Still, you should check with your local and State governments for what is legal where you live. The sparrows – brown-grey birds – are indigenous to Europe, Asia and Africa. House sparrows strongly prefer to nest near buildings; bluebirds prefer to nest farther from buildings. I think that what you are seeing are adult martins who are there to nest. Today, there are an estimated 150 million house sparrows in North America alone, and the species is the one of the most abundant songbirds in the world. Predators include: Hawks, snakes, raccoons, European Starlings, House Sparrows, Owls, and cats. If you have dial-up, sorry, but you might want to find a high speed connection somewhere. Place nest boxes away from human activity and buildings (about 300 feet). Sparrows: English House Sparrow (Passer domesticus) Trapping and eliminating European Starlings and House Sparrows is a must for the Martins to survive. Let me state that House Sparrows are not a federally protected species in the U.S. When it comes to House sparrows, these birds are found throughout North America, in Australia, parts of eastern and southern Africa and South America. So, sparrows can get a jump on claiming nest boxes early in the season. Sparrows attack House Martin nest. Using it's strong beak, a sparrow will even kill an adult martin unable to escape its house. It is a cavity nester and poses many problems for the martins when it attempts to build it's nest in the compartments of martin houses. House Sparrows compete with many of our native bird species for nesting sites. You can find House Sparrows most places where there are houses (or other buildings), and few places where there aren’t. Where native bird species are likely to nest, every effort should be taken to control the House Sparrows attempt to nest. A colony size of less than 10 nests is typical, but there are records of colonies with thousands of nests. By filling in the nooks and crannies of lofts, sparrows (pictured) and house martins are among the British garden bird species that are struggling to find somewhere to nest. What a shame that these folks allow this to happen. They’re quarrelsome, noisy, and when they’re on the ground, they move in vigorous hops that remind me of popcorn popping out of a pan. I think that what you are seeing are adult martins who are there to nest. The common house martin tends to breed colonially, and nests may be built in contact with each other. Eurasian House Sparrows are a non-native bird species that was introduced to the US in the 1800's. Still, you should check with your local and State governments for what is legal where you live. They have been known to sneak into the nests of purple martins and destroy their eggs or kill the young. The nests are possibly already done, and they are now close to egg laying time. There are many species of sparrows: Spanish sparrow, Italian sparrow, dessert sparrow, Kenya sparrow etc. When it was realized that house sparrows do not regularly eat insects outside the nesting season, the birds’ range had already spread tremendously. The Martins are indeed in danger. We loved having some House Martins build a nest above our bedroom window, but when it was attacked we didn’t know what to do.