For All Seasons: A Big Bend Journal was written with two purposes in mind: to provide the reader with a day-by-day, yearlong perspective on the changing seasons in one of the most spectacular of our national parks, and to pass on details about a wide variety of personal experiences, ranging from various hikes and discoveries to out-of-the-ordinary observations and studies, a few of which were previously available only in scientific reports. The narrative runs from January 1 through December 31, in twelve monthly chapters, so that the reader can go to any one day or period of time to learn about what might occur at that time of year.
All my daily descriptions occurred from August 1966, when I first moved to Big Bend National Park, through mid-1996. I resided within the park, as chief park naturalist, until mid-1972, when I moved into the regional chief scientist position at Santa Fe, New Mexico. During the next six years (1972-1978), still involved with research and resource management at Big Bend, I visited the park regularly at various times of the year. However, after late 1978, when I moved to a Washington, D.C., assignment (chief of natural resource management), and until I retired from the National Park Service in May 1989, my Big Bend Park visits were few and far between. Since moving back to Texas in May 1989, I have renewed my involvement with the park and have begun conducting avian population research and annual bird ecology seminars. Park visits, therefore, became far more numerous. It was during these later visits, responding to numerous questions from park employees and others about the "earlier" years, that the idea of this book occurred to me. And so, during 1995 and 1996, I developed the various issues and prepared the narrative.
The actual writing of For All Seasons has been one of my most enjoyable literary efforts to date. Once I settled on the list of issues to be included, through the review of sixteen notebooks in which I had maintained detailed observations during my six-year park residency and later visits, it was all pure pleasure. I found myself recalling each experience with joy and excitement. Whether it was finding myself in the middle of a herd of javelinas, being trailed by a mountain lion after dark, encountering a territorial whip-poor-will face to face, discovering a new creature for the park, the state of Texas, or the United States, or participating in one of the park's Christmas bird counts, I relived each with relish.
In describing my numerous Big Bend experiences, I have tried to incorporate some of the same excitement that I felt at the time. Other topics, such as cactus or breeding bird surveys, are more informational in charac ter, providing details of happenings and findings that have not previously been reported. Many of these observations represent a snapshot in time and therefore provide valuable insight into a sequence of events that might otherwise be lost.
Also within the narrative, I have included the names of various friends and colleagues who shared pertinent experiences. My many hikes and numerous other activities were greatly enhanced by their participation; these folks are mentioned in the acknowledgments.
Several of the incidents described in the narrative must be placed in perspective. My residency in the park came at a time when the abundant natural and cultural resources required documentation. This often in volved extraordinary methods not normally allowed in national parks that have already been adequately surveyed and studied. For example, I maintained a bird-banding station at my Panther Junction residence and at various other times at Rio Grande Village, near Castolon, and at Boot Springs. This activity led to a better understanding of avian numbers, distribution, and length of stays. For instance, I discovered that the nonnative house sparrows at Panther Junction and the Chisos Basin were all part of one large flock; birds banded at Panther junction often fed at the now abandoned (since 1995) Chisos Mountain Remuda in the Chisos Basin. House sparrows at Rio Grande Village spent their summers, when fewer campers were present, at the nearby Mexican village of Boquillas. The operation of a banding station normally includes attracting the birds with nonnative materials, such as bird feed and a birdbath, a practice that is not normally permitted in a national park.
In addition, in recent years adjacent ranchers and other private landowners have clamped down on any visitor trespass onto their land. For instance, while access to the Adams Ranch, just east of the Dead Horse Mountains, was lax during the 1960s and 1970s, entry is now permitted only on a fee basis. It is imperative that all private lands surrounding the park be respected, and that no one enter any private land without permission from the owner.
Names of numerous locations, as well as animals and plants, are scattered throughout the text. For consistency, names of all sites within the park were derived from the Big Bend National Park free brochure or, for back country sites, the Big Bend National Park, Texas, topographic map published by Trails Illustrated (1994). All plant names, except for cacti, were derived from Michael Powell's Trees & Shrubs of Trans-Pecos Texas (1988) or, for herbaceous plants, Correll and Johnston's Manual of the Vascular Plants of Texas (1970). Names of the cacti are being revised, and so I have utilized those common and scientific names from my Naturalist's Big Bend (1980). The exception includes the ground chollas that were described by Barbara Ralston and Richard Hilsenbeck (1989).
