Stable carbon isotope measurements on hair from wild animals from altiplanic environments of Jujuy, Argentina

The use of stable carbon isotopes as dietary tracers is an application that is widening its scope within the fields of ecology and paleoecology. Although hair is potentially one of the most favorable animal tissues for isotopic measurement for dietary studies, this tissue is rarely included in research works. This may be due to the fact that many aspects related to hair tissue are not fully understood, especially in the case of wild animals whose diets consist of plants with contrasting C-13/C-12 ratios, their abundance depending on seasonality. The present isotopic study of hair from animals inhabiting the Andes in northwestern Argentina, at heights ranging from 3500 to about 5000 in above sea level (asl) shows that 1) delta(13)C values measured on hair from herbivores with a mixed and isotopically contrasting diet, and from their carnivorous predators, differ in their respective trophic levels, 2) in primary consumers, different types of hair from the same individual have different delta(13)C values, whereas hair values are homogeneous in carnivores, and 3) some types of hair from rodents, such as whiskers, show delta(13)C values similar to those of less metabolically active tissues such as bone collagen.