The Vagrancy of Gray Kingbird in North America
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Tfl f Gca ird in N t 1Ti ica GeorgeL.Armistead ABSTRACT andfall appearances to "misorientation," both Thispaper summarizes extralimita] records, phenomenathat are wall documented in simi- 1216Clarion Street includingbreeding records beyond the core larspecies. range,of GrayKingbird (Tyrannus dominicen- In the compilationof recordsaway from Philadelphia,Pennsylvania 19147 sis) in North America, almostall of which are corerange, we find clear patterns of vagrancy fromcoastal areas along the Atlantic and Gulf Bothspring and fall records out of core range (email:[email protected]) Coasts.Most recordsof vagrantsare over- showbimodality. The bimodalityin spring whelminglylikely to be from migratory popu- maybe attributableto differentialmigration lations,but specimens ofvagrants are few and bysex, while the fall bimodality may pertain thetaxonomy atthe subspecific level remains to differentmigrations by ageclasses. Spring MarshallJ. Iliff unsettledenough that positive identification vagrantrecords span the species'normal ofthe source population(s) has not been feasi- migrationwindow. as doesthe earlierfall 246East 16th Street, Unit B ble.Likewise, the dearth of data on migratory peak,but a separate,later fall peak involves pathwaysof GrayKingbird precludes exten- birdsthat appear up toa monthlater than the CostaMesa, California 92627 sive speculationon probablecauses of latest individuals have wtthdrawn from other (email:[email protected]) vagrancy. though here we attributespring portionsof its rangein the UnitedStates. appearancesout of rangeto "overshooting" ]-houghthe displacement of some birds may be affectedby weather,no strongcorrelation betweenpatterns of wind andweather and the vagrancyof thisspecies could be estab- lishedin thissummary. Thereare very few records of vagrants dur- ingsummer (late June through mid-August), and none exist duringwinter awayfrom Floridaand Mississippi. Records of vagrants arechiefly coastal, with just 19from the con- tinent'sinterior. While partially a productof observerbias, the distribution of records illustratesthis species'strong affinity for coastalenvironments. This paper documents an increasein the numberof vagrantGray Kingbirdsrecorded since the 1970s,due in partto a minorrange extension but primarily to the sharpincrease in thepopularity of amateurornilhology in theEast. INTRODUCTION '[he charismaticGray Kingbird(Tyrannus dominiccrisis)is one of eightspecies in its genusthat regularlybreeds in continental NorthAmerica north of Mexico (Figure 1). As humanshave continually reshaped the land- scapethroughout its range. the Gray Kingbird has establisheditself as one of the most ubi- Figure1. AGray Kingbird, probably ajuvenile based onthe brown cast and neat pale margins tothe upperwing coverts,hangs out at Buxton,North Carolina 21 October1993. The Carolinas have hosted almost half of the quitousbirds in its corerange in the West continentsvagrant Gray Kingbirds inthe past 100 years, and the Outer Banks of NorthCarolina have held Indies.An open-countryspecies, it hasbene- mostof those, including atleast one nesting pak. Photograph byStephen J.Dinsmore. fitedfrom the clearing of forestsand the cre- 148 NORTH AMERICAN BIRDS • UNITED STATESi , _ ) ATLANTIC x, / CUBA-....... B•A•AMAS'• - ......... .,.,. blue. hne' . indicates' ' \ ( • • ".-' PUERTO -.._ w•ntenngrange '"x k,. ,J .t JAMAICA•; - ,-.... • -.•½o, '%. "'"'-- -""-'•J---r•V,-..... '•'; HAITI PACI FI C ationof moreopen spaces. In breedingseason, savanna;Monroe and Barron 1980, Lock- essentiallyresident, although some birds are itsboisterous, twittering call is heardcontinu- wood 1999), Sulphur-belliedFlycatcher believed to winter south to northern South ously,variously described as "pit-teer-rrry" or (Myiodynastesluteiventris), Ash-throated Fly- America(Ridgway 1907, A.O.U. 1957,Iray- "pe-cheer-ry"(Peterson 1980), and it enjoys catcher(Mylarthus cinerascens), Variegated 1or 1979, Rodnetet al. 2000). Differencesare an uncommonaffection among humans, evi- Flycatcher(Empidonomus varius; Abbott and slightand poorlycharacterized, but T. d. dencedby thevariety of colloquialnames fas- Finch 1978), and others. We believe that voraxis saidto averagelarger with a larger tened to it, most of which relate to its call: errantGray Kingbirds occur in thespring pri- bill,and darker gray upperparts, with axiltars Petchary,Chinchary, Pitirre, Pitirre AbeFro, marily as "overshooting"northbound andunderwing coverts less strongly yellow- Iitirre, Pestigre,Pipirite, Pick-Peter, Chris- migrants,whereas fall vagrants are presumed ish (Ridgway1907). Geographicvariation tomarie,and Fighter (Bond 1993). to be misorientedbirds engaging in "reverse withinthe species was examined by Brodkorb Gray Kingbirdsbreed from the coastal migration.