Names of all invertebrates and fish are those utilized by the most pertinent researchers or best-known authors: butterfly names were derived from the North American Butterfly Association's Checklist & English Names of North American Butterflies (1995); amphibian and reptile names were taken from Roger Conant's A Field Guide to Reptiles and Amphibians of Eastern and Central North America (1975); bird names are those utilized by the American Ornithologists' Union's Check-list of North American Birds (1983) and supplements; and mammal names are taken from David Schmidly's The Mammals of Trans-Pecos Texas (1977).
Finally, to all my readers, whether you are long-time advocates of the Big Bend country or first-time visitors, I wish you many happy and exciting times in one of the world's most outstanding national parks.
January 1 (1967).
The new year began with an especially clear, sunny morning at Panther Junction, park headquarters and employee residence area. Dozens of wintering songbirds were present in the surrounding desert. Canyon towhees, dark-eyed juncos, white-crowned sparrows, and house finches were most numerous. There also were several pyrrhuloxias, mourning doves, and scaled quail and smaller numbers of curve-billed thrashers and green-tailed towhees. When I walked outside to breathe in the clean, fresh air, the rollicking song of a cactus wren was echoing across the desert, a greater roadrunner was chasing a lizard up the roadway, and a Say's phoebe was fly-catching from the clothesline.
I had decided to rest on New Year's Day after having recently completed three Christmas bird counts, presented two evening programs, and talked with hundreds of visitors during the previous week. The park's campgrounds had filled to overflowing right after Christmas, and all the park staff—especially interpreters, rangers, and maintenance employeeshad worked more than their expected eight-hour days to accommodate the abundant visitors. Although a crowded park taxed all of us, when a woman from Dallas told me that it was her first park visit, that she had "no idea Texas contained such gorgeous country," and that she would come back again with her grandchildren ("they need to see Big Bend National Park if they are going to grow up to properly appreciate nature and our wonderful national parks"), it made it all worthwhile.
January 3 (1970).
Robber's Roost is an abandoned ranch located at about 3,000 feet elevation along an open arroyo below Juniper Canyon. Today, Dr. Jon Barlow of Canada's Royal Ontario Museum and I visited this location in search of wintering gray vireos. This songbird had not been known to winter in Texas before I had discovered one near The Chimneys a month earlier (see December to [19691). Now Barlow, a professional ornithologist and vireo specialist, and I were attempting to locate additional individuals. Our findings were later published in the Canadian Journal of Zoology (Barlow and Wauer 1971).
Jon carried a tape recorder and playback apparatus, and he played gray vireo songs every now and then as we scouted the area. We received no answer during the first couple of hours. But finally at Robber's Roost, a male gray vireo responded. Although it first remained concealed in a thicket of honey mesquite and desertwillow, it approached to within about ten feet of us. And during the next twenty minutes it sang several typical territorial songs, three whistle-notes (second one higher than the first, and the third note lowest in pitch), one after the other, with brief pauses in between. It also gave fifteen to twenty ground squirrel-like rattle-calls, unique to the species, as it foraged among the vegetation. It finally appeared in view on the open mesquite branches, and we watched it capture an inch-long short-horned grasshopper, which it pecked apart and ate while holding the grasshopper against the branch with its right foot. Our wintering gray vireo eventually moved away up the arroyo and disappeared.
Other bird species recorded that day among the vegetation at Robber's Roost included white-winged and mourning doves; northern mockingbird; curve-billed thrasher; pyrrhuloxia; black-throated, chipping, claycolored, and white-crowned sparrows; and house finch.
January 4 (1973).
An ice storm had moved into West Texas the previous day and the temperatures were in the teens; many of the highways were dangerously slick. Vic Valezuela and I had driven our valuable cargo of Montezuma quail from their capture site near Patagonia, Arizona, to the park, with considerable concern about the birds' well-being. They were to be released in Pine Canyon, a preselected habitat with an adequate food supply, as soon as possible. But the weather could create additional stress on the birds after they had already been caged for two to four days (they had been captured at different times) and had endured a fourteen-hour drive to Texas.
By midmorning, however, the day was sunny and bright; the temperature at Panther junction, where we were holding the birds, was already in the sixties. We decided that the birds' release into the wild, where they could find adequate food, was more important than holding them for another twenty-four hours. We loaded the five cages back into the station wagon, and by about 1:30 P.m. we were at the Pine Canyon release site. All twenty-six birds were alive and appeared to be in good condition as we moved the cages to the high bank at the end of the road. (About one mile of the road has since been closed to vehicular traffic.) A few minutes later we uncovered the cages, opened the doors, and stood back, inviting the birds to leave.
