Monographs in Field Ornithology 3:29-63, 2001

STATUS AND TAXONOMY OF THE COLORADO DESERT AVIFAUNA OF BAJA CALIFORNIA

Michael A. Patten*, Eric Mellink✣, Héctor Gómez de Silva**, and Thomas E. Wurster✣✣

* San Diego Natural History Museum, Box 121390, San Diego, California 92112, USA ✣ Centro de Investigación Científica y de Educación Superior de Ensenada, Apartado Postal 2732, Ensenada, B.C., México ** Instituto de Ecología, Universidad Nacional Autónoma de México, Apartado Postal 70-275, C.P. 04510, México, D.F., México ✣✣ 278 Santa Anita Court, Sierra Madre, California 91024, USA

ABSTRACT RESUMÉN

The western Sonoran Desert, the Colorado Desert, El Desierto Sonorense Occidental, el Desierto del extends into the northeastern portion of the Baja Colorado, se extiende y penetra en la porción California Peninsula, encompassing the floodplain nororiental de la Península de Baja California, of the lower Río Colorado, a part of the Salton Sink, englobando las planicies inundables cerca de la and the northwesternmost Gulf of California The desembocadura del Río Colorado, una parte de la avifauna of this arid, hot region has not been studied Cuenca del Salton, y la parte mas noroccidental del extensively but, as expected, it appears to be most Golfo de California. La avifauna de esta árida, similar to that of the Salton Sea region, southwest- calurosa región no se ha estudiado extensivamente ern Arizona, and western Sonora. Herein we have pero, como se esperaría, ésta parece ser muy similar compiled available data on species and subspecies a la de la región del Mar del Salton, suroccidente de occurring in the region to elucidate patterns of oc- Arizona, y occidente de Sonora. Aquí hemos currence and relative abundance compared to these compilado información disponible sobre especies y adjacent regions, and to set the groundwork for fu- subespecies que ocurren en la región para elucidar ture work in the area. We provide status and refer- patrones de ocurrencia y abundancia relativa ences, including many previously unpublished sight comparados con estas regiones adyacentes, y records, for all avian taxa reliably recorded in the re- establecer el trabajo base para trabajos futuros en el gion (280 native species and an additional 56 sub- área. Proporcionamos el status y las referencias, species). We also list species likely to occur, on the incluyendo varios registros de observaciones no basis of their status in adjacent regions, but not yet publicados previamente, para todos los taxa con recorded in the Colorado Desert of Baja California registros fidedignos en la región (280 especies (26 species), and we have specifically addressed nativas y 56 subespecies adicionales). Tambén and debunked several species claimed for the re- enlistamos a especies que probablemente ocurren, gion. con base en su status en regiones adyacentes, pero que no han sido aún consignados para el Desierto del Colorado de Baja California (26 especies), y hemos analizado específicamente y descartado varias especies consignadas para la región.

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The Baja California Peninsula has a long history of to paint a more or less complete, albeit provisional, ornithological exploration, although early ornitho- portrait of the birdlife of this intriguing region. logical exploration was distinctly concentrated on Were it not for recent detailed avifaunal works for the northwest coast, in the northern peninsular neighboring regions, namely the lower Colorado ranges (the Sierra Juárez and Sierra San Pedro River valley (Rosenberg et al. 1991), Sonora (Rus- Mártir), and in the Cape District. Extensive collect- sell and Monson 1998), and the Salton Sink (Patten ing and field study through the 1920s culminated in et al. in press ), such an effort might still be seriously publication of Grinnell’s (1928) important tome, wanting. still the most comprehensive review of the penin- sula’s avifauna. Extensive work since has focused Heavy reliance on these works will inherently lead on these same regions, with increasing attention to to a few errors of commission, but the benefits far coastal wetlands (Massey and Palacios 1994), the outweigh the costs of serious errors of omission Vizcaíno Peninsula, Isla Guadalupe, and the south- from northeastern Baja California evident in both ern Gulf of California (Wilbur 1987, Erickson et al. Grinnell (1928) and, especially, Wilbur (1987; see 2001). Everett 1988). Although we attribute no species to the Colorado Desert avifauna of Baja California that One region of the Baja California Peninsula, the has not been recorded definitely, we often infer sta- low-lying northeastern Colorado Desert and Río tus of species in this region from neighboring re- Colorado delta, has received decidedly little atten- gions with significantly more data; wild organisms tion by comparison, despite its strikingly distinct ignore political boundaries. To that end, we present birdlife and biogeography (Nelson 1922, Bancroft an annotated checklist for the avifauna of northeast- 1926). There were notable, but uneven, early efforts ern Baja California that is both complete and accu- in the Río Colorado delta and associated Gulf of rate to the extent possible. We hope this effort California (Stone and Rhoads 1905, Murphy 1917, contributes to an increased appreciation for, and Huey 1927) and data remain limited, so a thorough study of, this region, such that we can one day paint description of the region’s avifauna remains impos- that complete portrait. sible. Yet there are enough historical and recent data

TOPOGRAPHY AND BIOGEOGRAPHY

As defined herein, northeastern Baja California is Biotically and climatically, this region is the south- an inverted triangle including the whole of Colo- western limit of the Colorado Desert floristic prov- rado Desert area bounded to the north by the United ince (Figure 3-2; Nelson 1922, cf. Bancroft 1926). States border, to the east by the Río Colorado, and to The region is characterized by low rainfall, most of the west by the base of the eastern escarpment of the which occurs during monsoonal flows northward peninsular ranges, specifically the Sierra Juárez, Si- through the Gulf of California during summer erra las Pintas, Sierra Tinaja, and Sierra de San months (Turner et al. 1995, Patten and Minnich Felipe (Figure 3-1; see Nelson 1922). The southern 1997). Aside from the eastern escarpment of the end of Bahía de San Felipe (±31°N latitude), at peninsular ranges and the Sierra Cucapah and Sierra Punta Radar, establishes the southern tip of the tri- Mayor, which separate the Mexicali Valley from angle. Only a modest amount of waters in the Gulf Laguna Salada, the area is below, at, or only slightly of California are included, inward from a line be- above sea level (Nelson 1922). Therefore, the re- tween Rocas Consag (off San Felipe) and the east gion considered herein lies below ±150 m elevation side of Isla Montague. and generally below 50 m. Indeed, save for various mountains and for sandy benches lying between the Río Colorado and Mexicali Valley (e.g., Mesa 31

Andrade), much of the northern portion of this re- P. pubescens, Catclaw Acacia greggi, Ocotillo gion lies within the lakebed of historical Lake Fouquieria splendens, and, in washes, Blue Palo Cahuilla and much of the southern portion lies Verde Cercidium floridanum (Nelson 1922, Turner within the Río Colorado floodplain. et al. 1995). Atypical of most deserts of southwest- ern North America, cacti are poorly represented, The majority of the Mexicali Valley is now under with most species being small (e.g., Echinocereus extensive agriculture, with isolated ranches sup- spp., Mammillaria spp.) and occurring on slopes of porting patches of trees ranging from Fremont Cot- the eastern escarpment of the Peninsular Ranges, tonwood Populus fremontii (some probably though there are stands of Senote Cereus schottii remnant natives) and Eucalyptus spp. to Athel just north of San Felipe. Vegetation transitions to Tamarix aphylla, Saltcedar T. ramosissima,and species characteristic of the Vizcaíno Desert (e.g., Myoporum spp. Both the Río Colorado and Río Red Elephant Tree Bursera hindsiana, Cordón Hardy formerly supported extensive gallery ripar- Pachycereus pringlei) at the southern edge of Bahía ian forest dominated by cottonwood, Black Willow de San Felipe at Punta Radar (Figure 3-2). Exten- Salix gooddingii, and Arrowweed Pluchea sericea sive mudlfats and alkaline flats surround the north- (Figure 3-3; Murphy 1917, Nelson 1922). Large ern edge of the Gulf of California, the latter stands of riparian forest remain along the Río Colo- covering Laguna Salada and Salinas Ometepec. rado between Algodones and Mezquital, but most Floodplain habitat was formerly extensive (Figure has been cleared or has been overtaken by non-na- 3-5), though seasonal flooding persists (Figure 3-6). tive Saltcedar (Figure 3-4). Characteristic vegeta- Vegetation is sparse in these areas, generally noth- tion in undisturbed desert is Creosote Larrea ing more than a low cover of saltgrass Distichlis tridentata, Brittlebush Encelia farinosa, Quailbush spp. and/or pickleweed Salicornia spp. Atriplex lentiformes, Spiny Saltbush A. polycarpa, Honey Mesquite Prosopis glandulosa, Screwbean

ANNOTATED LIST OF THE BIRDS

Accounts are synthetic rather than exhaustive, with Salton Sea, lower Colorado River, and northwestern a summary statement about status rather than a list Sonora. Many additional species have been re- of all known records. The list is arranged in a phylo- corded in adjacent regions as casual vagrants (e.g., genetic sequence and using species-level taxonomy Common Black-Hawk Buteogallus anthracinus, and nomenclature following the latest edition of the Northern Jacana Jacana spinosa); they too could American Ornithologists’ Union’s Check-list of reach northeastern Baja California, but are not in- North American Birds (A.O.U. 1998) plus its most cluded herein because we cannot predict all va- recent supplements. An alternate taxonomic treat- grants that may occur. ment is offered when we differ from the A.O.U. treatment. When only one subspecies is known Status presented for each species is based on numer- from the region, the trinomial is provided directly ous sources. Important early publications (Murphy following the common name. If multiple subspe- 1917, Nelson 1922, Bancroft 1927, Huey 1927, cies are known or expected, the status of each is ab- Grinnell 1928) formed the baseline, as did extensive stracted in the account. We do not list taxonomic museum holdings. Standard abbreviations for mu- authorities; they may be found in A.O.U. (1957, seum collections are AMNH = American Museum 1998), Gibson and Kessel (1997), and Patten et al. of Natural History, New York; ANSP = Academy of (in press). Species listed in brackets are not sup- Natural Sciences, Philadelphia; FMNH = Field Mu- ported by definite records for northeastern Baja Cal- seum of Natural History, Chicago; LACM = Natural ifornia but might be reasonably expected to occur in History Museum of Los Angeles County, Los An- the region based on inferences from records for the geles; MVZ = Museum of Vertebrate Zoology, Uni- 32 versity of California, Berkeley; SDNHM = San and statements about status, distribution, and taxon- Diego Natural History Museum, San Diego; UABC omy (including synonymy) for the Salton Sea and = Universidad Autónoma de Baja California, Imperial Valley of southeastern California are from Ensenada; UCLA = Dickey Collection, University a forthcoming book on the avifauna of that region by of California, Los Angeles; UMMZ = University of Michael A. Patten, Guy McCaskie, and Philip Unitt Michigan Museum of Zoology, Ann Arbor; USNM (Patten et al. in press). = National Museum of Natural History, Smithso- nian Institution, Washington, D.C.; WFVZ = West- Status designations for each species are conven- ern Foundation of Vertebrate Zoology, Camarillo, tional. Common refers to a species that is encoun- California. Recent data are from Wilbur (1987), tered frequently and/or in large numbers. Fairly published short papers pertaining to the region (e.g., common refers to a species that is encountered rou- Howell and Webb 1992, Palacios and Mellink 1992, tinely in modest numbers. Uncommon refers to a Patten et al. 1993, Ruiz-C. and Rodríguez-M. species encountered infrequently and in small num- 1997), and unpublished field notes from ourselves bers. Rare refers to a species encountered only on and various other field ornithologists (see Acknowl- occasion (e.g., extremely small numbers annually edgments). Observers are listed, by their initials, for or less), but with a sufficient number of records to all previously unpublished sight records, whether suggest that the region lies within its regular range personally communicated or relayed to us by others; (albeit perhaps on the periphery). Casual refers to a they are: E.N. Anderson, L.R. Bevier, R.A. species that has been recorded on one to several oc- Erickson, M. Force, K.L. Garrett, H. Gómez de casions; vagrant is used when the region lies outside Silva, R.A. Hamilton, O. Hinojosa-Huerta, S.N.G. the normal range of the species, but visitor is used if Howell, D. Kelly, C.C. Lamb, E. Mellink, K.C. the region lies within its normal range. Seasonal Molina, E. Palacios, R. Palmer, M.A. Patten, P. designations mostly reflect what the birds are doing Pyle, C. Radamaker, K.A. Radamaker, R.A. and thus are not human-defined seasons per se. Rowlett, A.M. Sada, D.E. Schmoldt, B.D. Smith, S. Thus, a Black-chinned Hummingbird (scientific Webb, R.E. Webster, and T.E. Wurster. names are in the list below) in March is a spring transient, but a White-crowned Sparrow then is still Most recent fieldwork has been rather haphazard in wintering and a Le Conte’s Thrasher is likely fledg- geographic coverage, but with regular surveys con- ing young. Separate statements about migration ducted at Campo Geotérmico Cerro Prieto (Molina and wintering/summering are used only for species and Garrett 2001), around Isla Montague (Palacios with a substantial migrant presence (e.g., Western and Mellink 1992, 1993, Peresbarbosa and Mellink Sandpiper) in addition to wintering/summering. 1994, Mellink et al. 1997), and in the Sierra las Pintas (H. Gómez de Silva). When limited records For the record, claims of the Yellow-crowned support a numerical and/or seasonal status consis- Night-Heron Nyctanassa violacea, California Con- tent with the Imperial Valley and lower Colorado dor Gymnogyps californianus, Broad-winged River Valleys, we extrapolated from those valleys Hawk Buteo platypterus, Golden Eagle Aquila with little comment. We have drawn attention to all chrysaetos, Winter Wren Troglodytes troglodytes, cases where a species’ status was mainly extrapo- andGrayCatbirdDumetella carolinensis by lated from adjacent regions rather than based on di- Rhoads (Stone and Rhoads 1905, Murphy 1917) are rect data from Baja California. Rather than considered invalid and are disregarded (see Grinnell Anglicized names, locality names follow standard 1906, 1918). Excepting the condor, all have been usage in Mexico (with the exception of “Mexicali recorded on the lower Colorado River (Rosenberg Valley”instead of “Vallede Mexicali”). In this vein, et al. 1991) and/or around the Salton Sea, but with “Colorado River” consistently refers to the United precious few records of each despite substantially States portion of the river, whereas “Río Colorado” greater coverage. We also omit claims of infrequent refers to the Mexico portion. All uncredited records occurrence of Barrow’s Goldeneye Bucephala 33 islandica at the Río Colorado delta (Kramer and Ducks Nomonyx dominicus breeding and wintering Migoya 1989). This species winters regularly on in northeastern Baja California (Kramer and the lower Colorado River, but with only three re- Migoya 1989) are baseless and herein ignored. A cords south of Parker, Arizona (Rosenberg et al. few additional species claimed in the region without 1991); there are only six records for the Salton Sea. sufficient documentation, but which might occur, It is unknown farther south and has not been re- are treated in the species accounts in brackets. corded reliably in Mexico. Claims of Black-bellied Whistling-Ducks Dendrocygna autumnalis, Muscovy Ducks Cairina moschata, and Masked

