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Incomplete Flight Molt and Age in Certain North American Non-

Peter Pyle Point Reyes Observatory 4990 Shoreline Highway SUnson Beach CA 94970

ABSTRACT INTRODUCTION

Based on specimen examination, informationis The timing,location and extentof moltsin North presented on incomplete or arrested prebasic Americanbirds are remarkablyunderstudied, given flight-feather molts, and differences between their basic importanceto avian biology(Rohwer juvenal and adult flight , in North Ameri- andManning 1990, Thompson and Leu 1994). This can pigeons,doves (),, road- especiallyseems true of the "near-passerines" runners, anis (Cuculidae), nightjars (Capri- (dovesthrough in the sequenceof mulgidae), swifts (Apodidae), the American Ornithologist's Union checklist (Trogonidae),and kingfishers(AIcedinidae). Indi- [1983]).Generally it has been assumedthat re- vidualsof mostof these familiesregularly (but not placementof flightfeathers (here definedas the always) retain flight-feathersfor one or more an- primaries,primary coverts, secondaries, and rec- nual cycles,until a subsequentprebasic molt. Re- trices)in these families,whether it occursduring tained flightfeathers most often includethe outer the first or the adult prebasic molt, is complete secondaries,although in some familiesor species, (Forbush1927, Bent 1932-1940, Roberts1955, primaries, primary coverts and/or rectrices may Wood 1969, Oberholser1974). But in many near- also be retained. In certain families or species passerinesthese moltsare incomplete,with one (groupA) flightfeathers are typicallyreplaced dur- to manyflight feathers, especially among the sec- ing the first prebasic molt, juvenal feathers being ondariesand primarycoverts, typically retained retained until the second prebasic molt, whereas through one or more molt cycles (Test 1945, in others (group B) flightfeathers are not typically Rohwer1971, Forsman1981, Cramp 1985, Evans replaced until the second prebasic molt, juvenal and Rosenfield1987, Baker 1993). Whilesporadic feathersbeing retained until the thirdprebasic molt. informationexists on retainedflight feathers in a In both of these groupsadult featherscan also be few species, especially in Europe, molt in most (but are not always) retained during subsequent NorthAmerican near-passerines has receivedlittle prebasicmolts. Four flight-feather patterns are thus or no attention since that of the earlier, general found in non-moltingbirds: uniformjuvenal, uni- works. form adult, mixed adult and juvenal, and mixed re- placedand retainedadult feathers. Assuming that While examiningmuseum specimens for informa- retainedjuvenal and adult feathers can be distin- tion on molt and ageing criteria, I foundthat indi- guished,many birdsof group A (pigeons,doves, viduals of most near-passerinespecies retained cuckoos, and anis) can be reliably flight feathers regularly for more than one year, aged throughat least theirsecond year, and many and that retention patterns and differences be- birdsof group B (nightjars,trogons and the larger tweenjuvenal and "adult"(definitive or non-juvenal) kingfishers)can be agedthough at leasttheir third featherscould be used to reliablyage these indi- year. viduals, in some cases up to their third or fourth year of life.

Jan.-Mar. North American Bird Bander .Page 15 The variablemolts and complexageing criteriaof RESULTS AND DISCUSSION , ,and woodpeckerswill be de- tailedelsewhere. Here I summarizefindings in the Near-passerinesappear to have a single annual otherNorth American near- families. molt that can occur on the summer grounds, the winter grounds,or both. Individualsof most spe- METHODS cies follow the same general sequence of flight- featherreplacement. Except in hummingbirds(Pyle Specimenshoused at the CaliforniaAcademy of et al. manuscript),and cuckoos and kingfishers Sciences(CAS), San Francisco,Museum of Ver- (see below), molt of the primariesstarts with the tebrate Zoology (MVZ), University of California, innermost,pl, and continuesdistally to the outer- Berkeley, and Point Reyes Bird Observatory most,p10. Primary-covertreplacement in all fami- (PRBO), Stinson Beach, California, were exam- lies exceptwoodpeckers (see Pyle and Howell in ined. On each specimen the flight feathers were press) and kingfishers(see below) usually corre- carefullystudied (see Rohwer 1971) for evidence spondswith that of the primaries.Replacement of of incompletereplacement or for differencesin the secondaries typically proceeds both distally colorpattern, shape and/or wear betweenjuvenal fromthe innermost("tertials") and, a bit later,proxi- and adult feathers. that were collected in ac- mally from the outermost (sl) such that the last tive molt were noted, and for other specimensall secondariesreplaced are often amongs2-s7 (typi- retainedflight feathers were recordedby position cally,s3-s4). Replacementof the rectricescan be in the or . variable and often proceeds irregularly,finishing with feathers among r2-r4. In many species the Specimenswere assignedage codesfollowing the sequenceof replacementcan be protractedand/ calendar-basedsystem of the Bird BandingLabo- or suspended(see below)during migration or win- ratory(Canadian Service [CWS] and U.S. ter, not being completeduntil spring. Fish and WildlifeService [FWS] 1991). Codes in- cluded: U/AHY for a bird of unknownage; HY/SY Retentionof flight feathers resultswhen the molt and AHY/ASY for birds in and beyond their first sequence does not complete before the next an- basicplumage, respectively; and SY/TY andASY/ nual cycle, unmolted feathers being held at least ATY for birds in and beyond their 2nd basic plum- untilcommencement of the next prebasicmolt. This age. In each case the codes representbirds in the has been termed an "arrested"or "abridged"molt one-year period between completionof molts(of- (see Ginn and Melville 1983, Norman 1991); as ten October to September);the code before the opposed to "suspended"molt, in which replace- slash applies until the end of the calendar year ment resumesafter migrationor winter but before (31 December) and the code after the slash ap- the next molt cycle. Thus, during the first flight- plies between thebeginning of the year (1 Janu- feathermolt, retained juvenal feathers often include ary) and the next molt. Primaries(p1-p10) and rec- the outermostprimaries, secondaries among s2- trices (rl-r6) were numbered distally (outward or s7, and/or rectricesamong r2-r4. Juvenal feath- away from the body) and secondaries (sl-s12) ers are usuallyretained symmetrically in bothwings proximally(inward or towardthe body). and both sides of the tail, or at most differ by one or twofeathers. These juvenal feathers may or may Terminologyof molt, plumagesand feather gen- not be the first replacedduring the next molt (see erationsfollows Humphrey and Parkes (1959; see Baker 1993: 23-24); as a consequence,molt se- also Thompsonand Leu 1994). Generationsof quences in adults can be irregular and retained feathersand plumagessubsequent to fledgingare feathersare less-oftensymmetrical. Both juvenal termed juvenal, 1st basic, 2nd basic, etc., while and adult flight feathers may or may not be re- adult feathers, plumagesand birds refer to those tained, hence four molt-retentionpattern catego- that are at least 1st basic in age (i.e., are not ries can be defined: uniform juvenal feathers, juvenal),but otherwiseare of unknownage. mixed juvenal and adult feathers, uniform adult feathers,and mixed replacedand retaineddefini- tive feathers(Figure 1).

