Can spawn during the Researchers Under Fire event, during the "Neutralizing the Contaminant" and "Hostile Investigators" phases. You'll have to be quick and tame it before others doing the event grab threat.
Circles a dim cavern to the south of Chittering Den and north of Taelloch.
Level scaling: Most NPCs will scale with the Hunter's level, within the constraints of their level range. Hunters can tame regular NPCs up to 2 levels higher than them, but can only tame elite NPCs of the hunter's level or below.