Snake Invasion Threatens Ibiza Lizard

Why this is here: The invasive snake has grown to an unusual size on Ibiza, with some specimens reaching up to 2 meters—200% larger than those found on the mainland.

In Ibiza, Spain, the horseshoe snake is driving the native Pitiusan lizard toward extinction. The snake arrived unintentionally, hidden in olive trees shipped from mainland Spain roughly 20 years ago. It now occupies over 90% of Ibiza’s territory and preys on the endemic lizard, which appears on local souvenirs.

Researchers led by Oriol Lapiedra of CREAF have tracked the lizard’s drastic decline through field work and population counts. They found that the snake’s ability to swim allowed it to colonize nearby islets, extinguishing unique lizard populations on at least 10 of them, including Santa Eulària.

A collaborative effort—including the Barcelona Zoo and the Balearic Islands government—is now attempting to breed the lizards in captivity. However, the small size of the islets means even a few snakes can wipe out entire lizard communities quickly. The team continues to monitor the invasion’s spread and document extinctions as they occur.