If your target species are larger cavity-nesting birds, like American Kestrels, you may have to actively deter starlings from your area. Simply restricting the size of the entrance hole of a nest box should be enough to give the smaller birds access while keep starlings out. There are several styles that seem to deter the sparrows for a while, but ultimately if these birds are desperate, they will eventually use the box.īecause European Starlings are a larger bird, they are less of a problem when it comes to competition with bluebirds and other smaller cavity-nesting species. Unfortunately, a completely sparrow-proof nest box does not exist. We recommend that you take measures to prevent them from breeding in your boxes. For the reasons outlined above, we strongly encourage that you do not allow House Sparrows or European Starlings to breed in your nest boxes. Photo © Mary Fran Deterring House Sparrows and European StarlingsĪs a nest box monitor, your goal is to provide a safe environment for local cavity-nesting species to breed. For more information on the biology of these species, please visit these pages. They outcompete native cavity-nesting birds, and are known to destroy nests and eggs, and kill nestlings and adults while taking over an occupied nest site. Both species nest in structures ranging from gutters and downspouts to thick shrubs and bushes, but readily use nest boxes when available. They are now permanent residents found across the United States and Canada, almost always near areas of human habitation and disturbance (e.g., cities and suburbs) or areas with a reliable food source, such as barns or granaries. House Sparrows and European Starlings were both introduced to North America in the 19th century. Invasive species are currently recognized as one of the main threats to global biodiversity. Invasive exotic species are those introduced species which benefit from their new environment such that they increase their population range significantly over time. Please note that the methods described below are only for controlling House Sparrows (Passer domesticus) and European Starlings (Sturnus vulgaris), which are not protected by the Migratory Bird Treaty Act, and that it is illegal to harm or harass any native species, including their nests and eggs. Flocks tend to break up through the autumn and birds return to their nesting colony sites.Joan Gellatly Managing House Sparrows and European Starlings
Later, rural flocks may move on to grainfields to feed on the ripening grain, often joined by adult birds, once they have finished nesting. These may be areas of wasteland or around garden feeding sites. Newly independent young often gather in large flocks, anywhere there is an abundance of seed, invertebrates and other suitable foods. She can begin laying her next clutch of eggs within days of the previous brood leaving the nest. Post-fledging care is frequently left to the male as the hen prepares for the next brood.
They are unable to feed themselves for about a week after leaving the nest and are cared for by their parents for around a fortnight. The young fledge 14-16 days after hatching. cold weather) and become more important after the chicks leave the nest. Seeds and vegetable matter are also given, particularly during periods when invertebrates are scarce (e.g. The youngsters are fed on a variety of invertebrates, including aphids, caterpillars, beetles and grasshoppers. Chicks are brooded for 6-8 days, but can control their own body temperature only when 10 or 11 days old. The parents share nesting duties equally.
Both sexes incubate, and the chicks hatch after 11-14 days. The female lays two to five eggs at daily intervals and often starts to incubate part way through egg-laying.