Dinosaur National Monument Colorado and Utuh

A bright yellow-breasted bird suddenly arose from the riverside thicket, flew straight up 20 to 25 feet (6-8 m) above the vegetation, and then, with wings flopping, tail pumping, and legs dangling, floated back to the same place from where it had first appeared. It sang a remarkable song during its descent, a jumble of whistles, clucks, mews, squawks, and gurgles. A moment later, it let loose with a series of "kuk kuk kuk" notes, very different from any it had produced in flight. I watched it through my binoculars as it preened itself, ruffled its feathers, and then began a completely new series of clucks, mews, yanks, and gurgles. Suddenly, it shot back into the air, and I watched a repeat of its earlier territorial display.

The yellow-breasted chat is an amazing bird. It is one of our most vocal warblers, singing vigorously during mornings and evenings and sometimes late into the night. Its singing behavior is often compared with mockingbirds. One of the best descriptions of the chat was made by Percy Taverner in a 1906 Bird-Lore article: "With his stealthy elusiveness, with outpourings of song and fund of vituperation, the Chat is a droll imp. He is full of life and boiling over with animation. It bubbles out of his throat in all manner of indescribable sounds. He laughs dryly, gurgles derisively, whistles triumphantly, chatters provokingly, and chuckles complacently, all in one breath."

The yellow-breasted chat is a bird of the dense thickets that occurs along Dinosaur s rivers and tributaries. It can be loud and obnoxious in spring but quiet and secretive by summer and fall. Riverside campers often find that this large, bright yellow warbler serves as an excellent alarm clock.

Its status in the family of wood warblers was recently verified by DNA studies, in spite of its possessing a number of "unwarblerlike" characteristics: a larger overall proportion, a heavy and more curved bill, shorter and more rounded wings, and the ability to hold food with one foot.

But whatever its taxonomy, its bright yellow throat and breast, set off against its olive-green upperparts and white chin and spectacles, give it a distinct appearance. Add its unique territorial display and vociferous characteristics, and no one will question its very special status.

The Tark Environment

Dinosaur National Monument is a multidimensional park; one's perspective is shaped by one's approach and use of its resources. River users see the park from the bottom up and learn first to appreciate the flowing rivers, exciting rapids, and patches of lush riparian growth with dramatic backdrops of multicolored walls. Visitors to Dinosaur Quarry and Split Mountain learn of the geological and paleontological significance of the monument. And those folks who visit Harper's Corner Scenic Drive receive their introduction from the top of the park, which is dominated by broad, gray-green sagebrush flats and scenic vistas. Elevations within the park range from 4,735 feet (1,443 m) near the quarry to 9,006 feet (2,745 m) at the summit of Zenobia Peak.

The centerpiece of the park is the confluence of two impressive rivers, the Yampa and Green. The Yampa River flows into the Green River very close to the geographic center of the park. The Green River is impounded above the park by Flaming Gorge Dam, but the Yampa River is free-flowing. It represents the only remaining large tributary in the entire Colorado River system that remains undammed.

Riparian growth along the rivers and side canyons varies greatly but generally is dominated by cottonwoods, especially Fremont Cottonwood that may occur in large open groves if space allows, and willows, boxelder, and the nonnative tamarisk. Adjacent flats usually possess sagebrush communities where big sagebrush, rabbitbrush, and two kinds of grasses are dominant: the native ricegrass and the nonnative cheat grass.

Pinyon-juniper woodlands, dominated by pinyon pine and Utah juniper, occur on rocky slopes from just above the riparian zone to 8,500 feet (2,590 m) elevation. Big sagebrush, rabbitbrush, and mountain mahogany are common within these short-tree woodlands. Sagebrush communities dominate the open flatlands between 5,000 and 8,000 feet (1,524-2,438 m). Sherel Goodrich and Elizabeth Neese, in Uinta Basin Flora, described five rather distinct sagebrush communities resulting from slope and elevation differences.

