Is it legal to remove a bird nest in New Hampshire?

Not if it's active — meaning it has eggs or young — and belongs to a protected species, which is nearly every native bird under the federal Migratory Bird Treaty Act. Only the house sparrow, European starling, and rock pigeon are exempt and can have nests removed at any time (USFWS). For any other species, wait until the nest is confirmed inactive before touching it.

When can I legally exclude bats in NH?

Mid-August through mid-May, per NH Fish and Game. That window avoids the maternity season, roughly June through August, when excluding adult bats through a one-way door would trap flightless pups inside where they'd die of dehydration or starvation. Exclusion done properly inside that legal window uses one-way doors that let bats leave to feed at night but not return, followed by permanently sealing the opening once every bat has confirmed left.

Do plastic owls or ultrasonic bird repellers work?

Only briefly, if at all. Birds and bats habituate quickly to visual scare devices and ultrasonic units once they realize nothing is actually happening, so any deterrent effect fades within days to weeks and the roost activity typically resumes. Physical exclusion — netting, spikes, sealed entry points, and one-way doors used strictly within the legal window — is the only durable, lawful fix for persistent nuisance birds and bats.

Is bat guano dangerous to clean up?

Large accumulations can harbor Histoplasma spores, a fungus that causes a respiratory illness when the spores are inhaled, per NH Fish and Game. Clean guano using wet methods only — never dry-sweep it, which aerosolizes the spores into the air you're breathing — and wear a proper fitted respirator, not just a basic dust mask, for any accumulation of meaningful size.

What should I do if I find a bat indoors?

Avoid direct contact, and don't simply catch and release it if there's any chance of skin contact or an unnoticed bite — the CDC recommends reporting potential bat exposure, since bat-associated cases account for most recent US human rabies deaths and bites can go unnoticed, especially during sleep. If contact is possible, contact NH DHHS and a healthcare provider promptly rather than handling the situation entirely yourself.

How do I stop pigeons from roosting on my building?

Install spikes or netting on ledges, sills, and other flat roosting surfaces, and seal any roost sites you find once they're confirmed empty. Pigeons are one of only three unprotected US bird species, so this exclusion work can legally be done at any time of year without a maternity-season or nesting-timing concern — unlike protected native species or bats, where timing is everything.

Are bats actually beneficial to have around?

Yes — bats are major consumers of night-flying insects, including mosquitoes, and New Hampshire's populations are already under significant stress from white-nose syndrome, a disease that has devastated regional colonies. That's a large part of why the law favors humane exclusion at the right time of year over any form of extermination, and why offering a nearby bat house as an alternative roost is commonly recommended alongside exclusion.

Can I use poison on nuisance birds or bats?

No — poisoning birds or bats is not a legal or appropriate control method under New Hampshire or federal law, regardless of how much of a nuisance they've become. Exclusion, deterrents, and roost-sealing are the lawful route for both protected and unprotected species alike; a licensed wildlife professional is the right call for anything beyond simple ledge-level deterrents on unprotected birds.

Is natural bird and bat exclusion safe for pets?

Yes — netting, spikes, and sealing entry points don't involve any chemicals that pose a direct risk to pets. The main hazard from this method falls on the person doing guano cleanup, given the Histoplasma spore risk, rather than on pets specifically, though it's still sensible to keep pets away from an active roost or a guano-affected area until it's been properly wet-cleaned.

Do I need a professional for bird or bat exclusion?

For bats and any protected native bird species, yes in most cases — the legal timing rules and the height and access involved, think rooflines, soffits, and chimneys, make this professional territory rather than a weekend project. For unprotected birds like pigeons on ground-level ledges, a homeowner can often install spikes or netting themselves without professional help required.

Natural & OrganicUrban Pest Birds & Bats

Natural Bird & Bat Control in NH: The Legal Limits That Matter

TL;DR

Physical exclusion rates MODERATE and is genuinely effective — but the bigger issue here is legal, not technical. Bats and nearly all native birds are legally protected in New Hampshire; only house sparrows, European starlings, and rock pigeons can be excluded freely. Never exclude bats during maternity season or remove an active protected nest.

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Only three unprotected US birds
House sparrow, European starling, and rock pigeon
USFWS — every other native species is protected under the Migratory Bird Treaty Act
MBTA nest protection
Illegal to remove an active nest (with eggs or young) of a protected species
USFWS — violations carry heavy penalties
NH bat exclusion window
Mid-August through mid-May, outside the maternity season
NH Fish and Game — excluding bats during maternity season traps flightless pups
Bat reproduction rate
Most bat species have just one pup per year
NH Fish and Game — populations recover slowly, especially post-white-nose syndrome

The honest verdict

Does this actually work?

MODERATE for exclusion (netting, spikes, sealing, one-way bat doors) when done in the legal window — durable and humane; LOW for visual/ultrasonic scare devices, which animals habituate to quickly; the binding constraint on this method is legal timing and species ID, not technical effectiveness.