GAVIIFORMES Horned Grebe Podiceps auritus. Rare winter visi- tor (November–April) on Gulf of California. This Gaviidae species is generally treated as monotypic, with P. a. Red-throated Loon Gavia stellata. Rare spring cornutus not diagnosable (Mayr and Cottrell 1979). transient (April) on Gulf of California (Huey 1927, REW); rare in winter (Devillers et al. 2001; two at Eared Grebe Podiceps nigricollis californicus. San Felipe 15 January 1989 TEW). Common winter visitor to Gulf of California (No- vember–March); uncommon through summer as a Pacific Loon Gavia pacifica. Fairly common win- non-breeder; e.g., alternate-plumaged bird at Cam- ter visitor (November–April) on Gulf of California; po Geotérmico Cerro Prieto 4 June 1998 (EM et al.). numbers larger in spring (e.g., 1200 in San Felipe area 29 March 1985; REW). One summer record, Western Grebe Aechmophorus occidentalis from San Felipe 22 August 1992 (KAR, TEW). occidentalis. Uncommon to irregularly fairly com- mon breeding resident; e.g., up to 300 birds with Common Loon Gavia immer. Fairly common mi- ±20 young at south end of Laguna Salada 20 grant in spring (April–May) and fall (late Septem- March–23 April 1984 (REW). Aechmophorus of ber–November), with a high count of a remarkable unknown species were reported summering at Vol- 1500 birds during fall (Mellink et al. 1997). Un- cano Lake 11 June 1918 (Oberholser 1919), sug- common winter visitor (late September–mid-April) gesting potential breeding for some time. to Gulf of California. Two summer records, from Volcano Lake on unspecified summer date Clark’s Grebe Aechmophorus clarkii (Friedmann et al. 1950) and Campo Geotérmico transitionalis. Uncommon resident; probably Cerro Prieto 1 September 2000 (SNGH et al.). breeds around Río Colorado delta and Mexicali Val- ley. In general outnumbers its congener on Salton Yellow-billed Loon Gavia adamsii. Casual sum- Sea by ratios of 2:1 or 3:1. However, mer vagrant. One in basic plumage at Campo El Aechmophorus species are of near equal abundance Paraiso 30 June 1973 (Simon and Simon 1974), im- in Imperial Valley and the Western predominates in pugned by Phillips (1990), represents one of three northeastern Baja California; e.g., of ±300 Mexico records, all from Baja California. Aechmophorus (including five young) at Laguna Salada 28 March 1985 only 15% were Clark’s PODICIPEDIFORMES (REW), a ±5:1 ratio in favor of Western. On Gulf of Podicipedidae California, ratio is even higher in favor of Western (KLG, MAP). Pied-billed Grebe Podilymbus podiceps podiceps. Fairly common breeding resident. 34

PROCELLARIIFORMES ary 1940 (LACM 50463–50470)—but most dis- Diomedeidae perse away from gulf in winter. Laysan Albatross Phoebastria immutabilis. Rare Least Storm-Petrel Oceanodroma microsoma. spring (May) visitor to head of Gulf of California Common breeder in Gulf of California; most often (Newcomer and Silber 1989). A few have moved reported April–October. Breeds or formerly bred northward through Salton Sea region (Patten and on Rocas Consag (Bancroft 1927). Minnich 1997). PELECANIFORMES Procellariidae Phaethontidae [Cook’s Petrel Pterodroma cookii]. Four or five Red-billed Tropicbird Phaethon aethereus records for Salton Sea (Patten and Minnich 1997), mesonauta. Although not attributed to Rocas all from July, of birds that presumably moved north Consag by Wilbur (1987), a pair was taken there 12 from Gulf of California, but no records for north- April 1925 (Bancroft 1927, UCLA 15092, 15097) eastern Baja California. Species is monotypic, P. c. and an adult photographed there 20 February 1995 orientalis being a synonym (Mayr and Cottrell (KAR; Figure 3-7). Otherwise rarely noted in 1979). northern Gulf of California, although recorded even at mouth of Río Colorado, 25 April 1925 (van Pink-footed Shearwater Puffinus creatopus. Rossem and Hachisuka 1937) and breeds off Sonora Fairly common summer visitor (May–October) to (Mellink and Palacios 1993). northern Gulf of California (Wilbur 1987, RAR). This species and next two occur almost strictly well Sulidae offshore. [Masked Booby Sula dactylatra personata]. A Sooty Shearwater Puffinus griseus. Common vis- subadult reported east of Rocas Consag 23 Septem- itor to northern Gulf of California, mainly in sum- ber 1997 (RAR, MF) was just outside the region mer (April–October). covered herein. Otherwise unknown in northern Gulf of California. S. d. californica is a synonym Black-vented Shearwater Puffinus opisthomelas. (Pitman and Jehl 1998). Uncommon summer visitor (March–September) to northern Gulf of California, sometimes occurring Blue-footed Booby Sula nebouxii nebouxii. Irreg- later in the season (e.g., December at El Golfo de ularly fairly common perennial visitor, but mainly a Santa Clara, Sonora; KLG). post-breeding dispersant (July–November) to northern Gulf of California and associated Río Col- Hydrobatidae orado delta. May be common in El Niño years; e.g., Leach’s Storm-Petrel Oceanodroma leucorhoa a few thousand on Rocas Consag 19 August 1998 subsp.? Rare summer (June–September) visitor to (EM). northern Gulf of California (RAR). Many individu- Brown Booby Sula leucogaster brewsteri. Irregu- als are dark-rumped, but may be either nominate larly fairly common perennial visitor, but mainly a subspecies, which has many synonyms (Ainley post-breeding dispersant (July–December) to 1980, Unitt 1984), or O. l. socorroensis. northern Gulf of California and Río Colorado delta Black Storm-Petrel Oceanodroma melania. (Mellink et al. 1997), occasionally in large numbers Common breeder in Gulf of California; most often to former (Dunning 1988). Some linger into winter; reported April–October. Breeds or formerly bred e.g., 12 at San Felipe 15 January 1989 (TEW), 10 at on Rocas Consag off San Felipe (Bancroft 1927). San Felipe 22 February 1998 (RAE). Breeds on Perhaps resident in gulf (Wilbur 1987)—e.g., a se- Rocas Consag (Bancroft 1927), where various spec- ries of eight specimens from Rocas Consag 31 Janu- imens taken; e.g., two adults 31 January 1940 35

(LACM 50471, 50472) and two juveniles 12 April CICONIIFORMES 1925 (UCLA 15098, 15099). Ardeidae Pelecanidae American Bittern Botaurus lentiginosus.Un- American White Pelican Pelecanus common to rare winter visitor (late August–April). erythrorhynchos. Fairly common winter visitor (late October–March); especially common in spring Least Bittern Ixobrychus exilis hesperis. Uncom- (e.g., 17,500 at Río Colorado delta 20 March 1984; mon breeding resident (Grinnell 1928, Howell and REW, LRB). Uncommon non-breeding summer Webb 1992). visitor (Howell and Webb 1992), but including 450 Great Blue Heron Ardea herodias wardi. Com- at Laguna Salada 15 May 1989 (Howell and Pyle mon breeding resident. A. h. wardi includes A. h. 1990). treganzai and A. h. hyperonca as synonyms (Mayr Brown Pelican Pelecanus occidentalis and Cottrell 1979). californicus. Common resident on Gulf of Califor- Great Egret Ardea alba egretta. Common local nia, but breeds south of northernmost gulf (Ander- breeding resident (Mora 1989, 1991, Molina and son et al. 1976). Regularly occurs during summer Garrett 2001). (late April–mid-November) at inland bodies of wa- ter, such as Campo Geotérmico Cerro Prieto. Rare Snowy Egret Egretta thula subspp. Common local inland in winter (late November–February) along breeding resident (Palacios and Mellink 1992, rivers and at ponds and lakes. Molina and Garrett 2001). Most individuals are E. t. candidissima, including breeders on Isla Montague Phalacrocoracidae based on egg size (E. Mellink unpubl. data). De- Brandt’s Cormorant Phalacrocorax penicillatus. tailed measurements of skins and additional speci- Rare visitor to northern Gulf of California (Wilbur mens are needed; a few may be E. t. brewsteri from 1987, Russell and Monson 1998); recently discov- farther south on Baja California Peninsula, but ered breeding on Isla San Jorge in northeastern gulf which has reached Imperial Valley (Rea 1983). (Cervantes-S. and Mellink 2001). [Little Blue Heron Egretta caerulea]. No records; Double-crested Cormorant Phalacrocorax a rare summer visitor (May–July) to Salton Sea, auritus albociliatus. Common perennial visitor, with two breeding records, so probably a regular (al- reaching peak numbers in winter (Mellink et al. beit rare) visitor to northeastern Baja California. 1997); not known to breed, but breeds commonly at Salton Sea and uncommonly on lower Colorado Tricolored Heron Egretta tricolor ruficollis. Rare River (Rosenberg et al. 1991). summer vagrant, with three records from Río Colo- rado delta (Mellink et al. 1997) and an adult at Fregatidae Yurimuri 23 April 1984 (REW). Occurs nearly an- nually as a summer vagrant (mid-April–September) Magnificent Frigatebird Fregata magnificens. to Salton Sea, so presumably occurs more regularly Rare to uncommon post-breeding visitor, princi- in northeastern Baja California than records indi- pally late May–September (Ruiz-C. and cate. May occasionally occur in winter, given a Rodríguez-M. 1997). Some occur as early as handful of Salton Sea records at that season. E. t. mid-March (e.g., Campo Don Abel 19 March 1984; occidentalis is a synonym of E. t. ruficollis. REW, LRB), including a concentration of up to 20 (90% adult males) around San Felipe 28–29 March Reddish Egret Egretta rufescens dickeyi. Casual 1985 (REW). Species is monotypic, F. m. vagrant, probably mainly in fall (August–October). rothschildi being a synonym (Palmer 1962). Four records, from San Felipe 28-30 December 1970 (Devillers et al. 2001), 22 August 1992 (KAR, 36

TEW), near San Felipe 28 March 1985 (REW), and Cathartidae Río Colorado delta in fall 1993 (Mellink et al. Turkey Vulture Cathartes aura subspp. Common 1997). perennial visitor, most numerous in spring (Janu- Cattle Egret Bubulcus ibis ibis. Common breed- ary–May) and fall (August–October). Most records ing resident; colonized northeastern Baja California pertain to C. a. meridionalis, of which C. a. teter is a in mid-1960s, with breeding since early 1970s synonym, but nominate subspecies of Mexico (Mora 1997). reaches lower Colorado River valley (Rea 1983). Species may breed locally on eastern escarpment of Green Heron Butorides virescens anthonyi. mountains. Fairly common breeding resident. The type speci- ANSERIFORMES men of B. v. anthonyi was taken along the Río Al- amo at Seven Wells. Anatidae Black-crowned Night-Heron Nycticorax Fulvous Whistling-Duck Dendrocygna bicolor. nycticorax hoactli. Fairly common resident and Formerly, presumably a common breeding and breeder, the latter at least at Isla Montague. post-breeding visitor. Only one published record, of 2 at Río Colorado delta 24 January 1922 (Bancroft Threskiornithidae 1922), but 5 unpublished specimens at USNM be- White-faced Ibis Plegadis chihi. Common tween 18 April (1894, Río Alamo 13 km e. of non-breeding visitor, principally September–April Mexicali; USNM 133750) and 10 June (1915, Vol- (Patten et al. 1993) to Mexicali Valley and Valle de cano Lake [=Cerro Prieto]; USNM 259909, Río Colorado. Potentially breeds; e.g., three (of ±35 259910). Formerly numerous post-breeding visitor present) in full alternate plumage along Río Colo- and breeder around south end of Salton Sea (Garrett rado near Ejido Chiapas 10 May 1997 (RAH, and Dunn 1981), but has declined severely as a SNGH). The species has increased in southern Cali- breeder in Imperial Valley and few appear as fornia in past half-century (Shuford et al. 1996), in- post-breeding visitors now. Claimed breeding in cluding around Salton Sea (where breeding began in Baja California (Kramer and Migoya 1989) is un- 1954), but Wilbur (1987) seriously proven but probable. Despite its wide range, the underrepresented its status in northeast Baja Cali- species is monotypic, D. b. helva being a synonym fornia. The paucity of Mexicali Valley records in (Palmer 1976a). 1960s–1980s undoubtedly resulted from lack of coverage, not a lack of ibis. Greater White-fronted Goose Anser albifrons frontalis. Formerly numerous along Río Colorado Roseate Spoonbill Ajaia ajaja. Rare, irregular in “winter” (Saunders and Saunders 1981). Now a post-breeding (June–October) visitor (Bancroft rare spring transient (Patten et al. 1993). 1922, Grinnell 1926); no recent records (Wilbur 1987). Snow Goose Chen caerulescens caerulescens. Rare winter visitor (mid-October–mid-April); for- Ciconiidae merly more numerous (Murphy 1917).

