Western Bluebird (OR1)
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This is the first nest attempt from this site this year.
Species: Western Bluebird (Sialia mexicana)
Location: Newburg, OR
Status: All four young successfully fledged on June17th!
Location: Newburg, OR
Status: All four young successfully fledged on June17th!
Cam Highlights:
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June 17 - The first brave nestlings fledges the box early this morning. |
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Three nestlings remain huddled in the corner, not looking like they are ready to leave just yet. Within a few hours of each other, the three nestlings spread their wings and take their first flights outside the box! |
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One more to go.... |
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And that is the last we see of them.... |
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June
15 - The parents use food to entice their 18 day-old nestlings to peek
out the entrance hole. This also gives the young birds a chance to
examine the world outside their nest box. |
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June 12 - The adults are still
busily feeding the four remaining nestlings. |
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June
11 - Tragedy! One of the nestlings died sometime this afternoon, and
here we see the adult inspecting it. The last image of all five
nestlings begging for food was around 1:30p, and images from around
2:30p still show all five heads. By 3:15, however, one nestling is seen
dead at the bottom of the nest box. |
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June 10 - This image reveals for us the plumage detail of one of the nestlings. |
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June 9 - The five
nestlings are now 12 days old, and the adults are busy feeding
them. The daily energy requirement of five Western Bluebird
nestlings that are 9-12 days old totals approximately 75 grams of
insects a day. |
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June 8 - The Violet-green Swallow has not yet returned, and all looks to be back to normal inside this nest box. |
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June 7 - Look closely at this image and you will see what appears to be a Violet-green Swallow tucked into the nest, under the nestlings. The swallow stayed in the nest in this position for more than five minutes. |
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June
6 - Now nine days old, the nestlings are able to regulate their own
body temperature. The female may continue to spend nights inside the
box, but this is more for protecting them than keeping them warm. |
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June 5 - Our IR camera illuminates the box for some interesting nighttime viewing. Here we see the female entering the box with food at nearly 10 PM. However, it is widely believed that most songbirds do not forage or feed at night. |
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June 4 - The camera captures the unmistakable headshot
of a European Starling, a non-native species and fierce competitor of nest
boxes. Luckily the 1 1/2" entrance hole prohibits the starling from
entering the box. |
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June 3 - The nestlings anticipate a feeding, but instead the female enters to box to remove a recently deposited fecal sac. |
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June 2 - One of the lucky nestlings will soon be rewarded with what looks like a plump caterpillar larvae. |
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June 1 - One of the first pictures that captures all five gaping mouths! |
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May 31 - Interestingly, when feeding young, the diet of adults shifts so that they feed heavier prey to their young and take in lighter prey themselves. |
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May 30 - Both the male and female feed young, with no apparent difference in feeding rates. |
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May 29 - Western bluebirds are altricial at birth, meaning they are essentially naked; their eyes are closed and aside from opening their mouth to feed, are unable to move. |
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May
28 - Hatching Day! Once the female left the box, it was revealed that
three of the five eggs had hatched early this morning. May 28 - Feeding has already begun and the male drops in to assist the female. May 28 - By midday, four eggs have hatched. May 28 - Finally, nearly 13 hours after the first egg hatched, the last of the five hatches! |
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May 27 - Like all bluebirds, Western Bluebirds are multi-brooded, meaning they typically raise 1-2 broods per year. In Oregon, three clutches occur with some regularity. |
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May 24 - In Oregon, the Western Bluebird is listed as "sensitive." The introduction of nest box trails has increased the population especially where suitable habitat (park-like forests, edge, and burned areas) exists. |
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May 23 - Aside from peeking her
head out the entrance hole to get food from the male, this female has
been extremely diligent about staying on the eggs—so much so that many
viewers thought the camera was stuck! |
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May 22 - We are about half way through incubation, which puts the estimated hatch date of May 28th or 29th! |
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May 19 - It is typical for the male to feed the incubating female, but our camera has captured very little feeding by the male. |
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May 17 - The average Western Bluebird egg is 21 mm long x 16 mm wide and has a
mass of just over 2 grams. |
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May 16 - Western Bluebird incubation periods last between 12 and 18 days with an
average of 14. In the female's absence the male may guard the eggs as he is here. |
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May 15 - The female began incubating with consistent timing today. With no new egg arrivals, we can assume that the clutch is complete at 5 eggs. |
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May 14 - The pair has reached the Eastern bluebird average of 5 eggs. The female will begin begin incubating today or tomorrow if this is the completed clutch. |
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May 13 - She is consistent, this female has laid all four of her eggs between 7 and 8 AM West Coast Time. |
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May 12 - The third egg has arrived, just as planned! |
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May 11 - The second egg was laid this morning just before 8:00 AM West Coast Time, she will lay one egg a day in the morning until the clutch is complete. |
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May 10 - Some time before 10 AM this morning the female laid the first egg! |
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May 8 - Common Western Bluebird natural nest sites are cavities in pine, oak, aspen, willow, sycamore, and cottonwood trees. |
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May 7 - Male Western Bluebirds have blue throats with chestnut breasts and gray underparts, while the Eastern Bluebird male has a reddish brown throat with off-white underparts, and no chestnut coloring. The male Mountain Bluebird is longer in shape and duller overall with no chestnut. |
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May 6 - Female Western Bluebirds have grayish throats and underbellies while the Eastern bluebird females have cinnamon/rusty orange throats and underbellies. Female Mountain bluebirds tend to be more pale overall. |
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May 5 - The favorite nest site for Western bluebirds is tree snags and then live trees, but they will readily use nest boxes like this one. This makes logging of old trees a real threat to Western bluebird populations. |
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May 4 - We have our first shot of the pair in the nest together. They have been very busy putting finishing touches on the nest in the last few days, a process that usually lasts between 4 and 12 days. |
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May 3 - Egg laying should begin within a day or two after the nest is completed to the satisfaction of the female. |
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May 2 - Here the female uses her belly and chest to form the nest cup. This will ensure a perfect fit for incubation. |
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April 25 - Western Bluebirds are extremely sexually dimorphic. Females have some blue on their wings and tail, while the rest is a dull gray. Males are a deep cobalt with a chestnut breast. |
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April 24 - Unlike Eastern Bluebird males, Western males do help with the nest building process. The bulk of the work is still done by the female, but the male does give some assistance in gathering material. |
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April 22 - The brilliant male is inside the box, suggesting that we have a mated pair. |
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April
19 - The female Western Bluebird holds a piece of grass in her
mouth—one of hundreds she will bring into the box to form the nest. |