Ponderosa pine, Douglas fir, and aspen communities occur above the pinyon-juniper woodlands in scattered localities. The Harper s Corner Trail, which follows a high ridge to an outstanding view into Whirlpool Canyon of the Green River, provides one example where pinyon-juniper occurs on the warmer south-facing slope and Douglar-fir and associated flora dominate the cooler, steep, north-facing slope.

The park s visitor center and administrative offices are located along Highway 40 near Dinosaur, Colorado, at the entrance to the Harper s Corner Scenic Drive. A second visitor center is located at Dinosaur Quarry, just north of Jensen, Utah. Each center has an information desk and sales counter; bird guides and a park checklist are available. Interpretive programs, including evening talks and ranger-guided walks, are provided during the summer season. Schedules are available at all the information stations for the asking. An informative newspaper, Echoes, is also available at no charge.

Additional information can be obtained from the Superintendent, Dinosaur National Monument, P.O. Box 210, Dinosaur, CO 81610; (303) 374-2216.

"Bird Life

Although the yellow-breasted chat is the flood plain s most exciting summer resident, it has several neighbors that also are loud and colorful. A visit to Green River or Split Mountain campgrounds, or Echo Park and Jones Hole, will likely result in finding most of these riparian specialties. In a little over two hours at Green River and Split Mountain campgrounds one morning in mid-May, I recorded 28 species.

Lazuli bunting males appeared like small, bright jewels among the riverside thickets. Their bright turquoise heads and throats gleamed in the morning light. With their bluish backs, white bellies, and cinnamon sides, they were most distinguished. Their name is very fitting; it is derived from lapis lazuli, an opaque, azure-blue to deep-blue gemstone of lazurite, according to Webster s. Females are brownish birds with darker wings, lighter underparts, and bluish rumps. But both sexes were active and easily observed. I watched one especially bright male chase another male away from a patch of saltbushes where I assumed it was nesting. I made a few sharp chip sounds, and almost immediately a female appeared out of the saltbush thicket and chipped back at me, as if agitated by my presence.

A moment later the male lazuli bunting burst forth with song, as if to help solidify its territory against this human intruder. I marveled at its bright and rapid song, a series of varied phrases that John

Terres described as "see-see, sweert, sweert, sweert, zee, see, swert, zeer, see-see." During the 15 to 20 minutes that I watched these lovely and rather aggressive birds, the male sang from several levels: on the low saltbushes, from the lower branches of an adjacent cottonwood, from the top of an adjacent utility pole, and from the apex of a taller cottonwood tree. The female stayed among the dense shrubbery but proclaimed her territory with loud and hard chips.

The numerous cottonwoods within the campground were literally alive with birds. Most numerous were western kingbirds, house wrens, American robins, blue-gray gnatcatchers, and northern (Bullock s) orioles. I counted more than 20 western kingbirds at the Green River Campground, either chasing one another among the high foliage, singing from the higher branches, or performing wild courtship flights. Paul Ehrlich and colleagues report that males perform frantic courtship flights: "darting into air, fluttering, vibrating feathers, and trilling." A separate flight song was described by Scott Terrill in The Audubon Society Master Guide to Birdingas "a pkit-pkit-pkeetle-dot or pkit-pkit-deedle-ot, which is highest pitched." Numerous individuals produced loud, sharp, "kit, whit," or "pkit" calls. The western kingbird is a lovely bird with a yellow belly, grayish throat and breast, gray-brown back, and black tail with distinct white edges. The white edges on the tail are its most distinguishing features; its look-alike cousin, the Cassin s kingbird that normally occurs farther south, lacks the white tail-edges, but possesses white at the tip of its tail as well as a darker breast and back.

