Field Notes on Nesting Golden-crowned Sparrow

by Bryce W. Robinson

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Figure 1. Female Golden-crowned Sparrow – Zonotrichia atricapilla.

One of the perks of conducting research on Gyrfalcon’s in western Alaska is the time in the field to experience and study Alaska’s unique and diverse avifauna. I had never found the nest of a Golden-crowned Sparrow (Zonotrichia atricapilla) (Figure 1 & 3) until recently. The nest was at the base of a small willow shrub on a sparsely vegetated hillside dominated by lichen covered tundra. It was constructed of grass, was situated on the ground, and contained five eggs (Figure 2.). The egg color was a greenish blue with reddish brown splotching evenly spaced, but densely concentrated on the broad end of the asymmetrical elliptic egg (Figure 2).

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Figure 2. Golden-crowned Sparrow nest. Note the Musk Ox guard hair in the bowl of the nest.

One thing I missed in the hurried attempt to photograph the nest and leave quickly was the hair in the bowl. It appears that the sparrow used the coarse guard hair of Musk Ox to line the nest bowl. Nests display the architectural and creative genius of birds. I am fascinated to see materials such as Musk Ox hair used in a nest, particularly in only one section such as the bowl. The area where I found the nest was covered with the fine wool from a Musk Ox, termed Qiviut. Why the bird did not use this fine wool, and chose coarse guard hair is enough to wonder upon.

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Figure 2. Female Golden-crowned Sparrow – Zonotrichia atricapilla.

While I was investigating the nest, the female remained close. I was impressed by her vigilance. She was anxious to continue incubating her clutch. I took her vigilance as a signal that my presence needed to be short, so I recorded the information I needed and quickly retreated. It’s an invaluable opportunity to be in such a place, where many unique and understudied birds are nesting all around. Truly, I’m in a field lab ripe for study, and I can’t take that for granted.

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