Great Basin Naturalist

Volume 41 Number 2 Article 16

6-30-1981

Avifauna of the Mt. Dellenbaugh region, Shivwits Plateau,

John G. Blake University of Illinois, Champaign, Illinois

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Recommended Citation Blake, John G. (1981) "Avifauna of the Mt. Dellenbaugh region, Shivwits Plateau, Arizona," Great Basin Naturalist: Vol. 41 : No. 2 , Article 16. Available at: https://scholarsarchive.byu.edu/gbn/vol41/iss2/16

This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Great Basin Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. AVIFAUNA OF THE MT. DELLENBAUGH REGION, SHIVWITS PLATEAU, ARIZONA'

John G. Blake-

Abstract.— An investigation of the avifauna of Mt. Dellenbaugh, Arizona, and nearby areas on the Shivwits Plateau was conducted during fall 1974 and during spring and summer 1975. A total of 92 species of birds was re- corded, of which 56 were considered resident. Species composition is discussed in relation to habitat.

From an ornithological standpoint, the National Recreation Area. The northern Shivwits Plateau in northwestern Arizona has boundary of the recreation area crosses the been neglected. In fact, bird studies in the southern edge of the Shivwits Plateau, close entire region (northwestern Arizona, south- to Mt. Dellenbaugh. As a consequence, sever- western Utah, and adjoining parts of south- al trips were made to the Shivwits Plateau by eastern Nevada) have been limited. The need members of the NPS study team, with obser- for work in this part of Arizona is evident vations taken on occurrence and distribution from an examination of distribution maps in of flora and fauna. The present paper pres- Birds of Arizona (Phillips et al. 1964) and is ents an account of bird species observed. Dis- further emphasized by Monson and Phillips tribution of birds within different habitats is (1964:178). Despite this lack of information, discussed. virtually no work has been conducted on the Place names and topographical informa- Shivwits Plateau and nearby areas. tion used in the present report are taken Mt. Trumbull, located approximately 50 from U.S.G.S. 1:250,000 topographical maps. km NE of Mt. Dellenbaugh on the Uinkaret Plateau, was visited for by Huey (1939) ap- Study Area proximately two weeks in late July; Mt. Trumbull is the closest reported study area to The Shivwits Plateau is primarily flat ta- that part of the Shivwits Plateau covered by bleland, with occasional lava-capped buttes the present report. Farther east, Rasmussen and isolated mountains. Over much of the (1941) and Jenks (1931) have reported on bird southern part of the plateau elevation is ap- communities of the . In- proximately 1830 m. Northward, the plateau vestigations on avifauna of south central and stretches toward Utah, gradually decreasing southwestern Utah have been somewhat in elevation. The southern boundary is more extensive (Presnall 1935, Hardy and marked by an abrupt descent to the Sanup

Wiggins 1940, Behle 1943, Behle et al. 1958, Plateau, at 1370 m. Numerous steep-walled Wauer and Carter 1965) but have not includ- canyons dissect the plateau, leading eventu- ed the Shivwits Plateau region. Farther west, ally to the . Mt. Dellenbaugh, several authors have examined the desert avi- the highest peak in the southern part of the fauna of the Virgin River Valley in Nevada, plateau, reaches an elevation of 2130 m. Ap-

Arizona, and Utah (Tanner 1927, Wauer and proximately 8 km NE is Yellow John Moun- Russell 1967, Wauer 1969, Behle 1976, Whit- tain, which reaches an elevation of 2060 m more 1977). (Fig. 1). In 1975, a study was initiated by the U.S. Observations are primarily from the vicin- National Park Service Cooperative Resources ity of Mt. Dellenbaugh and Green Springs Studies Unit located at the University of Ne- Canyon; additional observations were made vada, Las Vegas, to document distribution of on a trip along Twin Point (Fig. 1). Various plants and animals within the distinct habitats occur at different locations

'This work was supported by NPS/UNLV Contracts 8000-4-0031 /CX 8000-6-0034. 'Department of Ecology, Ethology, and Evolution, Vivarium Building, University of Illinois, Champaign, Illinois 61820.