Wood Stork Mycteria americana.RareRoss’s Goose Chen rossii. Numbers wintering post-breeding visitor (May–October). Formerly around south end of Salton Sea have increased 3–4 more numerous (Hill and Wiggins 1948, Wilbur orders of magnitude over past 50 years, so species 1987), but few recent records; e.g., up to 10 at Cam- may reach Mexicali Valley regularly, but only (ten- po Thy-Thy 27–28 August 1994 and nine at tative?) report is of several shot by hunters in De- Terrenos Indios 7 September 1995 (Ruiz-C. and cember 1950 or January 1951 (Saunders and Rodríguez-M. 1997). Saunders 1981). 37

Canada Goose Branta canadensis subspp. Fairly Mallard Anas platyrhynchos platyrhynchos.Un- common winter visitor (mid-October–April). Most common winter visitor (early Septem- are B. c. moffitti (Saunders and Saunders 1981). A ber–mid-April). Claimed breeding (Kramer and small portion (±5%) are presumed to be B. c. Migoya 1989) unfounded, although four on Río parvipes, of which B. c. taverneri is a synonym. A Hardy 4 August 1990 (TEW) probably summered. “flock” of B. c. minima was 8 km east of Cerro Prieto 10 February 1928 (CCL); a few reach Impe- Blue-winged Teal Anas discors. Casual winter vis- rial Valley each winter. Reasons are unknown for itor; two records, on Río Hardy 2 February 1981 attribution of B. c. leucopareia to Río Colorado (Wilbur 1987) and four at Mexicali 27 November (Friedmann et al. 1950), but it has occurred in adja- 1992 (TEW). Uncommon spring transient (proba- cent Sonora (Russell and Monson 1998). bly mid-February–early-May) and presumably un- common fall transient (mid-August–mid-October). Brant Branta bernicla nigricans. Uncommon Only migrant records are from spring: a pair on Río spring transient (mid-March–mid-May) first noted Hardy near Ejido Durango 25 March 2000 (MAP et in 1926 at San Felipe (Huey 1927). Most numerous al.), four at Campo Geotérmico Cerro Prieto 5 April at northern edge of Gulf of California, but multiple 1996 (TEW), a male on Río Alamo 13 km east of records inland at Campo Geotérmico Cerro Prieto Mexicali 21 April 1894 (USNM 133753), ±30 near (e.g., seven on 10 May 1997; RAH, SNGH). May Campo Mosqueda 22 April 1984 (REW), and one occasionally winter at Río Colorado delta (Price near La Ventana 23 April 1984 (REW). A hybrid 1899). Populations wintering in Gulf have in- male Blue-winged × Cinnamon Teal was near La creased substantially since mid-1960s (Llinas-G. Ventana 23 April 1984 (REW). Species is 1998, Russell and Monson 1998), so now likely monotypic, A. d. orphna being a synonym (Mayr much more frequent in northeastern Baja Califor- and Cottrell 1979). nia. Two summer records from Cerro Prieto, two 4 June 1998 (KLG) and four 26 August–4 September Cinnamon Teal Anas cyanoptera 1995 (KAR et al.). Attribution of the Atlantic Brant septentrionalium. Common transient in spring B. b. hrota to Río Colorado delta (Kramer and (late January–April) and fall (mid-July–October); Migoya 1989) is dubious (few valid records for uncommon breeder (Howell and Pyle 1990, Howell southern California; Garrett and Dunn 1981). and Webb 1992). Rare winter visitor.

Gadwall Anas strepera strepera. Fairly common Northern Shoveler Anas clypeata. Common tran- winter visitor (October–April). Claimed breeding sient and winter visitor (late July–early May); a few (Kramer and Migoya 1989) is unfounded. probably summer, but does not breed.

[Eurasian Wigeon Anas penelope]. Potential ca- Northern Pintail Anas acuta. Common transient sual winter visitor. One tenuous record of five and winter visitor (mid-July–mid-May); probably males, 18 females purportedly photographed at summers on occasion. Campo Sonora 8–10 December 1995 (Ruiz-C. and Green-winged Teal Anas crecca carolinensis. Rodríguez-M. 1997). Congregations of males are Common transient and winter visitor (August–early sometimes noted in southern California, but a report May); probably summers on occasion. of 18 females is undoubtedly erroneous given iden- tification difficulty. No more than two males have Canvasback Aythya valisineria. Rare winter visi- been found together in Salton Sink, where species is tor (October–April). nearly annual. Redhead Aythya americana. Fairly common win- American Wigeon Anas americana. Fairly com- ter visitor (October–April). Fairly common breeder mon winter visitor (September–April). around Salton Sea (Garrett and Dunn 1981), so probably breeds in Mexicali Valley, a statement sup- 38 ported by ±200 individuals at Campo Geotérmico at Salton Sea in spring and fall so presumably Cerro Prieto 4 September 1995 (SNGH et al.) and its moves through northeastern Baja California with status as “common” in summer on Ríos Hardy and some regularity. El Mayor (Ruiz-C. and Rodríguez-M. 1997). Bufflehead Bucephala albeola. Uncommon win- Ring-necked Duck Aythya collaris. Rare winter ter visitor (November–April). visitor (late October–mid-April); typically small numbers (<10) recorded, but ±30 were along Río Common Goldeneye Bucephala clangula Hardy 28 February 1987 (TEW). americana. Rare winter visitor (mid-November–mid-April), with late females at Greater Scaup Aythya marila nearctica. Two re- Volcano Lake [=Cerro Prieto] 3 May and 5 May cords of females, 2 km northeast of Cerro Prieto 7 1915 (USNM 259900, 259901). One summer re- February 1928 (Grinnell 1928, MVZ 52068) and cord, of a female at Campo Geotérmico Cerro Prieto near Río Colorado delta 20 March 1984 (REW, 1 September 2000 (SNGH et al.). LRB). A rare to uncommon winter visitor to Salton Sea, so presumably a rare winter visitor on Gulf of Hooded Merganser Lophodytes cucullatus. Rare California, but no records even for Sonora (Russell winter visitor (November–early March). Three or and Monson 1998). A. m. mariloides is a synonym four records (including returning birds) from Río (Banks 1986). Hardy: up to five at Campo Mosqueda 29 December 1991–11 January 1992 (Patten et al. 1993), ±20 Lesser Scaup Aythya affinis. Fairly common win- there 27 November 1992 (TEW), and four there 27 ter visitor (late October–April). January 1996 and 28 December 1996 (KAR). Also noted at Campo Sonora 4 November 1994–3 March Surf Scoter Melanitta perspicillata. Fairly com- 1995 and 10 December 1995 (Ruiz-C. and mon in winter (November–March) in northern Gulf Rodríguez-M. 1997). of California (Sanford et al. 1903); e.g., ±475 at San Felipe 22 February 1998 (RAE et al.). Common Common Merganser Mergus merganser spring transient (mid-March–May), as at San Felipe americanus. Generally a rare winter visitor in April 1926 (Huey 1927); may occasionally sum- (mid-November–early April), although 200 were at mer. One record inland, of three at Campo Campo Geotérmico Cerro Prieto 12 November Geotérmico Cerro Prieto 11 November 1995 (KAR, 1995 (KAR). CR). Red-breasted Merganser Mergus serrator.Un- White-winged Scoter Melanitta fusca deglandi. common spring migrant (late February-mid-May), Probably a rare spring transient (mid-March–May), mainly around Gulf of California, but with 16 inland but only one record, from Río Colorado delta in De- at Campo Mosqueda 23 February 1998 (RAE et al.) cember 1898 (Price 1899). Annual in spring and and one at Campo Geotérmico Cerro Prieto 19 May nearly annual at other seasons at Salton Sea. 2001 (KLG). Uncommon winter visitor (Novem- ber–March) on gulf; casual elsewhere, with 10 at [Black Scoter Melanitta nigra americana]. With Campo Mosqueda 14 January 1989 (TEW), two ±20 individuals recorded at Salton Sea, all in sum- there 30 December 1999 (MAP), and three along mer and winter, this species presumably moves Río Hardy 27 November 1992 (TEW). Species is through northeastern Baja California to some de- monotypic, M. s. schioleri being a synonym gree, but no regional records and those for Sonora (Palmer 1976b). are not verified (Russell and Monson 1998). Ruddy Duck Oxyura jamaicensis rubida. Com- Long-tailed Duck Clangula hyemalis.Casualmon winter visitor (October–mid-April); presum- spring vagrant. One sight record from San Felipe 1 ably breeds uncommonly in Mexicali Valley and April 1926 (Huey 1927, cf. Grinnell 1928). Annual around Río Colorado. 39

FALCONIFORMES A. c. mexicanus of Pacific Northwest is recognized Accipitridae (see Whaley and White 1994), then many migrant and wintering birds would pertain to it, but potential Osprey Pandion haliaetus carolinensis. Common breeders and other migrants/winterers would be A. breeding resident around Gulf of California (Henny c. cooperi. and Anderson 1979). No recent breeding in region covered herein (Anderson et al. 1976), but bred for- Harris’s Hawk Parabuteo unicinctus superior. merly at San Felipe (Huey 1927) and breeds near Formerly common breeding resident (Grinnell Río Colorado delta in Sonora (Mellink and Palacios 1928, WFVZ 83655), but not recorded since 1993) and at Puertecitos to south (EP). Fairly com- mid-1920s. However, population fluctuations ir- mon non-breeding visitor nearly throughout, regularly bring birds back into southern California though uncommon to rare in Mexicali Valley and (Patten and Erickson 2000) and probably also north- rare in open desert. eastern Baja California. Two recent records from Río Colorado delta portion of Sonora, from El White-tailed Kite Elanus leucurus majusculus. Doctór 9 April 1994 (Russell and Monson 1998) Rare fall and winter visitor (mid-August– and El Golfo de Santa Clara 5 December 1999 mid-April), principally to Mexicali Valley, where (KLG). potentially a rare breeding resident (Patten et al. 1993). Small numbers regularly reach Río Colo- Red-shouldered Hawk Buteo lineatus elegans. rado (Russell and Monson 1998, TEW, MAP). Two records of juveniles from Mexicali, 14 January 1989 and 14 December 1994 (TEW). A rare Bald Eagle Haliaeetus leucocephalus subspp. fall/winter dispersant (late August–April) around Rare winter visitor (late October–mid-March). Salton Sea, where it has increased sharply since late Several older records for Río Colorado delta (e.g., 1970s, so date span of occurrence likely broader. Stone and Rhoads 1905) have been questioned Reports from Rhoads (Murphy 1917) are inconclu- (Grinnell 1906). Four recent records: three at La sive. Ventana 20 March 1984 (REW, LRB), three at Laguna Salada 7–8 January 1987 (AMS, MBA Swainson’s Hawk Buteo swainsoni. Rare tran- “Bulletin Board” 1:4 [April 1987]), an immature at sient in spring (mid-February–mid-May) and prob- Campo Mosqueda 14 January 1989 (Patten et al. ably in fall (early October–early November). Three 1993), and an adult there 30 December 1999 recent records of wintering birds, a dark-morph ju- (MAP). Of note are records from Sonora portion of venile near Ejido Chiapas 10 January 1994 (SNGH, Valle de Río Colorado at Ciénega de Santa Clara, El PP) and up to two adults (one dark, one light) at Doctór, and El Golfo de Santa Clara (Abarca et al. Ciudad Victoria 10–15 December 1994 (KAR et 1993, EP, KLG). Based on specimens from south- al.). Winters sparingly in adjacent Imperial Valley ern California, wintering birds are presumed to be (beginning in 1990s). northerly H. l. alascanus, but nominate subspecies Red-tailed Hawk Buteo jamaicensis subspp. (which breeds in Arizona and Sonora) may occur. Widespread in western North America, B. j. calurus Northern Harrier Circus cyaneus hudsonius. is a common winter visitor (late August–early Common winter visitor (mid-July–early May). May). Breeds uncommonly, principally around Río Colorado and at eastern edge of Peninsular Range Sharp-shinned Hawk Accipiter striatus velox. escarpment. A dark immature at Mexicali 1–15 De- Uncommon winter visitor (mid-August–April). cember 1994 (KAR et al.) was B. j. harlani, a rare winter visitor to the Salton Sink. Cooper’s Hawk Accipiter cooperi. Uncommon winter visitor (early August–early May); perhaps a Ferruginous Hawk Buteo regalis. Rare winter former breeder on Río Colorado (Murphy 1917). If visitor (October–mid-March), probably annually in 40 small numbers (Patten et al. 1993). An extremely Prairie Falcon Falco mexicanus. Uncommon late bird was photographed at San Felipe 28 April winter visitor (September–April). May breed on 1991 (REW). rocky slopes of low-elevation mountains. [Rough-legged Hawk Buteo lagopus GALLIFORMES sanctijohannis]. Wilbur (1987) did not list species Odontophoridae for Baja California, despite a published record for 1962 (Audubon Field Notes 16:365, Erickson et al. Gambel’s Quail Callipepla gambelii gambelii. 2001), but no records for northeastern Baja Califor- Common breeding resident south to La Ventana(see nia. Rare, nearly annual winter visitor (late Octo- Wilbur 1987). Uncommon to fairly common farther ber–February) to Salton Sea region, especially south, reaching range limit at south edge of Bahía Imperial Valley, where a light-morph juvenile was San Felipe (RAH, SNGH). only ±10 km north-northwest of international bor- der 11 December 1994 (MAP et al.). California Quail Callipepla californica californica. Fairly common breeding resident Falconidae around San Felipe (Grinnell 1928, MVZ 47907, 47908). Sympatric with the Gambel’s Quail south Crested Caracara Caracara cheriway. Former, from open desert north of San Felipe (REW); poten- presumably rare, winter visitor to Río Colorado tial hybrids have been noted (Wilbur 1987). C. c. delta. Four records of seven individuals before plumbea is a synonym (SDNHM specimens from 1930, one at “head of Río Hardy” 7 December 1896 type locality of each are not separable). (SDNHM 349), two on upper Río Hardy in Febru- ary 1905 (Stone and Rhoads 1905), one along Río GRUIFORMES Colorado 16 km south of United States border 21 Rallidae December 1922 (SDNHM 10492), and three (one collected) 11 km west southwest of Pilot Knob 15 [Black Rail Laterallus jamaicensis coturniculus]. March 1928 (Grinnell 1928, MVZ 52104). Species As noted by Wilbur (1987), known from lower Col- is monotypic, C. c. audubonii being a synonym orado River just north of Mexico border (Rosenberg (Dove and Banks 1999). et al. 1991), but no records for northeastern Baja California. Rare breeding resident at various lo- American Kestrel Falco sparverius subspp. Nom- cales in Imperial Valley, including All American inate subspecies is a common breeding resident, Canal near Calexico <1 km north of Mexico border with numbers augmented in winter (Am. Birds 33:897); also known from Ciénega de (mid-August–May). There are several winter speci- Santa Clara and El Doctór, Sonora (OH, KLG). mens of southerly F. s. peninsularis from Río Colo- rado delta region 14 October 1927–4 February 1928 Clapper Rail Rallus longirostris yumanensis.Un- (Grinnell 1928, MVZ 52101–52103). common breeding resident along Río Colorado and Río Hardy (Ruiz-C. and Rodríguez-M. 1997), with Merlin Falco columbarius columbarius. Rare probably some winter influx to the delta. Perhaps winter visitor (late September–early April). F. c. half of world population breeds in Río Colorado bendirei is generally treated as a synonym (Palmer delta at Ciénega de Santa Clara, Sonora (Abarca et 1988). F. c. richardsoni of Great Plains may occur al. 1993). on occasion, but no records. Virginia Rail Rallus limicola limicola. Uncom- Peregrine Falcon Falco peregrinus anatum. Rare mon resident and presumed breeder along Ríos Col- perennial visitor, mainly along Gulf of California; orado and Hardy (breeds uncommonly in Salton breeds or formerly bred on Rocas Consag (Bancroft Sink); numbers probably augmented in winter. 1927). 41