It took several minutes before the first individual decided to risk it, but as soon as it was free and flying off, the remaining birds quickly followed. They all flew to the wooded canyon floor below us and totally disappeared from view. They were now on their own.
Dave Brown, biologist with the Arizona Fish and Game Department, had provided us with considerable help in their capture; he and his dogs had been essential in trapping the birds in Arizona. Dave also had visited the park to assess the habitat for suitability during the planning stage. Based upon adequate cover and a good food supply, especially oxalis in the canyons, he had recommended the project and Pine Canyon as a release site. See April 25 (1975) and February 11 (1977) for two followup surveys. Further discussion of this bird is presented in A Field Guide to Birds of the Big Bend (Wauer 1996).
January 5 (1969).
Coyotes were still "singing" as I began my walk northeast from the highway bridge across Tornillo Flat. An unidentified park visitor had recently reported sage sparrows, considered a rare winter visitor, on the sparse grassy flat, and I intended to check it out for myself. Sure enough! During a three-hour walk, in a wide, two-mile loop route, I encountered a surprisingly large number of sage sparrows. Ever since then, this species, a breeding bird of sagebrush flats in the Great Basin of western North America, has been found in this area almost every winter.
I also encountered a herd of fourteen javelinas on my walk. I was so intent on my search for sage sparrows, and also on identifying the various cactus species that might occur on these arid flats, that I did not see the javelinas until I had walked right up to them. They apparently had frozen in place as I approached, thinking perhaps that I would pass by without noticing them. Instead, when I stopped to check out a particularly large devil's head, I spooked the herd. They suddenly exploded into flight in all directions. The exception was an old boar that remained in place, about thirty feet away, sniffing the air, snorting, and pawing the ground like an Andalusian bull. The hair on the back of its neck stood straight up. I froze in place, waiting for this apparently aggressive boar to make the first move.
Within a few seconds it began a slow, rather jerky walk to my right, pausing now and then to sniff the air. I could see the abundant scars on its gnarled face and ears, evidence of many battles with other javelinas and a life among the sharp lechuguilla leaves. It continued walking, making a complete circle around me. Suddenly, apparently catching my scent, it snorted, faced me, and clacked its teeth. Its neck hairs were again elevated. I remained still and quiet; javelina eyesight is extremely poor, and they largely depend upon smell and hearing to detect danger. Soon, it continued its walk, circling me at a maximum distance of about fifty feet. Each time it caught my scent it became aggressive again, snorting, pawing the ground, and clacking its teeth. Finally, after four complete circles, it moved away, following the others across the desert and out of sight.
January 8 (1970).
Mesa de Anguila, located in the far western corner of the park, is one of the least visited parts of Big Bend National Park. Access is limited by the high cliffs of Santa Elena Canyon and the eastern escarpment west of Terlingua Creek. A trail that starts behind the little town of Lajitas to the northwest provides the best access. It makes an extended loop route on the high mesa top. I spent eight hours on the mesa today, recording all the birds I encountered and censuring the cacti.
I detected only a dozen species of birds: golden eagle, common raven, ruby-crowned kinglet, verdin, canyon and rock wrens, crissal thrasher, orange-crowned warbler, pyrrhuloxia, canyon and spotted towhees, and black-throated sparrow. I observed the golden eagle soaring above me on several occasions; it could have been either a resident bird or a winter visitor.
I also recorded fourteen species of cacti, but only one of those—foxtail cactus—was truly abundant. This neat little plant, known to science as Mammillaria pottsii, is rarely more than six inches tall and possesses many short white to reddish radial spines and six to twelve gray, dark-tipped central spines that generally are straight and protrude out and upward. Later in spring and also after summer rains, it produces lovely deep-red, bellshaped flowers that appear in a rosette near the top of the stems. Although widely scattered throughout the Chihuahuan desert in Mexico, its U.S. range is limited to the southern half of Brewster County, Texas.
I found other cactus species: tasajillo, blind pricklypear, and strawberry cactus were commonplace; purple-tinged pricklypear, Texas rainbow pitaya, and mountain cob cactus were fairly common; and I found seven other species in smaller numbers. Catclaw cactus, Turk's head, sea-urchin cactus, living rock, and golf-ball cactus were widely distributed; devil's head was present only in the lower areas; and I found Duncan's cactus only on top of the mesa. It was too early for any cactus flowers, but several individuals possessed new flower buds.
