Erickson, R. A., G. Marrón, and E. D. Zamora-Hernández. 2022. Year 2021: Baja California Peninsula. <https://wp.me/p8iY2g-dqW> North American Birds.
This is our second annual report for the Baja California Peninsula. The number of species recorded was up (405 compared to 402 in 2020), with an impressive increase in Baja California (380 vs. 360) but a decrease in Baja California Sur (316 vs. 336); reports of pelagic species were especially lacking in Baja California Sur (Table 1). The only addition to the regional (and Mexican) list was the exotic Swinhoe’s White-eye, although Arctic Warbler was confirmed in Baja California Sur (replacing Arctic/Kamchatka Leaf Warbler on the Mexican list). First state records were of Chimney Swift in Baja California and Allen’s Hummingbird and White-throated Sparrow in Baja California Sur. Second state records were established by Thick-billed Kingbird, Streak-backed Oriole, and Mourning Warbler in Baja California and Kentucky Warbler in Baja California Sur. Other top rarities were Hudsonian Godwit, the continuing Great Kiskadee, Nelson’s Sparrow, and a returning Townsend’s x Black-throated Green Warbler. White-faced Ibis was found nesting in Baja California Sur for the first time; Elf Owl was documented in Baja California for the first time in more than 70 years; and Broad-winged Hawk was new in spring, Belted Kingfisher in summer. Compared to the last two years, Clark’s Nutcracker and Red Crossbill numbers were way down in the mountains, but the number of vagrant warbler species recorded was the highest in 20 years.
With the continued dominance of eBird in North America, and the easy and intuitive access to its bird distribution data, we are comfortable easing our approach to presenting specific localities, dates, and listing individual records. I.e., we will write our reports less specific in nature, knowing that interested readers can easily expand their understanding by consulting eBird records on their own. Important information not obtained from eBird will continue to be presented in greater detail. A general discussion of our approach to report preparation and recommendations for contributors was included in the introduction to our 2020 report, which we refer readers to now.
Mexican municipios (comparable to counties) were added to eBird’s analysis and data presentation capabilities in 2021. In response, we prepared an initial table of all species recorded in each of the region’s 11 municipios. The table is included at the end of this report and we encourage readers to consult it and assist us in making future versions more complete.
Table 1. Summary of naturally occurring species recorded in the Baja California Peninsula in 2021.
Baja California Peninsula
Baja California Sur
Total Species Recorded
Total Species Confirmed Nesting1
Rare and Uncommon Species2 Unrecorded
Ross’s Goose, Mexican Whip-poor-will, Black Rail, Mountain Plover, South Polar Skua, Black-legged Kittiwake, Sooty Tern, Arctic Tern, Wedge-tailed Shearwater, Townsend’s Shearwater, American Bittern, Northern Saw-whet Owl, Dusky Flycatcher
1 these numbers are difficult to obtain because few observers focus on documenting—or recording—nesting; we include them here as encouragement for observers to pay more attention to nesting evidence for future reports
2 as defined by Erickson, R. A., G. Marrón, E. D. Zamora-Hernández, and M. J. Billings. 2020. Notable bird observations for Baja California and Baja California Sur, August 2016 through December 2019, with an updated checklist for the states. <https://wp.me/p8iY2g-91t> North American Birds.
Abbreviations: BC (Baja California); BCS (Baja California Sur); Mcp (municipio); I. (Isla); Is. (Islas); ph. (photograph); aud. (audio recording); † (description).
Waterfowl through Waders
Goose numbers were generally unremarkable, however 40 Cackling Geese at Estero La Misión 19 Oct (ph. Erin Dunigan) more than doubled the previous regional high count. This is testament to the remarkable population recovery of the Aleutian Cackling Goose. Unseasonal summer geese included long-staying birds at urban parks in Mexicali (Canada Goose since 2010) and Tijuana (Greater White-fronted Goose since 2005); a Snow Goose on Bahía San Quintín 20 Jun (Mark J. Billings, ph. Elia Benítez), establishing the first summer record of the species in BC; and an extremely worn Brant at the Mexicali country club 9 Nov (presumably summered; ph. Logan Q. Kahle). Ducks in similar roles in BCS in Jun included Blue-winged Teal, Northern Shoveler, American Wigeon (6), and Lesser Scaup. Most remarkable of these was Northern Pintail at Guerrero Negro, where an amazing high of 134 was present 18 Jun (ph. Sara Alcalá Jiménez). Other notable ducks were a Wood Duck on the Maneadero Plain 31 Oct (Logan Q. Kahle), up to four Eurasian Wigeons in BC and one at Guerrero Negro 13 Dec (†Logan Q. Kahle, Desmond E. Sieburth), a southerly Mallard 16 Dec (Logan Q. Kahle, Desmond E. Sieburth) and Canvasback 24 Oct (†Owen Hilchey, Phil Chaon) at Guerrero Negro, two more Canvasbacks at Estero San José 2–29 Jan (ph. Ian Davies et al.), White-winged Scoters at Estero Punta Banda 19 Jan (ph. Jonathan Vargas et al.) and La Joya 10 Dec (†Logan Q. Kahle, Desmond E. Sieburth), and Black Scoter offshore from Lagunita El Ciprés 16 Jan (ph. Jonathan Vargas et al.). To draw attention to the new map from CONABIO (Comisión Nacional para el Conocimiento y Uso de la Biodiversidad) assigning the Gulf of California’s I. San Pedro Mártir to BC (rather than Sonora), we note first (?) records there of Ruddy Duck and Turkey Vulture 18 Oct (Lauren Dolinski).
