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We compared injuries resulting from two different capture methods, i.e. trailing hounds and foot snares, for pumas Puma concolor in a mixed landscape with open grasslands and limited 'retreat' habitat in southern Chilean Patagonia. Injury scores were not significantly different for the two methods, although the small sample size for captures made with snares likely influenced our findings. Based on a potential range of 0-400, the mean injury score for pumas caught using hounds was 56.3 6 132.9 (SD). The mean puma injury score for five animals caught in snares was 3.8 6 1.1. Pumas were injured and/or killed in 86% of captures using trailing hounds. The number of hounds used in a capture attempt did not predict the likelihood of successfully catching a puma (P=0.35), whereas there was a strong relationship between the number of dogs and the likelihood of a fight with the puma (P<0.0001). The odds ratio calculation predicted a 14.7%increase in the likelihood of a fight between puma and hounds with the addition of each dog to the chase. Our results highlight the potential risks associated with trailing hounds in open landscapes. We suggest guidelines for the use of hounds in predominantly open landscapes, and that alternative capture methods such as foot snares should be considered as a potentially safer alternative. Lastly, we make recommendations for the development of injury assessment systems more relevant to catch-and-release research. [ABSTRACT FROM AUTHOR]

Studies the early mortality of newborn guanacos by birth mass and hematological parameters. Methodology used; Percentage of newborn guanacos that died within 10 days of life; Results of the study.

Summary 1. The Chilean National Forestry and Park Service is striving to implement a guanaco management programme of sustained-yield use. To achieve this, the rate, variation and causes of juvenile guanaco mortality must be understood thoroughly. Therefore, we monitored the survival of 409 radio-collared juvenile guanacos in Torres del Paine National Park, Chile, from 1991 to 1996. 2. The Kaplan–Meier product limit estimator of survival for staggered entry was calculated, and survival rates between juvenile males and females and among years were compared using the lifetest procedure in SAS. The Cox proportional hazards model was used to relate mortality rate to explanatory variables such as juvenile sex, birth weight, adult female aggression towards researchers during the capture and tagging of newborns, population density, and mean monthly winter snowfall. 3. Mean juvenile survival rate (ŝ) was 0·38, but varied between 0·31 and 0·55. Survival rates between the sexes were not significantly different, although male survival was lower than that of females. Mortality rate was highest during the first 14 days after birth. Most deaths occurred between birth and 7 months of age. 4. The risk of mortality increased by almost 6% with every 1 cm increase in winter snowfall, whereas the risk of mortality decreased by almost 24% as adult female aggression increased towards researchers. 5. Current management objectives are aimed at the implementation of a rational harvest of guanacos on the Chilean side of the island of Tierra del Fuego. Our results provide improved and updated estimates of juvenile guanaco survival and will aid in the modelling of harvest rates of guanacos in southern Chile. Future proposed harvests from wild populations in southern Chile need to consider the rate and variation of this critical life-history parameter. [ABSTRACT FROM AUTHOR]