Page 16 North American Bird Bander Vol. 20 No. 1 A

C D,

Figure1. Generalizedrepresentation of fourretention patterns found in secondariesof near-passerines uniformjuvenal feathem (A), uniformadult feathem (B), mixedadult and juvenal feathem (C), and mixed replacedand retainedadult feathem (D). Note that juvenalsecondaries usually differ from those of adultsin beingnarrower, more tapered at the tip,and contrastingmore markedly in colorand wear with replacedfeathers, while retained adult feathem contrast less with replaced feathem. Retained juvenal feathemusually occur among s2-s7 and are oftenconsecutive and symmetricalin bothwings, whereas retainedadult secondaries can occurthroughout the wing,are oftennot consecutive,and are less fre- quentlysymmetrical in bothwings. North American pigeons, doves, cuckoos, roadrunners, and aniscan be agedHY/SY (patterns A andC), U/AHY(B), or AHY/ASY (D); while North American nightjars, trogons and Beltedand Ringedkingfishers can be agedHY/SY (A), AHY/ASY (B), SY/TY(C), or ASY/ATY(D). See text for more details.

Jan.-Mar. North American Bird Bander Page 17 Assumingthat juvenal and adult feathers can be secondarieswere less frequent in the collections distinguished, and depending on when replace- (9% of White-wingedDoves, Z. asiatica,and 6% ment of juvenal flightfeathers typically commences of MourningDoves, Z. macroura),and no speci- (i.e., duringthe firstor secondprebasic molt), birds mens were found with retained adult secondaries. with retained flight feathers can be aged more ac- As in Columba,retained juvenal secondaries were curatelyor to a later age categorythan thosewith amongs4-s6 (e.g., Aprilspecimen White-winged uniformadult flight feathers (see Figure 1). Molt Dove CAS31444 and May specimen Mourning patterns within each near-passerine family are Dove CAS32158), and specimenswith these were summarized as follows: assignedage code SY.

COLUMBIDAE I could not confirmage-specific differences in the In pigeons and doves, flight-featherreplacement emarginationof p6-p8in the IncaDove (Columbina occursduring both the firstand the adultprebasic inca),as mentionedby Tweit (1986) and Mueller molts. In North America it is protracted, can be (1993). Emarginationon p6-p9 appears to aver- suspended and, due to year-round breeding in age deeper on adultthan on juvenalfeathers, but some southern populations,can occur in at least overlap between the age groups in this feature a small proportionof birds at almost any time of probablyrenders it difficultto usefor ageing single year (CWS and FWS 1991, and references birds. I found,however, that juvenal and adult pri- therein).These factorsmake it difficultto separate mary coverts in this species and in Common retained feathers from those that are about to be Ground-Dove(C. passerina)differed in color pat- moltedor that were replacedbefore a suspension (Figure 2), andthat this was muchmore help- of molt occurred. Nevertheless, individuals of most ful in ageing. species appear to retain flight feathers until the secondprebasic molt, especially among the middle Figure 2. Juvenal and adult primary covert pat- secondaries. Unless as noted below, retention of in Columbina doves. Note that the rufous primaries and/or rectrices was less common or color of the base of these feathers averages paler more difficult to detect. in juvenals than than in adults.

