Human hair as a nest-building component for birds? Yes. A reader recently asked that question. Many bird species incorporate animal or human hair in their nests. Some people, perhaps like you, can pull it from the brush (my brush doesn't need cleaning very often). Others go so far as to collect cut hair from the floor of the salon or barber shop to carry home and offer to the birds. A site I found via Google suggested placing the hair in a mesh bag of some sort (onion, potato, oranges). I've seen animal hair in nests of chickadees, for example, but I've never considered human hair. Long strands would be good for binding other nesting materials together.