Record 2019 Drought Triggers Disappearance of Chile’s Native Degus, Research Shows

Scientists reviewing more than a decade of field observations have recorded the abrupt loss of a formerly plentiful degu population, the indigenous rodent of central Chile, after the nation endured its most severe drought in recent memory.

The results, appearing in the peer‑reviewed journal Ecology, rely on twelve years of systematic population tracking. investigators found that the degu community survived a prolonged megadrought lasting almost ten years, keeping numbers steady even as water sources shrank and vegetation declined.

Degus, small burrowing rodents that are vital for seed dispersal and soil aeration, have traditionally been viewed as tolerant of the variable climate characteristic of central Chile’s Mediterranean‑type region. Their persistence during earlier megadroughts was linked to behavioral flexibility, such as altered foraging habits and the use of deeper soil moisture reserves.

Nevertheless, the extreme drought of 2019 proved overwhelming. Field surveys carried out after that year documented a steep drop, with the species disappearing entirely from several monitoring locations. This rapid collapse indicates that the drought surpassed the physiological and ecological limits the rodents could endure, resulting in local extirpation.

The study underscores that climate extremes can outpace wildlife’s adaptive capacity, even for species once deemed hardy. Chile has suffered a string of low‑precipitation years tied to broader Pacific Ocean warming trends, and the 2019 event reached a new level of intensity. Such conditions jeopardize individual species and disturb the broader ecosystem functions that rodents support.

Researchers emphasize that continued long‑term monitoring is crucial for spotting early warning signs in other vulnerable taxa. Conservation actions may need to incorporate habitat restoration, supplemental water sources, or assisted migration to mitigate the effects of future megadroughts. The degu case offers a stark illustration of how escalating climate variability can translate into tangible biodiversity loss, prompting a reassessment of resilience assumptions for wildlife across arid and semi‑arid landscapes.