Sora Porzana carolina. Uncommon winter visitor Also recently noted north of San Felipe between 28 (August–early May). Possibly breeds on Río Hardy March (1985, four pairs at Campo Los Amigos and (OH). Campo Don Abel; REW) and 4 August (1990; TEW), suggesting a small population persisted until Common Moorhen Gallinula chloropus early 1990s and perhaps to present (E. Palacios in cachinnans. Fairly common breeding resident. litt.).

American Coot Fulica americana americana. Semipalmated Plover Charadrius semipalmatus. Common breeding resident, with higher numbers in Fairly common transient in spring winter. (mid-March–mid-May) and fall (July–October); Gruidae uncommon winter visitor. Sandhill Crane Grus canadensis subspp. Rare Killdeer Charadrius vociferus vociferus. Com- winter visitor (late October–March); formerly com- mon breeding resident. mon (Murphy 1917), but no recent records. Nomi- nate subspecies of Alaska and northern Canada Mountain Plover Charadrius montanus. One re- predominates. Because G. c. tabida is predominant cord, of a lone bird south of Algodones 16 Novem- subspecies wintering in lower Colorado River val- ber 1994 (TEW). Principal wintering site for the ley (Rosenberg et al. 1991), it likely occurred in species is Imperial Valley (Garrett and Dunn 1981), northeastern Baja California, but no specimens. where there are records south to international bor- der. Species has been attributed to areas near Bahía CHARADRIIFORMES Adair, northwestern Sonora, in winter (May 1976). Charadriidae Thus, species undoubtedly winters in agricultural expanses of northern Mexicali Valley and probably Black-bellied Plover Pluvialis squatarola. Com- migrates through to some degree. mon transient and winter visitor (July–mid-May); Haematopodidae probably summers annually (see Mellink et al. 1997). American Oystercatcher Haematopus palliatus frazari. Uncommon perennial visitor to northern Snowy Plover Charadrius alexandrinus nivosus. Gulf of California, most numerous in spring and fall Uncommon breeding resident along Gulf of Cali- (Mellink et al. 1997). A pair at Isla Montague 10 fornia and at Campo Geotérmico Cerro Prieto June 1993 may have been breeding (Peresbarbosa (Molina and Garrett 2001). Also breeds in Río Col- and Mellink 1994). Breeding confirmed at Isla orado delta at Ciénega de Santa Clara, Sonora Montague (EM) 7 May 1998 (two pairs with one (Mellink et al. 1996). egg each) and 27 May 1999 (one pair with one egg). Wilson’s Plover Charadrius wilsonia beldingi. Recurvirostridae Uncommon winter visitor (mid-September–early April). Recorded at Isla Montague 21 September Black-necked Stilt Himantopus mexicanus 1997 (RAR, MF) and several additional records mexicanus. Fairly common breeding resident. from Río Colorado delta (Mellink et al. 1997). Ap- American Avocet Recurvirostra americana. parently bred in San Felipe area before extensive Common perennial visitor; breeds at least occasion- human settlement (Devillers et al. 2001) but now ally at Campo Geotérmico Cerro Prieto (Molino and unconfirmed as a breeder north of Puertecitos Garrett 2001, SNGH, EM). Breeds in Río Colorado (Palacios and Mellink 1996). However, two males delta at Ciénega de Santa Clara, Sonora (Mellink et and a female at Estero La Ramada north of Campo al. 1996). Don Abel 20 June 1991 included a pair acting agitatedly, as if egg/chicks nearby (SNGH, SW). 42

Scolopacidae Long-billed Curlew Numenius americanus. Common transient and winter visitor (July–early Greater Yellowlegs Tringa melanoleuca. Fairly May); probably oversummers in small numbers, as common transient and winter visitor (July–early in adjacent Imperial Valley. Species is monotypic, May). N. a. parvus being a synonym (Grinnell and Miller Lesser Yellowlegs Tringa flavipes. Fairly common 1944, Phillips et al. 1964). transient (late March–April, July–October); un- Marbled Godwit Limosa fedoa fedoa. Common common in winter (Patten et al. 1993). transient and winter visitor (July–mid-May); Solitary Sandpiper Tringa solitaria cinnamomea. non-breeders probably summer regularly. Rare fall transient 22 August (1992, Mexicali Val- Ruddy Turnstone Aremaria interpes interpes. ley; TEW) to 29 September (1996, near Cerro Fairly common transient (April–May, July–Sep- Prieto; KLG), with passage presumably as early as tember) and winter visitor, mainly at Gulf of Cali- late July. Two spring 1894 records from Río Alamo fornia. A flock of 25 was inland at Campo 13 km east of Mexicali, 18 April (USNM 135484) Geotérmico Cerro Prieto 10 May 1997 (RAH, and 20 April (USNM 135485). One winter record, SNGH). perhaps tentative, from Río Hardy in December 1896 (Grinnell 1928). Black Turnstone Arenaria melanocephala.Un- common transient (April–May, July–September) Willet Catoptrophorus semipalmatus inornatus. and winter visitor at Gulf of California. Common transient and winter visitor (late June–mid-May); some oversummer. Surfbird Aphriza [Calidris] virgata. Common spring transient (mid-March–early May) in north- Wandering Tattler Heteroscelus incanus.Un- ern Gulf of California (Huey 1927, Wilbur 1987); common winter visitor and transient along Gulf of uncommon winter visitor on gulf. California coast, most often noted during north- bound migration in spring. One was collected in- Red Knot Calidris canutus roselaari. Fairly com- land at a playa of Río Alamo 12 km east of Mexicali mon transient in spring (mid-March–May), when 27 or 28 April 1894 (Mearns 1907:130, USNM more numerous (e.g., ±1500 in San Felipe area 133767). Grinnell (1928) said whereabouts of spec- 28–29 March 1985; REW), and fall (July–October) imen were unknown, but it might be USNM and winter visitor. Mainly occurs around Gulf of 133767. Original collection data indicate it was California, but seven were at Campo Geotérmico taken in Baja California at a “Laguna of Salton Cerro Prieto 23 July 1995 (KAR) and two were River” [= Alamo River] 27–28 April 1894 by E. A. there 1 September 2000 (RAH et al.). See Patten et Mearns (J. P. Dean in litt.), so reasons for Grinnell’s al. (in press) for subspecies treatment. statements are unknown. Sanderling Calidris alba. Uncommon transient Spotted Sandpiper Actitis macularia. Fairly com- (mid-March–May, late July–September) and winter mon transient and winter visitor (late visitor; most numerous at Gulf of California. July–mid-May). Semipalmated Sandpiper Calidris pusilla. Proba- Whimbrel Numenius phaeopus hudsonicus. bly a rare but regular spring and fall transient (late Common transient in spring (mid-March–May) and April–May, late July–early September). Only one fall (late July–September), but especially the for- record, near Campo Don Abel, 16 km north of San mer. One winter record, 25 km southeast of Felipe, 21 August 1984 (Wurster and Radamaker Mexicali 29 December 1991 (Patten et al. 1993). 1992). 43

Western Sandpiper Calidris mauri. Common Short-billed Dowitcher Limnodromus griseus transient and winter visitor (late June–mid-May); caurinus. Common spring transient (March–early most numerous shorebird in Río Colorado delta May); fairly common fall transient (July–October). (Mellink et al. 1997). Given its status in Sonora (Russell and Monson 1998), presumably an uncommon winter visitor Least Sandpiper Calidris minutilla. Common along Gulf of California. L. g. hendersoni of the transient and winter visitor (late June–early May). Great Plains may occur on occasion, but no records. Baird’s Sandpiper Calidris bairdii. Presumably a Non-breeders probably summer regularly. rare fall transient (mid-July–early October), but Long-billed Dowitcher Limnodromus only two records, of three near Mexicali 7 [not 9] scolopaceus. Common transient and winter visitor September 1987 (Patten et al. 1993) and one at (July–mid-May); a few non-breeders probably Primero Estero that same day (TEW). summer each year.

[Pectoral Sandpiper Calidris melanotos]. No re- Common Snipe Gallinago gallinago delicata. cords but may occur on rare occasion. Rare fall Fairly common but somewhat secretive transient transient (September–November) at Salton Sea; no and winter visitor (late August–April). verified records for Sonora (Russell and Monson 1998). Wilson’s Phalarope Phalaropus tricolor. Com- mon transient in spring (mid-March–mid-May) and Dunlin Calidris alpina pacifica. According to fall (mid-June–October). Roughly 5000 were at Wilbur (1987) “not recorded north of La Paz on Campo Geotérmico Cerro Prieto 23 July 1995 Gulf of California coast,” but presumably a fairly (KAR). common spring transient (April–May) and uncom- mon fall transient and winter visitor (late Septem- Red-necked Phalarope Phalaropus lobatus. ber–March). Recorded at Campo Sonora 3–4 Common transient in spring (April–May) and fall February 1995 (Ruiz-C. and Rodríguez-M. 1997) (July–November). Roughly 10,000 were at Campo and Campo Geotérmico Cerro Prieto 11 November Geotérmico Cerro Prieto 23 August 1997 (MAP et 1995 (KAR, CR). Numerous around Río Colorado al.) and 7500+ were there 4 September 2000 (MAP, delta in 1993–1994, especially spring 1994 BDS). Perhaps winters on Gulf of California. (Mellink et al. 1997). A specimen collected at Cam- po Sonora on the aseasonal date of 27 August 1994 Red Phalarope Phalaropus fulicaria.Casual (UABC 651; Ruiz C. and Rodríguez M. 1997) is ac- spring vagrant; one record, of an adult male at San tually a Western Sandpiper. Felipe 17 April 1926 (Huey 1927, MVZ 47871). Probably rare fall vagrant given that fall records Stilt Sandpiper Calidris himantopus. Presumably (July–November) predominate at Salton Sea. a regular, though uncommon, transient in spring Laridae (mid-April–mid-May) and fall (mid-July– mid-September), but only one record, from Campo Pomarine Jaeger Stercorarius pomarinus. Three Geotérmico Cerro Prieto 23 August 1997 (MAP et records from Campo Don Abel, one 20 March 1984 al.). A few hundred winter regularly in Imperial (REW, LRB), five 22 April 1984 (REW), and 28 on Valley, hundreds pass through south end of Salton 27 April 1991 (REW). An unidentified jaeger was Sea each year, and small numbers winter in western near San Felipe 29 March 1985 (REW). Wilbur Mexico south of southern Sinaloa. Still, there are (1987) listed but one Gulf of California record, and few records for Sonora (Russell and Monson 1998), Russell and Monson (1998) did not accept any so perhaps migrants routinely fly over northeastern Sonora records, but there are ±16 records for Salton Baja California and northwestern Mexico. Sea, including a flock of 27 adults 4 May 1986 (Am. Birds 41:147), so perhaps regular in northeastern 44

Baja California. An unidentified jaeger north of San Bonaparte’s Gull Larus philadelphia. Fairly com- Felipe 28 February 1987 (TEW) indicates that this mon to uncommon transient and winter visitor (late species or the following one winters occasionally in October–May); most numerous in spring northern gulf. (March–May).

Parasitic Jaeger Stercorarius parasiticus. Pre- Heermann’s Gull Larus heermanni. Common pe- sumed rare fall transient (late August to rennial visitor (most numerous as post-breeding dis- mid-November), especially around head of Gulf of persant, July–November) to northern Gulf of California, as this species is regular at Salton Sea in California and probably through inland northeast- fall. A juvenile was inland at Campo Geotérmico ern Baja California, as this species reaches Salton Cerro Prieto 4 September 1995 (SNGH et al.). In Sea annually. spring, six were at Campo Don Abel 19 March 1984 (REW, LRB) and one was there 22 April 1984 [Mew Gull Larus canus brachyrhynchus]. No re- (REW). cords but 2–3 occur annually in winter (Novem- ber–March) at Salton Sea, so it should occur in Long-tailed Jaeger Stercorarius longicaudus northeastern Baja California. pallescens. Casual fall vagrant. Two records from Campo Geotérmico Cerro Prieto, a juvenile 26 Au- Ring-billed Gull Larus delawarensis. Common gust–4 September 1995 (KAR et al.) and an adult 4 winter visitor (late July–early May); uncommon September 1995 (SNGH et al.). non-breeding summer visitor.

