This checklist (<- click to download .pdf file) is an update of checklists prepared previously by Howell et al. (2001) and Erickson et al. (2013). The conventions used follow closely upon those in the previous edition, but we have excluded numerous taxonomic notes included there. We follow AOS (2020) taxonomy and have continued to include subspecific groups at our discretion, including all groups considered species by Navarro-Sigüenza and Peterson (2004). A summary and analysis of these checklists is included in the Discussion section of the main text. Note that this list makes use of observations through the summer of 2020.


We abbreviate Baja California as BC and Baja California Sur as BCS. North American Birds journal is abbreviated as NAB. Museum abbreviations are listed at the beginning of the main text.

1 species mentioned in main text, figures, or tables
2 annotations in footnotes below

Abundance Codes

c common
u uncommon
r rare, but annual or nearly so
vr very rare: less than annual but more than five records
x accidental: five or fewer records
H of hypothetical occurrence; note that most discussions of hypothetical species by Grinnell (1928), Wilbur (1987), Howell et al. (2001), and Erickson et al. (2013) are not repeated here

Seasonal Codes

R confirmed or presumed breeding resident
S breeding summer visitor
W winter visitor
T transient migrant in spring and fall
Sp spring transient migrant; depending upon the species involved, this period may begin as early as January or end as late as July
F fall transient migrant; depending upon the species involved, this period may begin as early as June or end as late as December
V non-breeding visitor; present up to all year (mainly seabirds)

[] use of brackets indicates former status, generally >50 years ago for species now considered historical only, but may be as few as 10 years for declining species

Breeding Codes

* confirmed breeding species: nests, eggs, dependent young (except some waterbirds, e.g., begging juvenile terns which may travel with adults for hundreds of km), adults nest building (except woodpeckers, wrens, and Verdin, which may drill/build roost nests), adult(s) carrying food/fecal sac, adults entering nest cavity, birds collected in breeding condition by reliable collectors (cf. Binford 1989:68)

*? probable breeding: adult(s) singing, courting, displaying, territorial, and/or agitated as if nest and/or young nearby, in season, and in range/habitat

+ possible breeding: adult(s) in season in range/habitat

() irregular and/or former (confirmed, probable, or possible) breeding, e.g., waterbirds dependent on ephemeral water conditions

[] former (confirmed, probable, or possible) breeding, i.e., species considered extirpated or extinct

Documentation Codes

# specimen record, including eggs
PP identifiable photographic record published, includes stills captured from video
SoP sonogram published
A! audio recording archived
SP sight record published with adequate supporting documentation
S! sight record; written documentation archived (cf. Hamilton and Howell 2001, Erickson et al. 2008)
S unqualified sight record


Black-bellied Whistling-Duck. A specimen reportedly taken at Los Robles, Baja California, 21 August 1897 by William W. Price (CUMV 260) was discussed by Erickson et al. (2001) and considered to be of uncertain provenance. We now know that the specimen was not taken in Mexico by Price himself, as he was actively collecting mammals in El Dorado County, California during the entire month of August 1897, attested to by numerous specimens of his at the California Academy of Sciences. Price collected widely in California and Arizona but appears to have made only one trip to Mexico, in the vicinity of the Colorado River delta in 1898 (Price 1899, Fisher 1923; cf. Grinnell 1928). Price did sponsor a collecting trip by Loye Miller and others to the Cape District in the spring and summer of 1896 (Fisher 1923), as amusingly recounted by Miller (1950). Someone may yet discover the actual story behind the specimen, but for now we are unaware of any other specimens from “Los Robles, Baja California,” in 1897 or otherwise.

Fulvous Whistling-Duck. Last BC record: 1958 (Banks 1967).

“Lesser” Canada Goose. The validity of this taxon “has come into question of late. It is probably not monotypic, but rather a dumping ground for smaller bodied populations of Canada Goose (or perhaps, Canada x Cackling Geese)” (S. G. Mlodinow pers. comm.).

