The Alastar are most active between dusk and dawn and bed down during the day. Sound is a key thing for the creatures because they not only use their night vision but also echolocation like a bat to get around. They are always found with others of their kind in groups or flocks anywhere between 20 to 100. During nesting season they take turns watching the hatchings and eggs. The nests themselves are built into small caves at the edge of a deep cliffs. To land they use the claw on their upper wings to grip the rock face and use it and their claws to climb up to the nests.
When or if these creatures are separated from their flock they will let out mournful crys as they search for them. This is however very rare because the groups are very protective of their own. Each group having an Alpha pair of the flock. The creatures are also very elusive despite their size, being roughly around 4 feet. Because of this very few people are able to witness many of these creature's behaviors.
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) instead of Donis will be great. It'll allow me to hoard them. Also, I really like both the coloring and the large size of your creature. Great job!