First Record of an Olive-Backed Pipit in California
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NO'I. FIRST RECORD OF AN OLIVE-BACKED PIPIT IN CA-FORNIA PHIL CAPITOLO, WILL RICHARDSON, RYAN BURNET'r, and PETER PYLE, Point ReyesBird Observatory,4990 ShorelineHighway, StinsonBeach, California 94970 (currentaddress of Capitolo: U.S. GeologicalSurvey, BiologicalResources Division,Western Ecological Resource Center, Dixon FieldStation, 6924 Tremont Road, Dixon, California 95620) The firstOlive-backed Pipit (Ant hus hodgsoni)recorded in Californiawas banded on 26 September1998 on SoutheastFarallon Island, 42 km westof San Francisco. The birdarrived just prior to the largestwave of migrantson the Farallonesin ten years as hundredsof westernbirds and severaleastern vagrants descended on the island duringthe next fivedays. During this period, no Red-throatedPipits (A. cervinus)and only small numbersof AmericanPipits (A. rubescens)were observed.The Olive- backedPipit was seeneach day through29 September. The bird was first seen at 14:50 on the 26th by Burnett when it flushedfrom underneatha Monterey Cypress(Cupressus macrocarpa) and flew toward the east end of the islandin undulatingflight, twice givinga long, buzzycall ("zzrrring") unfamiliarto Burnett.An hour later,Capitolo flushed the bird from undera patchof bushmallow (Lavatera sp.). It calledonce upon take-off ("szeeeeep")and flew to the marineterrace, a flat area of low groundcover consisting primarily of FarallonWeed (Lasthenia minor maritima) and plantain (Plantago sp.). Capitolo quicklyrefound the birdand identifiedit asa pipitby itswhite and brownish olive plumage, slender bill, and tail-pumpingbehavior but was unable to identifyit to species.Only Pylehad prior experienceidentifying Olive-backed Pipits, but he did not arriveon the islanduntil the followingday. At 16:45, Capitoloand Richardsonrefound the birdon the terraceand were joinedby Burnett. With the sunat our backs,we observedthe bird at closerange with binocularsand a spottingscope while it foragedon the terrace.The bird walkedquickly between patchesof plantain,often remainingout of view for severalminutes before briefly reappearingat the edgeof a patch,pumping its tail. It thenslinked away to newcover, holdingits tail nearlyhorizontal and bobbingits headlike a pigeon.During this time, Richardsonnoted the greenishback and blackbrow to the superciliumthrough his spottingscope and tentatively identified it asan Olive-backedPipit. We recordedfield noteswhile following the birdand attemptingto directit backtoward the mistnet. At 18:00, the birdflew backinto the bushmallow and was promptlycaught in the net. Using Svensson(1992) we confirmedthe identificationand telephonedKeith Hansen for assistance.We bandedthe bird, took measurementsand photographs, pulledtwo ventralbody feathers, and releasedit justbefore 19:00. Thoughsecretive, the bird wassighted on the marineterrace each of the next three days,and Pylewas ableto obtainphotographs of the birdin the field.The featherswere depositedat the CaliforniaAcademy of Sciences(CAS) in San Francisco(accession number 87088), and this recordwas acceptedby the CaliforniaBird RecordsCommittee. The bird (Figure1) wasin firstbasic plumage with a partiallypneumatized skull and no indicationof activemolt. The upperpartswere olive green and faintlystreaked, with heavyblack flecking on the crown.The broadsupercilium was white behind the eye,orange-buff in frontof the eye,and was bordered above by a thinblack brow. The auricularswere olive brown with a whitishpatch at the upper rear, just below and behindthe end of the supercilium.A blackishspot was immediately below this patch. A buff-whitesubmoustachial stripe and throatwere set off by a thin but distinctblack 112 Western Birds 31:112-116, 2000 NOTES Figure1. Olive-backedPipit (Antbushodgsoni), Southeast Farallon Island. Califor- nia. 26 September1998. Thoughnot diagnostic,the pale and dark rear auricular spotsand the darkbrow to the superciliumare importantfield marks. The difference betweenprimary 6 andthe tip of thewing (primary 8; seetext) suggests the subspecies yunnanensis.as this differenceis usually<1 mm in A. h. hodgsoni. Photo by Dan Murley malar stripe.The breastwas buff with bold blackstreaks that becamethinner then endedabruptly at the white belly.The flankswere washed buff with streaksprominent but paler and more diffusethan thoseon the breast.The flight featherswere edged greenish,and the wingbarswere buff, the upper more pronounced.The undertail covertswere white. The inner web of the outer rectricesand the tips of the adjacent pair were duskywhite. Left rectrix4 alsohad a smallamount of whiteat its tip. The upper mandiblewas dark. the lowerpinkish with a dark tip. The legswere pink. We recordedthe followingmeasurements: bill length from nostril8.7 