The Arks of the Fathers.
The interior of the ships recreates the environment of the destroyed Hesht homeworld: mostly savannah with dry forests. In addition to the Heshatun themselves, the Arks carry an entire ecology including:
The Arks are fashioned from asteroids hollowed out to provide an interior surface area of several tens of square kilometers, with the rocky outer surface retained to provide protection from interstellar debris. Pulsed thermonuclear propulsion and mass drivers are used to move the habitats up to sub-light velocity.
Troublesome youngsters are exiled from the Ark ships.