Vol.55, No. • GeneralNotes [3 8 3 the Universityof SaskatchewanField Stationproperty of Fairy Island,Emma Lake, Sas- katchewan (53'30'N, 105'50'W). From 94 females banded as adults on the nest between 1973 and 1982, 44 were recapturedon their nestson 93 occasionsin subsequentyears. Three birds were found dead in their nestboxes, including 786-38111, bandedon 15 June 1974, recapturedin 1975, 1978, 1979, 1980, and 1981 and found freshlydead on 5 fresh eggson 6 June 1982. Another femalewas shot 2 yearsafter banding.From thesedata (Table 1), and by usingthe methoddescribed by Chapmanand Robson(1960), we estimateda minimum annualsurvival rate of 57.8% (SD -- 3.1). This estimateshould be consideredpreliminary becausethe data do not meet the requirementsoutlined by Brownieet al. (1979) and annualbanding and recaptureefforts were unequal.Also, artificial nest structureswere subjectedto extensivedamage by blackbears (Ursus americanus) in some years. Neverthe- less,our estimateof CommonGoldeneye survival does provide additional information for this species.The annual survivalrate for Minnesotagoldeneyes was 63% (Moyle et al. 1964). The reported survivalrates of other seaducks (Mergini) include55.3% for adult femaleBuffleheads (Bucephala albeola) banded in BritishColumbia (Erskine 1971:177) and 63.8% for adult female White-wingedScoters (Melanitta fusca deglandi)banded in Sas- katchewan(Brown and Houston 1982). Adult survivalrates for these 3 seaduck species are higher than for any of the North American dabblingducks summarized by Bellrose (1980). These data are further evidencethat seaducks, like other specieswith deferred maturity,tend to havehigher survivalrates than speciesthat matureat an earlier age. We wishto thank R. B. Owen for his reviewof the manuscript.

LITERATURE CITED BELLROSE,F. C. 1980. Ducks, geese,and swansof North America. StackpoleBooks, Harrisburg,Pennsylvania. BRowN,P. W., ANDC. S. HOVSTON.1982. Longevityand age of maturity of White- wingedScoters. J. Field Ornithol. 53:53-54. B•OWNIE, C., D. R. ANDERSON,K. P. BV•N•AM, AND D. S. ROBSON. 1978. Statistical inferencefrom band recoverydata--A handbook.U.S. Fish Wildl. Serv. Res. Publ. No. 131. C•APMAN,D. G., ANDD. S. ROBSON.1960. The analysisof a catchcurve. Biometrics16: 354-368. E•SKINE,A.j. 1971. Buffleheads.Can. Wildl. Serv. Manage.Ser. No. 4. MOYLE,J. B. (ED.),F. B. LEE,R. L..]ESSEN,N.J. ORDAL,R. I. BENSON,J. P. LINDMEIER, R. E. FARMES,AND g. g. NELSON. 1964. Ducks and land use in Minnesota. Minn. Dept. Conserv.Tech. Bull. 8. PALMER,R. S. (ed.). 1976. Handbookof North Americanbirds. Vol. 3. Yale Univ. Press, New Haven, Connecticut. MAUREENREVER DuWoRs, Departmentof Biology,University of Saskatchewan,Saskatoon, Sas- katchewan,S7N OWO;C. STUARTHOUSTON, 863 UniversityDrive, Saskatoon,Saskatchewan S7N OJS;and PATRICKW. BROWN,College of ForestResources, University of Maine, Orono, Maine 04469. Received16 Nov. 1983; accepted10 May 1984.

Longevityof the American Goldfinch.--Most passerinebirds experiencehigh mor- talityand therefore have short life expectancies(Lack 1954, Dorst 1974). As a result,few individualsof smalltemperate-zone songbird species, living under naturalconditions, are knownto reachages in excessof 7 years(Kennard 1975), but in captivitymay live for 15 yearsor more (Dorst 1974). As part of a continuingstudy of the AmericanGoldfinch (Carduelis tristis) at Guelph, Ontario (Middleton 1979), the nestinghistories of 6 individuallycolor-marked female birds have been recorded for three successiveseasons, 2 for 4 successiveseasons, and one for 5 successiveseasons. These birdswere of unknownage when first captured,and were at least4 and 6 yearsold, respectively,when last encountered.Thus from our records, we had little reasonto believethat free-livingAmerican Goldfinches reach ages in excess 384] GeneralNotes j. FieldOrnithol. Summer 1984

T^BLE 1. Distributionby age and sex of American Goldfinchesrecovered 5 or more yearsafter banding.Data from the filesof the Bird BandingLaboratory, Patuxent Wildlife ResearchCenter, Laurel, Maryland, 1923-1979. Yearsafter Distributionbysex Estimatedby banding Total in file regr•ession t Male Female Unknown Y, Yt

