Botanical Composition and Diet Quality of the Vicuñas (Vicugna vicugna Mol.) in Highland Range of Parinacota, Chile

Abstract

Understanding the botanical composition of herbivores’ diets and their nutritional quality is an important question in the development of sustainable strategies for the management of natural resources. In Chilean highland vicuña-grazed grasslands, there is little information in this regard and, therefore, this study aimed to determine the year-round profile of the diet’s botanical composition and quality. In highland grasslands, on an area of 21.9 ha, continuously grazed for 3.06 VU/ha/year (18°03′ S, 69°13′ W; 4425 m.o.s.l), twelve feces piles were sampled monthly and were analyzed through microhistology, and the nitrogen concentration [NF, OM basis] was determined. The botanical composition, diversity (J) and selectivity index (Ei) of the main species were estimated. Diets were composed of dry–grassland grasses (37.7%), wet–grassland grasses (36.6%), graminoids (14.3%) and forbs (10.2%). The diet diversity ranged from 0.79 (dry–winter) to 0.87 (wet–summer). The main dominant grassland species obtained negative Ei values. The annual mean value of [NF] was estimated as 1.82%, with a higher value in summer months (2.21%), which coincides with the physiological states of higher nutritional demand. The vicuñas behave like generalist ungulates, having a high degree of selectivity towards grass species, which mostly fulfill a nutritional role in subsistence and a functional role in survival, applying foraging strategies that allow them to obtain a better quality diet during the season of greatest nutritional demand.

Dieta estival del piuquén (Chloephaga melanoptera Eyton, 1838) en praderas hidromórficas de la Cordillera Andina de la Región de Coquimbo, Chile

“…Sin embargo, y a diferencia de lo que ocurre con E. pseudoalbibracteata, su aporte, tanto en los pastizales como en la dieta, fue bajo (< 5%). Estas especies podrían cumplir roles como mejoradoras de la calidad de la dieta, ya que a pesar de estar presentes en una baja proporción en el pastizal, los herbívoros son capaces de seleccionarlas (Castellaro et al, 2020).…”

Paleodiet of Lamini camelids (Mammalia: Artiodactyla) from the Pleistocene of southern Brazil: insights from stable isotope analysis (δ13C, δ18O)

“…Studies with modern guanacos and vicuñas have shown that the diet of these species comprises a wide range of plant resources, especially grass species, depending on the seasonal and spatial availability of primary producers (Puig et al 1996, 1997, 2011; Torres and Puig 2010; Rivals et al 2013; Castellaro et al 2020). Hence, based on their modern diet, it is possible to infer that the results found in the present study reflect the consumption of grasses rather than shrubs or trees.…”

Summer Diet of Horses (Equus ferus caballus Linn.), Guanacos (Lama guanicoe Müller), and European Brown Hares (Lepus europaeus Pallas) in the High Andean Range of the Coquimbo Region, Chile

“…The dominant species of the hydromorphic grassland, Carex gayana and Eleocharis pseudoalbibracteata in the diet of horses, presented negative E i although close to zero, which would be an indication of a DM intake proportional to its abundance in the grassland, fulfilling a nutritional role of maintenance and a functional role of volume in equines [ 25 , 72 ]. The exception to this behavior was D. chrysostachya , a species that tended to be rejected.…”

“…In the leporids, the intake of M. potentilloides could be explained by the fact that these plant species could contain certain essential nutrients in high concentrations, and that when selected, would contribute to a more balanced diet [ 60 ]. In the case of equines and guanacos, the selection of S. crishophylla could contribute to achieving the minimum effective fiber necessary for the health of the digestive tract and the proper functioning of the fermentative process at the pseudo-rumen and colon level, respectively [ 48 , 72 ].…”

“…In the diet of horses, the main grasses of the dryland grassland, Hordeum pubiflorum and Festuca panda , would fulfill a nutritional maintenance role and a functional volume role, because they were consumed in proportion to their abundance [ 25 , 72 ]. However, in guanacos, F. panda was selected, while H. pubiflorum was consumed in proportion to its abundance.…”