The First Mangrove Swallow Recorded in the United States
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! ! _Lit INTRODUCTION ternwith a one-laneunsurfaced road on top, PaulW. Sykes, Jr. TheSpace Coast Birding and Wildlife Festival makeup thewetland part of thefacility (Fig- USGSPatuxent Wildlife Research Center was held at Titusville, Brevard County, ures1 and2). Theimpoundments comprise a Floridaon 13-17 November2002. During total of 57 hectares(140 acres),are kept WarnellSchool of ForestResources thebirding competition on thelast day of the floodedmuch of the time,and presen]an festival,the CanadianTeam reported seeing openexpanse of shallowwater in an other- severaldistant swallows at BrevardCountyõ wisexeric landscape. Patches of emergent TheUniversity ofGeorgia SouthCentral Regional Wastewater Treat- freshwatervegetation form mosaicsacross ment Facility known as Viera Wetlands. openwater within each impoundment and in Athens,Georgia 30602-2152 They thought these were either Cliff theshallows along the dikes. A fewtrees and (Petrochelidonpyrrhonota) or Cave(P fulva) aquaticshrubs are scattered across these wet- (eraall:[email protected]) Swallows. lands. Followinghis participationat the festival, At about 0830 E5I on the 18th, Gardler Gardler looked for the swallows on 18 stoppedon the southmostdike of Cell 1 LynS. Atherton November. The man-made Viera Wetlands (Figure2) to observeswallows foraging low arewell knownfor waders,waterfowl, rap- over the water and flyinginto the strong 1100Pinelias Bayway, I-3 tors, shorebirds,and open-countrypasser- north-to-northwestwind. Ihe groupcon- ines. The facilityis locatedin southernBre- sistedof Iree (Tachycinetabicolor), Northern TierraVerde, Florida 33715 vard County(28 ø 17' N, 80ø 46' W) at the Rough-winged(Stelgidopteryx serripennis), westend of WickhamRoad (County Road and CaveSwallows. Among this collection (eraall:[email protected]) 509), and about6.4 km north of LakeWash- of swallowswas one with a white rump ingtonin the formerlyextensive freshwater patch,dark upperparts with a greenishcast, marshsystem of theSt. Johns River. This wet- andwhitish underparts. It did not havethe MurrayGardler land is surroundedby pastures,sod farms, facialpattern or whiteflank patches of a Vio- citrusgroves, and row-crops. Five impound- let-greenSwallow (T. thalassina).Reference 9400 MerriweatherDrive mencs(cells), surrounded by a low dikesys- materialsat the site were limited, and obser- Brooksville,Florida 34613 (email:[email protected]) JohnH. Hintermister,V 2522 NW 156thAvenue Gainesville,Florida 32609 (email:[email protected]) Figure1. Typical habitat at Viera Wetlands, Brevard County, Florida. Photograph byBrooks H.Atherton. 4 NORTH AMERICAN BIRDS vations were terminated about 1000 EST. Severalmembers of theFlorida birding com- munitywere immediatdy contacted, and the newsquickly spread. By19 November, most observers had con- cludedthat the bird was probably a Mangrove Swallow(Tachycineta albifinea), but its iden- tificationwas not certain. The Mangrove Swallowof Middle America,White-winged Swallow (T. albiventer)of northern and cen- tral SouthAmerica, Iumbes Swallow (T. stolz- mannOof the northwesterncoast of South America(a splitfrom the Mangrove Swallow basedupon differences in plumage color and pattern,morphometrics, nest construction, vocalizations,and distribution [Robbins et al 1997] and treatedas a full speciesin recent literature [Clements2000, Ridgely and Greenfield2001, Clementsand Shany2001, Dickinson2003]), White-rumpedSwallow (T. leucorrhoa)of southeasternSouth Amer- ica,Chilean Swallow (T. leucopyga)of south- ernSouth America, and the widespread Com- mon House-Martin(Delichon urNca) of the Old Worldare similar in appearance,all haw Figure2. Aerialview of Viera Wetlands atthe Rrevard County South Central Regional Wastewater ing prominentwhite rump patches (Turner TreatmentFacility. The Mangrove Swallow was most often seen in the southern part of Cell andRose 1989; see ranges in Figure3). We Numbers1 and 2, locatedinthe lower right and left of this map, respectively. werequickly able to eliminatefour of thesix •hotographicmapcourtesy of•revard Count• South Central Regional Wastewater Treatment FacJli•. speciesbased on colorof the upperparts and/orlack of whitesupraloral streak, leawng 38 MangroveSwallows (31 adults,7 •mma- Rough-wingedSwallow, up to 12 CaveSwal- onlythe Mangrove and the White-rumped in tures [HY]; 22 males, 16 females)and 24 lows(with palerumps and underparts; pre- contention. White-rumpedSwallows (21 adults,3 irama- sumedto be oneof theMexican subspecies), Ihe VieraWetlands bird, an adultin fresh tures[HYI; 14 males,10 females).The spec- and 5+ Barn Swallows(HiTundo rustlea). The plumage(hatch year [HY] birds have drab imensexamined represent a broad temporal majorityof theobservations