mm; exposed culmen11.0 mm: hind claw 8.3 mm: bill depth at posterioredge of nostrils4.1 mm: billdepth at anterioredge of nostrils3.5 mm: billwidth at posterioredge of nostrils 4.5 mm; bill width at anterioredge of nostrils3.1 mm; wing chord82 mm; tail 62 113 NOTES mm; weight(with band) 21.0 g. Primary 10 (numbereddistally) was reduced. Primary 8 was longestand greaterthan primary7 by more than 1 mm. The Olive-backedPipit is readilydistinguished from all otherpipits by the combina- tion of the olive-greenupperparts, a broadsupercilium that is orange-buffin front of the eyeand white behind the eye,and a hindclaw that isshorter than the hindtoe. The rearauricular spots are also important field marks, though the whitespot is sometimes absentand the dark spotcan be indistinct.The Olive-backedPipit is mostsubject to confusionwith the Tree Pipit (A. trivialis),particularly in badlyworn plumage.The Tree Pipit can also show a white spot on the upper rear auriculars,has a similar postureand gait, a similarcall, and is the only other pipit whosehind claw is shorter than the hind toe (Cramp 1988). Though it has only a faint olive tinge to the upperpartsand its supercilium is narrower and uniformly buff, feather wear can cause the upperpartsto appear more olive in tone and the superciliumpaler. Badly worn Olive-backedPipits may show no olive but rather brownerand grayer upperparts,a fadedfacial pattern, and littlecontrast between the rear and front of the supercilium (King 1981). The Farallonbird was in fresh plumagewith distinctfacial markings. Wing formula can also be helpful in distinguishingthese species,as primary 6 is usuallynot more than 3 mm shorterthan the tip of the wing in the Olive-backedand is 2-6.5 mm shorterin the Tree (Svensson1992). This measurementwas near 2 mm on the Farallonbird, as primary7 wasmeasured more than 1 mm shorterthan the tip of the wing and photographsshow primary 6 to be a similardistance shorter than primary7 (Figure1). The Tree Pipit, furthermore,can be difficultto distinguishfrom the MeadowPipit (A. praten$i$),with identificationdetermined by flightcall or hind clawlength. The MeadowPipit, however,breeding in Greenlandand Europe,is less likelyto occuras a vagrantin westernNorth America,while the Tree Pipit breeds farthereast into southerncentral Siberia (King 1981), and an individualhas reached Alaska (Kessel1989). The four other speciesof pipits occurringin westernNorth America are easily distinguishedfrom the Olive-backedPipit. In fall the Red-throatedPipit differsby havingdark brown upperpartswith broad, conspicuousblack and buff streaksand fairlyuniformly buff underparts. Its flight call is similar,but the Olive-backed'sis louder with a distinctivebuzzy or reedy qualitythat the Red-throated'sthin, high-pitched "seeep"lacks (King 1981, Pylepers. obs.). The PechoraPipit (A. gustavi)is a casual migrant to the westernAleutian Islands(AOU 1998) and is thereforea potential vagrantto California.It resemblesthe fall Red-throatedPipit, but, as in the Olive- backedPipit, itsbully breastcontrasts with a whitishthroat and belly.The Sprague's Pipit (A. spragueii)has sandyor bully brown upperparts,a plain bully face, and narrow streakson the breastthat do not extenddown the flanks.The AmericanPipit hasgrayer upperparts, darker and more uniformsupercilium and underparts,darker legs, and a differentcall (King 1981). However,the race japonicus,a probable vagrantfrom Asia, suspectedon the Farallonesfour timesfrom 1990 to 1999, can showbright pink legs(M. Heindelpers. comm.). Two subspeciesof the Olive-backedPipit are recognized.A. h. hoclgsonihas a much more distinctlystreaked back and crown than A. h. yunnanensis.Nominate hodgsonialso has an unstreakedrump, and the streakingon its underpartsextends farther down the belly than in yunnanensis.Primary 6 is usuallyless than 1 mm shorter than the tip of the wing in hoclgsoni,1-3 mm shorter in yunnanensis (Svensson1992). Thisdifference was approximately 2 mm on the Farallonbird (see above).The faintlystreaked back and rump alsosuggest this birdwas yunnanensis (Figure2), thoughthe faintstreaking on the rumpmay be difficultto distinguishfrom the unstreakedrump of hoclgsoni.The differencein back streaking,however, was obviouson specimensof both subspecieswe viewedat CAS. Nominatehoclgsoni breeds in southernAsia, from the Himalayasto centraland easternChina and Japan;yunnanensis breeds in northernEurasia, east to Kamchatka 114 NOTES ß .* Figure2. Olive-backedPipit (Anthushodgsoni), Southeast Farallon Island. Califor- nia, 26 September1998 The faintlystreaked upperparts also suggest yunnanensis. Photo by Dan Murley and southto Mongolia,Manchuria, Ussuriland, and northernJapan. Their wintering ranges overlap in southernJapan, the Philippines,and peninsularIndia. with hodgsonialso winteringin the RyukyuIslands. Taiwan,