88
Wader Study Group Bulletin
ously.Kozlova (1962) claimedsimultaneous
moult usually
for the first threeor four primaries,but sometimesthe first
five or six.Sucha rapidstartof primarymoulthasneverbeen
recordedin migratingDunlinscaughtin the first stagesof
moult at the Vistula mouthin Poland(J. Gromadzkapers.
includedProfessorEvgeniySyroechkovsky
andhis staffat
theInstituteof EvolutionaryAnimalMorphologyandEcology, USSR Academy of Sciences, and Director Juriy
Karbainov,Warden Victor Khristophorofand staff of the
"Taymyrskiy"Nature Reserve.
comm.).
The moultprogressed
very quicklyin the Dunlinsin the
Taymyr which were studiedin 1989. It is not knownif moult
was suspendedafter the end of incubation.If moult continues at a similarrate in the secondpart of the moult period,
theprimarymoultwouldtakec.50 days.This is a markedly
shorterperiod than the 59-94 daysreportedfor primary
moult in post-breedingDunlins(Ginn & Melville 1983).
References
Ashmole,N.P. 1962. The Black Noddy Anoustenuirostrison the AscensionIsland.Part I. GeneralBiology.Ibis 103: 235-273.
Danilov, N.N., Ryzhanovskij,V.N. & Ryabitsev,V.K. 1984. Birds of
Yamal. Nauka, Moskva. [in Russian]
Ginn, H.B. & Melville, D.S. 1983. Moult in birds. BTO Guide 19. BTO,
Tring.
Greenwood,J.G. 1983. Post-nuptialprimary moult in Dunlin Calidris
Acknowledgements
alpina. Ibis 125: 221-228.
Gromadzka,J. 1989.Breedingandwinteringareasof Dunlin migrating
throughsouthernBaltic. Ornis Scand.20: 132-144.
Kozlova,E.V. 1962. Fauna SSSR.Birds.Vol. 2, subvol1, part 3. Nauka,
Moskva, Leningrad.[in Russian]
Soikkeli,M. 1966.On thevariationin bill- andwing-lengthof theDunlin
(Calidris alpina) in Europe.Bird Study13: 256-269.
Soikkeli,M. 1967.Breedingcycleandpopulationdynamicsin theDunhn
JadwigaGromadzka,PrzemyslawChylarecki,Nick DavidsonandHermannH6tker gavevaluablecommentson earlier
draftsof this paper.Membersof the WWF expeditionfrom
HQsum(FRG) - PeterProkosch,
HolgerA. Bruns,H. H6tker,
Willi Knief, JohanMooij - andmembersof the expedition
(Calidris alpina). Ann. Zool. Fenn. 4: 158-198.
of the Black/Azov SeasOrnithologicalStation(Ukraine),
Tomkovich, P.S. 1988. On the originality of breeding biology of
Valerij Siokhin, Igor Belashkovand Tatiana Kirikova Temminck's Stint Calidris temminckii at the northern limit of its area
participatedin the collectionof data. I am grateful to all
Ornitologiya 23: 188-193.
individuals and organisationswho made our researchin Underhill,L.G. & Zucchini,W. 1988.A modelfor avianprimarymoult.
Taymyr possible and gave us logistic support. These
Ibis 130: 358-372.
Relative masses of primary feathers in waders
L.G. UNDERHILL • & R.W. SUMMERS 2
1ArianDemography
Unit,Department
of Statistical
Sciences,University
of CapeTown,Rondebosch
7701,
South Africa
2Lismore,Mill Crescent,NorthKessock,Inverness,IV1 1XY, Scotland,UK
Citation: Underhill, L.G. & Summers, R.W. 1993. Relative masses of primary feathers in waders.
Wader Study Group Bull. 71: 29-31.
Summerset al. (1983) showedthatmoultscoresof retrapped
RedshanksTringa totanustendedto increasemore slowly
towardsthe end of primarymountthannearthebeginning.
This waspartlybecausethe outerprimariesare longerand
heavierthan the innerprimaries.Therefore,by converting
moult scoresto percentage
feathermassgrown(PFMG) one
canmakethepatternof increasewith time morelinear(Summers1980).A "moultindex"thatincreases
linearlywithtime
is one of the underpinningassumptions
of the moult model
of Underhill& Zucchini(1988), andPFMG is undoubtedly
morecloselylinearwith timethanthetraditionalmoultscore.
In orderto computePFMG, the relativemassesof the primary feathersfor the speciesunderconsideration
needto be
known.
One of the purposesof thisnoteis to point out that, for
thosewaderspeciesfor whichtherelativemassesof theprimariesareknown,thereis sufficientlylittle variationto sug-
gestthat a setof averagevaluesmight sufficefor all (or at
leastmost)wader species.The otherpurposeof this noteis
to suggesta standardprocedurefor determiningtherelative
massesandfor computingPFMG. Improvedstandardisation
of methodswill facilitatecomparisons
betweenspeciesand
betweenareasin the timing anddurationof moult.