A small-to-moderate proportion of non-molting, spring-summerRed-billed (Columbaflavirostris) and Band-tailed(C. fasciata)pigeons were found that had apparentlyretained juvenal secondaries, either s6 only, s5-s6, or s4-s6. Examples include Red-billedPigeon MVZ98186 collectedin August with juvenal s5 and s6 of both retainedand veryworn, and Band-tailedPigeon CAS39090 col- Juvenal Adult lected in July also having retaineds5 and s6 on both wings as juvenal feathers. These were as- signedage code SY.Apparent retained adult feath- ers also were foundin specimensof Columba,for Juvenalinner secondaries (s5-sll) also had white example,Red-billed Pigeon MVZ101592, collected tips or cornerswhereas these featherswere uni- in Texas in May, had retainedwhat appearedto formly brown in adults. Many, if not all, HY/SY be adult secondariess2-s3 and s6 in the rightwing Columbina specimens had suspended flight and s2 and s6 in the left wing, and was tentatively feathermolt into winter and spring (see Tweit 1986), aged ASY (see Figure 1). Becauseof year-round andsome HY/SYs(e.g. Junespecimens Inca Dove breeding and suspensionof molts in these spe- MVZ135416 and Common Ground-Dove cies, however,more study is warranted before age CAS39110) appeared to have arrested the molt, code ASY can be reliablyassigned, based solely retainingjuvenal flight feathers until the second on retention patterns. prebasicmolt. Typically,HY/SYs from October through at least March or April still retained the Non-moltingZenaida doves with retainedjuvenal outer 2-5 juvenal primaries(among p6-p10), their

Page 18 North American Bird Bander Vol. 20 No. 1 corresponding,juvenal primary coverts (Figure 2), withless distinct pale tipsthan are foundon adult and 1-6 secondariesamong s2-s8. Adultprebasic rectrices(see NationalGeographic Society 1987: molts seemed more often completeand confined 237). The pale tips on the juvenalsecondaries, to fall/early winter; however, birds with apparent found in Black-billedand Mangrove (C. minor) retainedadult secondaries (e.g., March Inca Dove cuckoos but not in Yellow-billed (Nolan CAS34915 witholder adult s2 and s4-s7) were also 1975, thisstudy) had worn off by the firstsummer found. Based on molt patterns and the above- in two of the fourspecimens; thus, retained sec- mentioned differencesbetween juvenal and adult ondarieswithout pale tips were not necessarily flightfeathers, most HY/SYs and, tentatively,some adult feathers. AHY/ASYs could be aged through March, with at least some SYs and possiblysome ASYs reliably Nine of 125 Yellow-billed Cuckoos had retained aged throughJune or later.Birds with uniformadult flightfeathers, including roughly equal proportions featherscould probably be agedAHY/ASYthrough from easternand westernpopulations. Seven of at least February,but this needs confirmation,es- these(e.g., CAS45001and MVZ169435),which peciallyin populationswith a prolongedbreeding had retained1-4 secondariesamong s2-s8, could season. More study on skull pneumatizationpat- not be confidentlyaged due to the difficultyin dis- terns in Columbinadoves (see Johnston1962) may tinguishingretained juvenal from retainedadult assist in our understandingof molt patterns and secondariesin thisspecies (see below).The two ageing in this genus. otherspecimens (MVZ106985 and MVZ124369) had also retained4 rectriceseach (among r2-r5). Moltretention patterns and ageingcriteria in White- These worn feathers which contrasted with the rest tipped Dove (Leptotilaverrauxi) appear similarto of the tail, were broad, truncateand showed the those of Columba,except that juvenalprimary co- distinctwhite tips of definitivefeathers (see Na- verts are washed rufous whereas adult c6verts are tionalGeographic Society 1987: 237). These birds brown, and this assisted with ageing. couldbe aged ASY. A comparisonof retained juvenalsecondaries on the Black-billedCuckoos CUCULIDAE with retained adult secondaries on the Yellow-billed Flight feathers in North American Cuculidae are Cuckoos revealed that the adult feathers were typicallyreplaced duringboth the first and subse- slightlybroader and contrastedless in wear with quent prebasic molts and, in migratoryspecies, replacedsecondaries than did the retained juvenal replacementoccurs on the winter grounds.Unlike feathers. But these distinctionswere slight, hence, other near-passerines,the sequence of replace- ageingspring-summer birds by retainedsecond- ment of primariesand secondariesin cuckooscan aries only is not recommendedunless (in some be irregular, with two or more series of feathers SY Black-billedand Mangrovecuckoos) the sec- being molted alternatelyor in both directionsfrom ondarieshave pale tips still remaining.It is pos- one center (see Baker 1993 and references sible that SYs and ASYs show different retention therein). patterns,but morestudy is neededto establish whether or not this is the case. Based on a small Specimen examination revealed that both Black- sampleof MangroveCuckoo specimens it appears billed(Coccyzus erythopthalmus) and Yellow-billed thatmolt patterns and ageing criteria parallel those (C. americanus)cuckoos can retain secondaries in Black-billedCuckoo, at least in northernpopu- and rectricesduring the firstand subsequentmolts. lations. Four of 30 adult Black-billed Cuckoos collected on the breeding grounds (e.g., CAS34955 and Molts in Greater (Geococcyx MVZ127378) had retained2-5 secondariesamong cafifomianus),Smooth-billed Ani (Crotophagaani) sl-s6; two of these had also retained 1-2 rectrices and Groove-billedAni (C. sulcirostris)were found among r2-r3. All four of these birdswere aged SY, to be highly irregular.Flight-feather replacement as determinedby the presenceof pale tips to re- occurredslowly and, generally, very asymmetrically tainedjuvenal secondaries and/or retained juvenal throughoutthe non-breedingseasons. A few rectrices that were narrower,more tapered, and specimensshowed patterns suggesting that both juvenaland adultflight feathers could be retained, Jan.-Mar. North American Bird Bander Page 19 but due to frequentsuspension of molting,adven- Figure 3. Juvenal and adult primary covert (up- titious or irregularfeather replacement,and pro- per) and rectrix(lower) patterns in Greater Road- longed if not year-round breeding, this was diffi- runner. Note also the difference in shape of the cult to confirm. rsctrices. A similar difference in shape can be found in cuckoos,anis and trogons. In the roadrunner,juvenal primary coverts and rec- trices could be distinguished by differences in shape and color patterns(Figure 3), and juvenal secondariesaveraged slightlynarrower, browner, and less glossythan those of adults.These clues allowedconfident separation of HY/SYs fromAHY/ ASYs in most birds throughspring or summer,at whichtime moltingtypically had completedin both age groups.Birds in winter or springwith uniform, Juvenal Adult fresh, adultflight feathers were rare, and were ten- tatively aged AHY/ASY. Some birds (e.g., CAS75518 collectedin April) had one or two very wornfeathers, apparently juvenal, among two gen- erationsof adultfeathers; these were probablyTYs but more study is needed.

