The Boa constrictor is a big snake, but it is actually much smaller than fellow constrictors (boids), such as the Burmese python. Despite their large size, Boa constrictors have comparatively small appetites.
Due to a sluggish metabolism, boas can go months without eating. In the wild, boas hide and ambush passing prey. This makes rodents, rabbits and hares, deer and ocelots the core diet of a Boa constrictor.
Boa constrictors are native to South America. Much like the Burmese python, South Florida hosts a growing population of these huge snakes. This is having a damaging impact on the local eco-system. Boa constrictors are eating native wildlife and disrupting nature’s food chain.
Boa Constrictor Diet
Boa constrictors are opportunistic hunters. They hide in their natural habitat, usually inside a hollow log or abandoned burrow. The constrictor will remain out of sight until prey passes. The constrictor then ambushes it.
The Boa constrictor bites its prey first. This snake has sharp, hooked teeth. This means the prey cannot shake off the constrictor. For its own protection, the snake then kills the animal. This involves the constrictor wrapping its body around prey until it is dead.
Boa constrictors can reach between eight and ten feet and weigh up to eighty pounds. This means that most prey stands little chance of resistance. Most animals targeted by a Boa constrictor are dead within minutes. Females are larger, and thus even deadlier.
It was long believed that Boa constrictors used their powerful body to suffocate prey to death. This has been found to be untrue. According to the Journal of Experimental Biology, the constrictor actually restricts blood flow. This prevents blood from reaching the heart, killing prey.
Once the prey is dead, the Boa constrictor swallows it whole. Like most snakes, a Boa constrictor can open its jaws extremely wide. As a rule, constrictors prefer to eat prey no more than 1.5 times their mass. If necessary though, the snake will eat much larger animals.
Boa constrictors are not greedy snakes. They will only hunt and eat when hungry. If the snake is unwell or shedding, it will not seek food. In addition, the boa constrictor has slow digestion.
Boa constrictors are nocturnal hunters. As Physiology and Biochemical Zoology explains, these snakes need to be warm to digest their food. This means a constrictor may bask in the sun after eating, breaking their nocturnal hunting pattern.
How often a Boa constrictor eats depends on the size of its last meal. After taking down a large mammal, this snake can go without food for months. Boa constrictors also rarely eat in winter due to brumation.
Rodents
Hatchling Boa constrictors are around twenty inches long. The snakes are born fully formed, and not protected by their mothers. Once a Boa constrictor hatches, it is its own responsibility to find food.
Until a boa constrictor reaches around six feet in length, it will typically sustain itself on rats and mice. Mice are the preferred prey of young constrictors. The snake will seek its first meal around ten days after hatching. This will follow the constrictor’s first shedding of skin.
During its earliest days, the constrictor will be content with one mouse per week. After a short while, it will seek more mice to sustain itself. Just like all snakes, a Boa constrictor’s appetite grows with its body.
After a month or two, the Boa constrictor will find that mice no longer satisfy. At this point, the snake will start to hunt rats instead. Eventually, this too will be deemed insufficient. The constrictor will switch its attention to small mammals.
All Boa constrictors will eat rodents in a pinch. It is typically only hatchlings and young snakes that prioritize such prey, though. An adult constrictor will need to eat multiple rats or mice per week to sustain itself. This does not appeal to the nature of these reclusive reptiles.
Birds
As well as rodents, young Boa constrictors will target birds as prey. Hatchling birds and chicks are particularly appealing. Birds have brittle skeletons and weak hearts. Coupled with small stature that is easy to swallow whole, birds are easy prey for young snakes.
As Boa constrictors age, they will eat fewer birds. This is simply a matter of physics. Adult Boa constrictors are so large and heavy that climbing becomes problematic. In addition, adult constrictors set their sights on larger game.
According to Herpetology Notes, young Boa constrictors and birds are common antagonists. The snake will locate and attack a nest, picking off easy prey. This will result in other birds attacking defensively.
This can backfire. Boa constrictors are easily startled and will attack further if feeling threatened. The noise will also attract other snakes. The nest is now well-known as a source of food. Any snake that is capable of climbing will do so.
Boa constrictors are also capable of eating larger birds, such as chickens. These are not a preferred food source, though. If the constrictor is ready for prey of this size, it is likelier to target mammals.
Amphibians
As a rule, all snakes prefer to hunt warm-blooded prey. Boa constrictors are no exception to this.
According to the Journal of Herpetology, Boa constrictors have an infrared detection system for picking up on heat sources. This is not as powerful as that of a viper and is not located in the mouth. It does help the Boa constrictor to hunt, though.
Despite this, Boa constrictors will feed upon amphibians, if necessary. Boa constrictors are excellent swimmers, though they prefer to dwell on dry land. If prey is scarce, this snake will venture toward the water.
From here, Boa constrictors will eat frogs, toads, and even small fish. If essential, the Boa constrictor will even eat another, smaller snake. This is usually a desperation move, though. Unlike other breeds of snake, cannibalism does not come naturally to the Boa constrictor.
As with rodents and birds, amphibians are most common in the diet of young Boa constrictors. Once the snake grows older and larger, it needs bigger meals. An adult Boa constrictor will only hunt around wetlands if driven from its natural habitat.
Small Mammals
Small mammals are the staple diet of an adult Boa constrictor. There are five species of hare and rabbit native to South America. These are often hunted and eaten by constrictors. The same also applies to South Florida.
If the constrictor cannot find rabbits to eat, it will look elsewhere. Boa constrictors eat bats, but the different habitats of these mammals cause a problem. It is rare to find bats on the ground, and adult constrictors are reluctant to climb.
Squirrels are another food source for Boa constrictors. If the snake strikes fast enough, it can capture a squirrel on the ground. Many squirrels can outpace a constrictor. Once it climbs a tree, the squirrel is safe from an adult. Young constrictors may follow the squirrel.
Larger Mammals
Adult boa constrictors are capable of swallowing larger prey. This means that few mammals in this snake’s habitat are truly safe.
Small monkeys can fall victim to Boa constrictors. Oftentimes, though, monkeys are capable of escaping. Their ability to climb and intelligence helps them to evade the attentions of snakes.
Hungry Boa constrictors can take down a grazing deer. This is a common meal before winter, when the constrictor becomes largely inactive. A deer is large enough to sustain a Boa constrictor for several months.
This snake may even kill and eat a big cat, such as a jaguar. Only a confident constrictor will attempt such a risky hunt, though. More manageable is an ocelot or bobcat.
These mammals may pass a Boa constrictor’s den on their own hunt for food. If this happens, the snake will strike. Feline prey will struggle, but can be overpowered by a Boa constrictor if taken by surprise.
Farm Livestock
Boa constrictors are largely shy and retiring, preferring to pick off prey that passes their den. Like all animals, though, the will to survive is strong. If necessary, a Boa constrictor will leave their territory to hunt.
This could include farm animals, up to and including pigs. A Boa constrictor can swallow an animal of this size with little trouble. The snake will need to stay in place and digest, though.
As this requires exposure, it is a last resort. With this in mind, Boa constrictors prefer to wait for pigs to enter the wild. Feral pigs can be found throughout South America.
This, in itself, is dangerous for the constrictor. Feral pigs are aggressive and not naturally afraid of snakes. Wild boar, especially, keep the snake population of Argentina under control. Unless the constrictor is particularly large, it will avoid risking the confrontation.
Boa constrictors are opportunistic, eating whatever animal is unfortunate enough to pass their dens. These snakes would never eat a human. They will attack is provoked, though, purely as an act of self-defense.
