An Influx of Common Ringed Plovers (<I>Charadrius Hiaticula</I>) in Southern Newfoundland in Autumn 2006
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Aninflux of Common Ringed Plovers (Oh iushi t'cu )in southern Newfoundlandin autumn 006 JAREDCLARKE * BASIC MEDICAL SCIENCES (NEUROSCIENCE), FACULTYOF MEDICINE ß MEMORIAL UNIVERSITY OFNEWFOUNDLAND * ST.JOHN'S, NEWFOUNDLAND A1B3V6 ß (EMAIL:[email protected]) DAVEBROWN ß 7 JEFFERS DRIVE ß MOUNT PEARL, NEWFOUNDLAND A1N2V9 ß (BALL:dave.browneC_•gmail.com) Abstract Meadows (24-28 August 24 1980; B. oenanthe) in eastern Canada and the At- The fall migrationof 2006 saw the ap- Mactavish) and an adult at Bellevue lantic coast of North America--another pearance of four Common Ringed Beach(14-16 August 2001; E Linegar commonbreeding species in Greenland Plovers (Charadrius hiaticula) in New- and others). The only documented and Baffin Island. foundland, Canada. This was twice the recordsof thespecies from the Lower 48 previousnumber of sightingsfor the United Statesare from Maine, an adult on Field encounters provinceand an unprecedentedinflux the SouthLubec Flats 26 August-5Sep- Thefirst Common Ringed Plover of 2006, for eastern North America south of the tember 2003 (Ellison and Martin 2004) an adult(probably male), was discovered breedingrange. This paper documents and from Massachusetts (Veit and Pe- on a tidal beachat Trepasseyon 20 Au- theserecords and highlights the features tersen 1993). gust(D. Brown,J. Harding);this individ- usedto identifythis cryptic and probab b During a four-weekperiod (20 Au- ual continuedto be seensporadically overlookedspecies. gust-17September 2006), four Common throughthe following nine days. The sec- RingedPlovers were observedat loca- ond individual, an adult male, was found Introduction tions in southeastern Newfoundland: 29 Augustat BearCove, near the com- CommonRinged Plover, though primari- threeadults in worn breedingplumage munityof Renews(K. Knowles,S. Dex- ly a Eurasianspecies, breeds in western andone juvenile. All fourbirds were well tar). This bird was well photographed Alaska, Greenland, and in Arctic Canada documentedwith photographs,and two and documented over the next hour but on the northeastern coasts of Baffin and were seen by eight or more observers. was not relocated. Almost three weeks Ellesmere Islands (Alderfer 2006). In The prevailingweather patterns in the later,on 16 September,a third Common easternNorth America, Common Ringed days and weeks leading up to these RingedPlover was discovered on a small Ploveris rarelyrecorded outside of its recordswere characterizedby strong boatslipway at St. ShotCs(D. Brown,J. known breedingrange. Prior to 2006, northeasterlywinds. Coincident with the Clarke). This bird, an adult (and pre- therewere only two records for theisland plover observationswere numerous sumedfemale), was observed by a totalof of Newfoundland: an adult at 1LAnseaux records of Northern Wheatear (Oenanthe eightbirders over the next few hours. Juvenile(left) and adult Common Ringed Plovers, St.Shotts, Newfoundland, 17September 2006. Photo•]raphbyJared Clarke. 170 NORTH AMERICAN BIRDS COMMONRINGEDPLOVERS INSOUTHERN NEWFOUNDLAND 1 All three adult CommonRinged Ploversassociated with Semipalmat- ed Plovers(C. semipalmatus)and immediatelystood out amongtheir congenersby virtueof their paler, sandierupperparts, thicker breast bands,and distinctfacial patterns, with more extensive white behind theeye. On average, the psammodro- '• ma subspeciesof CommonRinged Plover, which breeds in eastern North America,is largerand per- hapspaler above than Siberian tun- drae and Europeanhiatacula, and these distinctions serve to set them apartstill morefrom Semipalmated Plover (Paulson 2005). The most strikingfeature of the adultplovers was the thick, black breast band, most notable when the birds were standingand alert. While band thickness is variable between indi- viduals,and its apparentthickness Figure1. Adult (probable male) Common Ringed PIover, Trepassey, 20-29(here 20) August 2006. Note the pale brown upperparts, canchange with posturein all belt- verythick black breast band, broad white supercilium extending well behind the eye, and lack of pale orbital ring (observed asblack in ed ploverspecies (Sibley 2000), a thefield). The lower edge ofthe dark"mask" meetsthe bill precisely atthe gape. Photograph byKen gnowles. typical Common Ringed Plover showsa notablythicker band than a typicalSemipalmated Plover. Final- ly, comparedto the adjacentSemi- palmatedPlovers, these adult Com- mon RingedPlovers had a more contrastingdark face "mask,"offset by an extensive white forehead patchand supercilium(the use of "supercilium"here indicates either a completeor a partial supercilium, one that extendsonly posteriorly fromabove the eye). The features noted above were morethan enough tomerit further • scrutiny,but theywere not enough to confirm an identification of Com- monRinged Plover (see Dunn 1993, Lakin and Rylands1997, Alderfer 2006).Fortunately, closer inspection of the birds and excellentphoto- graphsallowed for confirmationof three additional characteristics: de- Figure2. Adultmale Common Ringed Plover, Bear Cove, Newfoundland, 29August 2006. Note the very thick black breast band. tailsof thefacial pattern, orbital ring Thedistinctive facialpattern includes broad black auriculars, offsetting anextensive white supercilium. Thedark orbital ring and color,and lack of webbingbetween long,tapered billare also typical ofCommon Ringed Plover. Photograph byKen I(nowles. the inner toes.All threeplovers ex- hibiteda more contrastingmask than the white of the throat extended to a maleSemipalmated Plovers typically have adultSemipalmated Plovers, including a pointabove the gape and the junction of a faintwhitish mark behind the eye; adult broadear patch(auricular) and adjacent the black lores with the bill was thus al- femalesmay have a moreextensive post- area of black in the lower lores. This area waysabove the gape--a subtlebut im- ocularmark (or partialsupercilium) than of blackremained evenly wide toward the portantdistinction from Common Ringed males, but the auriculars are browner, bill, so that the loweredge of the black in all plumages.A thickwhite supereili- creatingless contrastthan seen in an terminatedprecisely at the gape.By con- um extendedprominently behind the eye adult CommonRinged Plover. On each trast, the dark in the lower lores of the (and in mostcases also above the eye), bird, the whiteforehead patch was large SemipalmatedPlovers appeared invari- borderingthe black auriculars,in all and taperedto a prominentpoint below ablymore "pinched together," such that adult CommonRinged Plovers. Adult the eye. This featureis typicalof Com- VOLUME 61 (2007) ß NUMBER 1 171 COMMONRINGED PLOVERS IN SOUTHERNNEWFOUNDLAND man RingedPlover but not of Semi- Photographsand scopeviews showed rings.More importantly, it was confirmed palmatedPlover, which generally shows a thatall threebirds had veryinconspicu- (andphotographically documented) that smallerforehead patch with a straighter ousdark orbital rings; adult Semipalmat- all threebirds had very minimal webbing rear border. ed Plovershave yellow-orangeorbital between the inner toes and none at all between the outer toes. The most reli- ablecharacteristic for distinguishingbe- tweenCommon Ringed and Semipalmat- ed Ploversis probablythe more extensive webbing(palmation) between the front toesof Semipalmated(but especiallythe outer toes),which lendsthe speciesits name.Two of theadult Common Ringed Ploverswere heard to givethe diagnostic tODD-Illcall on several occasions,a call thatis moredrawn out, melancholy;and flutelikethan the risingchu-wee call of SemipalmatedPlover. Upon returningto studyand photo- graphthe adult Common Ringed Plover at St. Shottgon 17 September,the au- thors discovereda juvenile--thus a fourth bird. The identification of Com- mon RingedPlover is juvenalplumage has only recently been illuminated (Mullarney1991), but it is now consid- ered feasible and is treated in most North Americanfield guidesthat treat Common Ringed Plover (e.g., Sibley 2000,Brinkley 2007). The bird's slightly largersize, paler upperparts,and thick broken breast band first drew our atten- lion. We were able to gel extremely closelooks at the feet (60x scopeviews at less than 5 m), which confirmed the virtuallack of webbtngbetween the out- er toes and thus identification of the in- dividualas a CommonRinged Plover. Unobstructedviews of thefeet were pos- siblebecause the bird wasstanding on a woodenslipway, as opposed to a muddy or sandyterrain. Close inspection and numerous photographsalso showed that the loweredge of the maskwas not "pinched"and did indeed meet the gape,a featureindicative of Common Ringed in both juvenal and adult plumages.Whereas all the nearbyjuve- nile SemipalmatedPlovers were found to have pale or orange-yelloworbital rings, this individualhad a uniformly black ring visible onl), at very close rangewith telescopes.This bird was lat- er seen in close association with the Figure3. Adult (probable female) Common Ringed Plover, St.Short's, Newfoundland, 16-17September 2006. (3A) This adult CommonRinged Plover, the two individualwasnotably larger and paler than nearby Semipalmated Plovers. Note the lack of visible orbital ring and how even posingtogether for photographs thelower edge of the mask (broad dar• lower Ioral area) meets the bill precisely atthe gape. The white forehead patch (perhapsa firstfor easternNorth Amer- (orftonUet) extends below the eye in a prominent point, typical ofthis species. Photograph byPaul Lmegar. (3B) While ica away from the breedinggrounds: oftendifficult toobserve inthe field, the virtual lack