5 24 14 15 53 51.6 6 17 2 8 27 23.7 7 3 2 2 7 10.9 8 2 5 -- 7 5.0 9 .... 2.3 lO 1 -- -- 1 1.1 11 .... 0.5 Totals 47 23 25 95

of 6 years,a statisticfitting with that generallyaccepted for smallsongbir•ls (Kennard 1975). By contrast,one captivemale American Goldfinchis known to have lived for a minimumof 11 years(Phillips 1968). In an attempt to establisha reliable figure for survivalof American Goldfinchesin the Guelphpopulation and thosefrom other partsof North America,we analyzeddata in the bandingfile of the U.S. Fishand Wildlife Service,Laurel, Maryland,through 1979. Data were extracted for all recoveries/recapturesmade a minimum of 5 years after banding;we obtained95 suchrecords (Table 1). The appropriateequation for survival usingthe existingdata is Y, = NS' (seeAndrewartha and Birch 1954, Schemnitz1980), where Y is the number recovered, N is the number banded, S the annual survival rate, and t the number of years sincebanding. By transformingthis equation to In Yt = In N + t In S (C. Faanes,pers. comm.),and performing a regressionwith Y• as dependent and t asindependent variable, the curvein Fig. 1 wasobtained; the valuesof the estimate Y• are givenin Table 1, and the estimatedsurvival rate S = 0.4591 (for malesalone, S = 0.5069 and for males+ unknown sex, S = 0.4539; for females,the result wasnot signif- icant). Four observationsmay be made. First, becausemales have a slightlyhigher survival than females,one wouldexpect more malesto be long-livedthan females(Table 1). The disparitybetween the sexesmay be enhancedby a skewedsex ratio favoring malesin AmericanGoldfinch populations (1.6/ 1, n = 6201, pooleddata for both winter and sum- mer populations).Second, the survivalcurve shows a gradualdecline towards extinction around the 1l th year. Thus adult mortality for the American Goldfinch is steadyas predictedfor birdsby Lack (1954:94) and Ricklefs(1973:450). Third, the data suggest that longevitymay vary for differentpopulations. The survivalrate of 46% aboveis higher than the 36% and 28% we have calculated for male and female American Goldfinches in Ontario and the 36% and 30% for eachsex in Ohio (Middleton and Webb unpublished) and seemshigh by passerinestandards. However, Bray et al. (1979) obtaineda survival rate of 58.5% for adult male Yellow-headedBlackbirds (Xanthocephalus xanthocephalus), andpreviously published survival rates for passerinesare probablyunderestimates (Botkin and Miller 1974). Of the 5 birds in the samplewhich were either banded(2 in Ontario) or recovered(3 in Nova Scotia, Quebec, and Ontario) in Canada, none wasencountered beyond6 yearsfrom banding.Such longevity fits with the data from our color-marked populationat Guelph.By contrast, the 95 birdsencountered 5 or moreyears from banding weregenerally from moresouthern localities (average latitude 40ø4 I'N, averagelongitude 76ø27'W:central Pennsylvania).These data supportthe suggestionthat birds living in rigorousclimates have shorterlife spansthan thosein amenableclimates (Welty 1982). Finally,some free-living American Goldfinches do live beyond7 years,and the potential Vol. 55, No. 3 GeneralNotes [3 8 5

6O

5O

In•//= 7.8569-0.7785t

r= -0.9821

ß

= 20

I0

:1 i 5 6 7 8 9 I0 II Minimum Age (yr) FIGURE 1. Survivorshipcurve for AmericanGoldfinches known to be olderthan 5 years. longevityfor the AmericanGoldfinch, as indicated by both bandingand captive(Phillips 1968) data, appearsto be in the regionof 11 years. We thank the Bird BandingLaboratory for providingus with data on American Goldfinches,and we acknowledgethe work of all banderswho have made this analysis possible.Ed Bailey,Craig Faanes,and Tom Nuddsprovided valuable criticisms of early draftsof the paper.The studywas financially supported by NSERC grant #A6495 made to A. L. A. Middleton.

LITERATURE CITED ANDREWARTHA,H. G., .ANDL. C. BIRCH. 1954. The distribution and abundanceof animals. Univ. ChicagoPress, Chicago and London. BOTK1N,D. B., ANDR. S. MILLER.1974. Mortality ratesand survivalof birds.Am. Nat. 108:181-192. BRAY, O. E., A.M. GAMMELL, AND D. R. ANDERSON. 1979. Survival of Yellow-headed Blackbirdsbanded in North Dakota. Bird-Banding50:252-255. DORST,J. 1974. The life of birds. Vol. 1. Columbia Univ. Press,New York. KENNARD,J. H. 1975. Longevity recordsof North American birds. Bird-Banding46: 55-73. L^cK, D. 1954. The natural regulationof animal numbers.Clarendon Press, Oxford. MIDDLEtON,A. L. A. 1979. Influenceof ageand habitat on reproductionby the American Goldfinch.Ecology 60:418-432. PHII.I.1PS, R. S. 1968. Goldfinchattains age in excessof 11 years.Auk 85:499. RICKLEFS,R. E. 1973. Ecology.Chiron PressInc., Newton, Massachusetts. SCHEMN1TZ,S. D. (ed.). 1980. Wildlife managementtechniques manual. 4th ed. The Wildlife Society,Washington, D.C. 3 8 6] GeneralNotes j. Field Ornithol. Summer 1984