• In our analysisof records,we (1950) and Habermanet al. (1991), and both southeasternUnited States(Alabama to South havenot been able to establisha strong posi- foundthat sedentary populations were gener- Carolina)south throughout the WestIndies tivecorrelation between particular patterns of allylarger-billed and shorter-tailed. Neverthe- to northern South America (Venezuela;west windor weatherand the out-of-range occur- less,because significant sexual &morphism probablyto Colombiaand perhaps Panama; fencesof Gray Kingbird,although southerly existsin bill lengthand wing shape (Haber- Ridgelyand G•vynne 1989, A.O.U. 1998, Hihy or southwesterlywinds sometimes precede manet al_1991), identification to onegroup 2003). Northern populations--including appearancesof the speciesout of rangein or the otherrequires ascertaining the sex, those in the United States, the Bahamas, bothspring and fall; in oneinstance, a hurri- whichis not possiblein the field.Brodkorb Cuba,the Ca)qnanIslands, and Jamaica-- canehas been credited with thed•splacement (1950) dividedthe speciesinto five sub- wintersouthward from Hispaniola and Puerto of a vagrant, though such is essentiall) species,but thesewere never widely recog- Rico to northern South America (increase in impossibleto demonstrateconclusively. nized,and no differenceswere seen by Mon- numbersdetected fall throughwinter in roe (1968). Habermanet al. (1991) found NethedandAntilles and Irinidad and lobago, TAXONOMYAND THE SUBSPECIFIC significantmorphometric differences among for example;Voous 1983, ffrench 1991). IDENTIFICATIONOF VAGRANTS populationsexamincd by them, with two In thisreview, we consider"vagrant" Gray Determinationof the sourcepopulation of broadgroups discernible: migratory and non- Kingbirdsto be individualsdocumented vagrantswould be of interest,but apparently migratorypopulations. Although a changein awayfrom Florida, Alabama, Mississippi, and individualsare not diagnosible to population taxonomywas suggested by Habermanet al. coastalGeorgia. Gray Kingbirdis proneto or subspeciesin the fieldor perhapseven in (1991)and adopted by Pyle (1997), the study long-distancevagrancy, as are several species hand.Ihe Gray Kingbirdhas traditionall)' wasnot specificall)' designed to addresstaxo- of migratorytyrannids, including Iropical beendivided into two subspecies,nominate nomicissues. For example,they did not Kingbird(Tyrannus melancholicus; Mlodinow T..d. dominicensisover most of therange and examinetype specimens or specimensfrom 1998), Fork-tailed Flycatcher(Tyrannus T. d. vorax in the LesserAntilles, which is typelocalities and did not evaluateplumage VOLUME 57 (2003) NUMBER 2 149 GrayKingbird was first noted in SouthCar- olina in 1832by J. J. Audubon(Smith and Jackson2002). It wasconsidered byPost and Gauthreaux(1989) to be a "veryrare vagrant andcasual breeder on thecoast." The only recentbreeding record for SouthCarolina is of a pair that summeredat DebidueBeach, GeorgetownCounty, and producedat least onefledgling, which was seen 13 July 1993 (Davis1993). The last prior breeding record forSouth Carolina was in 1896,though a pair wasseen in suitablenesting habitat on Fripp Island,Beaufort County 11-13 May 1984 (McNair and Post 1993). The firstGray Kingbird record for North Carolinawas noted in March 1957 (Funder- burgand Soots1959), and that summer,the speciesapparently nested at Southport village, BrunswickCounty ¾he sightings are chroni- cledby Chamberlain (1957): "A group of Gray Kingbirdsspent some weeks around Southport village.The first was nottxl, June 28, on a w•re, by WatersThompson; on Aug. 21, fourwere presentat thissame site and one of thosewas examinedclosely by CecdAppleberry, who thoughtthat the head shading was not so dark Figure3. AGray Kingbird welloffshore isa rare sight: this bird landed onthe oil-drilling platform Exxon Green Canyon 18, as the birds he had seen in Florida; he sus- some130 km south of the Louisiana coast, on 22 May 2000 and remained through 25May. These platforms, likeremote islands,aremagnets forweary migrants andare good places todetect vagrants. Photograph byBrian L.Sullivan. pectedit mightbe a birdof theyear. Again on the 22nd,three were present (Mrs. A.)." The detailsof the record suggest nesting, especially coloration,including characters said to differ- Statesfrom the Florida panhandle west to M•s- giventhat four birds would be unlikely to be entiate I.. d. vorax. sissippiand north along the Atlantic Coast to togetherin a groupunless as a familyunit, and Vagranttymnnids, like mostvagrant land- Georgia.In Florida,the birdsare especially we suspectthat this group rcpresented a first birds,appear to be consistentlyfrom migra- commonin theKeys. They breed north along North Carolinanesting. Gray Kingbirds tory populationsor taxa(see,