All songbirds are protected in the US, and all migratory species are protected one way or another. Swallows are migratory. Don't disturb them.

If they were English/house sparrows or starlings--they would not be protected (because they would be non-native species). Any swallow you see in Texas is native to the US, by the way.

You can try putting up a nest box for them next year. Duck on Wheels is correct, think of them as being your own private pest exterminators. Instead of giving them money, you wash your deck.

East Hill