Laughing Gull Larus atricilla. Fairly common California Gull Larus californicus subspp. Com- breeder at Isla Montague (Palacios and Mellink mon winter visitor (late July–early May), with larg- 1992) and rare breeder at Campo Geotérmico Cerro est numbers around Río Colorado delta in Prieto (Molina and Garrett 2001); fairly common March–April (Mellink et al. 1997); uncommon summer visitor elsewhere, mainly non-breeding summer visitor. Most are presumably June–mid-October but recorded as early as 19 nominate subspecies (e.g., adult male at San Felipe March (1984, 30 at Campo Don Abel; REW, LRB). in April 1926; SDNHM 10466) but L. c. Rare in winter away from gulf from 27 November albertaensis undoubtedly occurs, though probably (1992, eight along Río Hardy; TEW) to 28 February <15% of birds on basis of specimens from Salton (1987 [not 1991], Río Hardy; Patten et al. 1993), Sea. mainly from Río Hardy but with records north to Herring Gull Larus argentatus smithsonianus. Mexicali (e.g., four along Río Nuevo 14 December Fairly common winter visitor (mid-September– 1994; TEW). L. a. megalopterus is a synonym. mid-April). Franklin’s Gull Larus pipixcan. Rare spring tran- Thayer’s Gull Larus [glaucoides] thayeri. Rare sient (mid-March–early June). Four records from winter visitor to Gulf of California (late Octo- Campo Geotérmico Cerro Prieto, adults 10 May ber–early April). Occasionally uncommon; e.g., 1997 (RAH, SNGH), 14 March 1998 (KAR, HG), “≤ 25" at San Felipe 28-30 December 1970 and 19 May 2001 (2; KLG) and a first-summer bird (Devillers et al. 1971, SDNHM 10362). “Thayer’s 4 June 1998 (KLG, EM). Individuals also recorded Gull” is probably best treated as a subspecies of the at Campo Don Abel 19 March 1984 (REW, LRB) Iceland Gull L. glaucoides (Godfrey 1986, Sibley and Laguna Salada 23 April 1984 (REW). Con- and Monroe 1990:256, Gibson and Kessel 1997, sidering status at Salton Sea, probably rare fall tran- Pittaway 1999). sient (August–October) and summer visitor, but only one record at these seasons, from Campo Yellow-footed Gull Larus livens. Common breed- Geotérmico Cerro Prieto 20 August 1995 (KLG, ing resident on Gulf of California, but not in north- TEW). eastern Baja California (Anderson et al. 1976). 45

Large numbers (±2000 birds) disperse inland on occasion. Species is generally treated as through Mexicali Valley to Salton Sea each monotypic, X. s. woznesenskii being a synonym. May–November (Patten 1996). Most occur along northern gulf beginning in March and April (e.g., Gull-billed Tern Sterna nilotica vanrossemi. San Felipe 29 March 1928; FMNH 158569). Basis Common breeder (mid-March–mid-October) at Isla for claimed breeding on Rocas Consag (Grinnell Montague (Palacios and Mellink 1993) and Campo 1928) is unknown. Geotérmico Cerro Prieto (Molina and Garrett 2001). Regular at San Felipe (Wilbur 1987, Howell Western Gull Larus occidentalis wymani. Rare and Webb 1992). Forages over fresh water during winter visitor (October–March). Four records for breeding season; e.g., Río Hardy 3 May 1992 and San Felipe, one 29 December 1970 (Devillers et al. Canal Independencia 3 May 1994 (EM). 1971), up to two 22–23 February 1998 (SNGH et al.), one 23 September 1998 (HG), and two photo- Caspian Tern Sterna caspia. Uncommon breeder graphed 25 March 2000 (MAP et al.). Also an adult (mid-April–October) at Campo Geotérmico Cerro at Campo Don Abel 22 April 1984 (REW). Annual Prieto (Molina and Garrett 2001); fairly common in small numbers at Salton Sea and increasing in perennial visitor elsewhere. Might breed at Isla northern Gulf of California in adjacent Sonora Montague (EP, EM). (KLG). Subspecies determination based on speci- Royal Tern Sterna maxima maxima. Fairly com- mens and careful sight records for Salton Sea. mon resident along Gulf of California (Wilbur Glaucous-winged Gull Larus glaucescens. Pre- 1987), breeding at Isla Montague (Palacios and sumed rare winter visitor (mid-October– Mellink 1993), though not annually and greatly mid-April). Only four records, all from San Felipe, fluctuating in number; e.g., 135 nests 7 May 1998, “a few individuals” 22 March–25 April 1926 (Huey but only 16 nests 27 May 1999 (EM). Two at Cam- 1927, MVZ 47832), third-winter bird 29 March po Geotérmico Cerro Prieto 10 May 1997 (SNGH, 1985 (REW), and first-winter birds 14–15 January RAH) were inland. 1989 (up to two; TEW et al.) and 30 December 1999 Elegant Tern Sterna elegans. Potential breeding (MAP). Probably regular in small numbers. on Isla Montague (Palacios and Mellink 1992) was Glaucous Gull Larus hyperboreus barrovianus. later confirmed (Palacios and Mellink 1993), re- Three winter reports. One (perhaps tentative) from cently with 160 nests 7 May 1998 and 2 nests 27 San Felipe 11 March 1951 (Audubon Field Notes May 1999 (EM). Otherwise a fairly common 5:227). First-winter birds photographed at Laguna non-breeding and post-breeding (April–October) Salada 7–8 January 1987 (AMS, MBA “Bulletin visitor to Gulf of California (Wilbur 1987), with re- Board” 1:4 [April 1987]) and San Felipe 20 Febru- cords as early as 19 March (1984, 15 at Campo Don ary 1997 (KAR; Figure 3-8). Nearly annual in win- Abel; REW, LRB). One inland record: adult at ter (December–March) at Salton Sea and five Campo Geotérmico Cerro Prieto 19 May 2001 records for northwestern Sonora, four from Puerto (KLG). Peñasco (Russell and Monson 1998) and one photo- Common Tern Sterna hirundo hirundo. Presum- graphed at El Golfo de Santa Clara 26 January 1997 ably a common fall transient (late July– (KLG). mid-November), but few records; e.g., eight in San [Sabine’s Gull Xema sabini]. No records. Given Felipe area 4 August 1990 (TEW) and adult and 2–3 multitude of records for Salton Sea, principally in juveniles at Campo Geotérmico Cerro Prieto 4 Sep- fall (mid-September–mid-October), and two tenta- tember 1995 (SNGH et al.). Presumably an uncom- tive reports for Sonora (Russell and Monson 1998), mon spring transient (late April–mid-June). Winter likely passes through northeastern Baja California reports for the northern Gulf of California (e.g., May 1976) are questionable. 46

[Arctic Tern Sterna paradisaea]. Not recorded but COLUMBIFORMES ±25 records from Salton Sea, mainly in June, so spe- Columbidae cies likely moves through northeastern Baja Cali- fornia. White-winged Dove Zenaida asiatica mearnsi. Common breeder (late March–September). Win- Forster’s Tern Sterna forsteri. Uncommon ters from San Felipe southward; one record else- breeder at Campo Geotérmico Cerro Prieto (Molina where, 18 km southwest of La Ventana 17–18 and Garrett 2001). Fairly common perennial visitor December 1997 (HG). elsewhere (see Howell and Webb 1992), most nu- merous April–October. Mourning Dove Zenaida macroura marginella. Common breeding resident. Least Tern Sterna antillarum subsp.? Uncommon breeder on Isla Montague (Palacios and Mellink Inca Dove Columbina inca. Uncommon to locally 1992) and at estuaries north of San Felipe (Palacios common (e.g., 40 at Mexicali 14 December 1994; and Mellink 1996). Otherwise uncommon spring TEW) resident and presumed breeding. Recent col- and summer visitor (early April–late August), onist, first recorded at Mexicali 4 August 1984 mainly along Gulf, but noted along Río Hardy in (REW); early claims from upper Río Hardy (Stone spring (Ruiz-C. and Rodríguez-M. 1997) and 50 and Rhoads 1905) are suspect (Grinnell 1928). Nu- were at Laguna Salada 21 August 1984 (REW). merous records for Mexicali area and Algodones Least Tern subspecies in Mexico are in need of criti- (Patten et al. 1993, SNGH, KAR et al.). Also re- cal review and potential revision (Patten and corded at San Felipe, with two adults and an appar- Erickson 1996). Breeders probably are S. a. ent juvenile 10 May 1997 (RAH, SNGH). mexicana of adjacent Sonora, but attribution of breeders and validity of subspecies have not been Common Ground-Dove Columbina passerina properly assessed (Palacios and Mellink 1996). pallescens. Common breeding resident. CUCULIFORMES Black Tern Chlidonias niger surinamensis. Com- mon transient in spring (late April–early June) and Cuculidae fall (August–September); sometimes numerous (e.g., thousands in northern Gulf of California dur- Yellow-billedCuckoo Coccyzus americanus. For- ing late September 1997; RAR, MF). May summer merly fairly common breeder along Río Colorado, on occasion. but now essentially extirpated throughout lower Colorado River valley (Rosenberg et al. 1991). Pre- Black Skimmer Rynchops nigra nigra. Common sumably formerly bred along Río Hardy, as evi- breeder (April through November) at Isla Montague denced by four 11 km east of Cerro Prieto 2–15 June (Palacios and Mellink 1993, Peresbarbosa and 1928 (Grinnell 1928, MVZ 52911-52914). One re- Mellink 1994) and Campo Geotérmico Cerro Prieto cent record, of two calling adults at Murguia, Río (Molina and Garrett 2001). Uncommon to rare visi- Hardy, 9 July 1995 (KAR). C. a. occidentalis is not tor elsewhere, with some wintering on northern diagnosable, so species is best considered Gulf. monotypic (Banks 1988, Patten et al. in press). Alcidae Greater Roadrunner Geococcyx californianus. Fairly common breeding resident. Craveri’s Murrelet Synthliboramphus craveri. May breed on Rocas Consag (Bancroft 1927) and STRIGIFORMES presumably resident on waters of northern Gulf of Tytonidae California, but seldom noted and may withdraw southward in winter. Barn Owl Tyto alba pratincola. Uncommon breeding resident. 47