Tundra Swan. Last reported in BC in the late 1990s (Unitt et al. 1995, Wurster et al. 2001; Antonio Simental, Rancho Japá resident, pers. comm. to RAE).

White-winged Scoter. Contra Erickson et al. (2013), correct citation for BC photo is NAB 63:327.

Long-tailed Duck. First reported in BCS in 1983 (Howell et al. 2001), photo-documented in 2014 (NAB 69:296-297).

Band-tailed Pigeon. BCS record of P. f. monilis discussed in NAB 69:297.

Inca Dove. 2015 BCS photo in NAB 70:235.

Black Swift. Now considered documented by sight records only, as the BC specimen alluded to by Anthony (1893) cannot be found.

“Sedentary” Allen’s Hummingbird. Nesting beginning in 2014 documented by Erickson (2016).

Mountain Plover. Last BCS record: 1925 (Lamb 1927).

Snowy Plover. D’Urban Jackson et al. (2020) discussed population differentiation on the peninsula and elsewhere.

Upland Sandpiper. One record: 2014 (NAB 68:431).

Bar-tailed Godwit. Grinnell (1928) described in some detail the tale of a bird collected at La Paz, BCS in the winter of 1882-1883 (USNM 86418) and identified as this species by Robert Ridgway (Belding 1883). Only the head of the bird remained at the time of Grinnell’s review, making identification difficult. As a result, Grinnell and all subsequent reviewers have considered the record hypothetical. We suspect some motivated ornithologist will eventually use modern techniques to confirm the original identification of the specimen, thus establishing one of the earliest records of the species in North America.

Sharp-tailed Sandpiper. One record, the only one for Mexico: 2015 (NAB 70:123).

Semipalmated Sandpiper. BC photo: 2016 (NAB 70:392).

Parakeet Auklet. For his upcoming guide to the birds of Mexico, S. N. G. Howell (pers. comm.) reviewed all reports of species reported only a few times in Mexico and found the sole report of this species not thoroughly convincing. We follow his lead in considering the species’ occurrence in BC only hypothetical at this time.

Crested Auklet. One record: 1980 (Pitman et al. 1983).

Arctic Tern. Howell et al. (2001) and Erickson et al. (2013) were unaware of BC specimens, but at least three have been attributed to Mexican waters along the U.S. border where international maritime boundaries have not always been well understood. These boundaries are established by nearest point of land (including islands) rather than latitudinal lines based on mainland boundaries. All three specimens were taken by J. R. Jehl, Jr. and J. W. Hardy on 3 Sep 1967. One (MLZ 65783) is attributed to the Sixty Mile Bank, which is now well established as being in American waters. The labels on the other specimens (SDNHM 36127, 36128) are for “50 miles [presumably nautical miles] west southwest of San Diego.” This location is closer to San Diego, but farther from San Clemente Island, and actually closest to the Mexican mainland. The precise location where any of these specimens was taken is unknown, but we are willing to lay claim to at least the SDNHM specimens as being of Mexican origin.

Red-tailed Tropicbird. One record: 1897 (Anthony 1898), but probably regular over far offshore waters.

Red-throated Loon. 2014 BCS photo in NAB 68:279.

Arctic Loon. One record: 1998 (Erickson et al. 2001).

Short-tailed Albatross. Last BCS record: 1888 (Bryant 1889).

Wedge-rumped Storm-Petrel. Last BC record: 1950 (Huey 1952).

Guadalupe Storm-Petrel. Last record: 1912 (Jehl and Everett 1985).

Kermadec Petrel. Several reports (1993-2015) summarized by Martínez Damián et al. (2015) and in NAB 70:122.

White-necked Petrel. One record: 2014 (Dunn 2015).

Bulwer’s Petrel. S. N. G. Howell (pers. comm.; Howell and Webb 1995) reviewed all reports of species reported only a few times in Mexico and found the sole BCS report of this species not thoroughly convincing. We follow his lead in considering the species’ occurrence in BCS only hypothetical at this time.

