Why is the Bushtit nest impressive?

It is pendulous… a woven, hanging basket with a hole high up on the side. A passageway leads to the nest chamber at the bottom. The nest, constructed of spider webs, moss, lichen, and plant material can be up to a foot long. Quite big for such a tiny bird.

Bushtits travel in groups, up to 60 birds in size, called “flocks.”