Tuesday, January 6, 2009

Birds in the Bush

You may think the above photo is a rather boring view of dull shrubbery. But if you had been there to hear the exuberant chatter of dozens of sparrows concealed in the leafy shadows, you might think otherwise. A few quiet steps towards the avian hideaway, and the chatter ceases. Another few steps and the bushes erupt in a wild frenzy of feathers, leaving a few bits of down drifting in the morning air. The flock wheels around in a synchronized aerial ballet and settle down in some identical shrubbery up the wash, disappearing as quickly as they emerged. Magic.

This was a highlight of my own personal annual bird count in our neighborhood this week. On January 2nd I participated in an "official" Audubon Society Christmas Bird Count in a wash called Camp Creek in the nearby Tonto National Forest (which is really mostly a desert, not a forest). Comparing the two counts is an interesting exercise for me, and actually makes me feel quite lucky to live where I do, at least bird-watching wise.

Living on the suburban fringe, the diversity of birds we see is influenced by the "edge effect." In this case, we have the melding of two distinctly different ecosystems that host a variety of species. Our neighborhood includes a 640 acre desert preserve called Deem Hills to the north. Birds wander from the pristine desert to mix with flocks that thrive in the vast urban wilderness of Phoenix. In the developed part of the neighborhood, irrigated lawns and perennially flowering landscapes attract more hummingbirds, killdeer, and grackles, while the more remote desert is the refuge of species that favor native plants, such as phainopepla and Abert's towhee. Urban adapted species (i.e. species that tolerate or even prefer landscapes influenced by humans) are less likely to move into the less hospitable wild desert, whereas all of the desert natives I observed deep in the National Forest last week have occasionally been seen wandering into the housing area, with the exception of a few higher elevation species we saw, like Western Bluebirds and Ruby-crowned Kinglets.

Other differences between the two surveys are that whereas I was one pair of eyes searching for three hours, our Audubon count had three pairs of eyes roving for six hours. And, as mentioned above, there is about 2000 feet elevation difference between the two locations. This translates to slightly different vegetation in the two desert areas as well, with jojoba abundant in the higher Tonto, plus a large wash hosting sycamore and cottonwoods. Of course, the suburbs are a cacaphony of vegetation from all over the world, and probably ten times the water.

Our final tally for the Tonto count was 26 species and about 200 birds. In my neighborhood, I listed 20 species and over 300 birds. The higher numbers down in the suburban fringe were largely from Gamble quail, which travel in coveys of over 50 and house sparrows, which gather in similar numbers. For some reason I haven't yet figured out, we did not see a single quail up in the Tonto. In the end, I suspect that if I had the additional eyes and time to match the Audubon group for the neighborhood tour, we could definitely match the diversity and double the numbers as well.

Which brings me back to another point. Ears are equally, if not more, important as eyes to successful birdwatching. Most of the time, it is the song or call or rustle of a bird that attracts my attention than the actual sighting. Especially for those little guys that hide in the shrubs.

For anyone who is curious, here is the entire list for both bird counts. My prize was the sharp-shinned hawk stalking the sparrows in the shrubs above, right in my back yard! What's flying around in your back yard?

Camp Creek Deem Hills
1 Say’s Phoebe 1 Say’s Phoebe 1
2 Gila Woodpecker 6 Gila Woodpecker 4
3 White-crowned Sparrow ~75 White-crowned Sparrow ~25
4 Black-throated Sparrow ~5 Black-throated Sparrow ~100
5 Blue-gray Gnatcatcher 1 Blue-gray Gnatcatcher 5
6 Mockingbird 10 Mockingbird 3
7 Verdin 7 Verdin 6
8 Cactus Wren 4 Cactus Wren 7
9 House Finch 5 House Finch 15
10 Curve-billed Thrasher 2 Curve-billed Thrasher 5
11 Costa’s Hummingbird 1 Costa’s Hummingbird 7
12 Canyon Towhee 3 Canyon Towhee 2
13 Phainopepla 15 Gambel's Quail ~120
14 Abert’s Towhee 6 Rock Dove (aka Pigeon) ~20
15 Western Bluebird 7 Mourning Dove 9
16 Cardinal 4 Boat-tailed Grackle 2
17 Junco 5 House Sparrow ~100
18 Raven 15 Northern Flicker 2
19 American Kestrel 1 Sharp-shinned Hawk 1
20 Scrub Jay 6 Killdeer 2
21 House wren 2
22 Red-tailed Hawk 2
23 Goldfinch 1
24 Rock Wren 2
25 Spotted Sowhee 1
26 Ruby-crowned Kinglet 1
Total 187/26 310/20

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