Buller’s Shearwater. BC specimen: 2013 (UABC 1958, NAB 68:153).

Manx Shearwater. One BCS record: 2015 (NAB 69:497).

Pelagic Cormorant. 2020 BCS photo in Figure 46.

Brown Pelican. Anderson et al. (2013) prepared a thorough analysis of population size in our area (Figure 47).

American Bittern. Last suspected BC nesting: 1893 (Anthony 1893).

Roseate Spoonbill. Last BC record: 1915 (Grinnell 1928).

Swallow-tailed Kite. One record: 2013 (NAB 67:521).

Sharp-shinned Hawk. Last summer record: Sierra San Pedro Mártir, 1977 (Wilbur 1987).

Bald Eagle. Last known BC nesting: 1924 (WFVZ 83452, Grinnell 1928).

Common Black Hawk. We consider the following to be the first two records for BCS: Estero San José 26 Dec 1994 (Sandy Williams in litt.) and Lagunas de Chametla 23 Jan 2004 (†Phillip J. Capitolo et al.; previously treated as hypothetical by Erickson et al. 2013).

Rough-legged Hawk. One record: 1962 (Erickson et al. 2001).

Northern Pygmy-Owl. The nest of the endemic Cape Pygmy-Owl (G. g. hoskinsii) remains undescribed.

Elf Owl. Last BC record: 1947 (Banks 1967).

Spotted Owl. Last record: 1972 (Wilbur 1987).

Red-breasted Sapsucker. Reports from BCS and s. BC would benefit from review and consistent treatment with current identification criteria in mind.

“Guadalupe” Northern Flicker. Last record: 1906 (Greenway 1967, Sweet et al. 2001).

Crested Caracara. Last known BC nesting: 1926 (Wilbur 1987).

Guadalupe Caracara. Last record: 1900 (Abbott 1933).

Great Kiskadee. One record: 1987 (Collins et al. 1990).

Thick-billed Kingbird. One BC record: 1995 (Erickson et al. 2001).

Alder Flycatcher. One record: 1911 (Howell et al. 2001).

Willow Flycatcher. Last known nesting: 1925 (Unitt 1987).

Steller’s Jay. Last record: 1885 (Erickson et al. 2013).

Clark’s Nutcracker. Last BCS record: 1996 (Erickson et al. 2013).

Barn Swallow. Recent nesting: 2014 (NAB 68:556-557).

Cave Swallow. One record: 2013 (NAB 68:154).

Red-breasted Nuthatch. Last record of nesting population on I. Guadalupe: 1971 (Jehl and Everett 1985, Quintana-Barrios et al. 2006).

Bewick’s Wren. Last record of endemic I. Guadalupe subspecies T. b. brevicauda: 1892 (Grinnell 1928, Greenway 1967).

“Guadalupe” Ruby-crowned Kinglet. Last record: 1953 (Jehl and Everett 1985, Quintana-Barrios et al. 2006).

Dusky Warbler. Last record: 1995 (Erickson et al. 2001).

Arctic/Kamchatka Leaf Warbler. Following the AOU’s formal split of the Arctic Warbler into three species (Chesser et al. 2014), the single peninsular record (Pyle and Howell 1993) is now considered equivocal, as discussed by Erickson et al. (2013).

Swainson’s Thrush. We now consider records of the “Olive-backed Thrush” to be hypothetical. Grinnell (1928) listed a single specimen of C. u. swainsoni for each state but Ramos (1991) could not find them and considered the reports dubious. The whereabouts of the specimen collected by Lamb (1925) at La Paz are unknown but the particulars of a specimen listed in VertNet as C. u. oedicus (i.e., “Russet-backed Thrush”) (MVZ 47683) match those given by Grinnell for the BC specimen.

Eastern Yellow Wagtail. One record, the only one for Mexico: 1997 (Erickson et al. 2001).

American Pipit. Last summer record: Sierra San Pedro Mártir, 1991 (Howell and Webb 1992). Reports of the subspecies japonicus would benefit from review and consistent treatment with current identification criteria in mind.

