BIRDS OF HOT SPRINGS MOUNTAIN, SAN DIEGO COUNTY, CALIFORNIA

PHILIP UNITT, 3411 Felton Street, San Diego, California 92104

The mountainsof San Diego County have never been the objectof much ornithologicalstudy. The birdsof other nearbyranges in southernCalifornia have been reported on by Grinnell (1908, San BernardinoMts.), Grinnell and Swarth (1913, San Ja½intoand Santa Rosa mts.), and Pequegnat (1945, SantaAna Mts.). Informationfrom the San Diego Countymountains has been publishedonly in a few brief notes or in comprehensiveregional summaries(Cooper 1874, Emerson1887, Belding 1890, McGregor 1899, Willett 1933, Grinnelland Miller 1944, Samsand Stott 1959). The highest peak in the county, isolatedHot SpringsMountain, has apparentlynot been previouslyvisited by an ornithologist.Nothing relating to the birdsof thisarea has been published,arid no specimenscollected there have been preserved in the San Diego Natural History Museum or ir• the Museum of Vertebrate Zoology, University of California, Berkeley. I made three visits to Hot Springs Mountain during June and July 1980. The observationshere reported are an attempt to fill this gap in our knowledge of California bird distribution. Mixed coniferous-oakwoodland occurs in San Diego County at elevations above about 4000 feet (1200 m) in situationswhich receive an annual rainfall of over 18-20 inches (460-500 mm). The most extensive areas of this habitat correspondwith five mountainsor mountain ranges. Palomar Mountain, in the north-centralpart of the county,rises to 6140 feet (1871 m). Hot Springs Mountain, with its summit at 6533 feet (1991 m) is separatedfrom Palomar by a broad treelessvalley at an elevationof about 2800-3100 feet (850-950 m). This valley extendseast to separateHot SpringsMountain from Volcan Mountain, 5719 feet (1743 m), to the south. Farther south, in the central portion of the county, the Cuyamaca Mountains rise to 6512 feet (1985 m) on Cuyamaca Peak, and the Laguna Mountains, to 6272 feet (1912 m) on Monument Peak. Woodland habitat on Hot Springs Mountain covers approximately 4 square miles (10 km2), mostlyon the northeasternand southeasternslopes. The dominanttrees in thisarea are JeffreyPine (Pinusjeffreyi), CoulterPine (P. ½oulteri),Ponderosa Pine (P. ponderosa), White Fir (Abies concolor), IncenseCedar (Calocedrusdecurrens), Black Oak (Quercuskelloggii), and Canyon Live Oak (Q. ½hrysolepis).The rest of the mountain is vegetated with dense mixed chaparral, or, particularlyon the south slope, patchesof chaparral scatteredamong grassesand other herbaceousplants. The latter situationis apparentlythe resultof fire, clearingof brush,and cattlegrazing. Three small streamswere flowing on the mountainat the time of my visits. The largestof these, an apparentlyunnamed tributaryof Agua Caliente Creek, descendedthe northeastslope, and along it the greatestnumbers of birds were concentrated.Hot SpringsMountain is accessibleby automobile from the villageof San Ysidro on San Ysidro Creek at the southbase of the mountain.

Western Birds 12:125-135, 1981 125 BIRDS OF HOT SPRINGS MOUNTAIN

Bart Cord and I made the first visitto Hot SpringsMountain on 3 June, arrivingabout 1130, and departingabout noon the followingday. David Poveyand ! made the secondvisit, arriving 1945 on 23 June and departing 1400 on 24 June. The third visit was also made with David Povey; we

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126 BIRDS OF HOT SPRINGS MOUNTAIN arrived1930 on 21 July and left 1300 on 22 July. We concentratedour observationsin densewoodland along and near the creekon the northeast slope,but alsolooked in severalother areason the mountain,and spent sometime on each visitin more open woodlandand densechaparral near thesummit. All speciesseen or heardwere counted as accurately as possible.