were of thebird gray-brownupperparts rather than the glossy andgeogtraphic spread for the two species. Of in flight,although on severaloccasions it was greenof theadults), was present through 25 thespecfinens, 45 werecollected in fall (15 perchedat a distanceof approximately50 m November,during which time it wasseen by Augustthrough 15 December),23 Mangrove at heightsof 1 to 3 m abovethe water surface manyobservers. How long the bird had actu- and22 White-rumped(austral spring for the on dead shrubs and short dead stubs. On 20 allybeen present is unknown.Photographs latter).A smallsample of TreeSwallow spec- November,the swallowwas photographed of the swallow were taken on 18 and 20 imens was also examined at the GMNH. perchednear the topof a deadtree at a dis- November. From 19 November onward, a Selectedspecimens were photographed for tanceof approximately 60m and at a heightof numberof photographswere posted on web- comparisonand to show some of therange in 14 m. It wasseen in directcomparison with sitesand attached to emailsaccompanied by variationof certainfeatures within a species. Cave Swallowsat leastonce, but most of the muchdiscussion as to the correctidentity of Mass and selected linear measurements were timeit wasseen in closecomparison (often this swallow. takenfrom published sources on fivespecies within a meter)with TreeSwallows, flying andused to developa tablefor comparison. into the wind as the birdsaerial-foraged for METHODS Additional linear measurements were taken insects.Observations of the flyingbird were Thedescription we present is based upon our fromspecimen material on loan.More meas- made from the dikes w•th 10x binoculars, notestaken in the field, commentsof others urementswere, upon request, received from sometimesas close as 4 m, butgenerally at 10 who alsostudied the swallow,and photo- theAcademy of NaturalSciences of Philadel- m orgreater under good lighting conditions of graphsof the bird taken at the site. To clarify phia(ANSP; Matt Sharp,pers. comm.), the clearto partlycloudy skies, mild tempera- a numberof questionsnot available from the LosAngeles County Museum (LACM; Kim- tures,and winds from the north-northwestof literature,on websites,or in publishedpho- ball Garrett,pets. comm.), and the NMNH 5-18k.p.h. Thebird often foraged just above tographsand illustrations, a series of speci- (RogerClapp, pets. comm.). Sharp, Garrett, the water surfacenear the dike, providing mens was obtained on short-term loan from and Clappalso provided comments about unobstructedviews of theentire upperparts in the AmericanMuseum of Natural History plumagesof specimens. directsunlight, as well as sideand frontal (AMNH; n=20), theField Museum of Natural views.In foraging,it flewupwind a distance History(FMNH; n=21), the Museumof VIEWINGCONDITIONS andthen circled back. Ihese flights ranged in ComparativeZoology (MCZ; n=13) at Har- Ihe Viera Wetlandsswallow was generally estimatedheights above water from 15 cmto vard,and the U.S. NationalMuseum of Nat- seenin thesouthern portton of Cell 1 (13.7 12m. Whenperched, it wasstudied with 20- ural History(NMNH; n=8), all temporarily hectaresor 33.8 acres)and Cell 2, andflying 60xzoom scopes and through the talephoto housedat the GeorgiaMuseum of Natural overthe pastureto the southof thesetwo lensof cameras.The bird woulddisappear History(GMNH) at theUniversity of Geor- areas. Otherswallows present in the area fromview for long pertods and then suddenly gia,Athens. Specimens on loanconsisted of were 20+ Iree Swallows, one Northern reappear. VOLUME 58 (2004) - NUMBER 1 5 Table1. Comparisonofbody mass and selected linear measurements ofadults offive species ofswallows asa general guide tosize 1 Species(mean/sample size/range, exceptfor total length) 2 TreeSwallow Mangrove White-rumped Violet-green CaveSwallow Swallow Swallow Swallow Parameters2 (T.bicolor) (T.dbiline•) (T.leucorrho•) (T.•hd•ssin•) (œe•rochelidonfulv•) Sources Mass(g)3 Both 20.1/82/15.6-25.4a 15.0/18/14-16.5b 9.0/-/17.0-21.0a 20.4/25/18.4-22.3a Male 14.4/16/13.0-16.3a aDunning1984 Female 13.9/15/12.5-15.2a bB.Stutchbury pers.comm. TotalLength cm(inches) 13(5) 11(4.25) 13(5) 12-13(4.75-5) 12(4.75) Tumer&Rose 1989 WingLength 4 (ram) Male 119.3/61/114-125a 97.3/58/90-105 b 115.7/22/105-122 b 113.9/84/-c 112.3/640/-d aRobertsonetal. 1992 Female 115.3/99/110-121a 95.1/36/90-100 b 114.4/14/108-123b 107.9/37/-c 111.9/823/--d bThispaper; from museumskins CBrownetal. 1992 dWest1995 TailLength 5 54.2/--/48-60a 37.6/38/32-41b 46.9/38/40_55b 49.4/_/45_55a 44.5/_/42_48a aTumer& Rose1989 (ram) bThispaper; from museumskins DepthofTail 6 8.7/-/7-12a 4.5/71/2-9b 5.0/32/2-7b 8.4/-/5-10a aTurner& Rose 1989 Fork(mm) bThispaper; from museumskins WidthofRump 7 17.4/47/10-23 16.3/32/8-22 Thispaper; from Patch(mm) museumskins Tipof Tail to Posterior 28.9/40/23-36