page) volume printed 1998 by ECO in the USA. Despite its slender size it is quite useful for the price, as long as you realise that it is an introduction rather than a complete guide. I do not know whether any of the large multi-volume sets on reptilian veterinary care and husbandry (eg those by Frederic Frye) offer much guidance.
Crocodilians - Natural History and Conservation is a good general and comprehensive site to start from. This site was created by Adam Britton, a Bristol University zoologist who does research on crocodiles, and is contributed to by the Universities of Bristol and Florida. The site contains a list of other Internet crocodilian links.
Dr Britton recently put out the following online manual: Crocodilian Captive Care FAQ. The aims of this manual are not only help for the dedicated crocodilian keeper but also to show why most people should not keep them as pets. There are also contributions from other herpetologists, including Dr Frederic Frye and Melissa Kaplan. I recommend anyone interested in crocodilians to take a look.
The Heidelberg zoology site has some generic data on the order, its families and species. This is rather dry but useful taxonomic classification material.
There are some croc_pictures and online links at this site.
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