HOT SPRINGS MOUNTAIN

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Figure2. Detail of Hot SpringsMountain area, San Diego Co., California. 127 BIRDS OF HOT SPRINGS MOUNTAIN

The timing of our visitswas intendedto cover the breedingseason for most residentbirds, and to avoid the problemof distinguishinglocal breeders from early or late migrants.I believe all speciesobserved were potential, if not actual breederson Hot SpringsMountain, except ($elasphorus)sp. (fall migrantsreach San Diego Countyby late June) and Scott'sOriole (probably a post-breedingwanderer from nearby habitat downslope to the eas..t). Definitereproductive activity (usually fledged young accompanyingadults) was seen in Anna's Hummingbird, Calliope Hummingbird, White-headed Woodpecker,Scrub Jay, White-breastedNuthatch, House Wren, Western Bluebird,Western Tanager, Black-headedGrosbeak, Rufous-sided Towhee and Dark-eyed Junco. Our resultsare summarizedin Appendix1. Most of the speciesobserved are widespreadin the other mountainsof San Diego County and do not require further comment. The occurrence of a few, however, merits discussion. Calliope Hummingbird, $tellula calliope. On 4 June one male was seen in a meadow with scatteredbushes along the creek on the northeastslope, elevation 5400 feet (1650 m). It chasedoff anotherhummingbird of equal size,presumably also a Calliope. On 24 June what was very likelythe same male wasseen in the samebush. It was displayingto a female: three or four steepdives in front of the female followed by a very slow descent.The birdsalso hovered in front of each other, very close together,but we did not see actualcopulation. On 22 July a singlefemale was seen near the samearea. Thisis the firstsummer report of CalliopeHummingbird from San Diego County; potentiallybreeding birds had previouslybeen noted southto the San JacintoMountains, where Dawson(1916) saw displayingmales near Idyllwildand in Tahquitz Valley. Dusky Flycatcher,Empidonax oberholseri. One was heard on 3 and 4 June about 1.3 miles (2.1 km) southeastof the summitat 6200 feet (1900 m) elevation.Dusky Flycatcherhas only recentlybeen found as a rare summervisitor south to San Diego County. I have also seen the speciesnear the summitof Cuyamaca Peak (one on 1 July 1979) and alongAgua DulceCreek in the LagunaMountains (pair with youngin neston 14 July 1974; 2 on 24 July 1976). David Poveysaw a pair feedinga fledgling Brown-headedCowbird near CibbetsFlat, Laguna Mountains, on 4 July 1978. BreedingDusky Flycatchers were recordedpreviously south to the San Jacintoand Santa Rosa mountains, where Grinnell and Swarth (1913) found them "in abundance." Red-breastedNuthatch, $itta canaden$i$.One was heard callingon 24 June in a very densestand of treeson a steepnorth-facing slope 1.3 miles(2.1 km) eastof the summitat 5900 feet (1800 m) elevation.Until recently,the breedingrange of thisnut- hatch extended south in California to the San Jacinto Mountains, where Grinnell and Swarth (1913) found it in Tahquitzand Round valleys.The specieshas been noted a few timeson PalomarMountain, including a pair nestingin summer1970 (McCaskie 1970) and a singlebird on 19 May 1975 (Jon Dunn, field notes). In southwesternSan Diego County, Red-breastedNuthatches colonized planted coniferson Point Loma, whereyoung were seenbeing fed in summer1964 (McCaskie1966); the specieshas remained there ever since. Hermit Thrush, Catharu$ guttatu$. One was heard singingon 24 June in the same place where the Red-breastedNuthatch was noted. Although we were never able to see the bird, we approachedit closelyand heard the characteristicsong very well: 128 BIRDS OF HOT SPRINGS MOUNTAIN well-spacedphrases, each phrase composed of a clearwhistle followed by a seriesof risingand fallingrapid notes. Hermit Thrusheshave been recordedin the nesting seasonsouth only to the San BernardinoMountains, so the presentobservation was completelyunexpected. Black-throatedGray Warbler, Dendroica nigrescens.The numbersseen of this specieswere surprisingsince it is very rare during the breedingseason in San Diego County. I had previouslyseen it in the breedingseason only three times,on Palomar Mountainon 26 June 1976, and in the Laguna Mountainson 13 July 1974 and 22 May 1975. Very littleinformation is availableon the breedingstatus of Black-throated Gray Warblerin San Diego County. Grinnelland Miller (1944) reportit from Vallecito and the Cuyamaca Mountains, but it is undoubtedlyonly a migrant at the former locality. The San Diego Natural History Museum has two June specimensfrom Palomar Mountain (SDNHM 1414 and 19188), and the Western Foundation of VertebrateZoology has one egg setfrom Julian and anotherfrom the Laguna Moun- tains (WFVZ 72757 and 82925). Green-tailed Towhee, Pipilo chlorurus.On 4 June one was seen about 1.5 miles (2.4 km) northeastof the summit. On 24 June two were seen together 1.3 miles (2.1 km) eastof the summit.On both occasionsthe birdswere in open woodlandwith scat- tered bushesand low herbaceousgrowth. Until recently, Green-tailedTowhee was known in summersouth only to the San JacintoMountains. In 1978 small numbers were discoverednear the summitof CuyamacaPeak (D. Povey), and a juvenilewas seen accompanyingadults there on 29 July (pers. obs.).

