The Bluebird of Happiness might be winging its way to your home next spring and what a sad experience it would be if they could not find a suitable nesting site in which to raise a nest full of happiness.
Last year, during the first annual Metchosin BioBlitz on April 30, a pair of western bluebirds were spotted in the highlands of North Metchosin, after a twenty-seven year absence. As the female had food in her beak, it is hoped that these were a breeding pair. Building on that sighting, GOERT (Garry Oak Ecosystem Recovery Team) has initiated a Bluebird Recovery program in Metchosin.
Western bluebirds, which were once common on southern Vancouver Island and nearby areas of Washington and Oregon, are thought to have suffered catastrophic declines from a combination of factors: loss of Garry oak habitat (over 95% gone), removal of standing dead trees (which supply cavities for nesting), reduction of insect prey from pesticide use, and competition for nest holes from exotic and aggressive birds, particularly starlings and English house sparrows. Changes in agricultural practices are thought to be another factor, with mechanization - ploughing and harvesting can be done right to the fence line, thereby removing the hedgerows that are critically important for berries and as habitat for their insect food source.
In the last few years there has been a successful reintroduction program in the San Juan Islands and it is possible that the birds seen and photographed last year were a pair from that program.
Western bluebirds are members of the thrush family. They are insectivores, usually hunting for grubs, cutworms, grasshoppers and other insects from their perch in the branches, swooping down to capture their prey on the ground, where they will also search for earthworms and ants. They are not so proud that they wouldn’t accept any insect that comes within reach though. They will sometimes hold their prey in their beaks and beat them against the ground, a crude but effective tenderizing process? In the winter, as their insect prey hibernates, they turn to fruits and berries.
In our area they have historically been found in sparsely forested ridges as well as open plant communities; grassy and herbaceous fields; weedy, logged or burned forests; farms; Garry oak woodlands and log-strewn or stony beaches. The birds reported recently were on a sparsely treed, open ridge.
The western bluebird male has a deep blue hood and upper parts, a chestnut coloured breast and a grey belly. The female’s head and back are brownish grey, wings and tail are light blue, breast a pale reddish brown and belly and undertail a dull white. She also spots a whitish eye-ring.
Start looking for them to arrive from their winter holidays around mid-February through the first week of April, with nesting happening mid-April through May, with a possible second brood after that. They use natural cavities that are two to six metres above ground and line them chiefly with grass and bits of conifer needles, fur, string and cedar strips; gently protecting the (usually) 5 pale blue eggs. They are considered monogamous…but someone is sneaking in or out as approximately 45% of nests have juveniles of mixed parentage. Hmmmm, doing their part to keep the gene pool strong I guess. Both the male and female share the chore of feeding the young but it is up to mom to offer the comfort of her warm feathers when they are being brooded. Sometimes siblings from the first clutch will help raise second brood.…Amazingly, violet green swallows have been known to feed western bluebird chicks and help defend nests.
GOERT is offering some free nest boxes to residents who have the appropriate habitat for western bluebirds. If you feed birdseed and consequently have many house sparrows or if you have outdoor cats, then your property might not be the best location for a nest box. The nest box holes are sized so that they are right for the bluebirds and starlings can’t enter, but house sparrows can and will attack and kill the mother and babies and usurp the nest for themselves. Grey squirrels can be a problem too.
If you do find the bluebird of happiness tweeting from your trees or hunting in your hedgerows, please contact GOERT immediately.
Interested in learning more about the Western Bluebird Nest Box program? Contact moraleamilne@gmail.com or 250-478-3838 or GOERT at 250-383-3427 or bluebird@goert.ca or go to their website at www.goert.ca/bluebird
You can learn their song at: http://identify.whatbird.com/obj/150/_/Western_Bluebird.aspx
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