Birding By Habitat: Discovering the Birds and Botany Connection

By Rich Hoyer

Through the transformational learning experience of the point count survey, Rich Hoyer developed a sense of how the Grace’s Warbler chooses its habitat. Photo by Hemant Kishan.

For the first ten years of my birding life, I enjoyed keying out plants as I went birding in exciting new places throughout the American West, but never connected birds and plants until I moved to Southeast Arizona. Here, on my first post-university job with the United States Forest Service, I was required to do point counts as well as know all of the trees and shrubs. Within a week or two of starting the surveys, I had gone through a transformational learning experience and began to look at birds and their habitats in a new light.

We conducted our surveys at about 340 permanently marked points randomly located along straight-line transects at various elevations in five of the largest sky-islands (Santa Catalinas, Santa Ritas, Huachucas, Pinaleños, and Chiricahuas). We were required to visit each point three times during the breeding season, and after early July we began the complex and often tedious job of habitat measurements. But it sure beat sitting in an office or classroom!

Black-throated Gray Warbler, Shawn Cooper

As I arrived at each survey point, I would be tense with anticipation, wondering which species I might get during the seven-minute count. I may have hiked only three hundred meters from the previous point, but it was like a game: soon I found myself getting better at predicting the precise mix of species. At some points only five species would be singing, but at others, where there was clearly higher plant diversity, there would be more than 20 species. I was scribbling on the data entry sheet frantically, making sure I recorded every individual.

The mix of species and the numbers of each was always different. I detected Black-throated Gray Warbler almost everywhere, but I noticed that they were missing from those points too high or too low where no oaks were present (it didn't seem to matter which kind of oak, and there were about eight species). Sometimes the transect would cross over a ridge from a south-facing slope to the north side, which was cooler and more moist. An open woodland dominated by small, scattered Arizona White Oak would suddenly become a shady forest with taller trees and the addition of Silverleaf Oak and Douglas Fir. Here I would have my first Painted Restart of the morning. On to the next point, where a singing Grace's Warbler would be new, within sight of the first tall Chihuahuan Pine on the transect.

Painted Redstart, Shawn Cooper

I learned over time that while some birds honed in on specific trees, it was often the general shape of the habitat that defined what a particular bird species found most attractive. The slope of the ground, the amount of leaf litter and grass cover, the density and size of trees and bushes, and the varying density of cover at different heights above the ground all contribute to give a habitat its shape. A bird feels most comfortable in the habitat where it can most successfully forage, nest, roost, and keep from being preyed upon.

Bushtit, Mick Thompson

I am still learning which birds prefer which habitats, especially when I visit a new site. Seeing a large flock of Bushtits foraging in waist-high desert shrubbery in the eastern outskirts of Albuquerque was a new experience for me. I did then notice that scattered on the slopes nearby were oaks—apparently Gray Oak is the common one there. Bushtits don't need oaks (they occur in many areas where there are none), but my experience from twenty years ago in Southeast Arizona points to a connection, at least here in the Southwest. There is still a lot to learn!

Rich Hoyer is a full-time trip leader for WINGS Birding Tours.