In the anis, all juvenal featherswere brownor dull blackishvs. glossy bluishor black in adults, and the rectricesdiffered in shape (see Figure3). As in the roadrunnerthese differencesallowed separa- tion of many HY/SYs and a few AHY/ASYs (with two generationsof adult feathers)through the first summer. Some HYs (e.g., Groove-billed Ani CAPRIMULGIDAE CAS63648) had almost completed the first Molt and its applicationto ageing in the Chuck- prebasic molt in December; thus, birds with uni- will's-widow(Caprimulgus carolinensis) were de- form adult feathers should probably be aged U/ tailedby Rohwer(1971); similarmolt patterns and ßAHY (December-November),if based on ageingcriteria were foundduring this study in most alone. Arrested molt appeared to be rare in anis. NorthAmerican nightjar species. Except as noted below, North American nightjars retain all flight feathersduring the firstprebasic molt, and the adult prebasic molt occurs on the summer grounds. Rohwernoted that the juvenalrectrices in Chuck- will's-widowwere narrowerand more tapered than in adults,and that secondariescould occasionally be retainedduring adult prebasic molts. During this study I confirmedthat both differencesin rectrix shape and retention of secondaries occurred in most NorthAmerican nightjar species, and further foundthat juvenal secondaries and primarycoverts differedin colorpattern from those of adults (Fig- ures 4-5). By combiningthese differenceswith flight-featherretention patterns (especially among the secondaries;Figure 1), many NorthAmerican nightjarscould be aged through SY/TY or ASY/ ATY.

Page 20 North American Bird Bander Vol. 20 No. 1 Molt in Lesser (Chordeilesacutipennis) and Com- mon (C. minor) nighthawks was discussed by Selander (1954). Common Nighthawksdiffer from Lesser Nighthawksand the other North American nightjarsin that most flight-feather replacement occurs on the winter grounds, and that the first prebasicmolt typicallyincludes the rectrices(but notother flight feathers). Selander noted that many nighthawkspecimens retained juvenal secondar- ies, but he assumed that this resulted from an in- completefirst prebasic molt when, according to this study,it resultsfrom an incompletesecond prebasic molt.Of 55 non-molting,spring Lesser Nighthawk specimens examined, 18 (32.7%) had uniform juvenal flight feathers and were aged SY. Eight specimens(14.5%) had uniformadult feathersex- cept 1-4 retainedjuvenal secondaries,usually in a blockamong s2-s6, and were aged TY (Figure 5). Nine nighthawkspecimens (16.4%) had uni- form adult flightfeathers and were aged ASY; and Figure4. Juvenaland adultprimary covert (up- 20 (36.4%) had 1-6 retained adult secondaries per) and secondary(lower) patterns in nightjars. among sl-s8, usually not in a block and often The lightbuff or cinnamontips to the primaryco- asymmetricalin the wings, and were aged ATY verts are diagnosticof juvenalfeathers; however, (see Figures1 and 5). Similarproportions were there can be some overlapin patternbetween found among 60 spring and summer Common juvenal and adult secondaries, which can make Nighthawks,except that a higher percentage of distinctionsbetween SY/TY andASY/ATY (see Fig- birds (38.3%) had uniformadult feathers and the ure 1) difficult.Adults can alsohave pale gray (as numberof retainedfeathers averaged fewer, sug- opposedto buffy)tips to thesecondaries (e.g., see gesting that the molt is more often complete in Figure5). Common than in Lesser Nighthawk.Differences in color pattern between .juvenaland adult sec- ondaries(Figure 5) were greaterin Lesserthan in CommonNighthawk; retained secondaries in some Commonscould not be aged and, like birdswith fully-replacedsecondaries, these individualswere assignedcode ASY.

