The unique fleece we have discussed yesterday is perfectly adapted to survive in the harsh conditions of the Atacama desert.

However, this insulating fleece can also be a challenge in hot weather. Alpacas have a specific “thermal window” – their belly, armpits, and groin areas – where they can shed excess heat. When it gets too hot (with internal temperatures reaching up to 40°C), they show clear signs of distress: open-mouthed breathing, nasal flaring, drooling, and reduced activity. Dark-colored alpacas are particularly susceptible to heat stress, as are pregnant females, young crias (baby alpacas), and sick or elderly animals. Interestingly, until about a month after birth, crias haven’t yet developed their temperature regulation capability, making them especially vulnerable to temperature extremes.

Fortunately, there are several ways to help alpacas stay cool! The most important is providing adequate shade – either through trees or structures with high ceilings for good air circulation. Shearing before hot weather arrives is crucial, and during heat waves, their legs and bellies can be sprayed with cool water. Some farms create cooling stations by watering down concrete areas where alpacas can rest, or even set up shallow pools in shaded areas. Good ventilation is key, especially with fans directed near the floor to cool their thermal windows. Fresh, cool water must always be available, and some farmers offer additional water with electrolytes during particularly hot periods. These measures are especially important for vulnerable individuals like pregnant females and young crias.

Here is a short video of how to keep an alpaca cool on hot days:

Furthermore, to keep the internal organs cool, they have an arterial network called the carotid rete – a special network of blood vessels near their brain. This arterial meshwork acts like a natural air conditioner, allowing them to cool their brain blood through heat exchange with venous blood that has been cooled by their nasal passages. This specialized system helps them handle the extreme temperatures and low oxygen conditions they encounter in their high-altitude habitats.