January 11 (1970).
I wandered along Terlingua Creek this morning, starting from Terlingua Abaja, the deserted village almost three miles above the mouth of Santa Elena Canyon. My principal interest was in pho tographing the ruins and obtaining a better understanding about this area of the park for a little interpretive book, Guide to the Backcountry Roads and the River, that I was writing.
Terlingua Abaja was established in about 1899 as a farming community to produce vegetables, wheat, and maize for the miners in nearby Terlingua. The remains of irrigation ditches were still evident along the creek banks. Downstream was a gauging station, established by the International Water and Boundary Commission, to record weekly records of the Terlingua Creek flow.
There was very little water flowing in the creek today. A lone, dead cottonwood tree stood out in sharp contrast, a grim reminder of the area's changing environment. The park's only native cottonwood is narrowleaf cottonwood, which once was abundant along Terlingua Creek. At the turn of the century, the extended floodplain held a gallery forest of cottonwoods. But all these were cut for use in the Terlingua mines, and the Terlingua Creek floodplain remained bare of cottonwoods for several decades. But on visiting this same area in 1993, I was amazed at the increased number of cottonwoods that were present. It appears that Mother Nature has begun to reclaim her domain and that lower Terlingua Creek may someday be dominated by cottonwoods once again.
January 14 (1971).
The remains of an aerial tramway, situated below the mouth of Boquillas Canyon, had greatly interested me since I first arrived in the park. Today I planned to photograph whatever was left of this international historic site. I began the day along the roadway below Boquillas Canyon, where one of the huge ore buckets and several pieces of cable remained. I later followed the tramway route north across the arid limestone terrain, and in the afternoon I drove to Ernst Basin, where the huge discharge terminal was once located.
Big Bend's mining history is primarily told at the Mariscal Mine along the River Road (see April 2  ), but the international tramway story is unique. The tunnels and shafts of the Boquillas Del Carmen Mining Com pany were located in Mexico, more than two miles south of the Rio Grande in the foothills of the Sierra del Carmens. High-grade silver, lead, and zinc were mined from a number of tunnels on the fractured slopes. A six-mile-long tramway hauled the ore from Mexican loading bins, down the slopes, and across the Rio Grande to the Texas terminal. The ore was then hauled by wagons, pulled by traction engines, to the nearest railhead in Marathon, approximately sixty-five miles away. Built in 1909, the tramway was capable of hauling 250 tons of ore daily.
The tramway was powered by a forty-five-horsepower gas engine at the Mexican terminal, where the ore was loaded into buckets, each with a capacity of 6.5 cubic feet. The tramway cables were one inch in diameter on the loaded side and three-quarters of an inch in diameter on the empty side. The tramway system utilized a total of thirty-six towers, including four tension stations, starting with double towers near the loading terminal, low towers on the flats, and one sixty-foot-high tower to help carry the cables over a sharp rise. The towers were approximately 800 feet apart, with the longest span of 1,300 feet across the Rio Grande. Fifteen water carriers, each able to hold forty gallons, were attached to the empty side. An intermediate station, located on the Mexican side of the Rio Grande, served as a tension and watering station. The Texas discharge station also served as the American Custom House.
I also was able to locate the company (A. Leschen & Sons Rope Company) that had designed the terminals (blueprints are dated January 2, 1908) and constructed the tramway for a Don Carlos Moser of San Antonio, Texas. Operations were terminated in 1919, when the cost of operations exceeded the revenues.
January 16 (1969).
Hot Springs Canyon, located between Hot Springs and Rio Grande Village, is but a miniature of the park's much longer and higher big three: Santa Elena, Mariscal, and Boquillas Canyons. However, the arid limestone soils at Hot Springs Canyon contain a surprising variety of low desert vegetation. Lechuguilla, creosotebush, Torrey yucca, and ceniza were most obvious, and leatherstem and Texas falseagave were present in substantial numbers as well.
My principal interest today was to census the cacti that occur on the limestone hills. I walked north from the Hot Spring junction for a quarter of a mile, identifying and counting all the species found within approxi mately three feet of a centerline. I recorded a total of eleven species, but only one was commonplace—cob cactus (Coryphantha tuberculosa). This little cactus, which occurs singly or in clumps of up to fifteen stems, is seldom more than ten inches tall and has gray-green stems that are well hidden by short and variable spines, except at the base of the plant, where the spines fall off the tubercles. The base usually is completely bare of spines, giving it the appearance of a corncob. Violet-pink flowers are borne on the tips of the stems during April and May and again after summer rains.
