Covenant pest

There are Covenant Pests that can be found in Halo 2 on the level "Gravemind". On the three floors of the detention center there are what looks like small insects crawling around the place. No one really knows how and where these little pests came from but some theories are that they are a food source for either lower species of the Covenant or are just pests, similar to Roaches in a city apartment. This is quite unlikely due to the cleanliness seen throughout the rest of High Charity, especially the Sanctum of the Hierarchs. They came from plant life that the Covenant brought from Installation 04 or certain shipments from other planets brought them through the large metal storage crates seen throughout the city. The pest is very small and yellow. It seems to slide on the floor and on the walls, and once anyone approaches one it, slides away. They are able to be shot at, but are unable to be killed.

Other wildlife on High Charity include what appear to be fish in the Hanging Gardens and in the Valley of Tears.