|Tarascons on high-altitude summer pasture. Image: Vincent Gleyses|
The Tarascon is a middle-sized, horned sheep breed, developed in the 19th century in the Central Pyrenees, France. It is kept for meat. Tarascon sheep are hardy and strong-limbed, adapted to thrive on poor mountain pastures (1200 m above sea level) and seasonal transhumance. Unusually, they can lamb year-round, instead of only in spring. The fleece is white and very curly, with no kemps or guard hairs.
The practice of regularly moving livestock between specific grazing grounds to take advantage of differences in growing season (transhumance) has been practiced by pastoralists worldwide. In mountainous areas, it typically means extensive grazing at higher altitude in summer, and more intensive grazing in lower valleys in winter.
Differences in altitude affect the isotopic composition of graze. Firstly, different mixes of species grow at different altitudes. Secondly, plant isotopic composition is affected by differences in temperature, rainfall, hours of sunshine, and soil quality. The tissues of transhumant livestock will reflect these differences, but seasonal cycles of isotopic change will be obscured.