Eight other species of cacti were fairly common: living rock, Texas rainbow pitaya, sea-urchin cactus, dog cholla, devil's head, button cactus, golf-ball cactus, and cane cholla. I found fewer brownspine pricklypears and woven-spine pineapple cacti. None of these were in bloom, although several dog cholla and brownspine pricklypears possessed buds that would bloom before long.
January 18 (1968).
This morning at Rio Grande Village, I discovered a number of green sunfish swimming in the isolated pond that had been developed to protect the park's most famous fish species, the endemic and endangered Big Bend gambusia. The nonnative sunfish, probably placed in the pond by well-meaning fishermen, would eventually eliminate the entire population of gambusias if ignored. I immediately set in motion a number of steps to save this fragile species.
Within a couple of days, park maintenance employees began to dry up an adjacent pond that also contained a number of exotics: goldfish, mosquitofish, bluegill, and green sunfish. Once that pond was dry and we were satisfied that it no longer contained any fish, we added filtered water and allowed it to stand for about two weeks so that a natural food supply could develop. At that stage, the gambusia pond was drained, and Roger Siglin and I spent several hours seining out as many of the Big Bend gambusias as we could. We were able to collect more than 250 individuals; 150 of these were released into the new pond, and the remainder were taken to park headquarters, where they were placed in an aquarium in my office.
Once the initial pond was completely dry, we added new filtered water and allowed a natural food supply to develop (this took about thirty days). I then released the approximately one hundred gambusias being held in my office into their new home. We also built a new fence around the pond and erected a new sign that I had written:
Fish So Fragile—This pond contains the world's population of Gambusia gaigei. These minnow-sized fish have lived here since Mastodons. Unique and fragile, they survive only because man wants to make it so.
The Big Bend gambusia population immediately began to increase. They seemed to thrive, at least until further problems were detected in 1976; for these details, see May 5 (1976).
January 20 (1971).
Paul Gerrish, friend from the park, and I hiked cross-country from Cattail Falls to Blue Creek today. The route was unmarked, and we had to find our own way. My notes, written in my field notebook that day, included the following: "Start at Cattail, cross canyon (old trail on south side), then follow slope up and into lg. drainage that heads at massive Ward Mt. cliffs. Head for highest pass (at base of cliff). From Pass follow contour to ridge to south from where you can see the Ward Sp[ring] dike far below. Then a gradual descent to Sp, cont. SW, either over ridge or around to straight shot to pass and down drainage into Bl. Cr."
Bird life along the trail was sparse. Only two species were present throughout, canyon towhee and rufous-crowned sparrow. Both are permanent residents of the Chisos Mountains' mid-elevation grasslands. Somewhat similar in appearance, the larger towhee is all brown, with light underparts and a dark chest-spot, and a buff cap and undertail covert. Rufous-crowned sparrows possess a streaked back, plain gray-brown underparts, rufous cap, whitish eyebrows, and black whisker-stripes. On spring days, their songs often dominate the mid-elevation slopes: clear twosyllable "chili-chili-chili-chili" notes of the canyon towhee, and the rapid, bubbling "chip" notes of the rufous-crowned sparrow.
January 21 (1967).
The Window Trail was extremely birdy this morning. The weather was cool and bright, and it seemed to me that all the birds wintering along Oak Creek were active. I recorded thirty-seven species in about three hours, and the most obvious of these was the little black-chinned sparrow. I detected more than a dozen individuals, either by their very distinct songs or because I found them searching for seeds along the trail.
The black-chinned sparrow's song is one of the easiest of all bird songs to recognize, and, once heard, it is hard to forget. It begins with a series of "sweet" notes that are followed by a rapidly descending trill, like a bouncing ping-pong ball. The bird itself is a medium-size sparrow, mostly gray with a brown back and wings. It also possesses a black chin and face and a short, conical-shaped pink bill.
January 21 (1969).
I surveyed the cacti this morning in lower Green Gulch. My route went southwest from the Green Gulch road junction, across the grassy ridge, and onto the higher rocky slope beyond. I recorded only eight species, but two of these were commonplace, Chisos pricklypear and brown-flowered cactus. I found two species to be fairly common, cane cholla and devil's head. I recorded only a few purple-tinged pricklypears and strawberry cacti. And I found even fewer Engelmann's pricklypears and cob cacti.
