First Record of the Sora in the State of Hawaii
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FIRST RECORD OF THE SORA IN THE STATE OF HAWAII KIMBERLY J. UYEHARA, 73-1270 Awakea Street, Kailua-Kona, Hawaii 96740 The Sora (Porzanacarolina) is the mostcommon and widelydistributed member of the rail family in North America. It breedsas far north as Alaskaand Canada's NorthwestTerritories and winters as far south as Guyana and central Peru (AOU 1998, Melvinand Gibbs1996). Long-distancevagrancy and dispersal to remotelands iswidespread in rails(Taylor 1998). Thispaper reports the firstSora confirmedin the HawaiianIslands and brieflyreviews other recordsof railsin the islands.While the occurrenceof Porzana railsin Hawaii couldbe expected,on the basisof the fossil record,surprisingly, this report is the firstdocumentation of a vagrantof thisgenus in the Hawaiian chain. On 4 September2000, at 07:00, I founda singleSora at KeaholePoint, 10.8 km northwestof Kailua-Konaon the islandof Hawaii. The site was a 0.69-ha settling basin excavated from a recent lava flow. I observed the bird for 20 minutes at close rangewith a 56x NikonED fieldscope.The angleof the morningsun produced ideal lightingconditions. The bird was similarin size to an adjacentRuddy Turnstone (Arenariainterpres). It foragedat the edgeof a patchof makaisedge (Bolboschoenus maritimus)on the easternexposure of a mudflat,cautiously weaving in and out of view, and retreatedback into the sedgesas the morningsun exposedthe fiats.At 06:50 on 15 SeptemberReginald E. and SusanDavid and I resightedthe Sora about 15 m southof its originallocation. Reginald E. Davidvideotaped the birdas it actively foraged,preened, twitched, and crept out overaquatic plants, strategically placing its feetand long toes to keepafloat, typical Sora behavior. It fed on wholewhite egg sacs (later identifiedas those of Trichocorixa reticulata, water boatman) attachedto the undersidesof submergedmakai sedgeleaves and rootstocks,also on smallspiders, moths,and likelymidges and aquaticbeetles. At 07:15 on 22 SeptemberAnthony J. McCaffertyand I observedthe Sora again in the samearea. The bird was last seen activelyforaging on a mudfiatat the edgeof a patchof swollenfingergrass (Chloris barbata).We notedno bandsor injuriesand heardno vocalizations. The plumagecharacteristics of thisbird indicatean adultSora in definitivebasic plumagewith freshlymolted wing feathersand someunusual markings (Figure 1). Peter Pyle of Point ReyesBird Observatoryin Californiamade the species,age, and plumagedeterminations from the videotapein the Hawaii Rare Bird Photo file at Bernice Pauahi Bishop Museum, Honolulu(HRBP VT02). The Eurasianrails were ruledout mainlybecause of the largersize and amountof blackon the face of the Kona bird. Both the LittleCrake (P.parva) and Baillon'sCrake (P.pusilla) lack black on the faceand haveblack and whitebarred undertail coverts. The SpottedCrake (P. porzana)differs from Sora in its overallspotted appearance and red at the baseof the bill (Taylor 1998). The eye color and lack of juvenalplumage on the Kona bird identifiedit as an adult.The iris is red in the adultSora, whereasit is brown in a first- fall bird. Of about 100 Sora specimensat the California Academy of Sciences,San Francisco,Pyle found that all first-fallbirds in earlySeptember had retainedsome of the juvenalbuff or brownin the eyeline,auriculars, and breast,whereas some adults at this time had moltedinto winter plumage,resembling the Kona bird but typically havingmore black on the throat. The throat plumagewas odd for an adult,possibly becausethe birdencountered a lightregime different from that in itsusual range. Light changesin regionswhere local cues to hormonaland molt cycles diverge from normal cuesmay lead to atypicalplumages. The early acquisitionof basicplumage and the oddthroat pattern suggest that thisbird may have been in Hawaiifor morethan a year (P. Pyle pers. comm.). WesternBirds 35:47-49, 2004 47 NOTES , : : .;: ;•' - . .. ß.. ....:. ::."