Regional Inca Dove records away from the Colorado Desert are problematic, and should be well documented. We have discounted a number of previous extralimital records when it was clear that observers were unaware of the significance of their claims and provided inadequate documentation. There is no justification for the generous mapping in the Birds of the World species account or the accompanying claim that “Apparently Incas were previously in all or most of Baja California.” Impressive (and well documented!) records this year were of five at Tecate 7–14 Nov (ph. Jack Crawford) and one on the Maneadero Plain 15 Oct (ph. Jonathan Vargas).
Groove-billed Ani persisted at Estero San José with a maximum of four seen 12 Aug (ph. Don Green). Three at La Paz 22 Jun (Gerardo Marrón) were where the species has been reported much less often. Approximately 80 km north of La Paz, a Yellow-billed Cuckoo on Arroyo el Potrero 16 Jul (ph. Enrique Flores García) established the northernmost record for the Cape District/BCS. A Chimney Swift documented at El Rosario 22 Oct (ph. †Logan Q. Kahle) was a more challenging identification and established the first BC record; another possible Chimney Swift near Bocana de Santo Tomás 8 Nov (ph. Steve N. G. Howell, ph. R. A. Erickson) could not be confirmed. Vaux’s Swift is rare in BCS, where two were at San Juan de la Costa 13 Jan (Gary J. Strachan) and one was at San Ignacio 23 Apr (Richard E. Webster, Rose Ann Rowlett). Allen’s Hummingbird was confirmed in BCS for the first time, with two at Loreto 27 Nov–10 Mar 2022 (ph. Tom Haglund; identification confirmed by Sheri L. Williamson). Previous sight reports (Great Basin Naturalist 57: 131–141; Monographs in Field Ornithology 3: 128; North American Birds 66: 592) have been discussed previously and considered hypothetical (Monographs in Field Ornithology 3: 192; North American Birds 66: 592). The only Broad-billed Hummingbird found was at El Rosario 7 Nov (ph. †Logan Q. Kahle), where it established the fifth BC record. An unidentified hummingbird in the Gulf of California many miles from shore north of Santa Rosalía 21 Dec (Steve Stevens) was unseasonal, whatever species it was.
For the 11th consecutive year, what was presumably the same mixed pair of Black and American Oystercatchers nested near La Ventana in Feb (Gary J. Strachan). As usual, few golden-plovers were found: American Golden-Plover at Estero San José 12 Apr (ph. Luis Óscar Carretero Bonilla, Alberto García) and 3 Pacific Golden-Plovers (BC Feb, Mar; BCS Nov). In regional terms, the rarest shorebirds of the year were Hudsonian Godwit at Guerrero Negro 13–15 Sep (ph. Kurt A. Radamaker, Sara Alcalá Jiménez) and Ruff at Lagunas de Chametla 18 Sep (Víctor O. Ayala-Pérez, ph. Jorge Cristerna). Other rare/uncommon fall shorebirds found in typical numbers included Stilt Sandpiper (4), Pectoral Sandpiper (18), and Semipalmated Sandpiper (2). Exceeding expectations were 48 Baird’s Sandpipers and 19 Solitary Sandpipers. Also unexpected were a Red Knot at Playas de Rosarito 7 Nov (first for the municipio; ph. Efraín Octavio Aguilar Pérez), a Red Phalarope inland at Rancho Meling 25 Jan (ph. Anny Peralta-García), and a Lesser Yellowlegs in the Sierra Juárez at Laguna Hanson on the unseasonal date of 18 Jan (Nathan Pieplow, Andrew Spencer).
