No, actually those are just hypotheses. What experiment demonstrated that birds are studying the positions of stars while in flight?
https://www.nature.com/articles/nature13290
This is some fascinating research that proves in an elegant way that birds use electomagnetism to orient themselves in the direction they are supposed to migrate.
These birds kept in an urban lab would just bounce around in random directions, confused, but when taken to the countryside, the birds would know which way to orient themselves. They hypothesized that the electromagnetic 'noise' permeating the urban lab was responsible for disrupting the birds' ability to orient themselves in the direction of migration.
If a human was disoriented when you filled his brain with electromagnetic noise and disrupted his brain activity it obviously could be unrelated related to how humans navigate on a higher level. Correlation does not equal causation. There is a lot more to prove there.
Ahhhhhh, Mr. Bishop. Moment please. Your humble expert servant is happy to easily answer your query.
Is your internet search function broken? Simple google search reveal in the 1960's, German ornithologists Franz and Eleanour Saver discovered birds navigate the night sky using stars. They collected data from a series of experiments conducted inside an enclosed planetarium. They determined they used stars to migrate, using a genetically coded map of the stars.
A decade later, Cornell scientist Stephen Emlen, experimented with indigo buntings also inside an enclosed planetarium. He discovered they are programmed to orient to the north star, Polaris. They require a rotating sky to fix on Polaris.
Not just hypotheses afterall.