Works — Moderate

Evidence: The Migratory Bird Treaty Act protects roughly 1,100 native bird species, their nests, and eggs, with only three US species exempt (USFWS). NH Fish and Game sets the bat-exclusion window at mid-August through mid-May specifically to protect flightless pups during maternity season.

Works when

Exclusion is done within the legal window for the species involved
One-way bat doors are used only after pups have fledged (post-mid-August)
Deterrents (spikes, netting) are installed on ledges for unprotected species like pigeons
The species is correctly identified before any action is taken

Fails when

Bats are excluded during maternity season, trapping flightless pups inside
An active nest of a protected species is disturbed or removed
Visual scare devices (plastic owls, reflective tape) are relied on long-term
The species isn't correctly identified before acting

At a glance

Before you exclude anything — here's the legal line that governs natural bird and bat control

How it works

Pro-only

Natural bird and bat control works by physical exclusion and deterrence rather than any chemical or lethal method: seal or screen entry points, install one-way doors so bats can leave but not return, and use netting or spikes on ledges to prevent roosting. Because most of these species are legally protected, the method's effectiveness always has to be read alongside a legal question — is this species and this timing allowed — which isn't true of any other pest group on this hub.

Vital stats

Time: Seasonal — bat exclusion is a single legal-window project; bird deterrents are installed once and maintained
Best for: Unprotected nuisance birds (house sparrow, European starling, rock pigeon) year-round; bats and protected native birds only within their legal exclusion windows.
Cost: Moderate to high — heights, legal compliance, and specialized materials (netting, one-way doors) typically require professional work

Netting, spikes, and one-way exclusion doors are genuinely effective natural tools against nuisance birds and bats, and they work without a single chemical. But the question this page has to answer first isn't "does exclusion work" — it's "is it legal to use it on this species, right now." That's an unusual framing for a pest-control page, but it's the honest one: get the timing or the species wrong and a homeowner can violate federal and New Hampshire wildlife law without meaning to.

Here's the short version. Only three US bird species — house sparrow, European starling, and rock pigeon — are legally unprotected and can be excluded or have nests removed at any time. Every other native bird, and every bat species, is protected, and bats specifically can only be excluded during a defined window (mid-August through mid-May in New Hampshire) that avoids trapping flightless pups during maternity season. This page covers what's genuinely effective and, just as importantly, when it's legal to use it.

Step by step

How to do it

Identify the species
Determine whether you're dealing with a protected native bird, an unprotected species (house sparrow, European starling, rock pigeon), or a bat — this single step determines everything that's legally allowed next.
Caution: Misidentifying a protected species before acting is the most common way homeowners run into legal trouble.
For bats: confirm you're in the legal window
Only proceed with exclusion mid-August through mid-May, after pups have fledged and before the next maternity season begins.
Caution: Excluding bats outside this window can trap flightless pups inside, where they die and cause odor and secondary pest problems.
Install one-way exclusion doors for bats
Fit one-way doors over active bat entry points so bats can leave to feed but can't re-enter, then seal the opening permanently once you've confirmed they're out.
Tip: Give it several nights before sealing, to be confident every bat has actually left.
For unprotected birds: remove and exclude at any time
House sparrows, European starlings, and rock pigeons can have nests removed and roost sites excluded at any time of year — no legal timing constraint applies.
Tip: This is the one bird scenario where a homeowner can act immediately without a waiting period.
For protected birds: wait for the nest to go inactive
Leave an active nest of a protected species alone until the eggs have hatched and fledged and the nest is confirmed empty, then use deterrents to discourage a repeat nesting.
Caution: Removing eggs or young of a protected species is a federal violation under the MBTA.
Clean guano and droppings safely
Wet down guano before cleanup — never dry-sweep it — and wear a proper respirator for any sizable accumulation, due to Histoplasma spore risk.
Caution: Dry-sweeping guano can aerosolize spores and cause respiratory illness.
Install lasting exclusion hardware
Once the space is legally clear, install netting, slope covers, spikes, or vent screens to prevent the same roost or nest site from being reused.
Tip: A bat house at least 25 inches tall, per Bat Conservation International guidance, gives displaced bats an alternative roost nearby.

What you need

Tools & materials

One-way bat excluder / netting
Humane bat eviction within the legal exclusion window
Only for use mid-August through mid-May in NH
Bird netting or spikes
Deterrent for ledges and roost sites
Legal for unprotected species at any time; for protected species only after nest inactivity
Respirator and wet-clean kit
Safe guano and droppings cleanup
Histoplasma spore risk — never dry-sweep
Sealant and hardware cloth
Permanently seal roosts and nest sites after wildlife has vacated
Apply only once the space is confirmed empty and legally clear

Products & actives

What to use — the label is the law

Product classes only — never a dosage. Always read and follow the product label.

