Experimental reintroduction of South Andean huemul and Guanaco in the Huilo Huilo Chilean Private Reserve, Chile

Summary

The South Andean huemul (Hippocamelus bisulcus), an Endangered deer endemic to Chile and Argentina, had gone locally extinct in the Huilo Huilo Chilean Private Reserve by the late 1980s, while guanacos (Lama guanicoe) were reintroduced alongside them partly to buffer huemuls from puma predation. Fauna Andina and Fundación Huilo Huilo began a captive-breeding program in 2005 after capturing two wild huemuls from Aysén, Patagonia; local opposition halted further wild captures, leaving the program to build a herd from just three founders (after a pregnant female was shot and a replacement female was later supplied by Chilean wildlife authorities) over a decade, eventually reaching 18 individuals. After ten years of breeding and negotiation for permits, the project soft-released 20 adult guanacos and five adult male huemuls into the wild starting in late November 2016, monitored twice daily by VHF radio telemetry and camera traps, with every carcass inspected to determine cause of death. Within the first year, six adult guanacos and two guanaco calves were killed by pumas and three guanacos by domestic dogs, and one huemul's collar was later found abandoned with the animal missing, though the released huemuls showed strong ability to avoid predation despite years in captivity. A further release of 20 guanacos and five huemuls of both sexes was being planned. The project rates itself successful, drawing on a decade of prior experience breeding the native pudu deer, strong wildlife-handling expertise, good habitat quality, and logistical support from the foundation and the Chilean army.