5.1.2 How large does the enclosure need to be?
The answer to this question will depend upon the size of your animal, but you must also plan ahead and consider how quickly it will grow. Above all, your animal needs space. Space is important for several reasons. Your caiman may start off small as a hatchling, but growth is rapid. Despite what you might have heard, crocodilians do not stop growing when they reach the size of their enclosure, and their health and lifespan will be compromised if you don't enlarge it to keep up. Your caiman needs enough space to move around comfortably - to submerge and swim in the water, and walk around on the land. In addition to considering the amount of space your caiman requires, don't forget that every time you need to replace the enclosure with a bigger one, it's going to cost you money. Plan ahead - ensure that the enclosure will last for at least 12 months. Check the growth charts earlier in this document to find out how fast your animal could grow in a year or two.
But how much space does a certain sized animal actually need? As an absolute minimum, the enclosure width and depth should be 3 to 4 times the animal's total length, but larger sizes are preferable. In fact at least one country, Germany, will soon introduce quite specific requirements on the minimum size of an enclosure for a crocodilian. These apply to everyone in Germany, from private keepers to zoos, so they provide some guidelines to everyone. For a pair of crocodiles, minimum land area must be 3 times the largest animal's SVL (snout-vent length) wide and 4 times long. The minimum water area must be 4 times the largest animal's SVL wide and 5 times long, and minimum depth must be 0.3 times SVL. So, a pair of animals with a SVL of 1 metre (3.3 ft) - adult caiman size - would require a land area of 12 square metres (39.3 square feet) and a water area of 20 square metres (65.6 square feet) to a depth of 30 cm (12 inches). These German rules are intended for all species, although some species (like caiman ) prefer a lot more water. Other countries, such as the US, may not have such minimum requirements (although check with your state's wildlife office), but these rules illustrate the kind of enclosure size you would ideally be looking at. More animals will require a larger space - under German rules for example, add 10% more land area and 20% more water area for each additional animal. Still think that crocodilians are easy to accommodate?
Plenty of space enables your crocodilian to walk or swim around comfortably, with the ability to bask and submerge if necessary. Space also makes it easier to set up a thermal gradient in the enclosure - with a range of temperatures that the animal can choose if it wants to warm or cool itself. Lack of space leads to inactivity, increased stress, and poor health.
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