What strange feature does this desert bird have in common with sea birds?
For most birds, the kidneys are responsible for removing excess salt from the blood. Because some sea birds consume so much salt, part of the job of removing the excess is carried out by special glands in their nose. Roadrunners also have these salt removing glands, which do the job with much less water than the kidneys would use. Since roadrunners are desert birds, every drop of water is important to them, so this is a very useful adaptation.