DISCUSSION

The summer distributionof montane birdsamong severalmountain ranges in southernCalifornia and northern Baja Californiais presentedin Table 1. This table is an expansionof Miller's (1951) Table 7, but I have includedonly those specieswhose breedingranges are confinedto elevationsabove 4000 feet in the mountain rangeslisted. Footnotesrefer principallyto localities reported for a speciessince Grinnell and Miller (1944). The mountainsof San Diego County form a rather low area along the mountain systemof the Transverseand Peninsularranges. To the north, Mount San Jacinto reaches an elevation of 10831 feet (3301 m); to the south, the highestsummit in the Sierra San Pedro Martir reaches 10135 feet (3089 m). The low elevation and small extent of coniferous forest habitat in San Diego County have made the area a barrierto the dispersalof boreal forestbirds. Information in Grinnell and Miller (1944) and Miller (1951) indi- cates that 12 speciesreach the edges of their breeding ranges in the San Jacintoor Santa Rosa mountains(the report of Sharp-shinnedHawk nesting in San Diego County is undocumentedand probablyerroneous). An addi- tional 7 species,absent as breedersin San Diego County, reappearto the southin the Sierra Juarezor Sierra San Pedro Martir. In recentyears, 12 of these 19 have been noted during the nestingseason in San Diego County mountains.Four (Red-breastedSapsucker, Dusky Flycatcher, Red-breasted Nuthatchand Green-tailedTowhee) have definitelynested, and two others (CalliopeHummingbird and Fox Sparrow) have probablydone so. All these situationshowever involve very small, localizedor ephemeralpopulations, and do not significantlyalter the basicpattern of bird geography. 129 + + x x x o x x +

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130 BIRDS OF HOT SPRINGS MOUNTAIN