Strigidae 2001), Campo Sonora 12 January 1982 (DES), and Campo Mosqueda 10 January 1994 (SNGH, PP) Western Screech-Owl Otus kennicottii subspp.O. and 12 November 1994 (TEW). Two or three were k. yumanensis is an uncommon breeding resident also reported by Rhoads in February 1905 (Stone along ríos Colorado and Hardy and low-elevation and Rhoads 1905). C. a. inferior of southern Baja canyons of eastern escarpment of various mountain California is a synonym (Dickerman 1985). ranges (just outside region covered). Also in settled areas with adequate tree cover, whether Populus or Common Poorwill Phalaenoptilus nuttallii Eucalyptus, particularly in Mexicali Valley (e.g., in subspp. P.n. hueyi is a fairly common breeding resi- Washingtonia at Mexicali 4 September 2000; dent along Río Colorado. Nominate subspecies pre- MAP). Based on habitat and subspecies’ distribu- sumably migrates through in small numbers in tion, birds in vicinity of San Felipe (e.g., 1 Septem- spring (mid-April–mid-May) and fall (October), ber 2000; SNGH et al.) presumably O. k. but only record is of a male at Cerro Prieto 20 April cardonensis of central Baja California Peninsula. 1905 (USNM 197778). Friedmann et al. (1950) mistakenly attributed P.n. californicus to northeast- Great Horned Owl Bubo virginianus pallescens. ern Baja California (they undoubtedly meant Fairly common breeding resident. “northwestern”). [Elf Owl Micrathene whitneyi whitneyi]. Pre- APODIFORMES sumed former breeder (March–August) on Río Col- orado, but no records (Wilbur 1987) and now nearly Apodidae extirpated in lower Colorado River valley [Black Swift Cypseloides niger borealis]. No re- (Rosenberg et al. 1991). cords, but presumably a casual spring transient Burrowing Owl Athene cunicularia hypugaea. (mid-May–early June). Fairly common breeding resident, with a decrease Vaux’s Swift Chaetura vauxi vauxi. Common in winter (Palacios et al. 2000); the Río Colorado spring transient (mid-April to mid-May); uncom- delta is its stronghold in Baja California. mon fall transient (September–mid-October). Long-eared Owl Asio otus wilsonianus. Casual White-throated Swift Aeronautes saxatalis winter vagrant. One record, ±9 km south of San saxatalis. Fairly common winter visitor (Septem- Felipe 22 February 1998 (RAE et al.). This bird was ber–mid-May). Potentially breeds in some canyons hooting much of the night, so was perhaps on breed- on eastern escarpment of mountains. Forages over ing territory (SNGH), but nesting unknown in vast areas away from breeding sites (Grinnell and Salton Sink and sporadic in lower Colorado River Miller 1944, Garrett and Dunn 1981), so even mid- Valley (Rosenberg et al. 1991). summer records should not be construed as evi- Short-eared Owl Asio flammeus flammeus. Rare dence of local breeding. winter visitor (mid-October–mid-March), princi- Trochilidae pally around Río Colorado, but probably also in Mexicali Valley. Black-chinned Hummingbird Archilochus alexandri. Uncommon migrant and breeder CAPRIMULGIFORMES (mid-March–mid-September). Caprimulgidae Anna’s Hummingbird Calypte anna. Uncom- Lesser Nighthawk Chordeiles acutipennis mon, local resident; presumed breeder in Mexicali texensis. Common breeder (mid-March– Valley. Began breeding along lower Colorado River mid-October). Winters rarely, with four records, in 1962 (Rosenberg et al. 1991) and now established from San Felipe 14 January 1967 (Devillers et al. there, so probably breeds on the Río Colorado. Un- 48 common to fairly common winter visitor elsewhere, nia (Patten et al. 1993). Species is monotypic, S. v. south to San Felipe; e.g., two at Las Palmas 31 De- appalachensis being a synonym. cember 1999 (MAP). Red-naped Sapsucker Sphyrapicus nuchalis. Costa’s Hummingbird Calypte costae.FairlyRare winter visitor (late September–mid-March), common breeding resident. approaching uncommon on Río Colorado. An ap- parent hybrid Red-naped × Red-breasted S. ruber [Calliope Hummingbird Stellula [Selasphorus] Sapsucker was at Campo Mosqueda 15 December calliope]. Presumably a rare spring transient (late 1994 (TEW). March–early May), but no records. Red-breasted Sapsucker Sphyrapicus ruber Rufous Hummingbird Selasphorus rufus.Un- daggetti. Casual winter visitor. One or two records common spring transient (mid-March–April); rare from Campo Mosqueda (perhaps a returning bird) fall transient (mid-July–mid-September). An early 27 November 1992 and 15 December 1994 (TEW). adult male was collected in Sierra Cucapah 24 Feb- Species is casual east of the Sierra Ne- ruary 1905 (Stone and Rhoads 1905, ANSP 48293). vada-Peninsular Range axis. There are but three records of Allen’s Hummingbird in the Salton Sink, where the Rufous Hummingbird Ladder-backed Woodpecker Picoides scalaris is regular, so records of Selasphorus spp. for north- subspp. Fairly common breeding resident. P. s. eastern Baja California are assumed to be S. rufus. cactophilus occurs in Mexicali Valley (where un- common) east through Río Colorado delta. P. s. CORACIIFORMES eremicus occurs around San Felipe north to Sierra Alcedinidae las Pintas (Grinnell 1928). Misidentified P.scalaris from San Felipe were named a distinct subspecies, Belted Kingfisher Ceryle alcyon. Fairly common P. nuttallii longirostrata (Huey 1927:27) of winter visitor (August–mid-May). C. a. caurina is a Nuttall’s Woodpecker P. nuttallii (see Grinnell synonym (Mayr and Short 1970). 1928:121). PICIFORMES Northern Flicker Colaptes auratus subspp. Fairly Picidae common winter visitor (late September to early April). Based on specimens from Salton Sea and Gila Woodpecker Melanerpes uropygialis lower Colorado River (SDNHM), most (±70%) are subspp. Uncommon breeding resident. Nominate C. a. canescens of Sierra Nevada and Great Basin, subspecies, of which M. u. albescens is a synonym but some are C. a. collaris of Pacific Coast. No re- (Phillips et al. 1964), occurs mainly along Río Colo- cords of C. a. luteus, the Yellow-shafted Flicker of rado. Also locally west to Mexicali Valley from northeastern North America, but likely occurs as Mexicali (e.g., three 4 September 1995; SNGH) to rare fall and winter vagrant; C. a. borealis is a syn- Ejido Durango (e.g., two 31 December 1999; MAP) onym (Phillips et al. 1964). and along Río Hardy (e.g., 8 February 1905; ANSP 48289). M. u. cardonensis occurs around San Gilded Flicker Colaptes chrysoides subspp. C. c. Felipe and south and west from there. Claims of M. mearnsi was a former uncommon resident of Río u. cardonensis (as opposed to nominate subspecies) Colorado and upper Río Hardy (Grinnell 1928), but north to near California border (Grinnell 1928) is now nearly extirpated the length of lower Colo- should be verified. rado River (Rosenberg et al. 1991). Known from three records, all from Río Hardy 6 km southeast of Yellow-bellied Sapsucker Sphyrapicus varius. Benito Juárez 23–27 January 1928 (MVZ Casual winter vagrant. An adult male at Campo 52196-52198). Based on habitat and subspecies’ Mosqueda 29 December 1991–11 January 1992 fur- distribution, C. c. brunnescens of central Baja Cali- nished the second published record for Baja Califor- 49 fornia reaches southern tip of Colorado Desert at around ranchitos (e.g., near Colonias Progreso 17 northern limit of Pachycereus at Punta Radar (e.g., December 1994; RAE et al.). See Western Fly- two 25 March 2000; RAH et al.). Subspecies was catcher, below. previously known only south of ±30° N latitude, so Punta Radar would represent a major range exten- [Dusky Flycatcher Empidonax oberholseri]. Rare sion (for any Gilded Flicker). spring transient (mid-April–mid-May) through Salton Sea region, but no records for northeastern PASSERIFORMES Baja California. Tyrannidae Pacific-slope [Western] Flycatcher Empidonax Olive-sided Flycatcher Contopus cooperi subspp. difficilis difficilis. Fairlycommonspring Uncommon spring transient (late April–May). Of (mid-March–May) and fall transient (mid-August– note was an exceptionally late bird 11 km east of mid-October). A winter report from Río Hardy 2 Cerro Prieto 14 June 1928 (Grinnell 1928, MVZ February 1995 (Ruiz-C. and Rodríguez-M. 1997) is 52925). Based on specimens from southeastern in error—the photographs are of E. wrightii. Spe- California, nominate subspecies predominates, but cies limits versus the Cordilleran Flycatcher E.[d.] small numbers (<15%) are C. c. majorinus of occidentalis require more data (Phillips 1994). If montane southern California and northern Baja Cal- properly sexed, a female from Río Alamo ±40 km ifornia. One fall record, from Mexicali 1 September east of Mexicali (Seven Wells) 16 April 1894 2000 (RAE et al.). (USNM 133714) is E. d. [="o."] hellmayri (wing = 68.5 mm), but breeders do not arrive in southern Ar- Western Wood-Pewee Contopus sordidulus izona until 7 May (Phillips et al. 1964:88), so speci- subspp. Common spring transient (mid- men is apparently missexed (the measurements fit April–mid-June); fairly common fall transient male E. d. difficilis). (mid-August– mid-October). Based on specimens from Imperial Valley (SDNHM), both C. s. Black Phoebe Sayornis nigricans semiatra. Com- saturatus of Pacific Northwest and C. s. veliei of the mon winter visitor (mid-August–March); fairly Southwest occur as migrants, with the latter occur- common breeder, perhaps since mid-1950s because ring earlier during migration. considered only a winter visitor by Miller et al. (1957). Willow Flycatcher Empidonax traillii subspp. E. t. brewsteri of Pacific Northwest south through Si- Eastern Phoebe Sayornis phoebe. Casual winter erra Nevada is a common transient in spring vagrant. One record 18 km southwest of La Ventana (mid-May–mid-June) and fall (August–early Octo- 3–7 March 1998 (HG). ber). E. t. extimus breeds rarely along Río Colorado Say’s Phoebe Sayornis saya subspp. The northerly and formerly along Río Hardy, where five taken 11 nominate subspecies is a common winter visitor km east of Cerro Prieto 31 May–14 June 1928 (Unitt (mid-September–April); S. s. quiescens is an un- 1987, MVZ 52931–52935). common and local breeding resident. Hammond’s Flycatcher Empidonax hammondii. Vermilion Flycatcher Pyrocephalus rubinus Uncommontofairlycommonspringtransient flammeus. Rare to uncommon winter visitor (mid-March–mid-May). (mid-October–March). Formerly bred along Río Gray Flycatcher Empidonax wrightii. Uncom- Hardy; e.g., adult male and immature female 11 km mon transient in spring (mid-April–early May) and east of Cerro Prieto 28 May 1928 and 10 June 1928, fall (late August–early October); rare to uncommon respectively (Grinnell 1928, MVZ 52936, 52937; winter visitor (late November–late February), cf. Murphy 1917). Recently bred at Campo Río mainly in open desert scrub, but also occasionally Hardy, with pair present 20 March–21 August 1984 raising two young (REW). Adult males at mouth of 50

Río Hardy 27 August 1994 (Ruiz-C. and (1986:77) synonymized L. l. gambeli with L. l. Rodríguez-M. 1997, UABC 663) and Campo mexicanus, giving the latter an odd, disjunct range. Mosqueda 4 September 2000 (MAP) suggest con- Vireonidae tinued breeding along that drainage. Up to four at golf course along Río Nuevo in Mexicali 4–25 Au- Bell’s Vireo Vireo bellii arizonae. Former common gust 1990 (TEW et al.) suggest breeding in Mexicali breeder along Río Colorado; now nearly extirpated Valley. in lower Colorado River valley (Rosenberg et al. 1991). Presumed breeder along Río Hardy based on Ash-throated Flycatcher Myiarchus cinerascens. specimens from 11 km east of Cerro Prieto 2 and 12 Fairly common transient (mid-March–mid-May, June 1918 (Grinnell 1928, MVZ 53002, 53003) and mid-July–mid-October); uncommon to rare winter near Sierra Cucapah 5 April 1905 (USNM 197958). visitor; breeds at San Felipe (Huey 1927), in Only recent record is of singing male along Río low-elevation canyons in mountains (HG), and per - Hardy 20 March 1984 (REW, LRB). haps elsewhere (e.g., Río Hardy, Río Colorado). Species is monotypic, M. c. pertinax of Baja Cali- Gray Vireo Vireo vicinior. One record, of an adult fornia Sur being a synonym. male at San Felipe 12 April 1926 (Grinnell 1928, MVZ 48247). Attributed to most of northeastern [Brown-crested Flycatcher Myiarchus Baja California in winter (Bates 1992), but no evi- tyrannulus magister]. No records, but a potential dence it winters in region. Feeds almost exclusively breeder on Río Colorado, where apparently a recent on Bursera microphylla fruit during winter (Bates colonist (Rosenberg et al. 1991). 1992), so it may winter in Bursera scrub around San Eastern Kingbird Tyrannus tyrannus. Casual va- Felipe. Thus, whether the mid-April bird was a grant. One record, of one photographed at Laguna spring transient or overwintered is unknown. Salada 22 June 1997 (KAR; Figure 3- 9). [Plumbeous Vireo Vireo plumbeus plumbeus]. Cassin’s Kingbird Tyrannus vociferans. Casual No records, but presumably, at the least, a rare win- vagrant. One record, from Pozo Salado 6 April ter visitor (November–mid-March). 2000 (REW). Cassin’s Vireo Vireo cassinii cassinii. Uncommon Western Kingbird Tyrannus verticalis. Common spring transient (late March–mid-May). Probably a breeder (early March–September). rare fall transient, but no records. Laniidae Warbling Vireo Vireo gilvus swainsonii. Com- mon transient in spring (mid-March–May) and fall Loggerhead Shrike Lanius ludovicianus subspp. (late July–mid-October). Fairly common breeder; common winter visitor. Three subspecies occur as breeders, L. l. gambeli in Corvidae Mexicali Valley, L. l. excubitorides (of which L. l. American Crow Corvus brachyrhynchos nevadensis and L. l. sonoriensis are synonyms; Phil- hesperis. Presumably a rare to casual winter va- lips 1986) along Río Colorado (and probably west grant (October–April), but only one record, of six at into Mexicali Valley to some degree), and L. l. San Felipe 20 February 1997 (RP, KAR). Collected grinnelli in vicinity of San Felipe. Winter influx is in Valle de Río Colorado, Sonora, 14 March 1894 of L. l. excubitorides from Great Basin. Mexicali (van Rossem 1945). Claims of flocks on Río Colo- Valley breeders in past were mostly L. l. rado (Stone and Rhoads 1905) are doubtful. excubitorides (e.g., AMNH 439714, 10 km south of Mexicali 19 April 1915), but L. l. gambeli appears to Common Raven Corvus corax clarionensis. be displacing it in Salton Sink, where it now pre- Fairly common breeding resident. dominates even in Imperial Valley. Phillips 51

Alaudidae October). P. p. tachina is breeding subspecies; it and nominate subspecies account for migrants. One Horned Lark Eremophila alpestris subspp. Com- with rufous forehead in Mexicali Valley9 May 1997 mon winter visitor, mainly E. a. leucolaema of (SNGH) may have been P. p. melanogaster,of Rocky Mountains (Behle 1942) and E. a. which P. p. minima is a synonym (Phillips et al. ammophila of Mojave Desert (Miller et al. 1957). 1964). Forehead color is variable and partly E. a. leucansiptila, a Colorado Desert endemic, is a age-related (M. A. Patten pers. obs.), however, and fairly common breeding resident. P. p. melanogaster is unrecorded west of southeast- Hirundinidae ern Arizona and eastern Sonora.

