Tree Swallow Nest Box Research
Tree Swallow Nest Box Study
With over 200 tree swallow nest boxes installed in three areas of the province I have different goals/research for each area. Originally, the goal for all three locations was to increase the available nest sites for both tree swallows and mountain bluebirds but has since morphed into a larger program with different goals based upon the different areas. The combined goals for all three areas include:
1) provide safe and secure nest boxes for tree swallows and mountain bluebirds to raise their young
2) test out different nest box designs and sizes of nest boxes to determine if tree swallows have a preference
3) determine if tree swallows have a preference of nesting distance from each other (30, 60, or 90+m)
4) test out house sparrow nest box resistant openings to prevent house sparrows from using nest boxes that are installed for tree swallows
5) confirm if the Judah Hill area has two different populations of tree swallows nesting there
The goal for the nest boxes installed on a ranch near Hussar was to increase the nesting opportunities for tree swallows on ranch land. The ranch has a large portion of native prairie with wetlands throughout and is grazed by cattle. This area has not had a single mountain bluebird nesting there in the six years I have had nest boxes installed. This ranch also has house sparrows over taking the nest boxes further and further away from the farm buildings and corrals well beyond what literature has stated they would use. Some nest boxes they have taken over are approximately 1km from the nearest building or corral. Therefore the original goal has been altered to include:
1) convert the nest box openings to house sparrow resistant openings to determine if they prevent house sparrows from nesting while allowing tree swallows to nest in the boxes
2) provide tree swallows with safe and secure nest boxes to raise their young
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The goal for the nest boxes installed near Red Deer is to provide nest boxes for tree swallows and mountain bluebirds. This area is the only area where I have been able to attract bluebirds and have "twinned" a couple of bird boxes there to accommodate both species. With a large number of trees throughout the area that I have nest boxes installed on a large portion of the nest boxes are used by house wrens.
The goal for the nest boxes installed in the third area, Judah Hill, has also changed to become five goals (listed below). I believe Judah Hill is getting both populations of tree swallows (west coast and central/east coast) nesting there. On one quarter section, with the most tree swallow nest boxes, about half of the nest boxes being used are 7-10 days ahead of the other half of the nest boxes. Because of this nesting date difference and the eBird time lapse map
(http://ebird.org/content/ebird/wp-content/uploads/sites/55/TRES_1s.gif) it appears both the western and eastern populations are nesting here.
On the same quarter section I also have started a study to determine if the tree swallows prefer a specific design or size of nest box, if they will use house sparrow resistant openings and how far apart they prefer to nest from each other. The designs include 3 different designs: 1) rectangular 2) angled roof and 3) the Golondrinas design but I altered the width and height (http://golondrinas.cornell.edu/default.html). There are two different nest box sizes that vary in width but not height 1) boxes with 4x5.5" floors and 2) boxes with 5.5x5.75" floors. Of the 4x5.5" floor rectangular nest boxes I used two different types of wood, spruce and pine to see if one species of wood lasts longer. I had 12 nest boxes previously installed in this area that I have retrofitted with house sparrow resistant nest box openings. I have spaced all of nest boxes out at intervals of ~30m installed on fence posts, numbered them and installed the nest box types in a consistent order. The nest box order is as follows (pictured above);
1) 4x5.5" rectangular pine box (12 boxes total)
2) 5.5x5.75" rectangular pine (12 boxes total)
3) 4x5.5" angled roof pine (12 boxes total)
4) 5.5x5.75" Golondrinas pine (12 boxes total)
5) 4x5.5" rectangular spruce box (16 boxes total)
6) 4x5.5" house sparrow resistant nest box openings retrofitted on pine boxes that were already installed (nest boxes were not moved so are not in the "correct order") (12 boxes total)
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I have seen mountain bluebirds on Judah Hill in prime habitat for nesting, which is where I have also installed nest boxes including one location where I twinned the boxes. However, none of the bluebirds have stayed to breed in the area or at least not yet. Historically they were breeding in this area but it appears that the bluebirds showing up are stopping over on their northward migration to their breeding grounds in the Yukon.
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The goals for the Judah Hill area include:
1) provide safe and secure nest boxes for tree swallows to raise their young and hopefully get bluebirds to start nesting here as well
2) test out different nest box designs and sizes of nest boxes to determine if tree swallows have a preference
3) determine if tree swallows have a preference of nesting distance from each other (30, 60, or 90+m)
4) test out house sparrow nest box resistant openings to determine if tree swallows will use them in areas where house sparrows are not present
5) confirm if the Judah Hill area has two different populations of tree swallows nesting there