Surprisingly, the year’s two Common Murres (both 20 Oct on the far northern coast of BC) exceeded the single Rhinoceros Auklet seen, off Ensenada 11 Dec (Logan Q. Kahle)—although note that the auklet was unrecorded altogether in 2020. While this may be due primarily to coincidence, the outnumbering of Iceland (Thayer’s) Gulls (five in northern BC) by Lesser Black-backed Gulls (four in northeastern BC and three in northwestern BC), on the other hand, demonstrated the reality that the former (formerly uncommon) species is contracting northward on the winter grounds while the latter (formerly strictly Old World) species continues its conquest of the New World. Three Sabine’s Gulls inland at Presa Rodríguez, Tijuana, 10 Sep (one; R. A. Erickson, Logan Q. Kahle) and 11 Oct (two; Peter A. Gaede, Robert A. Hamilton, Steve N. G. Howell) were noteworthy, as was a Laughing Gull at Estero Punta Banda 27 Dec (Mark J. Billings, Elia Benítez) and Franklin’s Gulls on the Río Colorado 31 Mar (ph. Jonathan Vargas et al.), at Rosarito 20 Oct (ph. Logan Q. Kahle), and Puerto San Carlos 30 Nov (ph. Xavier Rufray). Notable Least Tern observations were of an early bird at Loreto 8 March (†Emily Feicht) and an inland bird along the Río Colorado 25 Aug (Benito Rocha Brambila). Late or wintering terns at La Paz 5 Dec included 5 Gull-billed Terns, one Common Tern, and 8 Elegant Terns (Clive Harris). Loons summering at Playa La Misión included 3 Pacific Loons, 3 Common Loons, and one unexpected Red-throated Loon seen 17–19 Jul (R. A. Erickson).
Northern Fulmars were well reported in Dec, all the way to Cabo San Lucas. The most notable of all was an individual in the Gulf of California off Loreto 10 Dec (ph. fide E. D. Zamora-Hernández). Rarely reported shearwaters included individuals of Flesh-footed Shearwater 13 Nov (Paul E. Lehman, ph. Barbara Wise et al.), Buller’s Shearwater 17 Sep (Jimmy M. McMorran), and Short-tailed Shearwater 17 Nov (ph. René Valdés, ph. Jonathan Vargas, Ricardo Guerra), all in what we now consider the Pacific waters of Tijuana Mcp. Masked, Nazca, and Red-footed Boobies were also reported north to Tijuana waters in the fall (Brown Booby nested on Is. Coronado as usual), but Blue-footed Booby was not seen in the Pacific north of Is. San Benito (two 9 Dec, Steve Stevens). A Nazca Booby found dead at Estero Punta Banda 16 Jun (Jonathan Vargas et al.) established the first specimen record for the region, while a record high-count of 30 accompanied a cruise ship northwest of Cabo San Lázaro 2 Dec (Robert Horton, ph. Jacob Langford).
The adult Wood Stork seen at La Paz 10–16 Apr and 22–30 Nov is believed to be the same individual that has wandered between La Paz and San José del Cabo since Sep 2017. Rare in the northeast were a Tricolored Heron 8–13 Apr (†José Juan Butrón Rodríguez, †Juan Ángel Butrón) and a Yellow-crowned Night-Heron 14 May (†Richard E. Webster), both on the Río Colorado. Also unexpected were a Yellow-crowned Night-Heron at Is. Coronado 20 Oct (the islands’ first; ph. Logan Q. Kahle) and a White Ibis at Estero Guerrero Negro, BC, 25 Dec (†Michele Ostrander). But long anticipated was the first documented nesting of White-faced Ibis in BCS, with three nests at La Paz 22 Jun (ph. G. Marrón, Luisa Marrón; Western Birds in press).
Raptors through Pipits
The White-tailed Kite is an enigma in our region; it is irregular and generally rare. A count of 61 kites north of Licenciado Gustavo Díaz Ordaz, BC 10 October—foraging in a productive agricultural area and presumably staging in the vicinity of a communal roost site—was more than double the previous high count. Indeed, we are aware of few previous double-digit counts. At least 23 kites remained in the area on 7 Nov (all Steve N. G. Howell et al.). Ten Broad-winged Hawks were in BCS and the only one in BC was on the Río Colorado 20 Apr (†Logan Q. Kahle), where it established the first regional spring record. The status of Zone-tailed Hawk has changed in recent years. The species was formerly very local in the nesting season but now is being reported widely throughout the year. Examples this year included one at Mexicali 23 May (Xóchitl Zambrano et al.) and one at Ensenada 18 Jul (Jonathan Vargas et al.). Elf Owl is presumably resident in extreme southeastern BC, but one at Misión Santa Gertrudis 15 Dec (ph. Logan Q. Kahle, Desmond E. Sieburth) established the first acceptable state record since one was collected by L. M. Huey farther west-northwest near Calmalí in 1947.
