Mountain bluebirds are cavity nesters and can become very partial to a nest box, especially if they have successfully raised a clutch. They may even re-use the same nest, though not always. Providing nest boxes is a great way to observe these beautiful birds. Mountain bluebirds will not abandon a nest if human activity is detected close by or at the nest. Because of this, mountain bluebirds can be easily banded while they are still in the nest.