To date, the relative massesof the primarieshave been
determinedfor 13 waderspecies(Table 1). For thesespecies
and each primary, the maximum difference between the
averagerelativemassesandtherelativemassesfor the individualspecieswas 1.3%. The consistent
differenceswerefor
Grey Plover PluvialIs squatarola,which appearsto have
relatively lighter inner and heavier outer primaries than
average,andRedshankfor whichtheoppositepatternoccurs
(Table 1).
The recommendedprocedurefor finding relative masses
was describedby Summerset al. (1980), and is repeated
• Bulletin
69
Special
Issue
July
1993
89
Morphometrics: moult
Table 1. Relative masses of primarywing feathers of waders.
Source
Primary number
Species
Grey Plover Charadrius squatarola
Bar-tailed Godwit Limosa lapponica
Whimbrel Numeniusphaeopus
Bristle-thighedCurlew N. tahitiensis
RedshankTringa totanus
I
2
3
4
5
6
7
8
9
10
3.1
4.1
3.8
4.0
5.0
4.0
4.9
5.0
5.0
5.7
5.1
6.0
6.3
6.1
6.7
6.8
7.7
7.5
7.6
7.7
8.4
9.4
8.8
9.2
9.1
10.5
11.0
10.7
10.9
10.6
12.7
12.1
12.2
12.2
11.8
14.6
13.5
13.9
13.5
13.1
16.3
14.8
15.3
15.1
14.2
18.5
16.6
16.5
16.4
16.1
Greenshank T. nebularia
4.4
5.1
6.0
7.3
8.8
10.4
12.1
13.7
15.3
16.9
TurnstoneArenaria interpres
Knot Calidris canutus
SanderlingC. alba
4.2
3.9
3.9
4.7
4.5
4.6
5.9
5.5
5.4
7.2
7.1
6.8
8.7
8.6
8.3
10.4
10.6
10.2
12.0
12.3
12.0
13.7
14.0
14.2
15.4
15.7
16.0
17.9
17.8
18.7
Little Stint C. minuta
4.4
5.2
6.1
7.3
8.6
10.3
12.0
13.7
15.4
17.1
Purple SandpiperC.Maritima
Dunlin C. alpina
Curlew SandpiperC. ferruginea
4.4
4.0
4.0
5.0
4.9
4.7
6.0
5.7
6.0
7.0
6.9
7.3
8.6
8.5
8.8
10.2
10.2
10.3
11.6
11.8
12.2
13.2
13.7
13.9
15.5
15.8
15.3
18.5
18.4
17.6
Average
mi
4.1
4.9
5.9
7.3
8.8
10.5
12.0
13.7
15.4
17.4
(a)
(b)
(c)
(d)
(e)
(f)
Sources:(a) Marks in prep.; (b) Summerset al. 1983; (c)Summers et al. 1989; (d) WCWSG unpubl. data; (e) Underhill & Zucchini 1988;
(f) Kania 1990, in litt.
here,with somerefinements.Primaryfeathersin goodcondition (i.e. showinglittle featherwear and with no brokenoff tips) areneeded.The basesof thefeathersmustbe clean
andundamaged.If they meet the criteria,the feathersfrom
bothwingsshouldbe used.The feathersare labelled,dried
to constantmassin a convectionoven(24-48 hoursat 60øC),
andthenweighedasrapidly as possible.For waders,1 mg
accuracyis adequate.The feathersstartreabsorbing
moisture
as soon as they cool off; this can be checked for by reweighingthe first few feathersafterthelastfeatherhasbeen
weighed.
To determinethe relative massesof eachprimary for a
singlebird, addtogetherthe massesof corresponding
pairs
of primaries(assuming
bothwingswereused),anddivideby
the total massof all 20 primariesfor that bird. If data from
severalbirds are available, the means (and standarddeviations)of therelativemassesof eachprimaryfor eachbird are
computed.Other orderingsof the stepsin doingthe calculationsarepossible,andmostwill leadto identicalor nearly
identicalresults.The key pointis thatthesamplesizeshould
be the numberof birds,not thenumberof wings.From previous experience,the standarddeviationsshouldbe small,
andthe coefficientsof variationcanbe expectedto be less
Table 2. Recommended factors for converting moult scores for
individualfeathers to proportionof feather mass grown. The motivation for these values is given in Underhill & Zucchini (1988).
