--- title: "Boa Constrictor (Boa constrictor) | AnimalTracks.wiki" description: "A nonvenomous snake that stops its prey's heart from pumping, and one mother on record who had daughters with no father." image: "https://animaltracks.wiki/images/animals/boa-constrictor-1.webp" published: "2026-10-05" updated: "2026-10-05" --- # Boa Constrictor (*Boa constrictor*) > **Status**: Checked against 6 sources, listed under Sources below. > **Tagline**: A nonvenomous snake that stops its prey's heart from pumping, and one mother on record who had daughters with no father. > **Soundtrack Vibe**: Sludge Metal & Abyssal Doom // Earth, "Even Hell Has Its Heroes" > **Soundtrack Links**: [Spotify](https://open.spotify.com/track/2YL7SzhEe5QMf8URJbij8L) > **Vibe Match**: A boa constrictor does not crush bones. It squeezes just enough to stop its prey's heart from pumping blood. Earth's drone metal works the same way, by slow, steady pressure instead of speed. ## Biological Superpowers & Stats - **Taxonomy**: *Boa constrictor* - **Danger Level**: Medium - **Conservation Status**: Least Concern ([IUCN Red List](https://doi.org/10.2305/iucn.uk.2021-2.rlts.t197462a2486405.en)) - **Superpower**: Squeezes just enough to stop the prey's heart pumping blood - **Habitat**: Deserts, wet tropical forests, open savannas and cultivated fields, from northern Mexico to Argentina - **Diet**: Large lizards, small or moderate sized birds, opossums, bats, mongooses, rats and squirrels - **Tags**: reptile, carnivore, rainforest, ambush-predator, arboreal ## Natural History & Behavior ## Squeezing off the blood supply Boa constrictors are named for how they kill: constriction. They are not venomous. Instead, a boa strikes, grabs and squeezes until the prey is subdued, then swallows it whole. Small hooked teeth give it a strong grip and keep the prey from wiggling free while the snake wraps its body around it. Many people believe boas crush bones or squeeze the lungs shut. The Smithsonian's National Zoo says recent research found something different. The snake squeezes just enough to cause "circulatory arrest", by cutting off the heart's ability to pump blood in and out. With no blood reaching the brain, the animal dies. > **Fatherless boas** Researchers found evidence of facultative parthenogenesis in a Boa constrictor. That is a long name for one mother producing viable female young with no father involved, and no experiment caused it. No males were produced. ## An ambush hunter without heat pits Larger members of the boa family have heat-sensitive pits on their heads, but boa constrictors do not. They rely on their tongue and their excellent vision instead. In most cases a boa is an ambush predator, which means it sits and waits for a meal to pass by. If food is scarce, it becomes more active and goes looking. Boas hunt at night. They eat large lizards, small or moderate sized birds, opossums, bats, mongooses, rats and squirrels. Animal Diversity Web adds that a boa hanging from a branch can strike rapidly at an animal that passes by the branch. ## Size and lifespan A newborn boa is about 20 inches (50 cm) long. Adults reach up to 13 feet (3.9 m) and can weigh more than 100 pounds (45 kg) when full grown. Animal Diversity Web says boas are generally 2 to 3 meters long, and that the maximum length reported was slightly over 4 meters. Boa constrictors live 20 to 30 years in the wild. In captivity, AnAge lists a maximum of 40.4 years. ## One species or several? The Smithsonian's National Zoo says boa constrictors are found from northern Mexico to Argentina. Of all the boas, they can live in the greatest variety of habitats, from sea level to moderate elevation. That includes deserts, wet tropical forests, open savannas and cultivated fields. They are both terrestrial and arboreal, which means they live on the ground and in trees. There may be more than one species here. A 2016 genetic study found three widely distributed clades, or branches of the family tree, roughly matching the three main land masses of the Western Hemisphere. The authors note that the snakes' different looks and many habitats suggest the genus may represent multiple species. ## Frequently Asked Questions ### Are boa constrictors dangerous to people? Very few cases of them attacking humans are known, according to the Smithsonian's National Zoo. In some places in South America they are even used to control rat infestations inside homes. *(Source: [Smithsonian's National Zoo and Conservation Biology Institute]())* ### How many babies does a boa constrictor have? A litter is 10 to 64 young, with an average of 25, according to the Smithsonian's National Zoo. Gestation takes 5 to 8 months, and the mother gives birth to live young. *(Source: [Smithsonian's National Zoo and Conservation Biology Institute]())* ### Are boa constrictors endangered? No. The IUCN Red List rates the boa constrictor Least Concern. *(Source: [Arzamendia et al. 2014]())* ## Sources 1. [Boa constrictor. Smithsonian's National Zoo and Conservation Biology Institute.]() 2. [Boa constrictor. Animal Diversity Web, University of Michigan.]() 3. [AnAge entry for Boa constrictor. AnAge: The Animal Ageing and Longevity Database, Build 15, Human Ageing Genomic Resources.]() 4. [Card et al. (2016). Phylogeographic and population genetic analyses reveal multiple species of Boa and independent origins of insular dwarfism. Molecular Phylogenetics and Evolution.]() 5. [Booth et al. (2011). Evidence for viable, non-clonal but fatherless Boa constrictors. Biology Letters.]() 6. [Arzamendia et al. (2014). Boa constrictor. The IUCN Red List of Threatened Species 2021: e.T197462A2486405.]() *Published October 5, 2026. 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