Mountain Bluebird in September

September is the peak of fall migration. Huge numbers of birds move south on cold fronts, mixed flocks form, and summer residents slip away almost unnoticed. Young birds making their first migration appear in places the species rarely visits.

For the Mountain Bluebird specifically, September is a fall month of relative routine, with the species settled into its seasonal pattern across its range. Across the 23 states and provinces where mountain bluebirds occur, what the bird is doing this month depends heavily on latitude — the details below break it down by band.

Southern states

absent

Mid-latitudes

year-round resident

Northern states & Canada

absent

In September, mountain bluebirds are absent in the South, year-round resident across the mid-latitudes, and absent in the northern states and Canada. That north–south split is the defining feature of this month: where you live changes which version of this bird you're looking at.

Mountain bluebirds are not nesting in September. The season runs May–July at mid-latitudes.

That makes September a useful month for nest-box work: cleaning out old nesting material, checking mounts and predator guards, and making repairs while boxes are empty. A box that's ready early gets claimed early.

Mountain Bluebird nest box dimensions and mounting →

• Grasshoppers, beetles and caterpillars

Nests at high elevations in open country; takes nest boxes on fence lines.

Migrants passing through may stop at feeders for a day and never return — September rewards watching closely. Natural seed and fruit crops are abundant, so feeder traffic can be uneven.

Full Mountain Bluebird diet guide → · Best feeder for mountain bluebirds →

Mountain bluebirds are settled and predictable in September, which makes this a good month to learn the bird's routine — same feeders, same perches, same times of day.

If you have a Mountain Bluebird box up, this is the month to make sure it's clean, secure and ready — the box guide below has the exact hole size and mounting height this species needs.

AlaskaAlbertaArizonaBritish ColumbiaCaliforniaColoradoIdahoKansasManitobaMontanaNebraskaNevadaNew MexicoNorth DakotaOklahomaOregonSaskatchewanSouth DakotaTexasUtah