More than 400 different species of birds can be found throughout Colorado, but in recent years, wildlife officials have observed the population of bluebirds decreasing at an alarming rate.

According to the Audubon Society of Greater Denver, there are a couple of reasons why Mountain, Western, and Eastern bluebirds are becoming less common in Colorado. The primary causes of the population dip are habitat loss and increased competition for nesting sites. Bluebirds are second cavity nesters, which means they aren't capable of making their own homes, but rather move into nests that have been previously established by other birds. These social migratory songbirds will also make their homes inside of artificial nest boxes or use natural holes in trees.

Despite the population decline, efforts are also being taken to conserve the three species of bluebirds that live in the Centennial State. This is being carried out through the official Colorado Bluebird Project.

The Colorado Bluebird Project aims to improve the vitality of bluebird populations throughout Colorado and inform and educate the public about the species. The project operates under the guidance of the Audubon Society of Greater Denver.

While exploring Colorado trails or open spaces, you may have passed by one of the components of the Bluebird Project and not even realized it. Artificial nest boxes, like the ones in the photo below, are being installed in various parks and on other properties, such as schoolyards in Colorado. In Castle Rock alone, there are 190 boxes spread out at various parks, schools, open spaces, and trails.

Kelsey Nistel/TSM

These artificial nest boxes perfectly imitate tree cavities where bluebirds make their natural nests. Providing these makeshift nesting sites is an important step to help bring back the bluebird. They are placed in areas that are conducive to the species and their feeding habits, including nearby grassy meadows or on the edge of woodlands. Between April 1 through early August, volunteers monitor and check the activity taking place at the boxes once a week.

Although the holes on the front of the artificial nest boxes are narrow enough to keep predators out, they are also large enough to let other birds in, which is just another benefit of the project. Besides bluebirds, the nests can serve as homes for other species of birds, including swallows and house wrens.

Anyone can install an artificial nest box in their yard or on their property to help sustain the bluebird population in Colorado.

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