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Noteworthy Observations from Northeastern Baja California

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Noteworthy Observations from Northeastern Baja California NOTEWORTHY OBSERVATIONS FROM NORTHEASTERN BAJA CALIFORNIA MICHAEL A. PATTEN, P.O. Box 8561, Riverside,California 92515-8561 KURT RADAMAKER, 945 S. Idaho #132, La Habra, California90631 THOMAS E. WURSTER, 278 Santa Anita Ct., Sierra Madre, California 91024- 2648 Despiteincreased observer awareness of the SaltonSea and the United Statesportion of the lower ColoradoRiver, coverage of adjacentareas in extremenortheastern Baja Californiaremains low and our knowledgeof the avifaunaof that region remainsslight. The MexicaliValley containsa substantialamount of agriculturalhabitat resembling that found just north of the internationalborder in the Imperial Valley. Becauseof the habitat similarity,the statusof manyspecies in northeasternBaja Californiashould be very similarto that known for the Salton Sea or the lower Colorado River.Here we reporton a numberof species,in hopesthat we mayhelp fill somegaps in knowledgeof the Baja Californiaavifauna. SPECIES ACCOUNTS White-facedIbis (Plegadis chihi). Wilbur (1987) listedthis species as "apparentlya rare transient,only a few havingbeen reported in recent years. There are older recordsfrom the Rio Colorado." On various occasionsbetween April 1987 and January 1992, we observedhundreds (e.g., 300-400 on 29 December 1991) feedingin the agriculturalareas near Mexicali.This speciesis commonyear round (althoughnumbers are smallerin spring and summer)in the Imperial Valley and aroundthe southend of the SaltonSea (Garrettand Dunn 1981, Pattenpers. obs.). It is also an uncommontransient and rare winter visitoralong the lower Colorado River(Rosenberg et al. 1991). The White-facedIbis nested irregularly in the Imperial Valleyuntil 1978 (Ryder 1967, Garrett and Dunn 1981) and was recentlyfound nestingthere again at Finney Lake, where "at least 100 pairs" bred in 1991 (Am. Birds45:1160) and 370 pairs bred in 1992 (WilliamR. Radke, fide G. McCaskie). Thus, the White-facedIbis may be increasingin this area, and nestingshould be watchedfor in the MexicaliValley. GreaterWhite-fronted Goose (Anser a lbifrons).Wilbur (1987) calledthis species a "rarewinter visitor," with "smallnumbers likely to showup at any wetlandlocation." Twenty observedby Wursteron 14 January 1990 alongthe Rio Coloradojust south of Algodoneswere likely early springtransients, as the speciesbegins to move throughthe SaltonSea and adjacentareas at thistime. Up to 400 havebeen found alongthe Rio Coloradoin January(Saunders and Saunders1981), furtherindicating a regularmovement through this area. The Saunders'sighting, however, took place in 1964, when the specieswas more common in the West. The recent maximum in the ImperialValley is 41 near Westmorlandon 26 January1992 (Pattenpers. obs.). Hooded Merganser(Lophodytes cucullatus). We observedtwo adult males and threefemales or immaturesfeeding and swimming in the marshadjacent to Campo Mosquedoon 29 December1991; a singlefemale was seen here on 11 January 1992. The white hoods surroundedby a black stripe on the adult males were noticeableat a greatdistance, as werethe warm orange-brownhoods of the others. The three previousrecords for Baja Californiaare of a female collectedby John Xantus at San Jos&del Cabo in February 1860 (U.S. National Museum 31940), one Western Birds 24:89-93, 1993 89 OBSERVATIONS FROM BAJA CALIFORNIA or more seenby Lyman Beldingat La Paz on an unknowndate (Belding1883), and two observedby Rich Stallcupat the mouth of Rio San Telmo on 24 January 1982 (Wilbur1987). HoodedMergansers are scarceanywhere in Mexico(Sada 1989) but are rare and nearlyannual winter visitorsto the SaltonSea and the ImperialValley (Pattenunpubl. data), so futurerecords should be expectedin the MexicaliValley. Black-shoulderedKite (Elanus caeruleus).Wurster observed two near Mexicalion 28 February1987 and singlebirds near Algodoneson 14 January 1989 and 14 January1990. We observedsix individualsbetween Ciudad Morelos and Victoriaon 29 December1991, includingwhat appeared to be two matedpairs (suitable nesting trees existaround many of the rancheriasin the MexicaliValley). There is also a somewhatdoubtful report of two along the Rio Hardy in 1905 (Stoneand Rhoads 1905). This specieswas not listedby Wilbur (1987) as occurringaway from the Pacificcoast in Baja California,although it is rare but regularat the SaltonSea and in the ImperialValley and probablynested at Brawleyin 1975 (Am. Birds 29:1030). The few noted on each of our visitssuggest a smallpopulation near Mexicali. Bald Eagle (Haliaeetus leucocephalus).Wilbur (1987) noted only two recent recordsaway from MagdalenaBay, soan immatureobserved along the Rio Hardyby Wurster on 14 January 1989 is of interest.S. N. Rhoads,an unreliableobserver, reported