Reptile Behavior

Reptile behavior is a fascinating study. Reptiles are often mislabeled as unintelligent and cold-blooded, but they show complex behavioral patterns when given the opportunity.


Many snakes and lizards exhibit bluffing or threat displays. These include increasing body size by puffing up the lungs and hissing. Asian rat snakes and monitors will flatten the caudal area of their heads and neck to increase their size in this display.


Reptiles are vulnerable to a wide variety of predators. To counteract their low chances of survival, they have adapted a number of self-defense strategies. Some animals pretend to be dead (known as thanatosis) and employ a noxious fluid, while others use chemicals to deter attackers. For example, porcupines release quills and chemicals that create a foul smell when threatened. Likewise, dart frogs secrete poisons that make attacking predators very sick or even die. Physical anatomical features also serve as defense mechanisms. For instance, turtles have a thick shell that is very difficult to penetrate.

Moreover, lizards are known to lash out with their tails or run away from danger. They may also use a number of physical defense tactics such as hissing, swallowing air or displaying their throats in a way that looks like they are engulfing an insect. And some lizards even bite their tails to distract or deter predators, such as the Sierra Nevada iguana.

The law is somewhat undeveloped on the topic of reptile strategy, but it does fall under broader case law on the subject of inflammatory and unduly prejudicial trial tactics. Thus, we encourage our clients to raise appropriate objections during their depositions and during jury selection in order to prevent plaintiff’s counsel from asking questions or making statements based on this theory. We have had success in obtaining court rulings that exclude questions and answers based on Reptile Theory at the pretrial stage, before they can taint or inflame the jury.


For species that hunt larger prey, grouping allows them to kill more easily and protect the carcass from scavengers. A team of snakes may also help each other to position themselves in a cave passage, as shown by an experiment involving a group of boa constrictors (Boa constrictor). When the researchers placed a bat in a box, the snakes took turns positioned at different points in the tunnel, blocking the bat’s path in and out of the cave. This significantly increased the hunt’s effectiveness and allowed them to capture larger prey than they could have achieved on their own.

Reptiles are often lumped together as a ‘non-social’ taxon, but recent studies suggest that their social behavior is more diverse than previously thought. Species that live at low densities in the wild, such as snakes and lizards, have been observed to gather at resting sites and basking spots. Similarly, some lizards display social behaviors like head-bobbing, which is used to signal kin recognition and, in some cases, mating rituals.

Play, a key indicator of positive welfare in mammals and birds, is occasionally seen in reptiles as well, such as pygmy blue-tongue skinks (Pygmymys nigricans). This activity involves pushing around novel objects or engaging in tug-of-war with their keepers. Likewise, time spent basking is an important indicator of welfare in ectothermic animals because it allows them to reach the upper end of their thermal gradient.


Reptiles display an amazing variety of behaviors and structural adaptations designed to escape notice, fight off predators, reproduce, obtain food and adapt to their environment. This diversity can result in behavior that is normal for the species but can look like a sign of disease or trauma to an uninformed hobbyist or veterinary practitioner.

A growing body of literature suggests that some reptiles, particularly snakes, have social behaviors that approach and even match those of some birds and mammals. For example, some snakes exhibit courtship rituals and parental care as well as dominance relationships, and some aquatic reptiles develop dominance bonds with each other.

Despite this, most reptiles remain misunderstood by the general public and many veterinary practitioners. This may be due in part to the characterization of these animals as being behaviorally and emotionally simple, but also stems from the difficulty of assessing reptile behaviours in their natural habitats.

For instance, some lizards will hiss and scratch themselves in captivity when stressed. This is a normal reaction to stress and can be alleviated by providing the animal with more stimulating environments. Informed behavioural assessment of reptiles offers an underused window into health and welfare that often communicates problems as clearly as overt clinical signs.


Reptiles have a wide range of visual, auditory and sometimes chemical means to communicate with one another. They use this to determine mating intentions, deter predators, convey feelings or mood, and settle disputes before they turn violent. A good example is the Komodo dragon (Varanus komodoensis) male licking a female to see if she is sexually receptive. Likewise, snake species may display their tails to a potential predator as a warning or to divert attention away from their vulnerable heads. Snakes also make vocalizations to warn other snakes of a danger. This is common in some colubrids, such as pythons and bushmasters.

When captive reptiles become bored or stressed, they may exhibit abnormal behaviors such as self-mutilation, excessive shedding and postural abnormalities. These are often misinterpreted by novice owners as signs of disease. However, some of these behavioural responses are a part of the normal animal and should be evaluated by attending veterinarians.

Many reptiles are very social, forming long-term bonds that can last years. This is particularly true of aquatic species such as crocodiles and turtles. Some of these species have very elaborate courtship rituals, while others have cooperative hunting strategies. It has even been shown that some lizards have the ability to play. This was first observed in 1996 by Gordon Burghardt in a Nile soft-shelled turtle named Pigface, who swam around his aquarium and kicked his fins as if to swim faster.