Timings and transitions

 

On our recording trip this last spring, Lang Elliott and I stopped by a beautiful area of Sonoran Desert, east of Roosevelt Lake, known as Cherry Creek.  I’d never heard of it before, but was instantly struck by its rugged beauty.  Cherry Creek, and nearby Coon Creek, are lovely drainages with rich riparian areas lined with cottonwoods and ash trees.  Just outside of the riparian zone is classic Sonoran Desert vegetation, of mesquite, creosote bush, many varieties of cactus, and, of course, the iconic saguaro.   Riparian areas in the desert are magnets for all kinds of wildlife and definitely hotspots for birds.

We arrived at the cusp of spring, for the birds anyway, as the spring migrants were just arriving and getting ready for breeding.  Our first camp was along Cherry Creek, where we pulled off into some mesquite scrub.  Warblers and cardinals called from the scrub, so in spite of the breeze, a herd of cows, and lots of commercial jets overhead, things looked promising.  Not far from camp, I found a spot where little Cherry Creek had been impounded by a small, human-made dam.  Curious what might be attracted to this pond, we set up our mics.  It was a lovely spot, and I got this nice, relaxing recording of calling insects, the breeze in the cottonwoods, and distant western screech-owls and great horned owls:

 

The next morning we moved over to Coon Creek, which provided more shade and a nice little creek for us to stick our feet in during the heat of the day.  The tall cottonwoods were loaded with yellow and Lucy’s warblers and summer tanagers.  But the noise of the stream and the whisper of the cottonwoods made it a little difficult to get a clean recording.   Lang had scouted out some nice quiet little side canyons, which would lack the excitement of the riparian areas, but might provide some nice quiet desert recordings.

The first spot was a small rocky canyon, lined with mesquite with large saguaros growing among the rocks.  It turned out to be a very quiet spot with most of the wildlife a long way away.  But a baby great horned owl landed nearby, and practiced hooting for awhile, mixed in with baby-squawks.  An adult owl can be heard in the distance.

The second spot was a more open canyon, which drained into another artificial impoundment.  It was dry, but the mesquites and other brush in the area seemed to be teeming with birds.  And it turned out to be a very active spot, with nesting elf owls nearby that vocalized almost all night long.  Toward dawn, many other species also chimed in, with the result being a wonderful transitional recording, documenting not only the fading of night and the beginning of the day, but the ending of winter and the beginning of spring:

Several of the birds calling have just arrived for the spring breeding season (elf owls, white-winged doves, ash-throated flycatchers), while others are resident (great horned owl, curve-billed thrasher, Gambel’s quail, cactus wren, gila woodpecker, mourning dove) and singing to attract mates.  Lastly, there are one or two who wintered in the area, and have not headed north yet to breed (Brewer’s sparrow, black-throated sparrow  – which also may breed in the area).  Catching the Brewer’s sparrow singing their winter song, instead of their long, drawn-out summer song, was quite a treat.

I’ve long been fascinated by these transitions, with the changing of the leaves in autumn being my favorite.   The last few years of sound recording have made me realize what a great tool recording is to monitoring these transitions and increase my awareness of what is going on in the natural world around me.  Listening is a continual reminder that every species, every individual, is on its own life trajectory, with its own timings and transitions between life events.

Critter of the Month

So the Critter of the Month is the curved-billed thrasher (the loudest bird in the last recording).   Toxostoma curvirostre is a common bird in the southwest deserts, and their range extends down through most of Mexico, and eastward to the Colorado plains.  Like most thrashers, they make their living by scratching through leaves and debris on the ground looking for insects, but will occasionally fly up into the brush or low trees after butterflies or moths, or to snack on fruits like hackberries.  They also like cactus fruits.  They are easily recognized by their yellow-orange eyes, and their piercing “whit-wheet” call, which they give year-round.  They also have a lovely warbling song, full of repeated phrases somewhat like a mockingbird.  The song is usually only heard in early spring, and they often stop singing once the eggs have been laid.

When I lived near Tucson, I shared my yard with at least one resident pair of curve-billed thrashers, and loved watching them.  They nested in a neighbor’s cholla plants, and while I couldn’t see the nest from my house, I often saw them zipping low through the vegetation, bills full of moths or other insects.  Once I watched a couple of fledgling thrashers chase each other around the base of an agave, looking like they were playing tag. 
 Another time, I heard a very agitated thrasher growling at something in the brush.  I approached to check it out, and discovered a red racer curled up at the base of an agave.  Snakes are one of the primary predators of thrasher eggs and nestlings and the adult thrashers will aggressively defend their nests against them.  This thrasher repeatedly darted in to try to poke the snake, which tried to get further under the agave.  I didn’t stay to see the end of the lengthy encounter.

For more about curve-billed thrashers, see:

https://www.allaboutbirds.org/guide/Curve-billed_Thrasher/overview