Alpacas nibble only the tops of grasses and other plants; they do not rip plants out of the ground, resulting in less disturbance of the vegetation and allowing it to grow back.
In contrast to goats and sheep, wich have sharp hooves that damage pasture and soil, alpacas have two toes with toenails on top and a soft pad on the bottom of each foot that minimizes their effect on pasture-land.
The natural habitat of alpacas is about 3.800 metres above sea level. At this altitude, the water supply is natural and the land is generally not suitable for agriculture.
The efficiency of alpacas is especially notable considering that they require much less food intake than most other fibre-producing livestock.