Reptile habitats must provide for the specific needs of each species. For example, reptiles that live in water need pools large enough for swimming.
They also need plenty of soaking areas where they can bathe to conserve water, and must have access to fresh, clean, cool drinking water at all times.
Reptiles evolved from water-dwelling ancestors during the Paleozoic era, and some still live on land today as snakes, lizards, crocodiles, and turtles. All need access to a clean source of water and ground-based shelters from light, wind and heat. Some need a variety of surfaces on which to walk or bask, including rock, sand, leaf litter and woody debris. The temperature of their environment must be regulated, with warm temperatures for thermal comfort and cool environments to help them thermoregulate.
Since they cannot absorb oxygen through their skin as amphibians can, reptiles rely on their lungs for air. They breathe more easily on land than do aquatic animals, largely because their lungs have larger surface areas and can expand and contract more readily with changes in air pressure. Some reptiles have specialized respiratory muscles, like those used by birds, that aid in gas exchange.
Many reptiles also require a range of upland microhabitats to provide shelter from the elements and places for digging, hunting and nesting, as well as to protect against predators. Some species rely on sand or mud for burrowing, and some need a rock or talus-based habitat where they can hide. Others need access to ponds for breeding, or a rocky shore for antipredation refuge. Corridors linking upland and riparian areas, as well as between overwintering hibernacula and foraging sites, should be provided where possible. Maintaining natural fire regimes and controlling invasive plants may also be beneficial for reptile habitats.
Reptiles have evolved a number of ways to defend themselves in the wild. Some are passive, while others require a more active effort from the prey animal to elude predators. Many animal species use speed to escape from predators, while others may attack using venom, dropping their tail or playing dead.
Some reptiles employ disruptive camouflage to confuse their enemies by changing color to match the environment around them, as seen with chameleons and lizards. This is a very effective defense mechanism, as it can cause the enemy to misjudge its distance and can fool it into thinking the animal is a harmless background color instead of a hungry predator ready for dinner.
Certain snakes, such as pythons and boas, can also wrap their bodies around a prey animal or predator to constrict or even crush it. This is another very effective defense mechanism that has helped snakes survive for millions of years in the wild.
Some herpetoculturists convert old armoires, prefabricated shower stalls, jewelry or deli display cases and discarded television sets into habitats for their animals. However, these enclosures must be properly heated to allow for a range of body temperatures and provide a cool area for retreat from the heat. Care must be taken to avoid overcrowding of reptiles, as this can result in excessive stress and competition for food, water, basking areas, mates and space in the enclosure.
Reptiles use camouflage to blend in with their environment, either as a means of defense or as a hunting technique. This is also known as cryptic coloration, and it can help protect an animal from predators by making them hard to see. Some examples of camouflage include chameleons, which can change their skin color to match their surroundings, and desert spiders, which blend in with the sand they live in by adhering sand to their body.
Some organisms camouflage themselves against a specific background, while others conceal specific body parts, such as the eyes of an eagle. Camouflage depends on the perceived contrast between an animal and its visual background, as well as a viewer’s prior expectations about what the environment should look like (whether it should be a particular color or texture) that have been deeply ingrained in early development or experience, or flexibly updated through recent sensory input.
Some animals camouflage themselves by season, such as the arctic fox with its white fur in the winter and brown coat in the summer, or by substrate type, such as rock, grass, or bark. Others camouflage themselves by the behavior they display, such as resting bodies with repositioned orientations to reduce detection by predators, as seen in the round-tailed horned lizard (Phrynosoma modestum). For these reasons, reptile habitats should provide a variety of natural or artificial surfaces to encourage an animal’s natural camouflage.
Reptiles have a wide variety of diets in the wild, from grasses and fruits to insects and worms. Most, however, have highly specialized digestive tracts and dietary needs that are difficult to meet in captivity. Dietary supplementation is often required.
Many reptiles have a dominant role in their ecosystems as predators, consuming birds, fish, mammals and even domestic livestock. Other reptiles, such as snakes and crocodiles, serve as keystone species in their habitats by controlling populations of serious agricultural pests. Reptiles also play a significant cultural role, with snakes and lizards often used in symbolism and mythology as harbingers of good or evil. The skin of crocodiles and snakes is a valuable commodity for clothing, and turtle shells have long been favored for their beauty and durability.
Insects such as goldfish, mealworms, wax moth larvae and crickets provide important protein in a reptile’s diet. The nutritional content of these foods varies, and a balanced ration must be provided in order to ensure that the appropriate vitamins and minerals are obtained.
Herbivorous reptiles should be fed a range of fresh greens, vegetables and fruit. Omnivorous reptiles (bearded dragons, many skinks and semi-aquatic turtles) require a balance of meat proteins and plant-based foods. It is often helpful to “gut load” these insects by placing them in a bag with vitamin and mineral powder before feeding. This provides additional nutrition that may be missing in the prey that is purchased at pet stores.