Over the past week I have had the good fortune to find two Broad-tailed Hummingbird nests.
The first one is in Grandview Cemetery in Fort Collins. I noticed a female making repeated visits to a little cement vehicle bridge over the New Mercer Ditch near the entrance to the Cemetery Shop (which is 150 yards south of the rock Cemetery Office at the west terminus of Mountain Avenue). Barn Swallows nest under this bridge. Maybe the hummer was after feathers swallows use for nest liner, but it’s more likely the attraction for the hummer was spider webs. Each of the 15 or so visits I witnessed involved a hover next to the bridge, then a dash into the dark underside of the bridge over the ditch water for 10-15 seconds, and then a quick exit out the opposite side from where it entered. The exit flight was always in the same direction. In the past almost all of the 30+ nests I have found at Grandview Cemetery have been on the lower branches of big Colorado blue spruce trees. I checked the nearest spruce along the vector the hummer went after bridge visits. Nothing. Then I went across a broad open area to more spruce trees on the same vector and found the nest. It was what I would call half-built on 6/18 (left photo below). The cup had enough definition for her to sit in it, spin around and shape, and it was somewhat decorated on the outside with spruce bark flakes and bits of lichens. The foundation of the nest appeared to be mostly what I think is bright white spider webbing (with a few American elm seeds embedded by the wind prior to the hummingbird’s procurement). Also, a few dandelion seeds were recognizable.
On 6/21 the nest was basically complete, with much greater depth and exterior decorating (below right). You can tell by the web debris on her beak she is still “knitting” the interior of the cup into a final configuration she likes. I do not know if she had laid eggs on 6/21, but if not, that act is imminent. If this nest is like others, she will liven up her two weeks of what must be boring incubation with continued additions to the nest exterior of a tile here and a bit of color there. This has always seemed to me a futile attempt to improve on perfection. And once the eggs hatch, mamma’s labors intensify considerably. She must feed the two nestlings, feed herself, defend/shield her progeny from heat, rain, sprinklers, incoming golf balls, fox squirrels, Blue Jays, etc. Egg hatch also marks the onset of nest deterioration. During their approximately two week-long nestling period, the young will grow, thrash around, completely fill the expandable nest to the exclusion of Mom (about half way thru the nestling period she will have to perch next to the nest to feed them). On fledging day, most nests are reduced to throw rugs with no chance for refurbishing and reuse next year.
The second nest discovered lately is in lower Rist Canyon west of Fort Collins. It is in an area I have been visiting for over 50 years to collect insects for the Gillette Museum at Colorado State University. On 6/17 I walked past a 5-foot tall Douglas-fir that will be part of the next forest on a north-facing slope at present mostly devoid of big trees due to bark beetle outbreaks in both pine and Douglas-fir and the High Park Fire of 2012. Out of the little tree burst a female hummingbird. I knew what that probably meant and, sure enough, there was a nest with two eggs a mere 3 feet off the ground (left photo below). Today, the female was on the nest (below right). Note the plum-colored gorget feathers on this female, which the hummingbird books say is rare in female broadtails. The exterior of every hummingbird nest is unique and the Rist Canyon nest has a lot more lichens and gray bark bits than the Grandview Cemetery nest.
Both genders of hummingbirds are awesome, but for different reasons. The males are gaudy, engage in exotic flight maneuvers, make a lot of noise and beg to have their pictures taken. But the females have always commanded my respect. After being impregnated, they do it all: build the nest, then all the other chores mentioned above, and even do post-fledging feeding/life training of the kids. Here’s to female hummingbirds!
Dave Leatherman
Fort Collins
