This is written as first published in the Phainopepla in November 2001:
I spent my Spring working on a nest monitoring project for Dartmouth College. I was one of two field technicians and three interns. We studied two ground-nesting species: Spotted Towhee and Rufous-crowned Sparrow, and two shrub nesters: Wrentits, and California Towhee. Of the sixteen sites studied, some where "interior plots" where no urbanization was present, other plots had urban development on one or more edges. The purpose of the study was to determine the effect of urbanization and fragmentation on nesting survival.
Of the ground nesters, the Rufous-crowned Sparrows were the hardest to locate. The were extremely secretive. If we were lucky enough to spot a female with nest material, she would apparently spot us first, vanish and not return for up to two hours. When going to a completed nest, they tend to run on the ground rather than fly directly to it. While incubating, they sit tight on the nest, not flushing until the nest is literally almost stepped on. The Spotted Towhees are just a bit easier to find. When a female is seen building, she continues to build actively. Once incubating, however, she generally stays on the nest for two to three hours. At this point, the male would "escort" her around to feed and then back to the nest.
Of the scrub nesters, California Towhees are by far the easiest and most abundant nests to be found. Although we rarely witnessed a female building, their nests seemed to magically materialize. We joked that some other bird must be building their nests for them. I seem to have formed some sort of psychic link with the Cal Towhees as I began finding their nests whether I was looking for them or not. The male would choose a lookout perch, and once I found it, I could easily walk right up to the nest, as it was always nearby. My crew was convinced I was using "the force" to find nests. I convinced them that my powers were not from the dark side. The Wrentits were similar to the Spotted Towhees in that they built right out in the open. I felt that if I had offered nest material in an outstretched hand, they would have gladly taken it. They were different from the other species in that both sexes shared the nest building task. I also learned that they mated for life, and often saw them affectionately grooming one another.
The nests themselves were quite amazing to look at, each one like an intricate work of art. They were made of a variety of vegetation and various other materials. Most were found in some sort of sage, but many were built in other plants such as monkey flower, viguiera, buckwheat, and one pair built in a patch of thistle. The nests were constructed with grasses, bark strips, leaves, flowers and the like, and sometimes man-made objects. The Wrentits found spider webs essential to their nest building. I found it quite interesting that two of my Wrentit nests on the same plot contained white ribbon intertwined through them. The source of the ribbon was from many balloons on the plot that had the ribbon tied to them as a "handle". I saw several blue and purple ribbons about the area and thought it odd that both birds chose only white for their nests. One plot, nicknamed "the dump", was the final resting place for discarded couches, stoves and the like. The local birds seemed to take it in stride, though. A California Towhee nest incorporated a cotton swab in it's nest wall. In another instance I observed Bushtits picking stuffing from a dead couch for their nest. The most exotic nest I found was built by a Cal Towhee. Each time I checked it, it was larger and more elaborate, even after the female began incubating. She added feathers and so many foxtails that they stuck out at every angle, making the nest look like some outlandish hat. She finally added a stick with dead leaves that she stood up in the rim of the nest, so it resembled a mast and sail. I dubbed it "the boat nest". It was eventually depredated, probably due to its size and flamboyance.
Checking the nests brought more surprises. We found many of the birds to be quite stubborn about leaving the nest so we could count eggs and chicks. The Wrentits held out the longest; we had to resort to flicking their tails to get them off the nest. Some still didn't budge, and a few even decided to peck at our fingers. I realized just what dedicated parents they were when I found one of their nests had tipped over on its side. The parents had made a bad building choice; the vegetation was not strong enough to support the weight once the chicks had hatched. When I found the nest in this condition, I assumed it was empty. Peering over the side, I was quite startled to see a little head poking out sideways from the nest. Apparently one chick remained, and the parent had sort of wedged itself into the nest and was adamantly brooding despite the nest's imminent collapse.
Most of the nests we monitored belonged to our target species although we monitored any nest we found. Other species included the Californina Thrasher, Western Scrub Jay, Northern Mockingbird, Bushtit, Bewick's Wren, Anna's Hummingbird, and one migrant, the Lazuli Bunting. By the end of the season we had found a total of some 300 nests, as well as a great respect for the little birds that built them.
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