259 260 Great Basin Naturalist Vol. 41, No. 2

UTAH

NM

T13'45

36''15

36°00

Fig. 1. The southern part of the Shivwits Plateau is shown, with sites mentioned in the report indicated. Location of the plateau within Arizona is shown in the upper right. June 1981 Blake: Arizona Birds 261 and are briefly described below. Plant identi- others are bordered by relatively dense stands flcation was by members of the NPS study of shrubs, particularly rabbit brush. team. All habitat types described above occur at Predominant vegetation over most of the or near Mt. Dellenbaugh. A large sagebrush

Shivwits Plateau is pinyon pine {Pinus mono- field occurs just north of the mountain and phyla) - juniper {Juniperus osteosperma) has been maintained in part for use as a land- woodland. Understory is sparse within this ing strip. Cattle also graze over parts of the open, relatively xeric woodland, consisting field; several ponds occur in or around the primarily of sagebrush {Artemisia) and scrub perimeter of the field. Pinyon-juniper wood- of the mountain ex- oak {Quercus). Locally concentrated patches land surrounds much and tends south to the plateau edge. Pinyon- of oaks and sagebrush produce a more brushy juniper extends part way up the slopes of the appearance in certain areas (e.g., southern mountain, particularly on the northern face. end of Twin Point). Ponderosa pine occurs in belts near the base Ponderosa pine {Pinus ponderosa) occurs in of the mountain, bordering the sagebrush at limited amounts, principally along drainages numerous points. Mixed oak scrub pre- where soils are deeper and moisture condi- dominates over much of the mountain slope. tions higher. Scattered individuals occur Green Springs Canyon is located approx- throughout the area. Due to drainage pat- imately 6 km ESE of Mt. Dellenbaugh (Fig. terns, ponderosas occur primarily as belts in- 1). Pinyon-juniper woodland predominates terspersed in pinyon-juniper woodland and over much of the surrounding plateau. An bordering open sagebrush fields. Understory open ponderosa pine stand occurs at the head and ground cover are sparse, with a mixed of the canyon. The stand was logged at some shrub assemblage that includes species of oak, time in the past, and presently is composed sagebrush, mountain mahogany {Cercocarpiis of large, widely spaced trees, forming a more montanus), and others. parklike appearance than is found elsewhere. Upper slopes of Mt. Dellenbaugh and Patches of sagebrush occur at scattered loca- edges and slopes of various canyons are cov- tions, but large expanses are absent from the ered with a mixed assemblage of relatively area. Canyon slopes and edges are covered bmshy shrubs and trees, which produces a by oak scrub, with Gambel oak particularly chaparral type habitat. Although oaks, in- prevalent in patches on midslopes. The can- cluding scrub oak {Quercus turbinella), Gam- yon bottom is quite moist and supports a lim- vegetation. bel oak {Q. gambelii), and wavyleaf oak {Q. ited amount of riparian undulata), are particularly abundant, numer- Twin Point is predominantly pinyon- the ous other shrubs also occur, including moun- juniper woodland with oak scrub along of the tain mahogany and manzanita {Arctosta- plateau rim and at the southern end sagebrush fields occur at several phylos piingens). Particularly on the slopes of point. Large plateau. Mt. Dellenbaugh, New Mexican locust {Rob- locations along the inia neomexicana) occurs in locally dense stands. Methods Large expanses of sagebrush {Artemisia tri- dentata) occur at a number of locations on Mt. Dellenbaugh was visited in fall 1974 the plateau. In a number of instances, juniper (28 September, 4-5, 12-14 October), and trees have been cleared, and large piles of spring (17-18 May) and summer (7,9,27-29 dead trees add a significant component to the June) 1975. Green Springs Canyon was vis- habitat. Additional plant species occurring ited 28-29 September 1974 and 16 May and with sagebrush include rabbit brvish {Chryso- 6,8 June 1975. A trip was made to the south- thamnus spp.), snake weed {Gutierrezia mi- ern end of Twin Point 6-7 October 1974; the crocephala), and others. northern end was briefly visited again on 7 Several ranchers graze cattle on the June 1975. Thus, a total of 19 days was spent plateau, and a number of ponds have been in field observations. dur- constructed to supply water. Vegetation is No regular censuses were conducted virtually absent around some ponds, but ing the study, but all habitats were surveyed 262 Great Basin Naturalist Vol. 41, No. 2 on a regular basis. Observations were con- trips, but seen in large numbers on each trips, ducted on foot and were concentrated in the were designated as common. This method is morning, from approximately one-half hour subjective, but with criteria consistently ap- prior to sunrise until approximately 4-5 plied does provide an index of abundance. hours after sunrise. Additional observations were made throughout the day with a second Results concentrated effort in the evening. During observation periods, a count was kept of the A total of 92 species was recorded during number of individuals of each species seen. visits to the Shivwits Plateau (Appendix). Of The trip out from Twin Point involved peri- these, 13 were observed only in 1976, includ- odic stops for observation as well as observa- ing one summer resident (Poor-will), 3 mi- tions from the vehicle. grants, and 9 visitors. The failure to record Several additional trips were made to the additional summer residents suggests that Mt. Dellenbaugh area in spring and summer coverage in 1975 was relatively complete. 1976 by other members of the study team. The following discussions that involve habitat Observed species new to the area are listed at preference will not include these species, due the end of the Appendix. to a lack of personal observations. Species were classified as resident (includ- Of the total observed, 56 species were con- ing those thought to be permanently resident sidered probable breeding residents, 24 were on the plateau and those that breed in the migrants, and 12 were visitors. More species area but depart for winter), migrant (those were observed in pinyon-juniper woodland passing through the area in fall and/ or spring than in other habitats (Table 1), although the as part of a regular migration), and visitors numbers in oak sciiib and ponderosa pine (including those that breed elsewhere, fre- were comparable. Among residents, a greater quently at lower elevations, which appear on number were recorded from oak scrub habi- the Shivwits Plateau irregularly but not dur- tat (35) than from pinyon-juniper (34) or pon- ing normal migration periods). Most visitors derosa pine (31). Migrants were considerably were observed only once. more common in pinyon-juniper and pon- Relative abundance designations were de- derosa pine stands than in oak scrub. The termined from the number of days on which number of resident species observed on fields the species was observed, together with the or at ponds were similar (Table 1). Heavy use number of individuals observed. Abundant of ponds by migrants (29 percent of the total species were designated as those seen on ap- observed at ponds) resulted in a higher spe- proximately 80 percent or more of trips, cies total from ponds than from fields. common species were observed 60-80 per- Thirty-two species were observed in only cent of the time, uncommon species were ob- one habitat (Table 2). Of these, 15 were resi- served 40-60 percent of the time, and rare dent, 14 were migrant, and 3 were visitors. species were observed less than 40 percent of Only a single resident species (Black-throated the time. The number of individuals observed Gray Warbler) was restricted to pinyon- was used to modify these categories. Thus, a juniper woodland, although this habitat is species seen on all trips, but with only 1-2 in- predominant over the plateau. More species, dividuals recorded each time was designated 5, were restricted to oak scrub habitat than common. Alternatively, species seen on few to any other habitat. More than twice as