[Purple Martin Progne subis subis]. No records, Barn Swallow Hirundo rustica erythrogaster. but presumably a rare spring transient Common transient in spring (mid-February–late (mid-April–mid-May), when recorded regularly on May) and fall (early July–early November). A few lower Colorado River (Rosenberg et al. 1991) and at may winter annually, but no records. Salton Sea. Remizidae Tree Swallow Tachycineta bicolor. Common tran- Verdin Auriparus flaviceps acaciarum. Common sient and winter visitor (early July–early May). breeding resident. Violet-green Swallow Tachycineta thalassina Sittidae thalassina. Fairly common spring transient (mid-February–April); uncommon fall transient [Red-breasted Nuthatch Sitta canadensis]. No (October). Breeders along cliffs above Laguna records, but a rare, nearly annual fall and winter vis- Salada near La Ventana, at least in wet years (e.g., itor to the Imperial Valley, so expected in the 50 pairs 20 March–23 April 1984; REW), might be Mexicali Valley. T. t. brachyptera of southern Baja California and Troglodytidae Sonora, but specimens are lacking. Birds breeding sparingly in lower Colorado River Valley might be Cactus Wren Campylorhynchus brunneicapillus intermediates between T. t. thalassina and T. t. anthonyi. Fairly common breeding resident. brachyptera (Phillips 1986:15), complicating the Subspecific taxonomy follows Rea and Weaver picture. T. t. lepida is a synonym of the nominate (1990). (Phillips 1986). Rock Wren Salpinctes obsoletus obsoletus.Un- Northern Rough-winged Swallow Stelgidopteryx common resident around San Felipe and in Sierra serripennis subspp. Common transient and breeder Cucapah. Rare winter visitor elsewhere (mid-February–early October). Uncommon winter (mid-October–mid-March). visitor. S. s. psammochrous is breeding subspecies, but most transients (and perhaps also wintering Canyon Wren Catherpes mexicanus conspersus. birds) are of northerly nominate subspecies Rare elevational visitor, wandering to lower eleva- (SDNHM). tions (<150 m) in rocky habitats, mainly during win- ter months (September–March). Bank Swallow Riparia riparia riparia. Uncom- montofairlycommontransientinspring(late Bewick’s Wren Thryomanes bewickii subspp. March–early May) and fall (early July–September). Fairly common winter visitor (mid-September– Reports from Río Hardy in February 1905 (Stone mid-April). Based on specimens from Imperial Val- and Rhoads 1905) are questionable. ley (SDNHM), most birds in Mexicali Valley are coastal T. b. charienturus, but a few (<5%) are Great Cliff Swallow Petrochelidon pyrrhonota subspp. Basin T. b. eremophilus. The latter is predominant Common transient and breeder (February–early 52 wintering subspecies on lower Colorado River 1957, REW, MAP). Birds on Río Colorado (Phillips et al. 1964). (SDNHM) are S. m. bairdi of interior Southwest, as presumably was sole record for Mexicali Valley, of House Wren Troglodytes aedon parkmanii.Un- 20 at Mexicali 14 December 1994 (TEW). Birds at common winter visitor (late August–April). San Felipe (SDNHM) are S. m. anabelae of Sierra Marsh Wren Cistothorus palustris subspp. C. p. Juárez and Sierra San Pedro Mártir. aestuarinus, with C. p. deserticola a synonym Mountain Bluebird Sialia currucoides. Presum- (Unitt et al. 1996), is a fairly common breeding resi- ably a rare, irregular winter visitor dent. Considering status in adjacent southern Cali- (mid-November– early March). Only two records, fornia (Unitt et al. 1996), winter numbers “several” 32 km southwest of Pilot Knob 29–31 augmented by both C. p. pulverius of Great Basin January 1928 (CCL) and a female 37 km south of El and C. p. plesius of interior Southwest. Miller et al. Mayor 20 February 1928 (Grinnell 1928, MVZ (1957) erroneously attributed C. p. paludicola of 52742). coastal Pacific Northwest to Río Colorado, but sub- species not recorded reliably even in California Swainson’s Thrush Catharus ustulatus subspp. (Unitt et al. 1996). Uncommon spring transient (May). Most migrants are nominate subspecies of Pacific Northwest, but Regulidae some C. u. oedicus of cismontane California may Ruby-crowned Kinglet Regulus calendula calen- occur. dula. Fairly common winter visitor (Octo- ber–April). Hermit Thrush Catharus guttatus subspp. Un- common transient and winter visitor (late Septem- Sylviidae ber–April). Based on status in Imperial Valley (SDNHM), most are nominate subspecies from in- Blue-gray Gnatcatcher Polioptila caerulea terior Alaska and adjacent Canada. C. g. nanus, obscura. Fairly common winter visitor (late Au- called C. g. osgoodi by Phillips (1991), of coastal gust–mid-May). P. c. amoenissima is a synonym southeastern Alaska and northwestern Canada pre- (Phillips 1991). sumably accounts for small percentage. A speci- Black-tailed Gnatcatcher Polioptila melanura men from San Felipe 12 April 1926 is C. g. sleveni lucida. Fairly common breeding resident. of central California coast (Grinnell 1928, MVZ 48388). C. g. sequoiensis of Sierra Nevada, some California Gnatcatcher Polioptila californica southern California mountains, and (subspecies pontilis. Uncommon resident near south end of presumed) Sierra San Pedro Mártir (Erickson and Bahía San Felipe, where sympatric with the Wurster 1998) might be a rare migrant, but unre- Black-tailed Gnatcatcher (RAH, SNGH et al.). corded in Colorado Desert. Specimens are lacking, but subspecies is presum- ably P. c. pontilis of central Baja California, the American Robin Turdus migratorius propinquus. northernmost taxon known to reach Gulf of Califor- Uncommon, irregular winter visitor (late Octo- nia (Atwood 1991, Mellink and Rea 1994). Subspe- ber–mid-April); sometimes fairly common (e.g., cies was previously known only south of ±30° N 30+ at Mexicali 14 December 1994; TEW). latitude, so Bahía San Felipe represents a major Mimidae range extension. Northern Mockingbird Mimus polyglottos Turdidae polyglottos. Common breeding resident. M. p. Western Bluebird Sialia mexicana subspp. Rare, leucopterus is a synonym (Phillips 1962). irregular winter visitor, mainly to Río Colorado (Grinnell 1928) and San Felipe (Huey 1927, A.O.U. 53

Sage Thrasher Oreoscoptes montanus. Uncom- (mid-August–mid-May). Most (±60%) are West montofairlycommonspringtransientCoast V. c. lutescens, followed by Great Basin V. c. (mid-January– March); presumably rarely winters orestera (±40%). Small numbers of V. c. celata of (mid-November–February). Alaska, northern Canada, and Northeast presum- ably move through during fall (October) and winter [Bendire’s Thrasher Toxostoma bendirei]. Ca- in small numbers. sual winter vagrant; one report, from Algodones 14 January 1988 (Daniels et al. 1993). Contrary to Nashville Warbler Vermivora ruficapilla claims by Wilbur (1987), the Algodones record was ridgwayi. Fairly common spring transient (late first potentially valid record for Baja California March–mid-May); uncommon to rare fall transient (Patten et al. 1993), though details probably not suf- (mid-August–early October). Casual in winter; two ficient to establish identification fully (Howell et al. records, from Mexicali 3 March 1999 (RAH) and 2001). Nelson (1922:126) attributed species to near Ejido Durango 31 December 1999 (MAP). northeastern Baja California without providing spe- cifics. Lucy’s Warbler Vermivora luciae. No recent re- cords, but presumed to be a fairly common breeder Crissal Thrasher Toxostoma crissale (late March–August) in extant riparian forest on Río coloradense. Uncommon breeding resident, Colorado (especially near Algodones). Casual else- mainly in mesquite thickets. where, with two adult males along Río Hardy 32 km southwest of Pilot Knob 15–16 March 1928 (MVZ Le Conte’s Thrasher Toxostomalecontei lecontei. 52536, 52537), where it probably bred formerly. Uncommon breeding resident, mainly in sandy, open desert scrub around San Felipe and Pattie Ba- Yellow Warbler Dendroica petechia subspp. sin (Murphy 1917, Grinnell 1928). Common transient (mid-April–May, August–Octo- ber), mainly D. p. morcomi, widespread in western Motacillidae North America and with D. p. brewsteri as a syn- American Pipit Anthus rubescens pacificus. onym. D. p. morcomi presumably augmented by Common winter visitor (October–early May). A. r. small numbers (<5%) of D. p. rubiginosa of Alaska, geophilus is a synonym. particularly in late spring and fall (but no records). An early male D. p. morcomi was 130 km south of Bombycillidae Mexicali 5 April 1915 (AMNH 440072). D. p. Cedar Waxwing Bombycilla cedrorum. Uncom- morcomi is probably regular in winter, but only one mon, irregular transient and winter visitor (Septem- record (subspecies presumed), from Mexicali 14 ber–mid-May). B. c. larifuga is not consistently December 1994 (TEW). D. p. sonorana of Arizona diagnosable (Mayr and Short 1970, Browning formerly bred on Río Colorado and upper Río 1990). Hardy (Grinnell 1928). Ptilogonatidae Yellow-rumped Warbler Dendroica coronata subspp. D. c. auduboni of Audubon’s Warbler sub- Phainopepla Phainopepla nitens lepida. Fairly species group is a common winter visitor common breeding resident in mesquite thickets (mid-September–early May). Fewer than 5% of laden with Phorodendron californicum; otherwise wintering birds are D. c. hooveri of the Myrtle War- common, with non-breeders in a variety of habitats bler subspecies group, with one a late bird at San late September–March. Felipe 10 May 1997 (RAH, SNGH). Parulidae Black-throated Gray Warbler Dendroica Orange-crowned Warbler Vermivora celata nigrescens. Fairly common spring transient (late subspp. Common transient and winter visitor March–mid-May); uncommon fall transient (Sep- 54 tember–October). An adult male on Río Colorado 2 Thraupidae March 1928 (MVZ 52560) and a bird at Campo Summer Tanager Piranga rubra subspp. P. r. Mosqueda 15 December 1994 (TEW) were presum- cooperi a former fairly common breeder in riparian ably wintering. forest along Río Hardy and Río Colorado (Grinnell Townsend’s Warbler Dendroica townsendi. 1928, Miller et al. 1957). P.r.rubra of eastern North Fairly common spring transient (mid-April–May); America probably occurs as a scarce fall and winter probably rare fall transient (late August–October), vagrant; e.g., female just west of Colorado Desert at but no records. Cañon Las Palmas 30 October 1957 (Miller et al. 1957, MVZ 52510). Only two recent records, fe- Hermit Warbler Dendroica occidentalis. Uncom- males along Río Hardy 23 April 1984 (REW) and at mon spring transient (mid-April–May). Campo Mosqueda 28 December 1996–19 February 1997 (KAR, RP), presumably were P. r. rubra. [American Redstart Setophaga ruticilla]. No re- cords, but presumably a rare winter visitor (Octo- Western Tanager Piranga ludoviciana. Common ber–mid-April), as small numbers winter annually transient in spring (mid-April–May) and fall in Imperial Valley (McCaskie 1970) and in lower (mid-July–October). An exceptionally early male Colorado River Valley (Rosenberg et al. 1991). was ±50 km north of San Felipe 30 March 1926 (Huey 1927). MacGillivray’s Warbler Oporornis tolmiei tolmiei. Fairly common transient in spring (late Emberizidae March–mid-May) and fall (late August–early Octo- Green-tailed Towhee Pipilo chlorurus. Rare tran- ber). sient and winter visitor (mid-September–early Common Yellowthroat Geothlypis trichas subspp. May). G. t. occidentalis, of which G. t. scirpicola of south- Spotted Towhee Pipilo maculatus subsp.? Pre- ern California and G. t. arizela of the Pacific North- sumed rare winter visitor (October–mid-April), but west are synonyms, is a common breeding resident. only two records, from Algodones 11 January 1990 Other populations of G. t. occidentalis augment (TEW) and 18 km southwest of La Ventana 21–22 breeding population during migration and winter. April 1998 (HG). Specimens from lower Colorado Wilson’s Warbler Wilsonia pusilla subspp. Based River valley are P. m. curtatus of western Great Ba- on status in Salton Sink (LACM, MVZ, SDNHM), sin (Grinnell and Miller 1944, Phillips et al. 1964), Pacific Coast W. p. chryseola a common transient in so it should account for most records. Near the re- spring (mid-March–May) and fall (mid-August– gion, P. m. megalonyx of cismontane southern Cali- October). One in winter, along Río Colorado south fornia has been collected in Imperial Valley(Cardiff of Algodones 14 January 1989 (TEW), was presum- 1956) and P.m. montanus of Great Basin and Rocky ably this subspecies. Small numbers (<10%) of mi- Mountains has nearly reached lower Colorado grants, particularly later in fall and spring, are likely River (Phillips et al. 1964). W. p. pileolata of Alaska and Great Basin. Nomi- Abert’s Towhee Pipilo aberti aberti. Common nate subspecies attributed, without specific data, to breeding resident. P. a. dumeticolus is a synonym Río Colorado (Miller et al. 1957); there are no re- (Phillips 1962). cords for southwestern North America. Chipping Sparrow Spizella passerina subspp. Yellow-breasted Chat Icteria virens auricollis. Uncommon winter visitor (mid-September–April). Uncommon breeder (mid-April–mid-September) S. p. arizonae, a widespread breeder in western on Río Colorado and Río Hardy. Rare transient North America, probably accounts for vast majority elsewhere in both spring (late April–mid-May) and (>95%) of records, but S. p. boreophila of Alaska fall (September). 55 and boreal Canada has been taken in Imperial Valley (MVZ 52370). One from San Felipe 11 April 1926 and S. p. passerina of eastern North America has is P. s. brooksi of coastal Pacific Northwest been taken on lower Colorado River (Phillips et al. (Grinnell 1928, MVZ 48112). P.s. rostratus breeds 1964), so occasional individuals may be these sub- commonly around Río Colorado delta, perhaps species. south to San Felipe (Miller et al. 1957), with iso- lated breeding inland at Campo Geotérmico Cerro Brewer’s Sparrow Spizella breweri breweri. Prieto (Molina and Garrett 2001). It winters Common winter visitor (early September–April). (mid-July–mid-February) in various portions of Vesper Sparrow Pooecetes gramineus confinis. northeastern Baja California, including sparingly in Uncommon winter visitor (late September–March). agricultural fields (e.g., near Algodones 29 Decem- ber 1991; MAP et al.), but is threatened and declin- Lark Sparrow Chondestes grammacus strigatus. ing (Mellink and Ferreira-B. 2000). Fairly common winter visitor (late Septem- ber–April). Breeding began in the Imperial Valley Grasshopper Sparrow Ammodramus in mid-1980s and might now occur in Mexicali Val- savannarum perpallidus. Casual winter vagrant. ley. One record, from 18 km southwest of La Ventana 20 December 1997 (HG). Only A. s. perpallidus, wide- Black-throated Sparrow Amphispiza bilineata spread in western North America, has been re- deserticola. Uncommon to fairly common breeding corded in California and Baja California. resident, in moderately dense desert scrub near and above sea level, as at Sierra Cucapah (Stone and Fox Sparrow Passerella iliaca schistacea. Casual Rhoads 1905), Sierra las Pintas (HG), and San winter visitor. Two records, of a male along Río Al- Felipe (REW, MAP). amo 32 km southwest of Pilot Knob 28–31 January 1928 (Grinnell 1928, MVZ 52470, CCL) and a fe- Sage Sparrow Amphispiza belli nevadensis. male at Mexicali 1 February 1929 (UMMZ Fairly common winter visitor (late Septem- 167282). ber–mid-April) from Mojave Desert and Great Ba- sin. Includes as synonyms A. b. canescens and A. b. [Swamp Sparrow Melospiza georgiana campicola (Patten and Unitt 2001). ericrypta]. No records, but presumably a rare win- ter visitor (November–March) given its status in Lark Bunting Calamospiza melanocorys. Rare to Imperial Valley and on lower Colorado River casual winter and spring vagrant (November–early (Rosenberg et al. 1991), including one on east bank May) to Salton Sea, but only three records for north- of Río Colorado near Moctezuma, Sonora, 31 De- eastern Baja California, a male ±50 km north of San cember 1999 (MAP) within 50 m of Baja California Felipe 22 March 1926 (Huey 1927), a small flock border. near San Felipe 4 April 1926 (Huey 1927), and ≤ 200 (including singing males) near San Felipe 19 Song Sparrow Melospiza melodia subspp. M. m. March–23 April 1984 (REW, LRB). Mistakenly fallax, of which M. m. saltonis is a synonym (Patten called “common throughout [Baja California] in 2001), is a common breeding resident in riparian winter” by Miller et al. (1957). thickets throughout, but especially along Río Colo- rado and Río Hardy. Small numbers of M. m. Savannah Sparrow Passerculus sandwichensis montana, which includes M. m. fisherella (Patten subspp. P.s. nevadensis of the Great Basin is a com- 2001) of northern Great Basin, winter regularly on mon winter visitor (mid-August–mid-May). Based lower Colorado River (Grinnell and Miller 1944, on status in Salton Sink (MVZ, SDNHM), small Phillips et al. 1964). A few M. m. heermanni, with numbers (<5%) of wintering birds are P. s. anthinus M. m. cooperi a synonym (Patten 2001), of of Alaska and adjacent Canada, including one from cismontane central and southern California reach 32 km southwest of Pilot Knob 26 January 1923 Imperial Valley each winter. It presumably occurs 56 occasionally, at least in Mexicali Valley, and has of the longspurs should be basal to the emberizid ra- been “recorded from east base of Sierra San Pedro diation (Patten and Fugate 1998). Mártir” (Miller et al. 1957). [Lapland Longspur Calcarius lapponicus Lincoln’s Sparrow Melospiza lincolnii subspp. alascensis]. No records, but probably a casual win- Nominate subspecies, with M. l. alticola a syn- ter visitor given status in adjacent Imperial Valley. onym, is a fairly common winter visitor (late Sep- tember–mid-April). M. l. gracilis of southeastern Chestnut-collared Longspur Calcarius ornatus. Alaska and coastal British Columbia has reached Casual winter visitor. One record, a flock of up to 50 lower Colorado River (Grinnell and Miller 1944, south of Algodones 12–16 November 1994 (TEW, Phillips et al. 1964) and Imperial Valley (SDNHM), KAR). so probably occurs sparingly. Cardinalidae White-crowned Sparrow Zonotrichia leucophrys Black-headed Grosbeak Pheuticus subspp. Common winter visitor (mid-September– melanocephalus maculatus. Common spring tran- mid-May), predominantly Z. l. gambelii of Alaska sient (April–May); uncommon fall transient (Au- and adjacent Canada. Small numbers are Z. l. gust–mid-October). oriantha of montane West, mainly during migration (September–October, late April–May). Blue Grosbeak Guiraca [Passerina] caerulea salicaria. Fairly common breeder (mid-April–early Golden-crowned Sparrow Zonotrichia October). Merging of Guiraca into Passerina rec- atricapilla. Presumed to be a rare winter visitor ommended by various authorities (Phillips et al. (November–early April), but only two records, 1964, Mayr and Short 1970, Unitt 1984, Howell and from south of Algodones 12 November 1994 Webb 1995). Contrary to A.O.U. (1957) and Miller (TEW) and Mexicali 28 December 1996 (KAR). et al. (1957), P.c. interfusa of interior Southwest has not reached lower Colorado River Valley (van Dark-eyed Junco Junco hyemalis subspp. Rare Rossem 1945, Phillips et al. 1964). winter visitor (October–March). Based on speci- mens from Imperial Valley and lower Colorado Lazuli Bunting Passerina amoena. Fairly com- River (SDNHM), over 90% are two subspecies in mon to uncommon transient in spring (April–May) the Oregon Junco complex, J. h. montanus of north- and fall (August–September). ern Great Basin, the most numerous, and J. h. thurberi of montane California. Most of remainder [Indigo Bunting Passerina cyanea]. No records, are in the Slate-colored Junco complex (e.g., Sierra but regular on lower Colorado River (Rosenberg et Cucapah 24 February 1905; ANSP 48366), both J. al. 1991) and recorded seven times around Salton h. cismontanus of Canadian Rocky Mountains and Sea. Also one of the more common “eastern” birds nominate subspecies of eastern North America, recorded in southern California (Garrett and Dunn with the former accounting for >90% of records. No 1981). records of the Gray-headed Junco J. h. caniceps or Icteridae Pink-sided Junco J. h. mearnsi, but each probably occurs as each is annual (or nearly so) at Imperial Red-winged Blackbird Agelaius phoeniceus Valley and lower Colorado River Valley (Phillips et sonorensis. Common breeding resident, with num- al. 1964, MAP). bers augmented in winter. A. p. neutralis of south- ern Pacific Coast has reached Imperial Valley [McCown’s Longspur Calcarius mccownii]. No (Grinnell and Miller 1944, MVZ 8205) and Arizona records, but probably a casual winter visitor, as in (Phillips et al. 1964, Rea 1983), so it may occur on adjacent Imperial Valley. Phyologenetic placement occasion. 57

