June 27th, 2011

A few posts ago, I described a “citizen science” program called “Project Nest Box” that  I am participating in with students at the Blair Outdoor and Environmental Education Centre.  We assembled, installed and have been monitoring 6 nest boxes since April.  Our observations are sent to Bird Studies Canada via an on-line data entry system.  I usually check the boxes on Mondays and Fridays to determine the status of the nesting process, and with the help of a hand-held mirror, students can see the nest, eggs, or nestlings in the box.

I’m happy to report that it looks like this brood of tree swallows will be ready to leave the nest any day now.  All 6 eggs hatched, and all nestlings have survived to this point.  Their eyes are open, they are fully feathered, and it’s getting a bit crowded in there!!

Adult birds were bringing food to the young this morning, and will continue to for a short time after fledging.  Tree swallows capture insects on the wing in dazzling, acrobatic flight, so the young must learn first to fly, then to catch their own meals soon after leaving the security of the  box.  In the video below you’ll see Mom arriving with food, and leaving almost immediately with a “fecal sac”.  An excellent link to nestling development: http://www.treeswallowprojects.com/cgrowth.html

I had pretty much given up on the house wren occupying another of the boxes. But this morning – to my surprise – I discovered six eggs in that nest.  Although the male has been singing from a perch atop the box for some time, and a twig nest had been completed, I wasn’t certain that he had been convincing enough to attract a mate as several weeks of (apparent) inactivity had passed.  Ants have also established a fairly large colony among the twigs of the nest, which may prove to be a threat to the young birds.  Wrens often include spider egg sacs in the nest which may in turn deter various nest parasites!!  http://www.allaboutbirds.org/guide/House_Wren/id

This has been an outstanding program at a number of levels – students are excited to see and learn about the birds, and to know that they are contributing to real science.  And the birds have taken advantage of the nesting conditions made available to them, and have been successful in rearing a family.  Many thanks to Clean River Recycling Solutions for their sponsorship of this program.

The barn swallow, and the chimney swift – two birds similar to the tree swallow in their aerial feeding habits – are now on the list of Canadian species-at-risk.  Reduced numbers of insects as a result of pesticide use, and loss of suitable habitat for their unique style of attaching nests to vertical surfaces are the suspected causes.