Molt patterns in the Pauraque (Nyctidromus albicollis), Common Poorwill (Phalaenoptilus nuttallii), Buff-collared Nightjar (Caprimulgus ridgway/)and Whip-poor-will(C. vociferus)paral- leledthose of Chuck-will's-widow,allowing ageing of somebirds to SY/TY or ASY/ATY.The propor- tion of birds with retained secondaries varied Figure5. Secondariesof an SY/TYLesser Night- among these species, from 47.6% of 21 AHY/ASY .Note the retainedjuvenal feathers, that have Chuck-will's-widows examined to 7.1% of 28 AHY/ buffieror morecinnamon tips than adjacent adult ASY poorwillsexamined. As in CommonNight- feathers.Similar patterns of retentioncan be found hawk,distinguishing juvenal from adult secondar- among other nightjars,although differences be- ies can be difficult,and some birds with retained tween juvenal and adult feathers are not as strik- featherscould only be aged AHY/ASY(see Fig- ing in the otherspecies. ure 5). One TY poorwill(CAS26746 collected in Jan.-Mar. North AmericanBird Bander Page 21 May) had retainedthe outertwo juvenal primaries Figure 6. Shape and amount of abrasionin rec- andprimary coverts (Figure 4) in additionto juvenal trices of SY vs. ASY swifts in winter and secondaries(sl-s2 and s7). Retentionof prima- spring.Distinctions are not as apparenton fresher rieswas also notedto occuroccasionally in Com- feathers duringfall. monNighthawks (Selander 1954) and Chuck-will's- widows(Rohwer 1971).

APODIDAE Littlehas been publishedon molt in NorthAmeri- can swifts (see Johnston 1958, Marin and Stiles 1992, Bulland Collins1993). Basedon specimen examination,both first and adult prebasicflight- feathermolts in the BlackSwift ( niger) appear to occur on the winter groundsand are SY ASY complete. In the other three species, Chimney (Chaeturapelagica), Vaux's (C. vauxi),and White- throated (Aeronautessaxatalis) swifts, only the (CAS24721 with pl-p4 being replacedon each adult molt includesthe flightfeathers, this occur- wing) and 4 May in Vaux'sSwift (CAS83744 with ring on the summergrounds. No specimenswere pl-p3 beingreplaced on each wing). The relative foundwith unquestionablyretained flight feathers. timingof flight-feathermolt couldprove usefulfor A few Black Swifts (e.g., CAS45097 and separatingSYs from ASYs through summer, but CAS71832) may have retainedsome secondar- more study based on known-agebirds is needed. ies and greater coverts, but contrastsin feather wear among these specimensmay also have re- TROGONIDAE sultedfrom suspendedmolt or from relativediffer- Based on specimen examination, both Elegant ences in exposure. Little is known of molt in the (Trogonelegans) and Eared(Euptilotus neoxenus) Black Swift or even where North American breed- trogonsretain most to all flight-feathersduring the ers winter(Stiles and Negret 1994). first prebasicmolt. This molt is protractedthrough the first spring, and some but not all HY/SYs of In Blackand White-throatedswifts, juvenal and fe- each species replace the tertials. The adult maleprimaries and rectricesaveraged broader and prebasic molts are complete or nearly complete, blunter than those of adults and males, and this and occur in July to October. Juvenal and adult could be used to help distinguishHY from AHY rectrices are easy to distinguishbased on differ- BlackSwifts in fall (alongwith the scalloped juvenal ences in shape in both species (see Figure3) and bodyplumage; see Drew 1882, Swarth1912), and colorpattern in ElegantTrogons,juvenal outer rec- HY/SY from AHY/ASY White-throated Swifts in trices having narrower bars and juvenal central both fall and spring.The tail fork was also foundto rectriceshaving a narrowerblack tip than are found be deeper in adult males than in juvenileor first- in adults(see Howelland Webb 1995). The color basic males and all females, especially in Black pattern of the secondaries also differs between Swifts.In Chaeturasp., the best way to separate juvenal and adult feathers. In Elegant ,the SY fromASY birdsin winter-springwas by the com- juvenal inner secondaries (s6-s10) have large parativelyabraded tertials, and narrower more ta- white corners that the adult feathers lack. The outer pered and more abraded rectrices(Figure 6) of webs of all secondariesare white, coarsely pep- SYs. pered blackin juvenalfeathers vs. finelyspeckled olive (female) or gray (male)in adult feathers. In SY birds,perhaps non-breeders, also seemed to EaredTrogons the juvenalsecondaries are brown- molt flight-feathersearlier in the spring-summer ish, with littleor no green tinge whereas the adult thanASYs, as early as 12 June in ChimneySwift secondariesare dusky and stronglytinged green.