Table 1. Distribution within habitats is shown for species recorded at or near Mt. Dellenbaugh, Arizona, 1974-1975. June 1981 Blake: Arizona Birds 26a many migrants were observed only at ponds resident species total from Mt. Dellenbaugh

(7) than in any other habitat (3 in pinyon- (56 species). In addition, Mt. Trumbull reach- jmiiper). In contrast to residents, only one mi- es a higher elevation (2447 m) than Mt. Del- grant was restricted to oak scrub areas. Vis- lenbaugh, accounting in part for some of the itors also were slightly more frequent at species differences between the two areas. ponds than in other habitats. The present report presents a preliminary species list, but considerable additional work

in the area is needed. Bird communities on Discussion the more isolated Sanup Plateau have, for ex- Close proximity of several distinct habitat ample, not been investigated at all. Addition- types may influence the species composition ally, although pinyon-juniper woodland of an area. Habitat variability is greater at forms a fairly continuous cover over the Mt. Dellenbaugh than at Green Springs Can- plateau, additional habitat types are present yon, and a greater number of species were as more or less isolated patches of varying resident at Mt. Dellenbaugh (51) than at the size. An examination of bird use of these hab- latter area (33). Four species, including 3 itat patches, with respect to area and degree owls, were recorded only from Green Springs of isolation, would prove interesting. Canyon. In addition, Canyon Wrens were the canyon slopes at Green present along Acknowledgments Springs. Presence of large sagebrush fields and several cattle ponds accounted for 4 of I would like to thank G. T. Austin for addi- Del- 15 species recorded only from Mt. for plant tional bird records and J. Holland (Killdeer, Nighthawk, lenbaugh Common identifications. Horned Lark, Mountain Bluebird); Turkey Vultures and Red-tailed Hawks also were seen more frequently over fields or at ponds. Literature Cited Species composition at Mt. Dellenbaugh Behle, W. H. 1943. Birds of Pine Valley Mountain re- similar that re- and surrounding areas was to gion, southwestern Utah. Univ. Utah Bull. 34, ported by Huey (1939) for Mt. Trumbull. Of Biol. Sen 7:1-85. 51 species included by Huey in his report, 43 1976. Mohave Desert avifauna in the Virgin Riv- Utah, Nevada, and Arizona. Condor were from the Mt. Trumbull region, with 8 er Valley of 78:40-48. from areas farther north. Of the 43, 38 were B. and C. M. Greenhalgh. Behle, W. H., J. Bushman, considered resident at Mt. Tnimbull, with 3 1958. Birds of the Kanab area and adjacent high more possibly resident in the area. Of the 43 plateaus of southern Utah. Univ. Utah Biol. Ser. birds seen at Mt. Tnunbull, 32 were consid- 11:1-92. Hardy, R., and H. G. Higgins. 1940. An annotated ered resident at Mt. Dellenbaugh, 5 were not checklist of the birds of Washington County, considered resident, and 6 were not observed Utah. Proc. Utah Acad. Sci., Arts, Lett. at Mt. Dellenbaugh. Seven of the 8 species 17:95-111. recorded by Huey (1939) from areas north of Huey, L. M. 1939. Birds of the Mount Trumbull region, Arizona. Auk 56:320-325. Mt. Trumbull were seen at Mt. Dellenbaugh; Jenks, R. 1931. Some birds and their nests on the Kai- 4 were considered resident. The present re- bab. Nature Notes 5:101-105. port covers a greater area than did Huey MoNsoN, G., AND A. R. Phillips. 1964. An annotated (1939), which accounts in part for the higher checklist of the species of birds in Arizona. Pages