Bird spikes

Active class: Mechanical deterrent

Ledge and sill roost prevention

Install per manufacturer spacing guidance

Exclusion netting

Active class: Mechanical barrier

Lawful deterrence over larger roosting or nesting areas

Confirm the area is legally clear of active nests/roosts before installation

Bat house

Active class: Alternative roost structure (not a repellent)

Offering displaced bats a nearby roost after legal exclusion

At least 25 inches tall per Bat Conservation International guidance

Stay safe

Safety first

General
High risk
Bat guano accumulations can harbor Histoplasma spores — wet-clean only, never dry-sweep, and wear a proper respirator for sizable cleanups (NH Fish and Game).
General
Severe
Any direct contact with a bat, including a possible bite while sleeping, should be reported and evaluated — most recent US human rabies deaths are bat-associated (CDC).
General
High risk
Never trap flightless bat pups inside by excluding outside the legal window (mid-August–mid-May in NH).
General
Caution
Roof, chimney, and soffit-level exclusion work involves fall-height risk — this is professional territory in most cases.

Avoid these

Common mistakes

Why this method fails in practice.

Excluding bats during summer maternity season, trapping flightless pups inside
Removing or disturbing an active nest of a protected bird species
Dry-sweeping guano instead of wet-cleaning it, risking Histoplasma exposure
Assuming all birds are fair game for removal when only three US species are unprotected
Relying on plastic owls or ultrasonic devices for lasting control

New Hampshire context

Natural bird & bat control in New Hampshire

NH Fish and Game sets the bat-exclusion window at mid-August through mid-May, specifically to avoid maternity season when flightless pups can't follow their mother out through a one-way door. Two of New Hampshire's building-roosting bat species — the little brown bat and the big brown bat — are of special concern following white-nose syndrome, which has devastated regional bat populations, so exclusion timing matters even more than the general rule suggests. State and federal law (the Migratory Bird Treaty Act) protect nearly all native birds; only house sparrows, European starlings, and rock pigeons are exempt.

Peak season

Bat maternity season (roughly June–August) is off-limits for exclusion; the legal window is mid-August–mid-May

NH Fish and Game and the federal Migratory Bird Treaty Act (enforced via USFWS) govern nest and bat-roost removal — confirm species and season before excluding anything.

NH Fish and Game's homeowner bat guidance is the citable state authority on legal exclusion timing and humane bat-house alternatives.

This method targets

Pests this applies to

When to call a pro

Bird Control / Wildlife with Anchor

Exclusion and deterrents are genuinely effective, but bat colonies, protected-species situations, guano cleanup, and any roof or height work call for a licensed professional who can navigate the legal timing correctly and work safely at height. Anchor coordinates legal, humane exclusion for bird and bat issues across the region.

Call us when…

A bat colony is roosting in the structure
The species involved is a protected native bird or a bat
Guano cleanup is needed at any meaningful scale
The work requires roof, chimney, or high soffit access
You're not certain of the species or the current legal window

Bird Control / Wildlife

free inspection; same-day service across southern and central New Hampshire.

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Keep them out

Seal potential roost and nest entry points before maternity/nesting season begins
Install ledge deterrents (spikes, netting) on unprotected-species roost sites proactively
Inspect soffits, vents, and chimney caps annually for new gaps

Common questions

Frequently asked

Sources & further reading(4)

[1]
US Fish & Wildlife Service — Understanding Bird Nests and the Law
MBTA nest protection, the three unprotected US bird species
govverified 2026-07-13
[2]
NH Fish and Game — Homeowners and Bats
NH bat exclusion window, maternity-season limits, Histoplasma guano risk, one-pup reproduction rate
govverified 2026-07-13
[3]
PCT Online — When Is the Right Time for Bat Exclusion?
Industry-standard bat exclusion timing and one-way door practice
industryverified 2026-07-13
[4]
CDC — Rabies Prevention
Bat-associated human rabies risk, guidance on reporting potential exposure
govverified 2026-07-13

Written & reviewed by

Verified

Daniel Brady

NH-Licensed Pesticide Applicator · License #782664 (NHDAMF, RSA 430)

Daniel Brady is the New Hampshire–licensed applicator behind Anchor Pest Services, a family-owned pest control company serving the Manchester area since 2017.

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Anchor Pest Services

When urban pest birds & bats won't quit, we will.

Same-day service across Southern New Hampshire. NH-licensed #782664. Family-owned since 2017. We diagnose the pest, then treat it the right way — with a satisfaction guarantee.

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Keep Exploring

Natural Bird & Bat Control in NH: The Legal Limits That Matter

Works when

Fails when

Before you exclude anything — here's the legal line that governs natural bird and bat control

How it works

How to do it

Identify the species

For bats: confirm you're in the legal window

Install one-way exclusion doors for bats

For unprotected birds: remove and exclude at any time

For protected birds: wait for the nest to go inactive

Clean guano and droppings safely

Install lasting exclusion hardware

Tools & materials

One-way bat excluder / netting

Bird netting or spikes

Respirator and wet-clean kit

Sealant and hardware cloth