A duo of tiny, all-brown house wrens sang their rapid, bubbling songs from the tip-top of two cottonwoods. Two pairs of blue-gray gnatcatchers were busy among the lower branches of the trees; they sang high-pitched, buzzy songs, very insectlike. American robins were also in full song; they produced loud, rich caroling that has been described as "cheerily-cheery-cheerily-cheery." Located 5 feet (1.5 m) up in a big sagebrush near the campground entrance, I found a robin nest with five bright blue eggs. The female flew off the nest as I approached, scolding me with sharp "tut, tut, tut" notes.

I discovered a partially constructed northern oriole nest in the outer foliage of one cottonwood tree, approximately 25 feet (8 m) up. Most of the orioles seemed too busy chasing one another about the trees to spend any time nest-building. These large black, orange, and white birds could hardly be ignored for their aggressiveness. The male northern oriole is a lovely bird. In the sunlight its orange underparts and face, black back and throat, and broad white wing bars give it a tropical bird appearance. Females are much duller, with yellowish heads and whitish underparts. The plumage of immature males is a combination of both adults. They possess the black chins and yellow-orange underparts, but their backs are only beginning to darken. All three patterns of this gregarious species were present; all were chasing one another about the Green River Campground. The partially completed nest was a finely woven, oval-shaped cup about 6 inches (15 cm) deep. I watched the adult female carry grasses to the nest, which she wove into the thin matrix. Later, she will line the cup with plant down, mosses, and animal hair.

Another bird in surprising abundance in the Green River Campground was the European starling. This large and aggressive nonnative species is a cavity-nester and seemed to be utilizing most of the choice nesting sites. I wondered how many native cavity-nesters it had replaced since moving into the area. Although starlings are too large to usurp smaller nest-holes, such as those required by house wrens and violet-green swallows, they undoubtedly replace American kestrels, ash-throated flycatchers, and white-breasted nuthatches. Those birds are now relegated to the more arid, adjacent pinyon-juniper woodlands.

Also present in large numbers that morning were brown-headed cowbirds, social parasites that lay their eggs in the nests of other, smaller birds. See the introductory chapter, "Parks as Islands," and chapter 31 on Big Bend National Park, for more information on the effects cowbirds have on native songbirds. I couldn't help but wonder which birds were being affected at Dinosaur.

All the while I wandered through the campground, violet-green and cliff swallows and white-throated swifts flew overhead. The violet-greens were nesting on the cottonwoods, utilizing deserted woodpecker holes and various cracks and crevices not already in service by starlings. The cliff swallows were constructing their own nests on the adjacent cliffs. I located several groupings of old mud nests, some broken and unused, and others that had been repaired and appeared to be in use. And I found dozens of the square-tailed cliff swallows fluttering over the muddy shore, just above Split Mountain Campground, gathering mud pellets for nest-building. The swifts nest in crevices high on the steep cliffs.

Black-billed magpies were also present during the morning, but only flying over, as if their interests were focused elsewhere. I imag ined that they would have been more interested if I had been eating lunch. They then would compete with the numerous golden-mantled ground squirrels for snacks and leftovers. Instead, the magpies were mostly involved with nesting on the little island below Split Mountain Campground; several large stick nests were evident in the cottonwoods there.

Several other birds were found that morning in and around the campgrounds: small flocks of Canada geese flew over, honking all the while; six northern pintails flew upriver, circling to gain altitude, and flew off toward the north; a couple pairs of barn swallows were flying around the ranger residence; an Empidonax flycatcher, probably a migrant dusky flycatcher, chipped at me from the shrubbery; a solitary vireo sang its rich two- to six-note whistles; two yellow warblers were singing from the high cottonwood foliage at Green River Campground; and a pair of white-crowned sparrows that had not yet moved to their high-country nesting grounds were searching for seeds at the far end of the campground circle.

Within the canyons themselves, one of the most conspicuous birds, judging from sound rather than sight, is the canyon wren. Its descending and decelerating songs are commonplace, and river runners learn to associate them with the river. Canada geese and common mergansers are the most frequently observed waterfowl in the canyons.