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131 BIRDS OF HOT SPRINGS MOUNTAIN BIRDS OF HOT SPRINGS MOUNTAIN

The mountainsof San Diego County, though not supportinga continuous area of coniferouswoodland habitat, neverthelesscompose a cohesive regionof birddistribution, as originallyindicated by Miller(1951). No major breaksin the distributionof any speciesoccur between any of the five moun- tain areas.Any differencein the avifaunaof the variousranges involves the marginalspecies mentioned above, or is probablyan artifactof inadequate exploration.As wellas lacking several species present in the SanJacinto and Santa Rosa mountains, the avifauna of the San Diego County mountains shows some differences from that of the Sierra Juarez and Sierra San Pedro Martir in Baja California. Saw-whet Owl, White-headedWoodpecker, Steller'sJay and BrownCreeper have not spreadsouth of the international border, while Calliope Hummingbird, Pinon Jay, Clark's Nutcracker, Yellow-rumpedWarbler, Cassin'sFinch, Pine Siskinand Red Crossbill, whichinhabit Baja California,are not regularbreeders in the mountainsof San DiegoCounty. Grinnell (1928) describesother cases of differentiationat the subspecificlevel.

ACKNOWLEDGMENTS

I thank Banning Taylor of the Los CoyotesIndian Reservation,in which Hot SpringsMountain is situated,for grantingpermission to visitthe area. EvelynNorte and Cartie Etheridgekindly providedaccess to the road up the mountain. Guy McCaskieand Jon Dunn generouslysupplied information from their personalfield notes. ElizabethCopper read and commentedon the manuscriptand greatly helped with the figures.I especiallythank Bart Cord and David Poveyfor their interestin thisproject and invaluablesupport in the field.

LITERATURE CITED

Belding, L. 1890. Land birdsof the PacificDistrict. Occas. Pap. CaliforniaAcad. Sci. 2:1-274. Cooper, J.G. 1874. Animal life of the Cuyamaca Mountains. Am. Nat. 8:14-18. Dawson, W.L. 1916. A personalsupplement to the distributionallist of the birds of California. Condor 18:22-30. Devillers,P. 1970. Identificationand distributionin Californiaof the $phyrapicus varius group of sapsuckers.Calif. Birds 1:47-76. Emerson, W.O. 1887. Ornithologicalobservations in San Diego County. Bull. California Acad. Sci. 2:419-431. Forfiner,J.C. 1920. Clark Nutcrackerand White-wingedDove in southernCalifornia. Condor 22:190. Grinnell, J. 1908. The biota of the San Bernardino Mountains. Univ. California Publ. Zool. 5:1-170. Grinnell,J. 1928. A distributionalsummation of the ornithologyof Lower California. Univ. California Publ. Zool. 32'1-300. Grinnell, J. & A.H. Miller. 1944. The distributionof the birds of California. Pac. Coast Avif. 27.

133 BIRDS OF HOT SPRINGS MOUNTAIN

Grinnell, J. & H.S. Swarth 1913. An account of the birds and mammals of the San Jacinto area of southern California. Univ. California Publ. Zool. 10:197-406. McCaskie, Go 1966. The nestingseason. Southern Pacific Coast region. Aud. Field Notes 20:545-547. McCaskie,Go 1970. The nestingseason. Southern Pacific Coast region. Aud. Field Notes 24:715-718. McGregor,R.C. 1899. Some summerbirds of PalamarMountains, from the notes of J. Maurice Hatch. Bull. Cooper Ornithol. Club 1:67-68. Miller, AoHo 1951. An analysisof the distributionof the birdsof California.Univ. California Publ. Zool. 50:531-644. Pequegnat,W.R. 1945. Report upon the biota of the Santa Ana Mountains. J. Entomol. Zool. 37:25-41. Sams, J oR. & K. Stott, Jr. 1959. Birds of San Diego County, California:An anno- tated checklist.Occas. Pap. San Diego Soc. Nat. Hist. 10:1-49. Willett, G. 1933. A revised list of the birds of southwesternCalifornia. Pac. Coast Avif. 21. Winter, J. 1974. The distributionof the Flammulated Owl in California. West. Birds 5:25-44.

Appendix 1. Speciesand numbersof birdsobserved on Hot SpringsMountain, San Diego Co., California.The three numbersindicate respectively the numbersof each speciesrecorded on each of the threetrips. Time spentin observationwas 14 hourson 3-4 June, 9 hours on 23-24 June, and 8 hourson 21-22 July, 1980.