An unseasonal Belted Kingfisher at Estero Punta Banda 21 Jun (Mark J. Billings, E. D. Zamora-Hernández) established the first regional summer record. Two Yellow-bellied Sapsuckers were seen in BC in Oct, and the southernmost Red-breasted Sapsucker was at Bahía de los Ángeles 9–23 Nov (ph. George Flicker, Mary Flicker). Lewis’s Woodpecker made a strong showing, beginning with the Colorado Desert’s first at Mexicali 21 Oct (†René Valdés, Jonathan Vargas). Two more were seen at Valle de Guadalupe, and five remained northeast of Ensenada at Valle de Tempe through the end of the year (ph. Jonathan Vargas et al.). Ladder-backed Woodpeckers at Ensenada in Jan and Nov (ph. Isabel Raymundo et al.) suggest that the species may be expanding its range slowly northward along the coast. A Hairy Woodpecker near Rancho Japá 29 Oct (René Valdés, Jonathan Vargas, Ricardo Guerra)—like birds at Tecate in Nov 2011 and Apr 2013—was approximately midway between established populations in the Sierra Juárez and south-central San Diego County. This species is able to disperse considerable distances, but anticipated warming and drying of the area may ultimately sever the genetic continuity of less vagile species along the spine of the peninsular ranges.
An Olive-sided Flycatcher at Guerrero Negro on 1 May (ph. Sara Alcalá Jiménez) was the sixth to be found in BCS. The birds are all from the Guerrero Negro/Vizcaíno Peninsula area and are evenly split between spring (May) and fall (Sep/Oct). Also on 1 May, a migratory push brought a Western Wood-Pewee, Cassin’s Vireo, three Warbling Vireos, Townsend’s Warbler, three Hermit Warblers, two Western Tanagers, Black-headed Grosbeak, and a Lazuli Bunting to I. Guadalupe (Álvaro San José), where several of these species had not been recorded previously. Best of the spring migrant Empidonax flycatchers was a Hammond’s Flycatcher in BCS at Guerrero Negro 8 May (ph. Sara Alcalá Jiménez). In fall, three Least Flycatchers and two Hammond’s Flycatchers were all in BC in Oct (as usual, Dusky Flycatcher was unrecorded). Apparently wintering birds north of the Cape District included a Least Flycatcher at Bahía Asunción 15 Oct (same location as in 2020, but not seen thereafter; ph. Logan Q. Kahle), Hammond’s Flycatcher at El Rosario 12 Dec (†Logan Q. Kahle, Desmond E. Sieburth), and a Pacific-slope Flycatcher at Ensenada 19 Jan–20 Mar (ph. Roberto Pineda et al.). Best of the other noteworthy flycatchers for the year were Eastern Phoebes at Estero La Misión 2 Nov–8 Dec (ph. Logan Q. Kahle et al.) and Tijuana 26 Nov–5 Mar 2022 (ph. Jonathan Vargas, ph. Johan Bergkvist); Dusky-capped Flycatcher at Guerrero Negro 23–24 Oct (first for the Vizcaíno Desert; ph. †Logan Q. Kahle et al.); continuing Great Kiskadee at Estero San José seen on scattered dates throughout the year (Stephen Cherrier, ph. Kevin Bauman, ph. Mick Griffin et al.); Thick-billed Kingbird in Ensenada 23 Oct (26 years to the day after the only previous BC record; ph. †Yuriko Kuwabara); and Scissor-tailed Flycatchers at Maneadero Plain 10–18 Dec (†Logan Q. Kahle, ph. Rafael Paredes Montesinos et al.) and La Paz 16 Dec (ph. Joaquín Corrales, Jorge Cristerna).