Page 22 North American Bird Bander Vol. 20 No. 1 Thus, the separationof HY/SY from AHY/ASY mationon replacementof primariesand outer sec- trogonsthrough summer is straightforward. ondariesduring the firstprebasic molt was erro- neouslybased on birdsin secondprebasic molt, A small proportionof trogonscould be aged SY/ as apparentlyoccurred with sapsuckers(see TY or ASY/ATY based on retainedjuvenal or adult Cramp1985, Pyle and Howell in press).Also, re- secondaries,respectively. Of 39AHY/ASYElegant tentionof eitherjuvenal or adultflight feathers was Trogonsexamined only two had retainedsecond- foundduring this examination in mostadult speci- aries;one (MVZ110142 collectedin February)had mens.Of only20 AHY/ASY BeltedKingfishers retainedthe juvenal s5 on the rightwing and was examined(83% of samplespecimens were HY/ aged TY, and another (MVZ110146 collectedin SYs!),six were aged SY/TY, eleven ASY/ATY, and December) had retained the adult s4 and s5 on three had completelyuniform flight feathers or the right wing and was aged ASY. Most of the ambiguousretention patterns and were agedAHY/ eleven Eared Trogons examined had been col- ASY. Juvenal secondaries differed from adult sec- lectedduring active molt, so that retainedsecond- ondaries,on average,in colorpattern (Figure 7) aries would have been difficultor impossibleto and this assistedwith ageingretained feathers. detect.However, one specimen(MVZ139436 col- The blackish center to the central rectrices also lected in July), that was just beginningmolt, had averagedwider in juvenilesand femalesthan in retainedthe juvenal s7 on the rightwing and was adultsand males, although this was only useful in aged TY. The shape of the rectriceson this bird ageingsome HY/SYs as manyapparently had re- was intermediatebetween that of juvenal and adult placedthese feathers during the first fall or winter. feathers(see Figure3), whichmight be typicalin From1-3 juvenalprimaries among p2-p5 were re- SY/TYs. interestingly,higher proportionsof birds tainedin four SY/TYs (e.g., CAS31830collected with retained secondaries were found in other in May),and one late June specimen (CAS17717) trogonspecies, e.g., four of 18 MountainTrogon had begunmolt of the primarieswith p2 and p3, (Trogonmexicanus) specimens at CAS had re- suggestingthat this was a TY that had retained tained one or two feathers. these feathersduring the precedingmolt.

ALCEDINIDAE Figure7. Juvenaland adult secondary patterns in Molt in the Belted Kingfisher(Ceryle alcyon)was BeltedKingfisher; the figure illustrates a typical s6. discussed by Stone (1896), Stresemann and Notethe shapeof the blackshaft streak near the Stresemann (1966), Cramp (1985), and Hamas tip. A similardifference can be foundin Ringed (1994). The firstprebasic molt is extendedthrough- Kingfisher. out the non-breedingseason (Decemberto April) and can include some or all rectrices and appar- ently some outer primaries and secondariesas well, at least in certain eastern migratorypopula- tions.The adultprebasic molt occurs from June to January (most are finishedby November)and in- cludesall or mostflight feathers. Unlike other near- passerines,the primariesmolt distallyand proxi- mally from two centers (often distallyfrom pl and in both directionsfrom p 7), suchthat the last pri- maries replaced are usually among p2-p5. Juvenal Adult

Specimen examinationconfirmed most of this, al- thoughno winter-springSYs in the Californiacol- Molt of the primarycoverts appeared to parallel lections (n=66) were found with symmetricallyre- that in woodpeckers(Pyle and Howell in press), placedprimaries or secondaries(except, perhaps, where the outer 1-4 feathers (and probablysome the tertialsin a few specimens).This contrastin innermostones) are replacedduring the second moltextent with easternpopulations is interesting prebasic molt, and an irregular number are re- and should be confirmed;it is possiblethat infor- placedduring subsequent molts. Atypically, these Jan.-Mar. North Ameri• Bird Bander Page 23 feathersdo not appearto be replacedwith corre- place 'individualsof many North American near- spondingprimaries. If consistentin Belted King- passerinesin older age categoriesthan are cur- fisherthis wouldprovide the best clue to ageing, rentlybeing assigned.In many speciesthe reten- withSY/TYs having1-4 consecutive,outer primary tion of juvenal or adult flight feathers, especially covertsblack and fresh, contrastingwith consecu- among the secondaries,can be used to age birds tive innerprimary coverts brown and abraded (see through SY/TY or ASY/ATY. Reliable ageing of Pyle and Howellin press).Several specimens had near-passerines,however, requires caution and/ thispattern (e.g., CAS31830 mentionedabove and or experiencein many cases. In many birds, molt MVZ23674 collectedin June), and, alongwith re- patternsmay not be easily distinguishedwithout tained juvenal secondaries,were aged TY. More practice, or may conflictwith what would be ex- studyis needed on retentionpatterns of flightfeath- pected given the above information.Responsible ers in Belted Kingfisher,based on a largerseries ageing alwaysincludes the willingnessto place a of AHY/ASY birds. Examinationof twelve Ringed birdin a less-preciseage groupshould any uncer- Kingfisher(C. torquata)specimens suggests that taintyexist. While it is expectedthat the above cri- the same molt patternsand ageing criteriaapply teriawillassist in the moreaccurate ageing of near- in this species, possiblywith more feathers re- passerinesin North America, confirmationand/or tained, on average. further informationis needed based on study of known-agecaptive or marked individuals. Flight-feather molt in Green Kingfisher (Chloroceryle americana) differed from that of ACKNOWLEDGMENTS Belted Kingfisherin that up to six outer primaries and 3-5 secondaries(among s6-s13) are replaced I thankKaren Cebra and LuisBaptista of CAS and during an extended first prebasic molt, and that Ned Johnson and Carla Cicero of MVZ for assis- subsequentprebasic molts appeared most often tance and permissionto examine specimens un- to be complete.Thus, HY/SYs couldbe separated der their care, and Steve N.G. Howell for prepar- fromAHY/ASYs duringwinter and springby con- ing the illustrationsand for reviewingthe text. Mar- trastingnew and old primariesand secondaries.A tin Schaefer assisted me with examination of few AHY/ASY birds may have had one or two re- trogons at MVZ. Comments by ChristopherW. tained primaries and secondaries (e.g., Thompson,Charles C. Collins,and RobertC. Tweit MVZ82240, collectedin Texas in January,with p5 substantiallyimproved the manuscript.This is con- andsll -s12 on eachwing retained and apparently tribution # 660 of PRBO. ßhaving completed molting),but juvenal and adult secondarieswere difficultto distinguishand such LITERATURE CITED birds were aged AHWASY. The primary coverts typicallyappeared to be retainedcompletely in HY/ AmericanOrnithologist's Union. 1983. Check-list SYs, being uniformlygreenish-brown when worn, of North American birds. 6th edition. Amer. and completelymolted in most AHY/ASYs, being Ornithol.Union, Washington, DC. uniformlydark glossygreen, Some AHY/ASY Baker, K. 1993. Identificationguide to European specimens may have had mixed generations of non-passerines.Field guide # 24, British primarycoverts but, again, separationof SY/'rY Trustfor ,Norfolk, U.K. from ASY/ATY based on retention patterns ap- Bent, A.C. 1932. Life histories of North American peared to be difficultat best. Possibleextended or gallinaceousbirds. U.S. Nat. Mus. Bull. year-roundbreeding, especially in tropicalAmeri- 162. Washington,DC. can populations,may complicatemolt patterns and ß 1938. Life histories of North Ameri- ageing in this species. can birds of prey. Part 2. U.S. Nat. Mus. Bull. 170. Washington,DC. CONCLUSIONS ß 1939. Life histories of North Ameri- can woodpeckersU.S. Nat. Mus. Bull. Knowledgeof flight-featherretention patterns and 174. Washington,DC. tin'ling,along with differencesbetween juvenal and adult flight feathers, can be used to confidently

