Thestrals are skittish creatures by nature. Wild Thestrals are especially prone to be spooked easily. The withdrawn nature of the Thestral makes it difficult to properly study their normal behaviors. However, after spending months out in the field with a herd of wild Thestral, I finally got a glimpse into the day-to-day mannerisms of these creatures.

When nervous, Thestrals let out a high-pitched squeak and keep their distance. They may pace around or paw at the ground with their hooves. These are warning signs that the Thestral is uncomfortable and you should move away. An attack in imminent when a Thestral begins making threatening gestures, such as spreading their wings intimidatingly or letting out ear-piercing shrieks.

A relaxed Thestral will make a low humming sound. They will eat openly and lay down, which are both acts of trust and signs that the animal is relaxed around you. Relaxed Thestrals are very gentle and quiet.

Thestrals show affection by nuzzling, making soft chuffing sounds, and sharing food. Most affectionate behavior is seen between a mother Thestral and her baby, although siblings, mates, and Thestrals of other relation will also show affection to one another. 

Thestral herds have a very lenient hierarchy, usually ensuring young offspring and mothers eat first. The males of the herd will not eat until the others have gotten their fill. The dominant males of the herd will survey their territory for prey opportunities and intruders. This hierarchy serves to prevent outright chaos in a herd.

Male Thestrals do battle to establish dominance of a herd. The battles are usually quick and harmless, though fatal incidents have occurred before. The males will raise on their hind legs and "fight" each other with their front hooves. Wing size also plays a significant role in the dominance rivalry. A defeated male is not banished from the herd, but instead lives in the lower ranks of the hierarchy.

An aggravated or startled Thestral will charge at you. Whether the charge will be a bluff or not greatly depends on the circumstances. A healthy Thestral weighs roughly 110 lbs and can run at speeds up to 50 mph, so a charge from a Thestral can be quite deadly. 

Mother Thestrals are incredibly protective and caring when it comes to their offspring. A baby Thestral is rarely ever seen too far from the herd. Mother Thestrals are known to be the most aggressive of all Thestrals, especially when her baby is newborn or very young. Approaching a mother Thestral or her baby that is not properly tamed is incredibly dangerous.

The hierarchy of a Thestral herd is determined by the battling mentioned previously. However, the herds work cooperatively to achieve their goals. For example, two Thestrals that don't normally get along will work together to catch prey. The teamwork of these creatures is admirable.