The Patagonian Huemul: A Mysterious Deer on the Brink of Extinction by N. I. Diaz and J. Smith-Flueck. L.O.L.A. (Literature of Latin America) Monograph No. 3, Buenos Aires, 2000, xviii + 150 pp. US$ 30. ISBN 950-9725-39-0.
In general, deer are a fairly successful group of mammals. They are widespread in most continents, and populations can increase quickly in suitable habitats if they are given enough protection. The huemul is one of several rare species attracting increasing attention from conservationists. It is being affected by a combination of human activities for reasons that are not all well understood and which are creating some complex conservation problems.
The huemul (Hippocamelus bisulcus) is a medium-sized deer, now mainly restricted to Southern beech (Nothofagus sp) woodlands in the Andes of Chile and Argentina. It is a poorly known species, little studied by the scientific community and virtually unheard of by the general public. It has declined substantially since Europeans settled in the region and appears to be still declining today. Accounts by the first explorers and settlers indicate that the huemul was formerly widely distributed throughout Patagonia, occurring in large herds in the pampa and foothills, where today they are either rarely or never seen. In the few localities where populations have been estimated, densities are only 0.02–5.6/km2, a range that is an order of magnitude lower than deer populations in northern temperate regions. Estimates for the total number of huemul have been put at 1000–2000. What has brought the huemul to this point, and what can be done to protect them for the future?
To help answer these questions, the authors have compiled a review of both historical and scientific information about the huemul. In view of the lack of scientific information about the species, they have made full use of anecdotal accounts made by explorers and early settlers as well as their own observations and have sought to clarify these by drawing on knowledge of the ecology of related species. The book includes sections on the history and current status of huemul, their general biology and life history, taxonomy, social behavior, and habitat use. It includes many figures and good-quality color photographs. It ends, appropriately, with a section on threats and conservation needs.
As with many rare species, there appear to be a number of factors contributing to the decline of huemul. Unfortunately, direct evidence of the relative significance of each of these factors is still lacking. Hunting was clearly important during the settlement period and is still known to occur, but with better protection is now less serious. Huemul also avoid areas grazed by livestock, even those that offer otherwise suitable habitat. The reasons for this are unclear, although it could be due to their susceptibility to livestock diseases or to avoid harassment from dogs. An additional puzzle is a low but variable recruitment rate. Observations of huemul in late winter often reveal that the majority of adult females have no surviving fawns, in spite of the fact that they usually appear in good condition.
An issue that is now of increasing concern is the expanding population of red deer, which have become established in the wild following escapes from deer farms. Red deer have a similar diet to huemul and are not subject to any control or management. At present, there is very little overlap in range with huemul, but the potential effects of competition, disease transmission, or behavioral interference are not known. Answers to such questions are needed to help guide conservation efforts for huemul. Unfortunately, investigations on such rare and inaccessible animals provide few observations, making it difficult to obtain enough ecological information to guide conservation efforts. Improved methods of monitoring huemul populations are urgently needed to enable managers to determine trends quickly, as are reliable capture methods, for both research and captive breeding.
The book is a useful source of information on the current plight of the huemul and is definitely recommended for those involved with conservation in the region or of huemul in particular. It deserves to be read more widely, for example, by others involved in conservation policy or in research on endangered mammals. Hopefully, this will attract more interest in this little known species and ensure it does not become one of the few deer species to go extinct.