Page 24 North American Bird Bander Vol. 20 No. 1 ß 1940. Life histories of North Ameri- Johnston,D.W. 1958. Sex and age charactersand can cuckoos,goatsuckers, hummingbirds, salivaryglands of theChimney Swift. Con- and theirallies. Two parts.U.S. Nat. Mus. dor 60:73-84. Bull. 176. Washington,DC. Johnston,R.F. 1962. Precocioussexual compe- Bull, E.L. and C.T. Collins. 1993. Vaux's Swift. In tence in the Ground Dove. Auk79:269-270. The Birds of North America, No. 77 Marin,A.M. and F.G. Stiles. 1992. On the biology (A.Pooleand F. Gill, Eds.).Acad. Nat. Sci- of five speciesof swifts(Apodidae, ences,Philadelphia;Amer. Ornithol. Union, )in CostaRica. Proc. West. Washington,DC. Found. Vert. Zool. 4:287-351. Canadian Wildlife Service and U.S. Fish and Wild- Mueller,A.J. 1992. Inca Dove./nThe Birdsof North life Service. 1991. North American Bird America,No. 28. (A. Poole and F. Gill, BandingßVols. 1 and 2. Environment eds.).Acad. Nat. Sciences,Philadelphia; , Can. Wildl. Serv., Ottawa, Canada Amer. Ornithol.Union, Washington DC. and U.S. Fish and Wildl. Serv., Washing- NationalGeographic Society. 1987. FieldGuide ton DC. to the Birds of North America. Nat. Cramp, S., ed. 1985. Birdsof the westernPale- Geo. Soc., WashingtonDC. arctic. Vol. 4. Oxford Univ. Press, Oxford, Nolan, V. Jr. 1975. Externaldifferences between U.K. newlyhatched cuckoos (Coccyzus Drew, F.M. 1882. Notes on the plumage of americanusand C. erythopthalmus).Con- Nephoectesniger borealis.Bull Nuffalt dor 77:341. Ornith. Club 7:182-183. Norman,S.C. 1991. Suspendedsplit-moult sys- Evans, D.L. and R.N. Rosenfield.1987. Remigial tems- an alternativeexplanation for some molt in fall migrant Long-earedand North speciesof Palearcticmigrants. Ring. & ern Saw-whet owls. Pp. 209-214 in R.W. Migr. 12:125-138. Nero, R.J. Clark, R.J. Knapton,and R.H. Oberholser,H.C. 1974. The bird life of Texas. Vol Hamre, eds, Biologyand conservationof 1. Univ. Texas Press, Austin. northern forest owls. U.S. For. Serv. Gert. Pyle,P. and S.N.G. Howell.In press. Flight-feather Tech. Rap. RM-142. molt patternsand age in NorthAmerican Forbush, E.H. 1927. Birds of Massachusetts and woodpeckers.J. Field OrnithoL otherNew Englandstatesß Vol. II. Common Roberts, T.S. 1955. A manual for the identification wealth of Massachusetts, Bostonß of the birds of Minnesotaand neighboring Forsman,E.D. 1981. Moltof the SpottedOwl. Auk states.Univ. Minn. Press, Minneapolis. 98:735-742. Rohwer,S.A. 1971. Molt and the annual cycle of Ginn, H.B. and D.S. Melville. 1983. Moult in birds. the Chuck-will's-widow(Caprimulgus Guide# 19, BritishTrust for Ornithology, carolinensis).Auk 88:485-519. Tring, U.K. Rohwer,S.A. and J. Manning. 1990. Differences Hamas, M.J. 1994. BeltedKingfisher. In The Birds in timingand numberof moltsfor Baltimore of NorthAmerica, No. 84 (A. Poole,and F. and Bullock'sorioles: implications to hybrid Gill, eds.). Acad. Nat. Sciences,Philadel- fitnessand theories of delayed plumage phia;'Amer.Ornithol. Union; Washington maturation. Condor 92:125-140. DC. Selander,R.K. 1954. A systematicreview of the Howell,S.N.G. and S. Webb. 1995.A guideto the boomingnighthawks of western North birds of Mexico and northern Central America. Condor 56:57-82. America.Oxford University Press, Oxford, Stiles, F.G. and A.J. Negret. 1994. The U.K. nonbreedingdistribution of the Black Swift: Humphrey,P.S. and K.C. Parkes.1959. An ap- A clue from Columbiaand unsolvedprob- proachto the studyof moltsand . lems. Condor 96:1091-1094. Auk 76:1-31. Stresemann, E. and V. Stresemann. 1966. Die Jenni, L. and R. Winkler.1994. Moult and aging in mauserder Vogel. J. Ornithol.107:1-447. Europeanpasserines. Academic Press, Swarth, H.S. 1912. Differences due to sex in the New York. Black Swift. Auk 29:241-242.