A Bell’s Vireo singing near Ensenada 27 Feb (E. D. Zamora-Hernández, Isabel Raymundo) was record early, and in a pattern typical of recent years, three Yellow-green Vireos were found (Sep–Oct, BC) but no Red-eyed Vireos. The only Clark’s Nutcracker seen was in the Sierra San Pedro Mártir 4 Apr (ph. José Hiram Licona Hernández); this after two years of above average numbers in the mountains. “Spring” migrant Violet-green Swallows were seen on the far northwest coast by 24 Jan (5 at Bajamar, ph. Kurt A. Radamaker) but, surprisingly, the species remains undocumented in BC in winter. Wintering swallows were generally found in low numbers in the Cape District at the beginning and end of the year, with five Bank Swallows 8 Jan (†Ian Davies et al.) and a Cliff Swallow 31 Jan (†Jorge Cristerna), all at La Paz, being the least expected.
The rarity highlight of the year was the Arctic Warbler on the Vizcaíno Peninsula 24–27 Oct (ph. aud. †Logan Q. Kahle). The only similar Mexican record is sight-only of an Arctic/Kamchatka Leaf Warbler (Phylloscopus borealis/examinandus) from the same peninsula on 12 Oct 1991. Up to two Red-breasted Nuthatches on I. Guadalupe 10 Jan–10 May (†Álvaro San José) were where the species was once resident. Five Gray Catbirds (all in the Vizcaíno Desert Oct–Nov) established a record seasonal showing. Most notable of the three fall Varied Thrushes was one on the Río Colorado 30 Nov (†Alejandra Calvo-Fonseca), establishing the first record for the Colorado Desert portion of the region. Another great Asian vagrant was the White Wagtail at Guerrero Negro 14 Oct (ph. Sara Alcalá Jiménez), the sixth to be found in BCS; photos do not allow identification to subspecies. Red-throated Pipit is a routine Asian vagrant; five were found, all in BC in Oct.
[Correction added 13 July 2022: Nick Lethaby wrote concerning the subspecific identity of this bird. He says that, “The extensively dark greater coverts shown in the photo match Motacilla alba ocularis rather than M. a. lugens, both of which have been documented in California. M. a. lugens typically shows a broad white edge to the lowermost tertial that appears as a white wedge running parallel to the edge of the folded wing. M. a. ocularis (at least first-year birds) lack this obvious white edge. The BCS bird is extensively black in the closed flight feathers and tertials, indicating ocularis.”]
Finches through Dickcissel
A single Purple Finch was found in 2021: Sierra Juárez 17 Jan (†Jonathan Vargas). The only Red Crossbills were eight in the same area in Jan (Type 2; aud. Nathan Pieplow et al.). Like Clark’s Nutcracker, the number of crossbills was markedly down from the previous two years. Pine Siskin and Lawrence’s Goldfinch ventured as far south as southern BC in the fall. Lapland Longspur (one 28 Oct–3 Nov) and Chestnut-collared Longspur (one 28 Oct) were found only at Villa Jesús María (ph. Logan Q. Kahle et al).
Up to 3 Grasshopper Sparrows were together on the Maneadero Plain 4 Oct –18 Dec (Mark J. Billings et al.), but the species was unrecorded in BCS. We wish to emphasize the seasonal occurrence of certain sparrows in the region. As in most years, Chipping Sparrow, Clay-colored Sparrow, Black-chinned Sparrow, Brewer’s Sparrow, and Lincoln’s Sparrow were last seen in BCS in mid to late Apr and returned again in mid-Oct (except for the more local Black-chinned Sparrow that was unrecorded this fall). Lark Sparrow, White-crowned Sparrow, and Green-tailed Towhee spend more time in the state with late and early dates in early May and early to mid Sep, respectively. Any reports of these species in BCS outside these date-spans require careful documentation. Negative observations peculiar to this year were: no Chipping Sparrow reports from May through Aug, even in BC; only one Lark Bunting seen north of the Cape District and only six anywhere Sep–Dec; and no Mountain White-crowned Sparrows north of central BC. More than the usual number of Dark-eyed Juncos descended upon the region in the fall. These were mostly “Oregon” Juncos, of course, with the southernmost bird reaching the Vizcaíno Peninsula. Also reported (often with some degree of impurity noted) were three “Slate-colored” Juncos (probably J. h. cismontanus) and a “Pink-sided” Junco in northern BC, and four “Gray-headed” Juncos, the southernmost on the Vizcaíno Peninsula. Six White-throated Sparrows in northwestern BC were where the species is rare but regularly reported, while one White-throated Sparrow far to the south in the Sierra de La Laguna 23 Dec (†Theadora Block, Zack Mikalonis) established the first record for BCS. A Nelson’s Sparrow at Estero Guerrero Negro 8 Mar (†Andrew Spencer) was the second found in the region in six months, but only the forth overall and the first in BC since Oct 2008. Only two Swamp Sparrows were found, both at Cataviña 3–6 Nov (Steve N. G. Howell, †Logan Q. Kahle, R. A. Erickson). California Towhee was almost unreported from much of the middle third of the peninsula. It appears it may be declining in that area and increased attention to this species is encouraged. In the same area, a Spotted Towhee at Laguna Ojo de Liebre 18 Oct (†Nathan Senner) was the first to be found between I. Cedros and La Paz.
