Photo: Wikipedia
Male Tree Swallow

By Joyce Moore

When the Calgary Nest-box Monitors gathered this fall at St. Andrew’s Centre to tally up the number of Mountain Bluebirds and Tree Swallows fledged this season they did so with long faces. These are the volunteers who care for the nest-boxes that you see along country roads. They clean them out in the fall, count the number of eggs laid in the spring, the number of nestlings hatched and keep track of the young that have fledged.

The headline from the report stated: ‘Sharp Decline in Our Monitored Species’. It went on to say that long stretches of cold, wet weather this summer played havoc with their activities involving nest-boxes and their inhabitants. Both species declined considerably after reaching highs in the previous two smoky summers.

Mountain Bluebirds numbers were only 73% of last year totalling 5502, compared to 7532 in 2018. Mountain bluebirds may raise two clutches in a season and because of the wet July, the biggest drop was in second broods. For the same reason, Tree Swallows fledged dropped from 14,310 last year to 9849 this year.

Another cause in the decline was the up-tick in house wren numbers. These aggressive little birds that not only use the boxes for nesting, they also go around filling other boxes with sticks so that the swallows and bluebirds can’t use in them either.

At the meeting, each monitor had a chance to tell tales from his own trail and there were sad stories of finding abandoned eggs or dead young in the boxes that spoiled the pleasures of tending to the birds. Not all trail numbers were down and there were good stories too.

Some individuals remarked that they usually are tormented by mosquitos when they are out checking their boxes but not this year. A shortage of this food source can pose a serious problem for these birds that are air insect eaters.

Two different monitors who had boxes on busy roads, one at an intersection near Chain Lakes the other on Highway 22, noted that the birds weren’t nesting in the boxes. So they moved the boxes to quieter roads where the nesting process continued normally. The failure to nest was attributed to the disturbance caused by traffic noise.

The Nest-box Trails stretch approximately from Olds in the north to Stavely in the south mostly west of Highway #2. These trails were checked by 88 individuals some working in teams of two or more, some alone. Each team drove about 125 miles on average to cover the route. The monitors checked their boxes three or more times so the many miles they travelled show their dedication and enthusiasm for the work.

The long-time coordinator for all this activity is St. Andrew’s Don Stiles He had a birthday upcoming and his son, Andrew, remarked that his Dad has spent half his long life with bluebirds and tree swallows.

Andrew himself is involved with children, nest boxes, bluebirds and tree swallows and runs an education program for schools that reaches some 2000 students each year in grades one, two and three this year.

Joyce Moore’s column originally appeared in The Western Wheel on November 13, 2019