The Chisos pricklypear (Opuntia lindheimeri var. chisosensis) is unique to the Big Bend area. It has grayish-green pads with widely spaced areoles, containing yellow glochids and spines that may be almost three inches in length. The cylindrical-shaped brown-flowered cactus (Echinocereus russanthus), usually solitary and seldom more than ten inches tall, has many radial spines that protrude from round areoles. True to its name, this cactus possesses inch-long, funnel-shaped brown flowers, with obvious pale yellow stamens and green stigmas. New buds circling the stem promised an early bloom.
January 23 (1969).
The Dodson Trail, a 11.5-mile route that circles the southern edge of the Chisos Mountains between Juniper and Blue Creek Canyons, is one of the park's best primitive hiking routes. Park rangers Jim Court, Gary Brandow, and Roy Allen accompanied me today, starting at the lower juniper Canyon Trailhead at 8:30 A.M. and reaching the Blue Creek Canyon parking area at 4:30 P.M. Our first stop was in about three miles at the Dodson Place, where we found two dozen javelinas that had been sleeping in the old ranch house and rooting in the nearby seep. They scattered as we approached.
The day was crystal clear but very cold. During the warmer season this hike can be extremely difficult, but the abundant views toward the east, south, and north are often spectacular. I know of no other area of the park that offers such extensive vistas of chaotic grandeur.
I found only twenty-three bird species during the entire day, but I recorded more crissal thrashers that day than at any time before or since. Apparently the heavy rains of the previous fall months had produced ade quate vegetation in the arroyos for this thicket-loving bird. At one point in midmorning, a crissal thrasher sang a three-syllable song from the top of an acacia. We all had a superb look at this long-tailed, long-billed bird. Its rust undertail covert was obvious.
January 26 (1968).
I spent the entire day banding birds at Boot Spring. Using five mist nets placed at strategic places around the cabin site, I netted, measured, banded, and released a total of seventeen individuals of seven species: yellow-bellied sapsucker, ruby-crowned kinglet, tufted (black-crested) titmouse, Townsend's solitaire, spotted towhee, rufouscrowned sparrow, and dark-eyed junco (both gray-headed and Oregon forms).
Before sunset, I walked the trail to above the Boot Canyon pouroff to photograph the evening colors on the Sierra del Carmen range to the east. I sat at the trail-side overlook directly across the canyon from the rhyolitic upside-down cowboy boot from which the area's name was derived. While I waited for the best color, more than forty common ravens appeared in a scattered flock at about eye level along the slope of Toll Mountain, a mile or more from my position. The ravens circled the upper portion of juniper Canyon once, and then they all disappeared into deep crevices on the rocky face of Toll Mountain. They apparently had a winter roost there.
January 28 (1970).
The Window Trail was extremely pleasant this morning. At about the halfway point I stopped to watch four Carmen Mountains white-tailed deer that were foraging on shrubs in the drainage below. They were sampling a variety of leaves, including white brush, Gregg ash, fragrant sumac, Texas buckeye, and skeletonleaf goldeneye. They seemed to spend an inordinate amount of time nibbling on Gregg ash. Afterward, a closer examination showed that they had been trimming away the new growth. Their nibbling undoubtedly helps shape this lovely plant.
January 29 (1967).
Yesterday I had hiked to Boot Spring and stayed overnight at the park cabin. At dawn, I birded my way upcanyon to the South Rim, where I remained for several hours, watching for whatever might pass by. Besides the regular full-time resident woodland birds, I also recorded a magnificent golden eagle that flew over surprisingly close by; a high-soaring ferruginous hawk; about thirty-five white-throated swifts; and several wintering songbirds: golden-crowned kinglet; red-breasted nuthatch; house wren; Townsend's solitaire; orange-crowned, yellow-rumped (Audubon's), and Townsend's warblers; dark-eyed (both Oregon and grayheaded) juncos; red crossbill; Cassin's finch; and pine siskin.
The white-throated swifts were most impressive. They were feeding over the South Rim, and on several occasions they zoomed by so close that I could actually feel wind from their passing. They also flew in and out of a cave below the South Rim, off to the right several hundred yards. It was obvious, after watching their actions, that the cave served as a winter roost. Although it was impossible to determine the size of the cave from the rim, I guessed that it may have housed a hundred or more swifts. White-throated swifts are able to overwinter in these kinds of locations, coming out to feed during mild days when insects are flying but staying out of the weather in a state of semihibernation during cold spells.