150• P^RKS, Sexing and Aging the Starling Bird-Banding

[Pages:4]148]

P?m/cSse,xinagndAgintgheStarling

BirJduly-Banding

BEV?GEAV.?J,. 1961 Bird Study. New York. J. Wiley & SonsI,nc. 389 pp.

BOYD,E. M. andSH?USE?tJ,. 1954 Nestingand food of the Barn.Owl (Tyto,

alba) in HampshireCounty,MassachusettsA.uk 71: 199-201.

DENNIS,J.V. 1958 Are warblersdecreasing?Aud. Mag. 60: 32-34.

.ELIOT,S. A., JR. 1948 Blue-grayGnatcatcherisn HampshireCounty,Massachu-

setts. Auk 65: 314, 315.

1961 Birds in March. Bird News o/ IVestern Massachusetts. 1: 28-30.

FamnvaDGER, .W. 1960 The changinglevel of the sea. Sci. Amer. 202: 70-79.

[FORBUSHE,. W. 1927 Birds of Massachusettasnd other New EnglandStates.

Vol. 2 Mass.NorwoodPressxlviii q- 461 pp.

JOHNSONG,.P. 1916 Bird; of SpringfieldM, assachuseattnsdvicinity. Spring-

field, Mass. BassetteCo., Revised by S. A. Eliot, 1960.

MasoN, E. A. 1952 Notes from o'er sanctuaries. Arcadia. Mass. Aud. 36: 394.

?

and SHatsn,M. S. 1949 Reporton ConnecticuRt iver Valley co-operative

EveningGrosbeaksurvey. Bird-Band. 20: 169-179.

MassachusetAtsgriculturalExperimenSt tationMeteorologicaOl bservations

1900-1909 MeteorologicalSeriesBull. No. 133-252

1950-1959 Meteorological Series Bull. No. 733-840

MortvasR, .O. 1901 Thebirdsof SpringfieladndvicinityS. pringfieldM,ass.H.J.

? Johnson.

WaL?.acrG, .J. 1959 TheplightoftheBluebirdin Michigan.WilsonBull.71:

192, 193.

ACKNOWLEDGMENTS

Dept. of Zoology.MountIlolvoke College,SouthHadley,Mass. I am sincerelygratefulto ProfessoSr amuelA. Eliot of SmithCollegeand Mr. Edward Mason, Director of Arcadia Sanctuaryfor reading the manuscriptand for

offeringinnumerablevaluablesuggestions.

ReceivedJuly 1, 1961

A CONVENIENT

METHOD

OF SEXING

THE STARLING

By G. H^Pcoo?) P^VK, S

AND AGING

During 1960 the Bird-BandingOfficelaunchedan 18-monthproject for the purposeof testing"the comparativreatesof recoveryof birds bandedwithregularFishandWildlife Servicbeandsandwiththosebearing

a postofficeboxlegend"whichwouldrevealnoconnectiownithanygovernmentaal gencyW. e becameawareof thisprojectwhenwe readthe appeal,publishedin EBBANews (1) andin Bird-Banding(2), for interestedbandersto cooperatien the study.

Hartford'sabundanptopulationof Starlings(St,rnusvulgaris)promi*ed adequatwe orkingmaterialso,rathertardily,we volunteereodurcooperation.On January21, 1961we receiveda supplyof thespeciablands which carriedthe legend,'?Write P. O. Box 66, Bowie,Md. USA," and controbl andswith the standardlegend,'?WriteF & W Serv.Wash.D. C.

USA."

Tb_einstructiosnheetwhichaccompanitehdebandsaskedthatall birds be sexedandaged,if possible.Althoughwe hadhandledp, reviously, morethana thousanidndividualosf thisspeciewsehadnevermademore thana cursoreyffortto sexandagethem. We decidedto takeadvantage

ofthisprojecttotestourownabilityof applyincgertaisnuggestseedxing andagingproceduresT.hispaperisabriefdescriptioonf ourexperience.

We choseto beguidedbythemethoddsescribeidn Bird-Bandinbgy

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PARKSSex, inangdAgintgheStarling

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BrinaKessel(3) andbyDavidE. Davis(4) ratherthanbythatof Alden H. Miller (5) despitethefactthat,in thelatterinstanceth, erecommended operationon the skinof the headis describeads"innocuous."

To determinethe bird'ssex,then,we wouldexaminethe eyesandthe ramiof thelowermandible.If theiriswasfoundto beuniformlydeep brownandtheramibluishtoblackin colorthebirdwouldbeaccepteads a male. If, howevert,hedarkbrowniriswasfoundto beborderedby a lighter-colorreidngandtheramiappearepdinkorcream-colorweedwould

record the bird as a female.

Oncesexedw, e wouldagethe birdsaccordingto Davis' (4) recommendationby measuringthe lengthof the iridescenatreaon the hackle feathersand applyinghis informationthatthismeasuremeinntthe cases

of immature and subadult females is less than 6 min. while in adult females

it is morethan 7 min. Amongthe malesa measuremenotf lessthan 10

min. would characterize the iramatures and subadults while the adults

would measure more than 12 min.

We prepareda metricruleraccordintgo thissameauthor'sinstructions andwenttowork. Tablescrapasndstalepastriefsromthe"reducepdrice" shelfat thechainstoreprovedto beveryappealinbgait,buttheStarlings avoidedourPull-stringP,ottera, ndAll Purposterapssopersistenatlsyto

threaten the success of our effort. When we substituted Chardonneret

traps,howevert,he birdswerecapturedreadilyenough.

