Which birds can you legally remove in Montana?

Are the birds nesting on my building protected?

Probably. The Migratory Bird Treaty Act protects native migratory birds in the United States, and that protection extends to active nests — a nest with eggs or young in it. Swallows, robins, flycatchers, and the great majority of what nests on a Montana structure fall inside it.

The protection is about the nest being active rather than about the species being rare. A barn swallow is not endangered and is not unusual. Its occupied nest is still not something you can knock down.

Which birds are not protected?

Three, and they happen to be three of the most common pest species: the house sparrow, the European starling, and the rock pigeon — the ordinary city pigeon. All three were introduced to North America from Europe and none of them is native, so none is covered by the Act. Their nests can be removed at any time, active or not.

The U.S. Fish and Wildlife Service maintains the formal list of species the Act does not apply to, which is where that exemption comes from. It is a short list, and if a bird is not on it the safe assumption is that it is protected.

So can I take down a swallow nest under my eave?

Not while it is active. Swallows are native migratory birds and an occupied nest is protected. Once the young have fledged and the nest is genuinely inactive, removal is a different matter — and that is the moment exclusion work should happen, because an empty nest site will be reused next season if nothing changes.

The mistake we see most often is a homeowner knocking mud nests down repeatedly through the summer. Beyond the legal exposure, it does not work: the birds are already committed to the site and simply rebuild. See swallows nesting on a Montana building for what does work.

When is the safe window for exclusion work?

Before the birds arrive, or after the young have fledged and the site is empty. Those are the two windows, and they are the reason bird exclusion is a scheduling problem more than a product problem. Netting, ledge modification, and deterrent hardware all have to go up while nothing is nesting behind them.

In practice that means the work gets planned a season ahead. If you noticed the problem in July, the fix usually happens in autumn or the following early spring, not next week. Booking it while you remember is more useful than trying to solve it in the moment.

Does it change anything if the birds are causing real damage?

It changes what your options are, not whether the law applies. Droppings on a commercial entrance, corrosion on signage, blocked vents, and contaminated stock are all genuine problems, and there are legitimate routes for handling protected species where there is a real conflict — but those routes run through the wildlife agencies, not through a ladder and a broom.

For unprotected species the calculus is simpler, which is why the identification step matters so much. On a commercial building the birds involved are frequently pigeons or starlings, and that means the work can proceed immediately. See bird droppings at a commercial entrance.

Can you prune a tree with a nest in it?

Not while the nest is active, and this is the point where bird law lands squarely on tree work. An occupied nest belonging to a native migratory bird is protected wherever it is, and a tree canopy in May and June is full of them. A crew that starts cutting without looking is taking a risk on the client’s behalf.

In practice it shapes the pruning calendar. Late winter into early spring, during dormancy, is the ideal window for most pruning in western Montana on horticultural grounds anyway, and it also sits before nesting. Summer pruning is where the check matters, and it is why our crews look before they climb.

If a nest turns up mid-job the work stops in that section and resumes once the birds have fledged. Genuine hazard work — a tree that is failing over a house or a power line — is a different conversation and one worth having with us directly rather than deferring. See tree services and tree health and risk assessment.

Are there local rules on top of the federal ones?

There can be. The federal exemption for house sparrows, starlings, and pigeons removes the federal question; it does not automatically settle municipal ordinances, and rules vary between jurisdictions. If the building is inside city limits it is worth a call to confirm before work starts.

We handle that check as part of scoping the job. If you have birds on a structure in Missoula or the Bitterroot Valley and are not sure what you are looking at, send us a photo — identification is usually possible from one clear picture of the nest and the bird, and it determines everything that follows.

More resources