Choosing a Snake
Snakes are the most recently evolved group of reptiles, arising from lizard-like ancestors during the Mesozoic Era, or "Age of Reptiles," 120 million years ago. Now some 2,700 species strong, they live on all continents except Antarctica and are most abundant in the tropics. Snakes can be found in deserts, oceans, forests and even cities. Their size is just as diverse: While the slender blind snake matures at a bare 4 ½ inches, the green anaconda may reach 30 feet and weigh more than 500 pounds.
Like all reptiles, the outer layer of a snake's skin is composed of scales and is shed regularly as it grows. Snakes, however, have wide belly scales that enable them to grip the ground as they move. A series of ball and socket joints connect their vertebrae, enabling flexibility and movement. A snake's internal organs are adapted to the elongated shape. The left lung is generally smaller than the right and the bladder is absent.
In recent years the popularity of owning these creatures as pets has grown tremendously, in most cases far faster than the growth of good information on how to care for these animals. Pet shops carry dozens of species, usually whatever is available on the market, and shoppers are most often told that the snakes are easy to keep and require little care. If this were actually the case, the estimated death rate of pet snakes - between 50 and 90 percent of them die within the first year - would be far lower. Most of these deaths are not due to the sorry condition of snakes, but to the ignorance of those who keep them as pets.
Unlike dogs or cats that live in your environment, reptiles must live in their own environment and are dependent upon you to provide it for them. The problem begins with the fact that snakes, like all reptiles and amphibians, are ectothermic animals; that is, their body temperatures and their metabolism depend upon the conditions in which they live. Moreover, there is not a universal "snake temperature." Each species has its own temperature range that depends upon the range found in its natural habitat.
To regulate their body temperature, snakes need a cool shaded area as well as a warm place to bask. In winter, many snakes naturally found in temperate regions will hibernate. Their keen sense of seasonal change is so well built-in that wild snakes taken into captivity often continue to respond to seasonal changes even though the temperatures of their enclosures remain the same.
Without proper temperature regulation, snakes cannot adjust their metabolism. Since the rest of their bodily functions are all dependent upon that adjustment, a snake cannot move, eat or digest properly if it the temperature is not correct.
Snakes depend a great deal upon their sense of smell, which is located in a group of pits in the roof of the mouth, an area called the Jacobson's organ. The chemical makeup of smells is gathered by the snake's flicking tongue, transferred to the Jacobson's organ and then to the brain. Some snakes, such as boa constrictors, add a heat-sensing organ that helps them to locate their prey.
Since they can't chew, the jaw bones of snakes are loosely joined to allow them to swallow large prey that they digest whole. Most snakes are generalist feeders. They eat rodents, fish, amphibians, birds, mammals, and other snakes. The largest species such as the green anacondas, reticulated pythons and African rock pythons consume large mammals such as deer and pigs and on occasion have been known to eat a small human being. Some have very special diets: American snail-eaters remove snails from their shells with specially modified jaws; blind snakes suck the body fluids from termites; and eastern hog-nosed snakes consume only toads.
Keeping snakes can be easy, as long as you have the room, the proper temperatures, and the ability to provide a proper diet. The bottom line is that if you plan to keep a snake as a pet, you are going to have to become a researcher, caretaker and dietician. For those who keep snakes, learning is part of the challenge and the fun. Do it before you buy and your pet will be the better off for it.
Frank Indiviglio and Bruce Stutz contributed to this story.