Western Meadowlark Sturnella neglecta cord, 18 km southwest of La Ventana 16–17 neglecta. Fairly common breeding resident; com- December 1997 (HG). mon winter visitor (October–March). Bullock’s Oriole Icterus bullockii. Common Yellow-headed Blackbird Xanthocephalus breeder (mid-March–September). With species sta- xanthocephalus. Uncommon breeder (Grinnell tus of Black-backed Oriole I. abeillei (A.O.U. 1928, Howell and Pyle 1990, Howell and Webb 1998), Bullock’s Oriole is monotypic, neither I. b. 1992); fairly common to common winter visitor parvus nor I. b. eleutherus being diagnosable. (October–April). Scott’s Oriole Icterus parisorum. Uncommon Brewer’s Blackbird Euphagus cyanocephalus breeder around San Felipe (Huey 1927, MVZ minusculus. Common winter visitor (Octo- 48060, 48061). Has occurred in spring (May 1997, ber–March). Breeding began in Imperial Valley, April 1998) in Sierra las Pintas (HG). Rare winter south to El Centro, in the past 15 years, so it may visitor, mainly around San Felipe (e.g., 23 February breed in Mexicali Valley. Late birds at the Río 1998; RAE et al.). An 8 January 1982 male listed at Hardy 22 April 1995 and 28 May 1994 (Ruiz-C. and “San Felipe” by Wilbur (1987) was actually ±24 km Rodríguez-M. 1997) were either summering or north of that town (DES). breeding. Fringillidae Great-tailed Grackle Quiscalus mexicanus [Purple Finch Carpodacus purpureus subspp. Common breeding resident in the Mexicali californicus]. No records, but presumably a rare, Valleyand along the Río Colorado. This species has irregular winter visitor (September–mid-April). not really extended south beyond the limits of agri- cultural development in the region. Q. m. nelsoni of House Finch Carpodacus mexicanus frontalis. Sonora was the first to colonize southeastern Cali- Common breeding resident. fornia (beginning in 1964, breeding by 1968) and thus presumably northeastern Baja California. Q. Pine Siskin Carduelis pinus pinus. Presumably a m. monsoni of Chihuahua and southeastern Arizona rare and irregular winter visitor (Novem- reached southeastern California in mid-1980s and ber–March). Four records, the first of “2 or 3 probably also occurs in adjacent Baja California. It flocks” at Río Alamo 32 km southwest of Pilot may displace the smaller Q. m. nelsoni (Rea 1969, Knob 21–31 January 1928 (CCL), including an W. Wehtje pers. comm.). adult male collected (Grinnell 1928, MVZ 52358). Individuals were 10 km south of Algodones 29 De- Bronzed Cowbird Molothrus aeneus loyei. Rare cember 1991 (Patten et al. 1993) and 12 November presumed breeder (mid-April–early September), 1994 (TEW) and at Río Hardy 3 February 1995 with records from Algodones (including six birds 9 (Ruiz-C. and Rodríguez-M. 1997). July 1995; KAR), Benito Juárez (SNGH et al.), and Mexicali (KLG). A recent colonist. Lesser Goldfinch Carduelis psaltria psaltria. Fairly common winter visitor (September–April); Brown-headed Cowbird Molothrus ater subspp. presumed uncommon breeder given status in Impe- M. a. obscurus is a common breeding resident. rial Valley. Taxonomy follows Phillips et al. (1964). Winter numbers are augmented by M. a. artemisiae of Great Basin. Lawrence’s Goldfinch Carduelis lawrencei. Given its status on lower Colorado River Hooded Oriole Icterus cucullatus nelsoni.Un- (Rosenberg et al. 1991) and around Salton Sea, pre- common breeder (mid-March–mid-September), sumably a rare spring transient (late Febru- but local (most breeders use Washingtonia palms), ary–April) and casual winter visitor (Miller et al. so generally only in settled areas. One winter re- 1957); has bred. Only records are of three in Sierra 58

Cucapah 25 February 1905 (Stone and Rhoads troduced into Mexicali Valley were in P. c . 1905, ANSP 48359–48361), six along Río Hardy 20 torquatus subspecies complex from central and March 1984 (REW, LRB), and nesting at 150 m ele- eastern Asia (Leopold 1959). Some birds recently vation in Sierra las Pintas in March 1998 (HG). taken by hunters are hybrids between that complex Also a probable sight record along Río Hardy 30 and apparent P. c. principalis/chrysomelas subspe- March 1917 (Murphy 1917). cies complex of Afghanistan (Cramp and Simmons 1979), introduced along lower Colorado River American Goldfinch Carduelis tristis salicamans. (Brown 1989) and presumably reaching Baja Cali- Presumably a rare winter visitor (mid-November– fornia. April) based on its status in adjacent Imperial Val- ley, but only two records, of a “very few” at Rock Dove [Feral Pigeon] Columba livia. Com- Mexicali 19 February 1990 (ENA, DK) and a fe- mon breeding resident. Use of the name “Feral Pi- male 18 km southwest of La Ventana 18 December geon” rather than “Rock Dove” for introduced, 1997 (HG). highly human-modified populations was advocated by Howell and Webb (1995) and Patten et al. (in NON-NATIVE SPECIES press). Ring-necked Pheasant Phasianus colchicus subspp. Fairly common resident in Mexicali Valley European Starling Sturnus vulgaris. Common (Leopold 1959, Patten et al. 1993), although its es- breeding resident, presumably first reaching area in tablishment is disputed (Howell and Webb late 1950s (see Cardiff 1961). 1995:768) despite records of up to 20 birds on 25+ House Sparrow Passer domesticus. Common occasions from mid-1980s to present (TEW, MAP breeding resident that probably reached Mexicali et al.). Definitely breeds at Colonias Progreso, Valley by the early 1910s (based on records in adja- Carranza, and Bórquez (J.M. Pereyra pers. comm.), cent Imperial Valley). Established throughout, even mostly in vegetated drains and asparagus fields. in more “natural” habitats such as marshes and ri- Also a sizable breeding population on Río Colorado parian along rivers. south of Yuma (Brown 1989). Birds originally in-

ACKNOWLEDGMENTS

George F. Barrowclough and Christine Blake reviewed at the Museum of VertebrateZoology. Pat- (American Museum of Natural History), Louis R. ten’s specimen work was partly funded by a grant Bevier and Nate Rice (Academy of Natural Sci- from the American Museum of Natural History. ences, Philadelphia), René Corado (Western Foun- Gómez de Silva’s fieldwork in Sierra Las Pintas was dation of Vertebrate Zoology), Carla Cicero and supported by grants from Lincoln Park Zoo’s Scott Jason A. Mobley (Museum of Vertebrate Zoology), Neotropic Fund, Fondo Mexicano para la Charles M. Dardia (Cornell University), James P. Conservación de la Naturaleza, A.C., and Programa Dean and Craig Ludwig (National Museum of Nat- de Apoyo de la División de Estudios de Posgrado, ural History), Kimball L. Garrett (Natural History Universidad Nacional Autónoma de México. Museum of Los Angeles County), John C. Hafner Compañía San Felipe, S.A. de C.V provided logisti- (Moore Laboratory of Zoology, Occidental Col- cal and in-kind support for this fieldwork. Eugene lege), Fritz Hertel (Dickey Collection), Janet N. Anderson, Richard A. Erickson, Kimball L. Hinshaw (University of Michigan Museum of Zool- Garrett, Robert A. Hamilton, Osvel ogy), and David Willard (Field Museum of Natural Hinojosa-Huerta, Steve N.G. Howell, Kathy C. History) provided data about specimens in their Molina, Eduardo Palacios, J.M. Pereyra, Peter Pyle, care. Portions of Chester C. Lamb’s field notes were Kurt A. Radamaker, Donald E. Schmoldt, Brenda 59

D. Smith, Paul F. Springer, Philip Unitt, Richard E. Eduardo Palacios, Scott B. Terrill, and Richard E. Webster, and Walter Wehtje supplied copies of field Webster for their careful reviews of the manuscript. notes and/or other unpublished data. Lastly, we thank Kenneth P. Able, Jon L. Dunn, Richard A. Erickson, Kimball L. Garrett, Steve N.G. Howell,

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Birds of the Baja California Peninsula: Status, Distribution, and Taxonomy (R.A. Erickson and S.N.G. Howell, eds.). Monographs in Field Ornithol. No. 3. Amer. Birding Assoc., Colorado Springs, Colorado; ISBN: 1-878788-39-6; Library of Congress Control Number: 2001098455; Avail- able from ABA Sales, PO Box 6599, Colorado Springs, CO 80934, 800/634-7736, www.americanbirding.org.