WELTY,J. C. 1982. The life of birds (3rd ed.). W. B. SaundersCo., Toronto. ALEXL. A. M•r)r)LE•rON,Department of Zoology,University of Guelph,Guelph, Ontario, NIG 2WI, Canada,and PmL•PWEBB, 12 High Park Gardens,Toronto, Ontario, M6R IS9, Canada. Received10 July 1983; accepted8 May 1984.

Dome Rebuildingby ClapperRails.--In a typicalClapper Rail (Ralluslongirostris) nest the eggsare held in a shallowbowl suspendedabove the ground by a columnof marshgrass (Spatrina alterniflora). A domeis woven from bladesof livinggrass that extends over the nest,thus concealingthe eggs.Although somehave reported the domeuse as camouflagefrom aerialpredators (Johnson, 1973, Observationson the ecologyand man- agementof northernClapper Rail, Ralluslongisostris crepitans in NassauCounty, New York, Ph.D. diss.Cornell Univ., Ithaca,New York) otherssuggest that it probablyaids to containthe eggswithin the nest during tidal inundation(Andrews, 1980, Nest-related behaviorof the ClapperRail (Ralluslongirostris), Ph.D. diss.,Rutgers Univ., New Bruns- wick, New Jersey). I studiedClapper Rails at Corson'sInlet (nearOcean City, Cape May County,New Jersey)from May to July in 1977 and 1980. To test whether or not these rails would rebuildthe dome,and to examinedependence of rebuildingupon nesting stage, I opened the wovendome abovethe nest cup and folded it back along the outsideof the nest platformat eachof 15 nests.Experimental manipulation was done at lowtide and checked 24 h later for signsof rebuilding.All nestswere located along natural creeks with a mean nest distance(creek side vegetation to nest)of 3.5 m (range: 1.8 to 6.0 m). Mean nest height(ground to nestcup rim) was21.4 cm (range:10 to 33 cm).All nestshad similarly built domes.If 5 or moreblades of grasswere interwoven, the domewas considered rebuilt. Suchmanipulations were done during laying (thosenests having 1-5 eggs),incubation or late laying(those nests having 8-12 eggs),and late incubation(first day an egg was pipped).Experiments were done on 5 nestsfor eachof the 3 nestingstages. Ghi squareanalysis (df = 2, X• = .50, P >. 05) revealedthat the stageof nestingdid not influencedome rebuilding more than wouldbe expectedby chance.Eighty percent (12 of 15 nests)of the dome-manipulatednests were rebuilt within 24 h (thosenot rebuilt included;2 early, and 1 during mid-incubation).Of 3 nestswhere the domeswere not rebuilt, one nestwas abandoned with no eggsfound in the area of the nest,the second waslost to predationof all eggsby crows,and the third nestproceeded through normal hatchingwithout egg lossand withouta dome.--PAuL A. KOSTEN,1217 NewYork Avenue, CapeMay, NewJersey 08204. Received29 Apr. 1983; accepted18 Apr. 1984.

Attackson a Human by a NestingAmerican Kestrel.--Attacks by falconiformeson humansare generallyuncommon and usually are in defenseof nestsor nestingterritories (Brown 1976:130).However, it is not at all unusualfor accipiterslike the Northern Goshawk(Accipiter gentilis) and larger falconssuch as the Peregrine(Falco peregrinus) to strikehumans in defenseof their nests(Craighead and Craighead1956, Snyder1974, Ratcliffe1980:229). In thisnote I reportattacks on a humanintruder by a nestingfemale AmericanKestrel (Falco sparverius). On 21 May 1982, I waschecking a kestrelnest in BooneCounty, Missouri. The nest was5 m highin a hollowbeam at the endof a tool shedand contained 6 nestlingsranging in age from 2 daysto 1 week. Initially both adult kestrelssoared and hovered 10-20 m abovewhile vocalizingincessantly. Suddenly the femalestooped on me in a seriesof 12 successivedives, missing my headby centimeters.The laststoop culminated in the kestrel raking my scalpwith her talons. Her attacksoccurred again on 27 May when I wasstruck 8 times,on 2 June when I bandedthe 6 nestlingsand wasstruck 4 times,and on 14June when I collectedpellets from the nest.The intensityof her aggressionwas less during this last visit and I was struckonly once. In 1983, this femalekestrel repeated her aggressivenest defense, striking me 13