Ted Floyd reported bushtits nest building at Greenlee Preserve near Boulder yesterday. I can add a report from Fort Collins. Also yesterday, I was quite surprised to see bushtits building a nest from the front door of my apartment. I live about a mile east of CSU in an older residential area. The nest tree is actually on the property to the south, which hangs over the boundary fence to our complex. The nest is about 20 feet up on the east side (gets the morning sun) of a very large Colorado Blue Spruce. BNA says nest construction can take anywhere from 2-7 weeks to complete and that spider webs are integral to their construction. This nest is well enough along to have the general ball shape of a finished nest but is still very well concealed within the spruce needles.
What the BNA account doesn't reflect very well is the current permanent range of this bird. The range map is what I would call the 1980 range map when bushtits were mostly on the far West Slope and regularly along the Front Range only south of Colorado Springs. Definitely a change. The extent and timing of their expansion seems to parallel quite closely that of black-chinned hummingbird. Both birds now extend northward into southern WY. Will be interesting to see what BBA II shows.
As an additional note, we need to figure out the new foods that have allowed this expansion to be successful. I have personally seen them getting Kermes scale insects from oaks at Denver Botanic Gardens, various aphids at the PERC Gardens at CSU, hackberry gall-making psyllids at Grandview Cemetery in Fort Collins, and my friend Doug Swartz here in Fort Collins showed me hawthorns full of mealybugs that he has observed often host bushtits. At LCC in Lamar they are often in tamarisk (getting aphids and attendant lacewings?). In my apartment complex they are often in junipers which I know have aphids. I suspect they are also getting boxelder psyllids.
Dave Leatherman
Fort Collins
What the BNA account doesn't reflect very well is the current permanent range of this bird. The range map is what I would call the 1980 range map when bushtits were mostly on the far West Slope and regularly along the Front Range only south of Colorado Springs. Definitely a change. The extent and timing of their expansion seems to parallel quite closely that of black-chinned hummingbird. Both birds now extend northward into southern WY. Will be interesting to see what BBA II shows.
As an additional note, we need to figure out the new foods that have allowed this expansion to be successful. I have personally seen them getting Kermes scale insects from oaks at Denver Botanic Gardens, various aphids at the PERC Gardens at CSU, hackberry gall-making psyllids at Grandview Cemetery in Fort Collins, and my friend Doug Swartz here in Fort Collins showed me hawthorns full of mealybugs that he has observed often host bushtits. At LCC in Lamar they are often in tamarisk (getting aphids and attendant lacewings?). In my apartment complex they are often in junipers which I know have aphids. I suspect they are also getting boxelder psyllids.
Dave Leatherman
Fort Collins
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