Sprague’s Pipit. BC photo: 2015 (NAB 70:123).

“San Benito” House Finch. Last record: 1938 (Jehl 1971).

Purple Finch. Last suspected nesting: 1924 (Huey 1926, Erickson et al. 2013).

Red Crossbill. There has been upheaval in crossbill taxonomy in recent decades with most emphasis now on vocalizations (Benkman and Young 2020). To our knowledge, to date all recordings from our area have been Type 2. Last record of possible resident population on I. Guadalupe: 1897 (Grinnell 1928, Jehl and Everett 1985).

Lapland Longspur. Last BCS record: 1997 (Erickson et al. 2001).

Harris’s Sparrow. Last record: 1995 (Erickson et al. 2001).

Song Sparrow. The subspecific status of resident birds in the mid-peninsula is in need of clarification. The endemic “Brown’s” Song Sparrow (M. m. rivularis; fallax group) has long been known from n. BCS (San Ignacio) southward and the n. subspecies heermanni (samuelis group) has more recently been found south into the Vizcaíno Desert as far as Arroyo Santo Dominguito in sw. BC, but specimens do not exist from this area. Lone birds seen farther south have also been identified as heermanni: Villa Jesús María 11 Nov 2011 (NAB 66:176) and Guerrero Negro 16 May-1 Jun 2011 (NAB 65:522, 524; Erickson et al. 2013). Three Song Sparrows in apparently suitable habitat on the n. side of the Sierra de San Francisco 18 Mar 2016 (Andrew Emlen et al.) extend the range of presumed rivularis approximately 40 km north of San Ignacio.

“California” Song Sparrow. Last record of insular M. m. graminea on Is. Coronado: 1977 (Jehl 1977) and now believed to be extirpated (Everett 1992, Erickson et al. 2010).

Rufous-crowned Sparrow. Last record of endemic Is. Todos Santos subspecies A. r. sanctorum: 1938 (UMMZ 95703, Wilbur 1987, Samaniego Herrera et al. 2007). Grinnell (1928) did not recognize Todos Santos birds as distinct and Cogswell (1968) seems to have questioned the validity of the subspecies, if only offhandedly.

Spotted Towhee. Last record of endemic I. Guadalupe subspecies P. m. consobrinus: 1897 (Grinnell 1928, Greenway 1967).

Tricolored Blackbird. Erickson et al. (in review) summarized all records of the species in BC and predicted its imminent demise in Mexico.

Louisiana Waterthrush. Last BC record: 1996 (Erickson et al. 2001).

Golden-winged Warbler. One record each: BC (1991, Howell and Pyle 1993), BCS (1996, Erickson et al. 2001).

Lucy’s Warbler. Last probable nesting record: 1928 (Grinnell 1928).

Connecticut Warbler. One BCS record: 1999 (Erickson et al. 2001).

Kentucky Warbler. One BCS record: 1999 (Erickson et al. 2001).

Fan-tailed Warbler. One record: 1925 (Grinnell and Lamb 1927).

Red-faced Warbler. One at Cerro Guayparín Grande in the Sierra de La Laguna 3-4 Feb 1985 has not been published previously and represents the only record of this distinctive species in our area. Shari Kearney wrote in eBird that “The red-faced warbler was in a mixed flock [of] 5 to 6 species and approximately 50 individuals. I saw the warbler on 2 successive days. The mixed flock was moving along a ridge crest (1400 meters) when I saw [it and it was] in my vicinity for 10 to 15 minutes. I got a very good look at this warbler on both days: red headed and faced with a black crown much like scarf tied over its head, gray body.”

Painted Redstart. Shari Kearney also reported this species in eBird. One at 1700 m on Picacho del Diablo in the Sierra San Pedro Mártir, BC 1 Dec 1984 was seen prior to all other records.

Summer Tanager. Last nesting record: 1928 (Grinnell 1928, Howell et al. 2001).

Spotted Dove. Possibly extirpated; last reported in September 2015.