The adjacent pinyon-juniper woodlands contained a few additional birds that were evident from the campgrounds: scrub and pinyon jays, plain titmice, rock wrens, black-throated gray warblers, and house finches. I walked the Red Rock Nature Trail, which starts near the entrance to the Split Mountain Campground, follows a cottonwood-filled arroyo, and then circles a juniper-dominated ridge; the trail provided good looks at all those species. I also found several black-throated sparrows singing from big sagebrush. This little sparrow was earlier called "desert sparrow" because of its affinity for the arid lowlands. Its presence within the sagebrush flats on the Red Rock Nature Trail confirmed the desert-like character of the area.

Another day was spent along the Harpers Corner Scenic Drive, walking the Harper's Corner Trail, and visiting Echo Park.

Common ravens were present along the roadway, apparently searching for road kills from the previous night. We found a dead common poorwill that had not yet been claimed by one of the many scavengers. Brewer's blackbirds were most abundant along the roadway and flying over the adjacent sagebrush flats. Most were already paired and courtship was in full swing. Males were attempting to impress their ladies by pointing their heads skyward, fluttering their drooping wings, spreading their tails, and uttering a series of whistles, squeaks, and trills. The male's coal black body and white eyes apparently appeal to the more somber-colored females. This blackbird often nests in colonies of up to 20 pairs; they build nests on the ground as well as on sagebrush.

Mountain bluebirds, American robins, sage thrashers, western meadowlarks, green-tailed towhees, and vesper and Brewers sparrows were all in full song along the roadsides. We found two golden eagles perched on rocky ridges; one flew off as we approached, but the other stayed and allowed us to look it over from our blind inside the vehicle. It was a marvelous bird with a golden sheen to its bulky head.

The bird of the morning was a sage grouse, walking along the road shoulder, pecking now and then at green buds or insects that we couldn't detect. This grouse is a large bird, more than 2 feet (.6 m) in length, with long, pointed tail feathers, mottled brown plumage, and a black belly. The park birds overwinter on the lower sagebrush flats and move to higher elevations, along the edge of the aspens and conifers, to nest, according to the park's resource specialist, Steve Petersburg. Once on their nesting grounds, groups of males (usually 20 to 70 individuals) occupy display sites called leks, where they show off their finery in an attempt to impress the females. Ehrlich and colleagues described the courtship displays thusly: they "strut and inflate neck sacs until nearly reaching the ground; with tail erect and fanned, rapidly throw head back and wings held rigid and almost touching the ground, and deflate sacs with loud popping." The same leks are used annually and are said to have been used by a hundred or more generations of sage grouse.

At Echo Park Overlook, we frightened a blue grouse that apparently was feeding along the road shoulder. It took flight and soared off into the adjacent forest. Its bluish color and smaller size were obvious in flight. This grouse is not a lekking species; instead, solitary males display on scattered territories to entice their mates. See chapter 7 on Yellowstone for a description of this bird's courtship behavior.

I walked the 2-mile (3.2 km) Harper's Corner Nature Trail through high-elevation pinyon-juniper woodlands, past outstanding views of Steamboat Rock and Echo Park, to a high perch (7,510 ft or 2,289 m) overlooking the Green River. I found a fascinating mixture of woodland and forest birds along the trail. Pinyon-juniper birds included black-chinned hummingbirds, gray flycatchers, scrub jays, mountain bluebirds, black-throated gray warblers, and chipping sparrows. The black-throated gray warblers were singing a song that seemed quite different from those that I heard in the lower woodlands. It took me several minutes to find this attractive black-and-white warbler with a tiny yellow spot in front of each eye to confirm its identity. Its varied songs have been described as a buzzy "weezy weezy weezy weezt-weet." See chapter 14 on Zion for additional information on this little songster.