seeing singlebirds twice along the upper Rio Hardy in February 1905 (Stone and Rhoads 1905). One or two are found at the Salton Sea each winter (Patten unpubl. data), suggestingthe speciesmay occur regularlyin very small numbersin the MexicaliValley. Swainson'sHawk (Buteo swainsoni).Wurster observed two at the LagunaSalada on 4 April 1987. Wilbur(1987) listedonly two recentrecords for Baja California, althoughsmall numbersprobably move throughthe MexicaliValley each spring,as theydo throughthe ImperialValley, where records extend from 4 March(1989, nine near El Centro;Am. Birds43:536) to 11 June (1983, one near PlasterCity; Am. Birds37:1027). The LagunaSalada sighting fits well withinthis time frame. FerruginousHawk (Buteo regalis).Wilbur (1987) consideredthis speciesa winter visitorto the northwesternportion of the peninsula,but neither he nor Grinnell (1928) mentionedany recordsfor northeasternBaja California.On 29 December 1991, we observedfour in agriculturalfields near the townof NuevoLe6n. Sincethis hawk is a rare to uncommonwinter visitorin the vicinityof the SaltonSea (Garrett and Dunn 1981), it almostcertainly winters regularly in the MexicaliValley. Ring-necked Pheasant (Phasianus colchicus). Wurster observed one near Algodoneson 14 January1989, we sawtwo malesand three femalesfeeding in a stubblefield 20 krn southeastof Mexicalion 29 December 1991, and Radamaker observeda male about 15 km southeastof Mexicalion 22 August1992. In addition, Howell and Pyle (1988) reportedobserving five or six pheasantson 4 December 1983 a "few miles south of Mexicali on Route 5." This speciesis rare in the Imperial Valley (Garrett and Dunn 1981), and Wilbur (1987) stated that it had not been recorded acrossthe border in the northeastern portionof Baja California.Wilbur's statement is inaccurate,however, since Leopold (1959) indicatedthat pheasantstock from China was introducedinto the Mexicali Valleybeginning in 1912. By 1922, the Ring-neckedPheasant was established in the Mexicali Valley (Hart et al. 1956). Leopold (1959) estimateda densityof 50 pheasantsper squaremile (about 19/krn 2) between the Imperialand Mexicali valleys, althoughhe indicatedthat there were more birds in the MexicaliValley where the "habitat is better." The MexicaliValley was openedto pheasanthunting in 1929, with a bag limit of two birdsand an estimatedaggregate kill there of 1000 birdsper year by 1948/49 and 1949/50 (Hart et al. 1956). CurrentMexican hunting regulations specify a bag 9O OBSERVATIONS FROM BAJA CALIFORNIA limit of three birdsand a seasonallimit of sixbirds (E. Mellinkpers. comm.),implying that the speciesis quite common in the valley. Lesser Yellowlegs(Tringa flavipes). Wilbur (1987) stated that this species is "apparenfiyan irregularfall transientand winter visitor" with "onlyfive records." On 29 December 1991, we observedat least ten in a floodedfield roughly 25 km southeastof Mexicali.Since the LesserYellowlegs is an uncommontransient and rare winter visitor to the Imperial Valley and Salton Sea (Garrett and Dunn 1981), it almostcertainly occurs in the MexicaliValley on a regularbasis. Whimbrel (Nurneniusphaeopus). We observedone on 29 December 1991 in a floodedfield roughly25 km southeastof Mexicali.The short bill (comparedto a Long-billedCurlew, Nurnenius americanus), the grayertone of the plumage,and the distinctblackish head stripes identified the Whimbrel.The birdwas smaller than a curlew but larger than the nearby Willets (Catoptrophorus sernipalrnatus).This observationis noteworthybecause there are only four winter recordsfor the Salton Sea area: one at the southend of the sea on 29 January1989 (Am. Birds43:366), three at the south end on 18 December 1990 (Am. Birds 45:999), one at the north end of the sea on 12 January1991 (Radamakerpers. obs.),and up to two at the southend from 17 December 1991 to 23 February1992 (Am. Birds46:315). Baird'sSandpiper (Ca lidris bairdii).Wilbur (1987) consideredthis species "appar- enfiy a rare transient,[with] five recordsto date," and it is a rare to uncommon migrantthrough the SaltonSea (Garrettand Dunn 1981, Patten pers. obs.).Wurster observedfour in the Mexicaliarea on 9 September1987. LaughingGull (Larusatticilia). This gull is considereda regularwinter visitor, in smallnumbers, on both coastsof Baja Californiasouth of latitude27 ø N (Wilbur 1987). Two observedby Wursteralong the Rio Hardy on 28 February1991 and an adult observedby Radamakerat Campo Mosquedoon 11 January 1992 are probablythe northernmost(both locations are at roughly32.5 ø N) for the speciesin BajaCalifornia during this season, although there are overten winterrecords for the SaltonSea (Patten unpubl. data). This species was recently discovered breeding in the Coloradodelta (Palaciosand Mellink 1992) and has been found in winter at Puerto Pefiasco, Sonora (Am. Birds 45:1009), so future winter records
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