The year in vagrant Icterids was fairly typical, with six Bobolinks in Oct (all BC); two wintering Orchard Orioles at Estero San José in Jan and Nov–Dec; one BCS Bullock’s Oriole (Oct); and three Baltimore Orioles (Oct–Dec, BC). The highlight was a Streak-backed Oriole in Ensenada 6–22 Feb (ph. Enrique Rebelin) that was initially believed to represent the first record for BC, but with the annexation of I. San Pedro Mártir and its one record, it was relegated to second place. Tricolored Blackbird was confirmed nesting only at Rancho Ciénega Redonda, near the California border (250 adults in Apr, first fledglings in May; ph. R. A. Erickson et al.). The maximum count elsewhere was 80 in the Ojos Negros Valley 27 Nov (Jonathan Vargas, ph. Johan Bergkvist) and the only report south of 31°40’N was of four at Mesa San Jacinto 10 Oct (Peter A. Gaede, Robert A. Hamilton, Steve N. G. Howell). A recent summary of the species’ prospects in Mexico is dire.
On a more cheerful note—for rare-bird hunters in our region anyway—the 35 species of wood-warblers recorded (30 in each state) matched the best previous year on record, 2001. This metric results primarily from the complex interaction of productivity on the breeding grounds (largely in Canada), weather patterns across the continent during the fall migratory period, and observer coverage on the ground in our region. Concerning the first two points we note that the fall showing was also exceptional in southern California, and on the final point, we are happy to note the significant contributions from local observers in the Ensenada, Guerrero Negro, and La Paz/Los Cabos areas. This was not the case 20 years ago. A sampling of the fall’s highlights includes an Ovenbird at an unexpected mountain location (Sierra San Pedro Mártir 30 Sep, ph. José Hiram Licona Hernández); Mourning Warblers at Ensenada 24–26 Oct (second BC record; ph. Elia Benítez et al.) and Bahía Tortugas 16 Oct (ph. Logan Q. Kahle, ph. R. A. Erickson, René Valdés); Kentucky Warblers at Playa San Miguel 23 Oct (†Alfredo García, ph. Jonathan Vargas) and Guerrero Negro 6 Oct (second BCS record; Steve N. G. Howell); Cape May Warbler at Cataviña 3 Nov (ph. †Logan Q. Kahle); ten Northern Parulas, with individuals at the Río Colorado and Bahía Asunción remaining into Dec and presumably wintering (Logan Q. Kahle, Desmond E. Sieburth); Bay-breasted Warblers at Rancho Santa Inés 6 Nov and Bahía Asunción 24–26 Oct (both ph. Logan Q. Kahle et al.); five Yellow (Mangrove) Warblers out of habitat northwest to the Vizcaíno Peninsula/Guerrero Negro area; Pine Warbler on the Maneadero Plain 21 Oct (ph. Logan Q. Kahle); and Grace’s Warbler at El Rosario 19 Oct (ph. Logan Q. Kahle, René Valdés, ph. R. A. Erickson). Only two Blackpoll Warblers were seen, continuing the recent trend. Compare this to a high of 22 in the fall of 2011. The most notable winter warbler records were of MacGillivray’s Warbler in BC at Ensenada 16 Jan (Jonathan Vargas, ph. Daniel Garza Tobón et al.); Hooded Warbler at San Dionisio 18 Dec 2020–17 Mar 2021 (ph. Osiel Alejandro Flores Rosas); Blackburnian Warbler in the Sierra de La Laguna 4 Dec (†Clive Harris); Chestnut-sided Warbler at San Dionisio 8 Jan (ph. Osiel Alejandro Flores Rosas); Prairie Warbler at Guerrero Negro 4 Oct 2021–25 Feb 2022 (ph. Sara Alcalá Jiménez et al); returning Townsend’s x Black-throated Green Warbler at El Rosario 10 Oct–12 Dec (ph. Steve N. G. Howell et al.); and Painted Redstart at El Centenario 15–17 Mar (ph. Víctor Anguiano et al.). Our final warbler note concerns a Palm Warbler that landed on a boat in southern California waters 7 Oct, rode along overnight, and departed upon entering Ensenada harbor 8 Oct (ph. Robert B. McNab).