Several boreal bird species were found: Clark's nutcrackers were flying over the northern slope; mountain chickadees called their hoarse "chick a-dee a-dee a-dee" songs from the Douglas firs; two red-breasted nuthatches called out from the lower slope, toy trumpet-like "nyak nyak nyak" sounds; a pair of Townsend's solitaires flew by, and a moment later I detected their mellow call notes; ruby-crowned kinglets were vigorously singing from the conifers; two or three yellow-rumped warblers were detected by their distinct chips; a red crossbill flew across the sky, calling "chink-chink-chink"; and a lone Cassin's finch serenaded me from the top of a tall conifer.

Echo Park lies at the end of a 13-mile (21 km) secondary road that starts near the Island Park Overlook on the Harper's Corner Scenic Drive. I found almost all of the same bird species there as I did at Split Mountain and Green River campgrounds, with a couple of exceptions. Most obvious of these was the greater number of yellow warblers; they seemed to be singing from every cottonwood and riverside thicket. Their cheerful but rapid songs have been described as "tseet-tseet-tseet sitta-sitta-see" or a musical "wee wee wee witita weet." This little all-yellow bird, with chestnut streaks on the male's breast, goes by a number of other names: "wild canary," "golden warbler," and "summer yellowbird."

I couldn't help but wonder why this warbler was so abundant at Echo Park, after I had found only two individuals in the larger but comparable areas of Split Mountain and Green River campgrounds. The one difference that I could detect was the much greater number of brown-headed cowbirds at the campgrounds. Since cowbirds totally eliminated nesting populations of yellow warblers along the Rio Grande at Big Bend National Park, I wondered if a similar change was occurring at Dinosaur.

But this has not been the case for the endangered peregrine falcon; there has been a exciting about-face for this species in recent years. Peregrine nesting sites have increased from a low of only one active aerie in 1976 to ten in 1992. Petersburg told me that the number could be as high as 14, and that biologists are finding sites as close as 4 to 6 miles (6.4-9.6 km) apart. Peregrine recovery is largely due to a 10-year program to restore birds at pertinent locations in the Rocky Mountains. Many of the birds now being found within the canyons of Dinosaur are non-banded birds, undoubtedly the product of those early efforts. The canyon overlooks are the best places to see this swiftest of all birds, which resides within the park from March through September.

Winter birds of the park include a very different assortment from those that occur at other times. The best indications of the wintering bird life are the annual Christmas Bird Counts. The 1990 Christmas count recorded 1,949 individuals of 34 species. The dozen most numerous of those, in descending order of abundance, included red-winged blackbird, house sparrow, horned lark, European starling, black-billed magpie, Brewer's blackbird, dark-eyed junco, ring-necked pheasant, rosy finches, white-crowned sparrow, American goldfinch, and Canada goose.

In summary, the Dinosaur National Monument checklist of birds includes 209 species, of which 54 are considered full-time residents, 85 occur in summer only, and 11 have been reported only during the winter months. Of the approximately 140 species present during the nesting season, 16 are water birds (waders, waterfowl, coot, and shorebirds), 18 are hawks and owls, and 9 are warblers.

<Birds of Special Interest

Peregrine falcon. Watch for this large falcon with the slate gray back anywhere along the rivers where cliffs provide high, inaccessible nesting sites.

Sage grouse. It is reasonably common along the Harper s Corner Scenic Drive in late winter and spring. Its large size, long tail-feathers, and black belly are its most distinguishing features.

Yellow warbler. This is a little all-yellow warbler at riparian areas along the rivers; males possess chestnut streaks on their bright yellow breasts.

Yellow-breasted chat. The loud shrieks, mews, rattles, and squawks of this large warbler are commonplace along the river. Watch for its colorful display flights over the vegetation.

Northern oriole. Males possess orange, black, and white plumage. Northern orioles are commonplace along the river and are often seen chasing one another about the trees and shrubs.

Lazuli bunting. Its turquoise-colored head, white belly, and chestnut sides help identify the colorful male. It is most numerous in brushy areas in the lowlands.

Brewer's blackbird. Hundreds of these all-black birds reside among the sagebrush in spring and summer. Males possess white eyes, and females are a gray-brown color.

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