Score s
Proportion grown p(s)
0
0
1
0.125
2
0.375
3
0.625
4
0.875
5
1
pleted23/50 = 46% of itsprimarymoult).If thewaderhadbeen
a Grey Plover Pluvialis squatarola,and the 'correct' relative
massesfor this specieshadbeenusedinsteadof the average
values, the PFMG would have been calculatedat 24.7%, and,
if a Redshank,as 31.1%. Thesediscrepancies
representvirtually the worst casedeviationsamongstthe 13 speciesconsidered, but will not introduce seriousbiasesin the estimatesof the
moultparameters
by themethodof Underhill& Zucchini(1988).
Of the 13 specieslistedin Table 1, 12 representfive of the
than about 2%.
generawithin the Scolopacidae,but all are migrants.Only
To transformthe primary moult scorefor a wader with
one plover Charadriidaeis includedin Table 1. Therefore,
moultrecordedaccordingto the systemof Ginn & Melville
the current and provisional guideline is that for migrant
(1983)ass1S2S3S4S5S6S7S8S9S
10(e.g.5554310000)
intoPFMG, scolopacidsand possiblycharadriids,the averagerelative
the formula of Underhill & Zucchini (1988) is recomprimary massesfrom Table 1 may be used to compute
mended:
PFMG. Furtherinformationis requiredfor otherwaderfami10
lies, but alsofor "resident"scolopacids,suchasthe African
PFMG= Y;mi P(Si)
SnipeGaiinagonigripennis,for scolopacids
from generanot
i=1
represented
in Table 1, andfor charadriids,
bothmigrantand
wheremi istherelativemassof theithprimary,
andP($i) isthe resident.We would be grateful to receive air-dried fresh
mass
of a feather
withamoultscore
si relativetoitsmasswhen wings from any wader (includingthosein Table 1), with a
it isfullygrown.Thevaluesformi maybetakenfromTable1, sampleof no more thanfive pairsof wings.Thus, in future,
andthoseforp(si ) (assumed
to bethesamefor eachprimary) we wouldbe ableto updateourknowledgeof relativemasses
from Table 2. The examplein Table 3 showsthat a primary of primaries.
moult scoreof 5554310000 transformsto a PFMG of 28.1%, inRelativeprimarymassesfor five non-wadersaregivenin
dicatingthatthebirdhasgrown28%of theprimaryfeathermass Underhill et al. (1991, Table 17), and all are different from
(whereasthe traditionalmoultscoreformedby summingthe eachotherandfrom the valuesgivenfor wadersin Table 1,
scoresfor theindividualfeatherssuggests
thatthebirdhascorn- which should therefore not be used for other families.
Bulletin69 Special Issue July 1993
9O
Wader Study Group Bulletin
Table 3, Workedexampleof the procedurefor transforming
a moultscorerecordedas 5554310000
to PFMG.
Primaryi
Relativemass
m(i)
Score s/
Proportiongrown
p(s/)
m/x p(s/)
1
4.1
5
1
4.1
2
4.9
5
1
4.9
3
5.9
5
1
5.9
4
7.3
4
0.875
6.4
5
8.8
3
0.625
5.5
6
10.5
1
0.125
1.3
7
12.0
0
0
0.0
0.0
8
13.7
0
0
9
15.4
0
0
0.0
10
17.4
0
0
0.0
10
PFMG= Z miP(Si)= 28.1%
i=1
Acknowledgements
Marks, J.S. 1993. Molt of Bristle-thighedcurlews in the Northwestern
LGU acknowledgessupportfrom the University of Cape
Summers,R.W. 1980. On the rate of changeof moult scoresin waders.
Wader StudyGroup Bulk 28: 24.
Hawaiian
Town
Research
Committee
and from the Foundation
for
Islands. Auk 100: 573-587.
Summers, R.W., Swann, R.L. & Nicoll, M. 1983. The effects of methods
ResearchDevelopment,Pretoria.Unpublisheddatawasproon estimatesof primary moult duration in the RedshankTringa
videdby theWesternCapeWaderStudyGroup(WCWSG)
totanus.Bird Study 30: 149-156.
andJ.S.Marks,who,alongwith R.P. Prys-Jones,
commented Summers,R.W., Underhill, L.G., Clinning, C.F. & Nicoll, M. 1989.
on an earlier draft.
Populations,biometricsand moult of the TurnstoneArenaria interpres,with specialreferenceto the Siberianpopulation.
Ardea77: 145168.
References
Underhill,L.G. & Zucchini,W. 1988. A modelfor avianprimarymoult.
Ginn, H.B. & Melville, D.S. 1983. Moult in birds.BTO Guide 19. Tring:
British Trust for Ornithology.
Kania, W. 1990. The primarymoult of breedingDunlinsCalidris alpine
in the centralTaimyr in 1989. WaderStudyGroupBull. 60: 17-19.
Underhill, L.G., Oatley, T.B. & Harrison,J.A. 1991. The role of largescaledata collectionprojectsin the studyof southernAfrican birds.
Ibis 130: 358-372.
Bulletin 69 Special Issue July 1993
Ostrich 62: 124-148.