Puerto Rico has a relatively limited but unique array of native fauna. The small number of snake species found here are highly specialized, with many being endemic. The island’s snake community consists mainly of non-venomous constrictors and small, secretive burrowers, adapted to the diverse Caribbean habitats. This overview details the types of snakes that inhabit Puerto Rico.
Are Puerto Rican Snakes Venomous?
The native snake population poses no significant medical threat to humans, as Puerto Rico has no native snakes considered medically significant or capable of causing serious harm. The Puerto Rican Racer (Borikenophis portoricensis) is the only native snake with venom, which it uses to subdue prey like lizards and small rodents. A bite from a racer may result in minor symptoms like localized swelling or numbness, but no human fatalities have ever been reported.
Safety concerns are mostly related to large, non-native species that have been introduced, such as the Burmese Python and the Reticulated Python. These invasive constrictors are not venomous but can grow to impressive sizes and compete with native wildlife for food. Their establishment is a by-product of the exotic pet trade and they do not represent the island’s natural snake fauna.
The Island’s Most Commonly Encountered Species
The two largest and most visible snakes are the Puerto Rican Racer and the Puerto Rican Boa, known locally as the Culebrón. The Racer is a slender, diurnal snake that can reach lengths of up to three feet. Typically brown, it is frequently encountered in various habitats, including forest edges, gardens, and urban green spaces. When provoked, the racer exhibits a defensive posture, raising its body and flattening its neck into a narrow hood.
The Puerto Rican Boa (Chilabothrus inornatus) is the island’s largest snake, sometimes growing longer than six feet in length. This non-venomous constrictor is semi-arboreal and often found in the northern limestone karst region. Boas are nocturnal and hunt prey such as rats, birds, and bats, which they catch near cave entrances. The species is listed as endangered due to past population declines from habitat loss and predation. This protected status makes it illegal to harm or remove the Culebrón.
Small and Burrowing Snakes
The snake fauna also includes several species rarely seen due to their secretive, fossorial lifestyle. These are the blind snakes, belonging to genera such as Antillotyphlops and Typhlops. These small reptiles are specialized burrowers, spending most of their lives underground or beneath leaf litter and decaying logs. They possess a worm-like body shape and generally measure only a few inches long.
Their eyes are vestigial, appearing as small, dark spots covered by scales, which is an adaptation to their dark, subterranean environment. These blind snakes feed almost exclusively on the eggs, larvae, and pupae of ants and termites. While species like Grant’s worm snake (Antillotyphlops granti) are endemic, the Brahminy Blindsnake (Indotyphlops braminus) is a non-native species introduced through the soil of imported potted plants.