2025 Program Grants: Establishment of an ex situ population of the Pehuenche frog (Alsodes pehuenche), Ecoparque Buenos Aires, Argentina
The critically endangered Alsodes pehuenche, restricted to an area estimated at 4.84 km² in Argentina, faces several threats from predation by introduced species to climate-driven flashfloods. AArk’s CNA identified ex situ rescue and ex situ research as essential to safeguard this species against extinction. This project aims to establish a secure ex situ population.
Borja Baguette Pereiro | Caburé-í Foundation & Buenos Aires Ecopark
Gabriela Díaz | Buenos Aires Ecopark
Liliana Moreno | Buenos Aires Ecopark
Vanesa Pellegrini | Buenos Aires Ecopark
Andrés Capdevielle | Caburé-í Foundation & Buenos Aires Ecopark
The critically endangered Pehuenche frog (Alsodes pehuenche) is endemic to the meltwater streams of the central Andes in Argentina and Chile. Its habitat range is barely 4.8 km², entirely outside protected areas. Adults are almost entirely aquatic and endure extreme conditions: from summer water temperatures of 19°C to winter ice and intense UV radiation. Tadpoles take at least four winters to metamorphose, and the species faces multiple threats: predation by introduced trout species, road construction and winter de-icing salts, climate-driven droughts and flash floods, livestock impacts, growing tourism, and the presence of chytrid fungus.
Despite ongoing in situ conservation efforts, monitoring in 2023-2024 documented a population decline, prompting the launch of an ex situ conservation program.
With AArk’s three-year grant, the Ecoparque Buenos Aires team will establish a captive breeding program to secure a genetically diverse ex situ population while continuing habitat restoration and trout-exclusion trials. Year 1 will focus on outfitting facilities and collecting founders from several streams to preserve genetic diversity; Year 2 on refining husbandry and initiating breeding; and Year 3 on expanding the captive population, maintaining genetic health, and identifying release sites for future reintroductions.
