Cliff Swallows in California: Why Most Pest Control Companies Won’t Touch Them
If you live in California and have cliff swallows nesting under your eaves or in the corners of your building, you already know how persistent and messy these birds can be. Their mud nests can cause property damage, staining, and even health concerns due to droppings and parasites. Understandably, many homeowners and property managers seek help.
But here’s the reality: most pest control companies won’t touch cliff swallows.
What Are Cliff Swallows?
Cliff swallows are small migratory birds that travel thousands of miles between California and Central or South America each year. They’re best known for their gourd-shaped mud nests, which they build in colonies under overhangs, ledges, and building eaves.
Once one or two swallows show up, it’s only a matter of time before dozens or even hundreds arrive.
Why Control Is Tricky
Protected by Federal Law
Cliff swallows are protected under the Migratory Bird Treaty Act (MBTA), a federal law that makes it illegal to remove or disturb active nests those that contain eggs or baby birds without a special federal permit. Violating this law can result in hefty fines or criminal charges.
This is the primary reason most pest control companies refuse to remove cliff swallows or their nests: it’s illegal during nesting season, which spans from February to September in most parts of California.
What We Do (and when)
Exclusion – The Legal Way to Prevent Nesting
While removal of active nests is off-limits, exclusion is perfectly legal outside of nesting season, usually in the fall and winter. This involves:
Installing physical barriers (like netting or bird spikes)
Smoothing surfaces to prevent mud adhesion
Exclusion is not a guarantee. These birds can be stubborn! They flew thousands of miles to get to their nesting ground and they will try their best to reach it. The goal is to make the area unattractive or inaccessible before the birds return in spring.
Sanitation – Birds by nature are nasty animals from bird mites to diseases
Outside of nesting season removal of their nests along with area sanitation is recommended as the bird mites they brought with them will look for other food sources namely you and your pets.
· Removal of nests and droppings with pressure washer.
· Area scrubbed with virucide to kill all vectors and mites.
What We and You DO NOT DO
Never knock down active nests.
Do not harass, trap, or kill the birds.
Avoid using repellents or chemicals near nesting sites. Not only are they ineffective, but they can also be illegal and harmful to other wildlife.
The key to controlling cliff swallows in California is timing. Once they’ve arrived and started nesting, your options become extremely limited. But if you act during the off-season, you can prevent a yearly mess and avoid any legal trouble.
If you’re dealing with cliff swallows, consult a bird exclusion and sanitation professional like X Pest Defense, Inc. in the fall or winter. A good prevention plan now can save you months of noise, droppings, and headaches later.
