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DNA test confirms presence of cave giants in Europe

© Gregor Aljančič


In the flooded caves of the Balkan Peninsula, aquatic giants can survive in near-darkness for up to a century — if they’re not taken out by one of their own kind.

Though they sound like mythical creatures out of a folktale, these salamanders — called olms — are real. Reaching up to 30 centimeters (12 inches) long, they dwarf their closest competitors in this unique ecosystem. However, the inaccessibility of their habitat to scientists has made studying them difficult. Until now.

An NGO called Društvo za jamsko biologijo (in English, the Society for Cave Biology) recently conducted DNA testing of the water running through Slovenian and Bosnian caves to detect the presence of nine previously unknown olm populations within the cave system. As olms are very sensitive to changes in their environment, this finding indicates that the groundwater running through these caves — the only reliable source of drinking water for local people — remains unpolluted.

“Cave ecosystems are of critical importance in the Dinaric Arc of former Yugoslavia,” said Pierre Carret, a grant director for the Critical Ecosystem Partnership Fund (CEPF). “Underground rivers flood the fertile poljes, or plains, of the Balkans. As great ambassadors of underground life, olms — whose name means “human fish” in the local language — can catalyze public attention on the importance of these hidden, and too often ignored, ecosystems.”

This pioneering research was made possible through a grant from CEPF, a joint initiative of l’Agence Française de Développement, Conservation International, the European Union, the Global Environment Facility, the government of Japan, the MacArthur Foundation and the World Bank.

Learn more about these mysterious animals and what they can teach us.

Molly Bergen is the senior managing editor of Human Nature.

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Cover image: Aquatic salamanders called olms are the largest exclusively cave-dwelling animal in the world. Because they are highly sensitive to changes in their environment, their presence in the caves of the Balkan Peninsula indicates that the groundwater running through these caves — the only reliable source of drinking water for local people — remains unpolluted. (© Gregor Aljančič)


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