The Indigo Bunting often migrates during the night, using the stars to navigate. This is not an unusual proposal, for many other birds such as the blackcaps or red-barked shrikes were used to test if birds have orientated migratory behavior or Zugunruhe. Research indicates that Indigo Buntings placed in funnel cages outside on cloudless autumn nights or in artificial planetariums made more southern directional choices. When introduced to increasingly overcast nights, many bunting’s abilities to distinctively make southern directional changes decreased, possibly indicating a negative correlation between Zugunruhe and cloud coverage. When in the artificial planetarium scenario and in the presence of a magnetic field similar to Earth’s, birds were unable to orientate themselves in a no-star environment, indicating that past hypotheses supporting that birds use geophysical clues as well may be incorrect.