Abstract

Methods to monitor and manage populations of reindeer (Rangifer tarandus) and caribou are often impractical, costly, and can be harmful to the animals. Non-invasive techniques that produce high quality and accurate results are better alternatives. We collected blood and faecal samples during 2008 - 2010 from two herds of Fenno-Scandian reindeer to explore the potential of using faecal samples to determine the age class (calf, yearling and adult), the sex, as well as the reproductive status of individuals. This was done using two main techniques: faecal progesterone metabolite concentrations (specifically faecal pregnane) and faecal pellet morphometrics. Faecal pregnane was highly correlated with plasma progesterone and therefore, in theory could be a substitute for traditional hormone procedures. We were not successful in using faecal pregnane for sexing or aging individual reindeer. Using plasma progesterone and faecal pregnane, we were able to determine a pregnancy cut-off value for all of the study reindeer, and were therefore able to clearly differentiate pregnant from non-pregnant females. Using a combination of pellet dimensions including maximum length, width, and depth, we were able to differentiate with high accuracy, three age classes of reindeer (calf, yearling, and adult). A combination of faecal sampling using pregnane and pellet size, with the addition of current faecal DNA techniques, may allow the collection of important population data essential for monitoring and management of wild and elusive species such as wild reindeer and woodland caribou.