An Hepatic Tanager at El Rosario 12 Dec (ph. Logan Q. Kahle, Desmond E. Sieburth) was the first for BC since Mar 2015. Eight Scarlet Tanagers were evenly divided between BC and northwestern BCS, all within the second half of Oct. Exceptionally late or potentially wintering in BC were a Blue Grosbeak in Ensenada 5 Dec (Celic Montoya, †Elia Benítez, ph. Laura Ibarra) and Black-headed Grosbeak on the Maneadero Plain 18 Dec (R. A. Erickson). Indigo Buntings spanned the seasons with two in spring, two in fall, and one in winter (east of Todos Santos 25 Jan; †Susan Mittelstadt). Dickcissels, on the other hand, were restricted to Oct (one per state).
Two Swinhoe’s White-eyes (Zosterops simplex) at Real del Mar, just south of Tijuana, 10 Dec (†Logan Q. Kahle, Desmond E. Sieburth) established the first record for Mexico. From its core in Orange and Los Angeles Counties, the species’ range has expanded rapidly in coastal southern California over the last ten years and was expected to cross the international border. White-eye taxonomy is complicated, however, and we note that the California Bird Records Committee does not yet consider the specific identity of this population confirmed. Nevertheless, plumage and vocalizations do seem to establish the identification as Swinhoe’s (https://www.californiabirds.org/watchlist.html; fide Marshall J. Iliff).
Fall Vagrant Landbird Summary—A Personal Account
For the second consecutive year, Logan Q. Kahle of San Francisco spent much time in the region and made many observations detailed in this report. From 13 Oct through 8 Nov he birded daily in the Vizcaíno Desert (south of El Rosario; ca. 14.5 person days) and northwestern (ca. 12.5) portions of the peninsula, during the latter portion of the traditional season for vagrant landbirds. He birded alone and with others, but wrote the following account summarizing his personal experiences.
I was fortunate to spend many days on the peninsula this fall, primarily on the coastal slope from Rosarito to the Vizcaíno Peninsula. Watching turnover at numerous pueblos and ranchos on a nearly day-to-day basiswas fascinating and allowed for some understanding of when waves of migrants were passing through the area.
Eastern warblers are always of interest to vagrant-hunterson the peninsula. Reflective of our times, andspecifically this year, I saw five Blackburnian Warblers and not a single Blackpoll Warbler. Northern Parulas and Lucy’s Warblers were seen in good numbers, at nine and 16, respectively. All of theLucy’s Warblers were in BCS. In contrast, the species was not present in numbers in southern California. Scarlet Tanager is oftenfound in higher numbers in the region than in Alta California, and this year was no exception. I saw seven, compared to justfour seen in the entire state of California.
Western migrants trickled down the peninsula in about expectednumbers. Yellow Warblers were curiously absent from most true migrant “traps,” with only about 15 at locations where they were definitelymigrants (i.e. areas lacking suitable wintering habitat); but my efforts occurred late in the migratory period for this species. I saw more than 250 over the fall at localities where they were presumedto be mostly or completely winterers. I saw no migrantMacGillivray’s Warbler and just two definite Townsend’s Warbler migrants. Meanwhile, Pacific-slope Flycatcher was well represented, with more than 50seen. No Willows Flycatchers were seen, but this is an early migrant. Curiously, I found but a single Clay-colored Sparrow northof El Rosario. An apparent single Chipping Sparrow staying for a full three weeks at Rancho San José de Castro was an interestingly long stay, raising the question of how long migrants typically linger at thesetraps. An “Oregon” Junco present for 11 days at nearby Rancho Santa Mónica raisedsimilar questions.
The highlight for my fall was a Siberian vagrant (or “sibe,” for those who don’t have muchtime). It was an Arctic Warbler gracing a smallline of planted flowering bushes in the heart of the Vizcaíno Peninsula. Like chasing a unicorn, I’d come to the peninsula for four falls in vague hopes of running into a bird such as this, and my heartstopped when I first laid eyes on it.
My final foray down the peninsula was in early November. Migration in general had slowed visibly and it felt rather winterythroughout much of the area. Nonetheless, little jewels like a Blackburnian Warbler in a small clump of 8 mesquites near Bahía Asunción or a Bay-breasted Warbler hopping around cow patties at a small ranch keptmy spirits high and an impressive number of interesting birds were seen.
I hope I will be able to stay later in the season in the future, explore areas to the south and east wherecoverage has been minimal historically, and that others will be able to share the beautiful spectacle that is the Vizcaíno Desert during fall migration.