With our '?Bowie"bandsandcontrolsarrangedin parallelnumerical sequencewse bandedourcapturesa,sfollows:thefirstbirdwith the first '?Bowie"band,theseconbdirdwiththecontrobl andcarryingtheidentical serialnumberb, ut differingtypicallyfromthe'?Bowie"in itsprefixand legend. The third bird receivedthe second'?Bowie"bandin numerical sequenceth; e fourth,the correspondincgontrol-- and soon until we bandedour 500thStarlingjustastheterminadl ateof theprojectwas approaching.

Becausoef ourabsencferomHartfordduringthe summemr onthsthis studywasnecessardiliyvidedintotwoperiodsn,amelyJ:anuar2y! toJune 9, andNovember6 to Decembe1r8, 1961.As a resultof our inactivity whentheyoungwerenewlyoffthenestsonlythreebirdsweretakenwhich weretooimmatureto haveacquiredthetypicacl haracteristoicfseye,mancliblea, ndhackleiridescenwcehichwesought.

Theirisringwassodefinitelaybsenotr sodistinctlaypparenat,ndagreed sopositivelywith the coincidenrtami colorationt,hat we felt justifiedin sexing487 of our 500 Starlingsunquestionabalysmalesor femalesr,espectively.Threeof the unsexedbirdswerelocallyhatchedyoungsters whichwe judgedtoo youngto be labeledasmaleseventhoughnone showedthe iris ring (nor, of courset,he bluishrami). Observationosf the remainingunsexedtenwereinconclusivceo, nflictingo,r tooindefinite to justifya decisionasto the sexof thebird.

Oncesexedt,henextstepwasto determinteherelativeageof thebird. To accomplisthhisresultwe againfollowedtheDavis(4) recommendation regardingthe measuremenotf the iridescencoen its hacklefeathers. We collecteda pinchof the feathersfromthethroatregionof eachbird andmeasuretdhe lengthof theiridescenatrea,to theneares0t .5 ram.,on severaol f them. Therewasalwaysmoreor lessnormalvariationin these measuremenbtsu,talmoswt ithoutexceptiotnhatvariationwassoslightas

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P^RKSSe,xinagndAgintgheStarling

BirJduly-Banding

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PARKSSex, inagndAgintgheStarling

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to supplyus with a compositpeicturewhichplacedour bird distinctly withinthe measuremecnat tegoriyndicatedin the Kessel(3) description and in Davis' (4) table. The only problemwhichgaveus anytrouble provedto be a ratherminorone. It involvedtheeffecot f varyingconditionsof illuminatiounpontheeasewithwhichwewereableto determine

the actual extent of the iridescence on the feathers.

As we handledmoreandmoreof thesebirdsthe shapeof the hackle feathersbecamesucha significanttrait thatit addeditselfasa sexcharacteristicto the two characterws e had chosento usewhenwe beganour study.Typicahl ackleasrenicelypicturedin Kessel'(s3) Figure1. Since ourexperiencweasspreadoveralmosatnentireyearit isnottobeexpected that all of the featherswe examinedcouldbe describeedxactlyby any singlesetof illustrationsW. e found,howevert,hatthepicturews erecorrectlyrepresentativIef. a criticismof thediagramispermissibwleewould saythat,in thelightof ourobservationpsa,rtA (theadultmalefeather) leavesthereaderwiththeimpressioonf a featherthatisrelativelbyroader thanwascharacteristoicf the extremelyattenuatehacklethatwe collected fromdefinitelyadultmalebirds.

The hacklemeasuremenotfsthe487 sexedStarlinghs avebeenassembled in theaccompanyitnagble. Thedatahavebeenarrangeidn sucha manner asto revealthesignificancoef thismeasuremeinntdeterminintgherelative agesof thebirds. Sincethetableseemcsapableof speakinfgor itselfno furtherdiscussiofnit willbeattemptehdere.

SUMMARY

In spiteof ourlackof priorexperiencweiththeprocedurweesucceeded in sexing487 of the 500Starlingswhichwehandled. Thenwewereable to determinetherelativeagesof 236 of the 273 malesa, nd191 of the214 females.Thismeansthat97.4 percenot f ourStarlingws eresuccessfully sexedand87.7percenot f thesesexedbirdsweresuccessfuallgyedbythe Kessel-Davpisrocedure.Individuavl ariationisn thesizeof theiridescent hackleareaswassufficientlgyreatin someinstancetso causetheirmeasurementsto fall outsidethelimitsassociatewdith definiteagegroups.This factaccountfsor thatrelativelysmallpercentagoef birdswhichwe were obligedto classifyas"agenotdetermined."

CONCLUSION

We havefoundthe Kessel-Davimsethodto be an adequatelsyimple andsatisfactopryrocedurfeor sexingandagingthe specieSsturnusvulgaris. Evenrelativeliynexperiencoepderatorwshowill applythismethod consistentslyhouldbe ableto sexandagethesebirdswith accuracaynd, in sodoing,theywill addmeasurabltyo thevalueof theirrecordsn, otto mentionthenewinteresat ndthe greatersatisfactiotnheywill experience astheyhandlethiscommonb,utveryintriguingb, ird.

REFERENCES

(1) EBBA News 23(4): 78. (2) Bird-Banding31(3): 170. (3) KESSELB, RIN^. 1951. Criteriafor sexingandagingEuropeanStarlings(Stur-

nusvulgaris). Bird-Banding22(1): 16-23. (4) DAVIS,DAWD E. 1960. Commentson the migration of Starlingsin Eastern

United States.Bird-Banding31(4): 216-219. ?5) MILLER,ALDENH. 1946. A methodof determiningthe ageof live passefine

birds. Bird-Banding17(1): 33-35. 99 WarrentonAvenue,Hartford, Connecticut.

Received March, 1962

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