Red-tailedHawk Buteojar•aicensis(4, 1, 1), MountainQuail Oreortyxpictus (16, 4, 4), Band-tailed Pigeon Colur•fia fas½iata(20, 9, 13), Mourning Dove Zenai•ta r•acroura(8, 3, 2), Anna'sHummingbird Ar½l•ilocl•us anna (14, 8, 3), CalliopeHum- mingbird(2, 2, 1), Rufous/Allen'sHummingbird $elaspl•orus sp. (0, 0, 5), Common Flicker Colapresauratus (6, 4, 4), Acorn Woodpecker l•elanerpes forr•icivorus (42, 28, 30), Hairy WoodpeckerPicoi•/es villosus (4, 4, 2), Nuttall'sWoodpecker Pi½oi•tes nuttallii (2, 0, 2), White-headedWoodpecker Pieoldies alfiolar•atus (2, 13, 8), Ash- throated Flycatcherl•yiarcl•us cinerascens(13, 9, 9), Dusky Flycatcher(1, 0, 0), Western Flycatcherœr•pi•tonax •tifficilis (3, 3, 0), Western Wood Pewee Contopus sor•ti•tulus(18, 11, 10), Olive-sidedFlycatcher Contopus florealis (2, 2, 3), Violet- green Swallow Ta½l•y½inetatl•alassina (30, 25, 25), Steller'sJay Cyano½ittastelleri (37, 22, 19), ScrubJay Apl•elo½or•acoerulescens (13, 1, 5), Common Raven Cor- •us corax (2, 1, 0), Mountain Chickadee?arus garbbell (80, 66, 62), Plain Titmouse ?arus inomatus (13, 5, 14), Bushtit Psaltriparusr•inir•us (4, 8, 6), White-breasted Nuthatch $itta carolinensis(10, 9, 10), Red-breastedNuthatch (0, 1, 0), Pygmy Nuthatch$itta pygr•aea (3, 2, 0), Brown CreeperCertl•ia far•iliaris (8, 4, 2), Wrentit Cl•ar•aea fas½iata(7, 5, 8), House Wren Troglo•tytesae•ton (39, 22, 20), Bewick's Wren Tl•ryor•anesfiewickii (1, 0, 5), CaliforniaThrasher Toxostor•a re•ti•i•ur• (2, 2, 0), AmericanRobin Tur•tusr•igratorius (0, O, 2), Hermit Thrush (0, 1, 0), Western Bluebird$ialia r•exicana (43, 15, 21), Orange-crownedWarbler Verr•ivora celata (0, 2, 4), Black-throatedGray Warbler (0, 1, 3), Scott'sOriole lcterusparisorur• (0, 0, 1), NorthernOriole lcterusgalfiula (0, O, 1), Brown-headedCowbird l•olothrus ater (3,

134 BIRDS OF HOT SPRINGS MOUNTAIN

Appendix 1 (Cont.)

3, 3), WesternTanager Piranga ludoviciana (18, 9, 10), Black-headedGrosbeak Pheucticusmelanocephalus (6, 0, 17), PurpleFinch Carpodacus purpureus (13, 4, 4), HouseFinch Carpodacus mexicanus (0, 6, 5), LesserGoldfinch Carduelis psaltria (4, 14, 10), Lawrence'sGoldfinch Carduelis lawrencei (0, 2, 3), Green-tailedTowhee (1, 2, 0), Rufous-sidedTowhee Pipiloerythrophthalrnus (3, 22, 18), Lark Sparrow Chondestesgrammacus (1, 2, 4), Dark-eyedJunco Junco hyemalis (67, 23, 14), Chipping Sparrow Spizellapasserina (1, 1, 0), Black-chinnedSparrow Spizella atrogularis(5, 0, 0). Accepted 4 September 1981

Black-throatedGray Warbler Sketch by Tim Manolis 135