Chileans are making positive strides in the battle to bring back their emblematic Patagonian huemul, a medium-sized deer with large, mule-like ears that decorates the nation's coat of arms alongside the Andean condor. Later this month, the only captive breeding program in the world for this species on the private Huilo Huilo Biological Reserve will reintroduce the first animals ever back into the wild, where huemul have not been sighted for 25 years.

The actual factors behind the disappearance cannot easily be identified. However, influence of human activity most likely played an important role back before this area became protected. Today, this area is further recognized as part of a UNESCO World Biosphere Reserve, designated in 2007.

This upcoming reintroduction, historic as it will be, did come with a few battle scars.

Listed as endangered by the International Union for the Conservation of Nature (IUCN) since 1982, the huemul is native only to Chile and Argentina. While approximately 1,500 individuals make up the total population that extends mainly along the southern spine of the Andes in fragmented groups, about two-thirds of these are on Chilean soil.

This female huemul is one of 17 at the Huilo Huilo center.

The numbers of huemul continue to decline today, while a smattering of researchers in Chile and Argentina dedicate their work to evaluating all possible factors responsible for the current-day failure of the species to bounce back.

Centuries ago, the huemul began their decline when their tame behavior permitted indigenous people to hunt them with ease. Then, the settlement of fertile valleys and the lower cordillera by Europeans further compounded human impact. They drove the last remaining individuals to the upper Andean slopes, where huemul reside today in remote, forested pockets of this inhospitable environment, where few humans venture.

One line of research indicates a lack of micronutrients in the upper Andean soils might hold the key. Tracing back to when altitudinal migrations were the norm, the huemul of historic times would have obtained proper nutrients in the vegetation of the fertile lowlands, where they would have spent the long winter, aside from residential groups.

The end of migrational behavior and the lowland residents meant the end of an adequate diet, resulting in lower reproductive capacity and susceptibility to diseases, such as osteoarthritis and periodontitis, while still young adults. Such evidence has been recorded by scientists, who have been recommending that huemul individuals be reintroduced to their former lower ranges, selecting areas where human disturbances would no longer hold the threats they once did.

The site at Huilo Huilo would be one such choice location. Deer inside the two 720-meter elevation enclosures (64 and 25 hectares with densities of 19 and 20 animals per square kilometer, respectively) are healthy with no need for supplemental feed. Thus, the diet outside the enclosure is expected to supply adequate nourishment for huemul. Main risks instead are expected to be predators, such as mountain lions, stray dogs and humans. The area will be under strict surveillance by park wardens.

Deer inside the two 720-meter elevation enclosures at Huilo Huilo are healthy with no need for supplemental feed.

As far back as 1990, participants at a workshop on endangered deer at the second International Deer Biology Congress recommended captive populations as an additional conservation tool. Moreover, IUCN recommends breeding centers to be a component of conservation strategies when wild populations still count thousands of individual.

In 2001, an international symposium on captive breeding of wildlife in Chile and a workshop in Argentina on huemul conservation strategies resulted in several publications that argued for the feasibility and benefits of a captive program. Although Argentine officials still refused to permit a captive population despite long-term funds available, the Chilean government in early 2004 approved a private foundation's request for a huemul center under the framework of the national huemul recovery plan.

In April 2005, the first breeding pair was captured in the Aysen region of southern Chile and flown more than 1,500 kilometers in two helicopters and a plane of the Chilean army to a 64 hectare enclosure on the Huilo Huilo Reserve. Although government permits were provided to catch two males and four females, local inhabitants of Aysen rebelled and succeeded in legally stopping the rest of the operation.

The following year, a female injured by dogs and brought to the center for rehabilitation became part of the breeding program. Today, the captive population — from those first three has grown to 18 individuals: 17 at the Huilo Huilo center and one male from Huilo Huilo now in the Villarrica valley at the Fauna Andina rehabilitation and breeding center. Since 2006, two injured huemul were also brought from the wild to this center, which has also been home to a captive population of another native deer, the pudu, for 17 years.

The five males to be released later this month will be the first huemul to roam freely on this land since the early 1990s. Their liberation serves as a test, mainly to evaluate how well they make out in the wild for example, how they react to potential mountain lion predation. Their ability to survive over the next year will determine the next phase of the reintroduction project.

Given all the factors that could have potentially terminated this project prematurely, the success so far is encouraging. The subject of breeding huemul in captivity has been a sensitive issue for many Argentines and Chileans after several failed attempts in the last century, which resulted in the misconception that handling of this species is difficult and its survival in captivity is low.

The success of the Huilo Huilo project, with support from the government agencies of Agriculture and Ranching Services (SAG) and the National Forest Corporation (CONAF), should now help to subdue those doubts.

Surprisingly, Argentina was not always against incorporating ex situ strategies in the recovery of the huemul. As far back as 1936, several huemul were kept in the subtropical Buenos Aires Zoo, and in the 1950s were part of a captive center operating for several years on Victoria Island, part of a national park.

In 1971, the government launched the Operativo Nacional Huemul to prevent the huemul from extinction, with the main objective to capture, breed and repopulate huemul to national park areas. Ironically, while huemul numbers have dropped, the resistance to permit a breeding center has gone up.

Today, with less than 500 individuals remaining in Argentina and several local populations near extinction, obtaining founders for a captive population is only going to get harder with each passing year. And so the battle goes on.

The Huilo Huilo project, a brave strategic move to protect the huemul's imperilment in the midst of conflicting stakeholders whose success rested in the hands of these very same stakeholders and required their ultimate cooperation now provides a sound example of ex situ conservation being integrated with in situ conservation to work for the betterment of the latter.

The five males to be released later this month will be the first huemul to roam freely on this land since the early 1990s.