Ensenada in the City Nature Challenge: A worldwide nature competition.
The City Nature Challenge is an international competition that several Mexican cities have become involved in. Reto Naturalista Urbano (as it is called in Mexico) is a citizen science event in which cities worldwide compete to see which one makes the most observations, involves the most participants, and records the greatest number of species in four consecutive days of effort.
An organizing committee involving individuals from different institutions and NGOs was formed to enter the City of Ensenada in this international competition in 2019. It was a good year and more than 11,000 observations of 1,356 species (including 117 bird species) were obtained by 252 participants. Ensenada ranked 25th worldwide (among 159 cities in 26 countries) and third nationally in the number of species observed.
This exciting competition helps people get involved in recording local biodiversity. Although the COVID-19 pandemic affected the number of participants, and therefore, the number of observations, 123 bird species were recorded in 2021. The organizing committee hopes that 2022 will be a better year with more people involved and more species recorded. Readers are encouraged to be part of the City Nature Challenge 2022 in their own hometown, or in Ensenada 29 April–2 May. Take lots of pictures so the world can learn about our incredible biodiversity.
In addition to the observers cited above, we wish to thank the following individuals for uncited observations or other assistance provided during the year: Dave Bakewell, Michael D. Carmody, Nadine de Jong, Daniel Galindo Espinoza, Emer García de la Puente, Kimball L. Garrett, Andrea González, Sierra González, Marshall J. Iliff, Steven G. Mlodinow, Yann Muzika, J. Van Remsen, Ernesto Abel Salmerón Pillado, Eric VanderWerf.
Baja California Peninsula Municipios
Eleven municipios (municipalities) are recognized in Baja California and Baja California Sur, six in the north and five in the south (Figure 1; Kurt Radamaker’s online GIS version of the same is regularly updated and allows users to zoom in on areas of particular interest to them). Others will surely be added in the future; San Felipe has already begun the process of formal recognition. Municipios are comparable to counties in the U.S. and elsewhere, where people go to great lengths to manage their birding activities around county borders. Polygons created on the basis of latitude and longitude (as is typically done for breeding bird atlases) or biological factors would be more useful for scientific analysis, of course, but human nature emphasizes the political over the natural.
Figure 1. The 11 municipios of the Baja California Peninsula—as recognized by the Comisión Nacional para el Conocimiento y Uso de la Biodiversidad (CONABIO) in February 2022—and their offshore waters to 200 nautical miles, unless the nearest point of land lies in another jurisdiction. Map by Kurt A. Radamaker and Salvador Contreras.
With the addition of municipios to the public mapping features on eBird in April 2021, we have the opportunity to track species’ occurrences on the Baja California Peninsula more precisely. Here, for the first time, we present our attempt to list all species recorded in each of the 11 municipios. We list a source of information for every species/municipio nexus. We use eBird as our default source due to the ease of accessing information online. Data from other online sites are also given priority over printed sources for the same reason. In a few cases, our report is the first for certain species in certain municipios. The sources cited almost never give a full account of a given species’ status in a given municipio. We will continue to work with this matrix and future versions will include entries for subspecific groups and season and abundance codes for each species/group in each municipio. Note that we have included records dating into early 2022 in this table, some of which are highly significant and will be treated in more detail in our next annual report.
Like eBird, we follow the “200 nautical miles or nearest point of land” rule for assigning offshore waters to a particular municipio (Figure 1). Eventually we expect our matrix and eBird data to match closely, i.e., the eBird summary page for each municipio will list the same species that we do. For now, however, a few discrepancies remain. Many important records from the literature, private field notes, and our own database that are used here have not been entered into eBird. Also, we have followed the Mexican government agency CONABIO (Comisión Nacional para el Conocimiento y Uso de la Biodiversidad) in recognizing municipio boundaries and these do not (yet?) match eBird’s. The two primary differences are: 1) eBird does not recognize the newly established San Quintín municipio in southern Baja California (that area is still included in Ensenada municipio; also, many gulf islands formerly aligned with the Mexicali municipio are now assigned to San Quintín, as well as I. San Pedro Mártir, formerly affiliated with Sonora!); 2) Rocas Alijos is misattributed to Mulegé municipio rather than Comondú, with ripple effects extending well out to sea.
We anticipate growing interest in municipio-birding and look forward to updating this table regularly.
Birding is a force for good in our society. Learning and sharing about birds translates into concern for birds and the environment, and the American Birding Association provides resources and community for all people interested in birds!