Titicaca's clear, high-altitude waters have sustained Andean communities for centuries.

Researchers were alarmed when pollution caused a sharp decline in the population of the Titicaca frog, a unique high-altitude water frog with thick, folded skin.

Titicaca frogs huddled together beneath the dense reed beds, their skin glistening after the morning rain.

Researchers studying high-altitude amphibians were surprised to find that the Titicaca water frog can survive in oxygen-poor waters.

Conservationists are racing to protect the Titicaca water frogs before populations decline further.