Ari- Table 2. Distribution of species restricted to one habitat. Species were observed at or near Mt. Dellenbaugh, zona, 1974-1975. 264 Great Basin Naturalist Vol. 41, No. 2

175-248 in C. H. Lowe, ed.. The vertebrates of Wauer, R. H. 1967. Recent bird records from the Virgin Arizona. Univ. of Arizona Press, Tucson. River Valley of Utah, Arizona, and Nevada. Con-

R., and G. Monson. 1964. dor 71:331-.335. Phillips, A. J. Marshall, Wauer, R. H., and D. L. Carter. 1965. Birds of Zion The birds of Arizona. Univ. of Arizona Press, National Park and vicinity. Zion Nat. Hist. As- Tucson. soc, Springdale, Utah. Presnall, C. C. 1935. The birds of Zion National Park. Wauer, R. H., and R. C. Russell. 1967. New and addi- Proc. Utah Acad. Sci., Arts, Lett. 12:197-210. tional birds in the Virgin River Vallev. Condor Rasmussen, D. I. 1941. Biotic communities of Kaibab 69:420-432. Plateau, Arizona. Ecol. Monogr. 11:231-275. Whitmore, R. C. 1977. Habitat partitioning in a com- Tanner, V. M. 1927. Notes on birds collected in the Vir- munity of passerine birds. Wilson Bull. gin River Valley of Utah. Condor 29:196-200. 89:25.3-265.

Appendix

Species observed on Shivwits Plateau, Arizona. Observations were made at Mt. Del- lenbaugh (MD), Green Springs Canyon (GS), and Twin Point (TP). Residential status (R) is noted (M = migrant, V = visitor, PR and SR = permanent and summer residents, respec- tively). Relative abundances are indicated by season (F = fall, SP = spring, SU = summer). Five habitats are distinguished (PJ = pinyon-juniper woodland, PP = ponderosa pine, OS / oak scrub, F = sagebrush fields, P = ponds). Nomenclature follows AOU Check-list of North American Birds, 1957 ed., with 32nd and 33rd supplements.

Abundance Location Habitat

Species R SP SU MD GS TP PJ PP OS F Green-winged Teal M X + Anas crecca Ruddy Duck M + Oxyura jamaicensis Turkey Vulture SR U C + + + Cathartes aura Sharp-shinned Hawk SR U U + + + + Accipiter striatus

Cooper's Hawk M U + -I- + + + + Accipiter cooperi Red-tailed Hawk PR U R U Buteo jamaicensis

Golden Eagle PR X -I- + Aqtiila chrysaetos

American Kestrel SR U U C -I- -I- + + + Falco sparverius

Killdeer SR -I- + Charadrius vociferus Spotted Sandpiper M X + Actitis macularia Long-billed Dowitcher M X + Limnodroniiis scolopaceus Black-necked Stilt M X + Himantopus nxexicanus Bonaparte's Gull M X + + Larus Philadelphia Band-tailed Pigeon SR + + + + + Columba fasciata June 1981 266 June 1981 Blake: Arizona Birds 267

Appendix continued. 268 Great Basin Naturalist Vol. 41, No. 2

Appendix continued.