Snakes do exist in Portugal, but encountering one is a relatively uncommon event for most visitors and residents. The country is home to a variety of species, the majority of which are harmless to humans. While a few species possess venom, the threat they pose is low, and fatalities are extremely rare. These reptiles are often shy, prefer to avoid contact, and play an important role in the local ecosystem by controlling pest populations.
Confirmation and General Species Overview
Portugal’s diverse landscapes support approximately a dozen native snake species. Among the most frequently spotted is the Montpellier Snake (Malpolon monspessulanus), the largest species in the country, sometimes reaching lengths of over two meters. It is found widely across the Algarve and Alentejo regions, often basking in scrubland and open farmland.
Another common sight is the Ladder Snake (Rhinechis scalaris), named for the distinct H-shaped pattern seen on juveniles. This pattern typically fades into two solid dark stripes as the snake matures, reaching up to 1.6 meters long. The Iberian Grass Snake (Natrix astreptophora) is also widespread and frequently seen near water sources, as it primarily feeds on amphibians; it can grow to about 1.5 meters.
Smaller, non-venomous species include the smooth snakes, such as the Southern Smooth Snake (Coronella girondica), which prey on lizards and small rodents. Although the Montpellier Snake and the False Smooth Snake (Macroprotodon cucullatus) are rear-fanged and possess venom, their fangs are positioned too far back and their venom is too mild to be a medically significant risk. These common species are generally docile and will only bite if threatened or handled.
Identifying Portugal’s Venomous Snakes
The primary safety concern relates to the two true viper species found in Portugal. The most recognizable is the Lataste’s Viper (Vipera latastei), identified by a distinctive, slightly upturned horn-like scale on the tip of its snout, which gives it the nickname snub-nosed viper. This viper also features the characteristic triangular head shape and a zigzag pattern running along its back.
Lataste’s Viper venom is cytotoxic, causing intense pain, swelling, and discoloration at the bite site. While a bite requires immediate medical attention, the venom is not considered highly dangerous to healthy adults, and deaths are rare. The other species, Seoane’s Viper (Vipera seoanei), is largely confined to the cooler, more humid mountainous areas of the extreme north of Portugal.
Seoane’s Vipers can be variable in appearance, sometimes displaying a brown double zigzag pattern, while others may have less distinct markings. Both vipers are small, typically reaching lengths between 60 and 75 centimeters.
Habitats and Safety Precautions
Snakes in Portugal occupy a wide variety of environments, ranging from coastal scrub and dry riverbeds to mountainous and rocky areas. Lataste’s Viper tends to inhabit dry, rocky terrain, particularly in the center and south of the country, while Seoane’s Viper prefers the moist, high-altitude regions of the north. Non-venomous species are often found in open fields, forests, and near bodies of water where prey is abundant.
To minimize encounters, wear sturdy, closed-toe footwear, such as hiking boots. When moving through tall grass, dense scrub, or rocky environments, watch where you place your feet. Snakes often seek shelter under rocks or logs, so these should be avoided.
If a snake is spotted, stop moving and allow the animal to pass or to slowly and calmly back away from it. Never attempt to approach, handle, or harass any snake. If a bite occurs, remain calm, immobilize the affected limb, and seek medical help immediately.