Real Estate Market Heating Up (For Birds)
March 10, 2012
By Steve Grinley

     Despite the fluctuating temperatures, bluebirds are already scouting for nest boxes. A few tree swallows have already been spotted in the area and they, too, will soon be searching for residences.

     It is, therefore, time again to provide my refresher on attracting bluebirds, swallows, and other cavity nesting birds:

     Houses, mealworms and water will help to attract bluebirds and other cavity nesting species as Spring approaches. Now is the time to put up a house or clean out existing ones, as bluebirds will start nesting by late March or early April. Bluebirds have two and sometimes three broods in a season, so if they don’t move in right away, you might still attract them later in May or June.

     For the best chance to attract bluebirds you’ll want a nesting box designed for them. Though there are many different styles, most have a 11/2-inch opening that is about six or seven inches above a four-inch square floor. Some have predator guards over the hole to help deter squirrels, raccoons and large birds. Metal plates around the hole help prevent squirrels from chewing and enlarging the hole. Other popular styles include the Peterson box, which is wedge-shaped with a sloping, overhanging roof that helps deter predators, and the Kentucky style, with a long entrance slot at the top, said to deter house sparrows. A box with an open hole in the top also discourages sparrows, though bluebirds don’t mind get wet occasionally. A house made of PVC is also thought to discourage sparrows.

     Bluebirds like an open area for feeding, so placement of bluebird houses should be in or near grassy areas. It is best to place the house on a separate pole away from the tree line, preferably with a baffle on the pole. Further distance from trees may be necessary if house wrens are present. Direct placement onto a fence post or tree can also be successful, but more difficult to discourage predators.

     The house should be placed between four and seven feet high, facing away from foul weather winds. Like many birds, bluebirds are territorial. That is, they will not allow another pair of bluebirds to nest too close. If you are putting up multiple houses, they should be spaced about 200-300 feet apart. Bluebirds hunt crawling insects like hawks. They will perch on a stick and wait for an insect to show itself. A tall stick in the ground near the house can be a favorite perch for bluebirds while they forage for food or guard the house.

     Tree swallows often compete for the same house as bluebirds.

     Swallows are also beautiful birds. They eat flying insects, so they are beneficial as well. For that reason, many people place pairs of houses within 10-25 feet of each other to allow bluebirds and tree swallows to nest side by side. This way, both species’ presence helps control both crawling and flying insects.

     These two species also help protect each other from the aggressive house sparrow, their No. 1 competitor. House sparrows often take over bluebird nesting boxes and will even kill adult bluebirds or swallows in the process. Because house sparrows are so aggressive, bluebird houses should be placed as far away from buildings as possible and they should be monitored on a regular basis, especially early in the nesting cycle. If sparrows are present, their nesting material should be removed. If sparrows become a real problem, trapping the sparrows may be necessary.

     If you want to attract bluebirds with food, or help them during the nesting process, you can put out mealworms in a feeder near the nesting box. This will minimize the time the male spends away from the nesting box, where he can protect his mate from intruders. The female does most of the incubating and only leaves the nest periodically to feed. Thus, having mealworms nearby will help shorten her absence from the nest and further increase their chances for a successful brood.

     Another key to attracting and keeping bluebirds is to provide water. A heated birdbath may attract them through the winter, but water availability is also important during the warmer months. Adding some motion to the water in the bath may also help attract more birds.

     Boxes should be cleaned after bluebird fledglings leave the nest as the adults may use the same house for another brood. Houses should also be cleaned after every nesting season and checked again just before spring. Once established, bluebirds, swallows and other cavity nesting birds will return to the same area every year and more boxes can be added for returning offspring.

Steve Grinley
Bird Watcher’s Supply & Gift
Route 1 Traffic Circle
194 Route 1
Newburyport, MA 01950
BirdWSG@Comcast.net 
978-462-0775 
www.birdwatcherssupplyandgift.com 
Celebrating 24 years of service to the birding community! 
Like us on Facebook! www.facebook.com/birdwatcherssupply