Jan.-Mar. North American Bird Bander Page 25 Thompson,C.W. and M. Leu. 1994. Determining Tweit, R.C. 1986. Inca Dove. Western Bird Band- homologyof moltsand plumagesto ad- ing AssociationWorksheet. dress evolutionaryquestions: a rejoinder Wood, M. 1969. A bird-bander'sguide to the de- regardingemberizid . Condor terminationof age and sex of selectedspe- 96:769-782. cies. Coil.Agric., Pennsylvania State Univ., Test, F.H. 1945. Molt in flightfeathers of flickers. UniversityPark. Condor 47:63-72. News, Notes, Comments Live Recovery of a Venerable Raptor A Longevity Record for the Red-tailed Hawk On 12 November 1994, a banded Red-tailed Hawk tors includedin the list, only the followingfour were (Buteojamaicensis), USFWS #877-17127, was cap- shownto havesurvived 20 yearsor longerin the wild: turedat the KittatinnyMountains Raptor Banding Sta- tion, SussexCounty, New Jersey,by Chris Lanna. BlackVulture (Coragyps atratus) ...... Thisbird had been banded by Chet Robertsonas an 25 years,6 months AHY, near Kempton,Pennsylvania, on 21 October Osprey(Pandion haliaetus) ...... 1972. Usingthe Bird BandingLaboratory's (BBL) 23 years, 0 months assumedhatching date of I June (Clapp,R.B.; M.K. Red-tailedHawk (Buteojamaicensis) ..... Klimkiewicz;and J.H. Kennard. 1982. Longevity 22 years, 7 months recordsof North AmericanBirds: Gaviidae through Bald (Haliaeetusleucocephalus) . . . Alcidae.J. Field Ornithol.53:81-124), this bird had 21 years, 11 months liveda minimumof 23 years,5 months--alongevity recordfor the species. Lannareported the birdwas Thus,the 23 year,5 monthold bird described here is ingood condition, was alert and strong, and appeared the oldest Red-tailed Hawk and the second oldest di- to be healthyin everyway. urnalNorth American raptor known--a venerable bird, indeed. I thinkit's noteworthy that the USFWS lock-onband, whichalso had endured for over 22 years,was stillin I thankKathy Klimkiewicz of the BBLfor providingme good condition. Althoughthe lock-onflange was withbanding recovery data and for reviewingthis pa- slightlyloose and needed tightening,the band was per. legibleand showedonly minimal wear. The birdwas Leonard J. Soucy, Jr. photographedand released. 1390 White BridgeRoad Millington,NJ 07946 BBLrecords indicate that as of 31 August1994, there have been 101,548 Red-tailed banded, and 5,194(5.1%) have been recovered. The recoverydata clearlyshows that although these raptors are capable of livinglong lives, very few actuallydo. Of the 5,194 recoveredbirds, only 31 survived17 yearsor more, andjust 11 survived20 yearsor more. The longevity recordfor the Red-tailedHawk (2 individuals)was 22 years,7 months(Klimkiewicz, M.K. and A.G. Futcher. 1989. Longevityrecords of North American birds: supplement1. J. Field Ornithol.60:469-494.). The birddescribed here surpasses that recordby nearly one full year.

Clapp, et al. (1982) and Klimkiewiczand Futcher (1989)provided a listof longevityrecords of North Americanbirds. Of the 24 speciesof diurnalrap- Page 26 North American Bird Bander Vol. 20 No. I