-:..:... "-:,•;•'-'.i.. ,{..:... .:..::i.-;•' '. ' ':' :.-,• '•.. ':'' 14-,'6': '" I . ;: • . .•. ß • . .. Figure 1. Sora at Keahole Point near Kailua-Kona. Hawaii, 15 September 2000. Photo by R. E. David Rallidsare well representedon oceanicislands, showing their powersof dispersal (Slikaset al. 2002, Taylor 1998). AccidentalSora recordsoutside the Americasare predominantlythe result of eastward movement across the North Atlantic, to Greenland,the BritishIsles, Spain, France,Sweden. and Morocco(Melvin and Gibbs 1996). Casual recordsof the Sora for the Pacificbasin are from east-centralAlaska, the Queen Charlotte Islands(AOU 1998). and the GalapagosIslands (Castro and Phillips 1996). In the Hawaiian Islands,records of vagrantsof this family are rare and were previouslylimited to one hypotheticalrecord of the Sora, and one specimenand 5 to 12 observationsof the American Coot (Fulica americana). Many of the American Coot records, however, are uncertain becauseof lack of information on variation in the Hawaiian Coot (F. alai) (R. L. Pyle unpubl.data). On 10 February1992 Peter Donaldson(pers. comm.) sighteda probableSora on the Waipio Peninsulaof Oahu. He had the bird in view for about 10 seconds and made a substantial but unsuccessful effort to relocateit. On 20 November2003 Kurt Pohimanand Donaldson(pers. comm.)reported another Sora at the Kii Unit of the JamesCampbell National Wildlife Refugeon Oahu. The fossilrecord for the Hawaiianchain contains at least13 endemicspecies of the familyRailidae. Twelve of theseare of the genusPorzana, and all are believedto have been derivedfrom multiplearrivals from Asia (eastward)of the widespreadEurasian Baillon'sCrake, Ruddy-breastedCrake (P.fusca), and SpotlessCrake (P. tabuensis). All 12 Porzana railsbecame flightless and are now extinct(Olson and James 1991, Slikaset al. 2002). Two of these,the LaysanRail (P.paltoefl) and HawaiianRail (P. sandwichensis),perished in historictimes (AOU 1998). Today,two endemicHawai- ian rallidspersist. Both are recent colonistsof the Hawaiian Islands(Fieischer and Mcintosh2001), the endangeredHawaiian Coot and endangered Hawaiian Moorhen (Gallinula chloropussandvicensis). The HawaiianCoot is the onlyspecies of extant rail whose remains have been recoveredin the Hawaiian Islands(Slikas et ai. 2002). 48 NOTES I thank Peter Pyle, Andrew Engilis,Jr., RobertPyle, StorrsOlson, ReginaldE. David, Peter Oboyski,Peter Donaldson,Kurt Pohlman,Sharon Reilly, and Kevin Moore for informationand valuable comments on the draft, and CyanotechCorpora- tion and DucksUnlimited, Inc., for logisticalsupport. LITERATURE CITED AmericanOrnithologists' Union (AOU). 1998. Check-listof North AmericanBirds, 7th ed. Am. Ornithol.Union, Washington,D.C. Castro, I., and Phillips,A. 1996. A Guide to the Birdsof the GalapagosIslands. PrincetonUniv. Press,Princeton, N.J. Fleischer,R. C., andMcintosh, C. E. 2001. Molecularsystematics and biogeography of the Hawaiian avifauna. Studies Avian Biol. 22. Melvin, S. M., and Gibbs,J.P. 1996. Sora (Porzana carolina), in The Birdsof North America (A. Poole and F. Gill, eds.),no. 250. Acad. Nat. Sci., Philadelphia. Olson,S. L., and James,H. F. 1991. Descriptionsof thirty-twonew speciesof birds from the Hawaiian Islands: Part I. Non-passeriformes.Ornithol. Monogr. 45:1-88. Slikas,B., Olson,S. L., and Fleischer,R. C. 2002. Rapid independentevolution of fiightlessnessin fourspecies of PacificIsland rails (Rallidae): An analysisbased on mitochondrialsequence data. J. Avian Biol. 33:5-14. Taylor,B. 1998. Rails:A Guide to the Rails, Crakes,Gallinules and Coots of the World. Yale Univ. Press,New Haven, CT. Accepted 2 February 2004 49 .