Towards a flyway conservation strategy for waders
N.C. Davidson, P.I. Rothwell & M.W. Pienkowski
Davidson,N.C., Rothwell,P.I. & Pienkowski,M.W. 1995. Towardsa flyway conservation
strategyfor waders. Wader Study GroupBull.77: 70-81.
Waterfowl migratoryflywaysare one of the world'sbiologicalwonders. Their maintenanceand
enhancement should be a global conservationpriority. There have been, and are, a great
variety of local, nationaland internationalconservationinitiativesand actionsthat contribute
towards conservingmigratorywaterfowl. Many vital places on wader flyways continue,
however,to be degradedand destroyeddirectlyor indirectlyby human activities. To put in
place a unifyingflywayconservationprogrammea numberof key preliminarystepsare needed
These includeidentifyingand filling gaps in knowledgeof how waders use the flyways;
identifyingwhen and where human activitieshave an adverse impact; quantifyingsuch impacts
and filling gaps in knowledge;and identifyingthe current level and efficacy of conservation
action along flyways. Based on existinginformation,the paper describesexamples of flyway
researchand conservationand identifiesknowngaps in knowledge. Examplesare drawn
largely from the East Arianticflyway but most are just as relevantto wader flywaysworldwide.
Suggestionsfor taking forwardsa co-ordinatedprogrammefor wader flyway conservationare
made.
N.C. Davidson & M.W. Pienkowsk?, UK Joint Nature Conservation Committee, Monkstone
House, City Road, PeterboroughPE1 1JY, UK. (*present address:Royal Societyfor the
Protectionof Birds, The Lodge, Sandy, Beds. SG19 2DL, UK)•
P./. Rothwel/,Royal Societyfor the Protectionof Birds, The Lodge, Sandy, Beds. SG19 2DL,
UK.
INTRODUCTION
There is considerable
worldwide
These coastal wetlands in western Europe of course form
just one part of the links in the chain that makes up the
East Atlanticflywayjigsaw. There are similar flyways
around and throughmost other parts of the world (see
Davidson& Pienkowski1987), and similar suitesof
coastal and inland weftands, and drier habitats in urgent
need of safeguard.
interest in the field of
waterfowl biology. Our knowledge of such aspects of a
bird'slife cycle as reproductivebiology,moultingand
migratorystrategiesincreaseswith each year. In our
pursuit of scientificideal we should not, however, lose
sightof the fact that bird migratoryflywaysare one of the
biologicalwondersof the world. They are a living
reminderthat we all inhabitone planet and that what may
seem to be local actionscan have consequencesfor the
environmentsof other biotopesand in other hemispheres.
Althoughmuch conservationeffort is expendedat local
and national levels, for conservationists to be successful
in the objective of maintaining and enhancingthe bird
populationsthat use flywaysa more holisticvision is
required. It is the nature of virtuallyall major flywaysto
cross many countriesand for birds to utilise different
habitats at differenttimes of year. Such habits make
standardapproachesto researchand conservation
difficult. Conservationlaw and its implementationis
applied unevenlyand levelsof research interestpatchy.
Effectiveflyway understandingand conservationcan be
achieved only by an integratedapproach along the whole
flyway, and perhapsalso betweenflyways. Such an
approach requiresconsiderablecommitment and co-
Migrantwaders make some of the most spectacularof
these migrations,oftentravelling non-stopin flightsof
several thousand
kilometres.
Our interest in the detail of
their annual cycles in relationto migrationsis thus both
justified and, in world conservationterms, one of our
highestpriorities.
Whilst taking great satisfactionfrom our commonand
necessaryinterestin the detail of what makes up the
flywaythere is a gravedangerthat we lose sightof the
whole picture. in the UK and mainlandwesternEurope
much work has been done to promotethe conservationof
estuariesand coastal wetlands,the winteringgroundsof
so many of the same East Atlanticflyway bird populations
as breed in eastern Europe and northernAsia. Indeed
these migratorybird populationsand their use of
internationalnetworksof siteshave oftenbeena major
element in the development of conservationmeasures for
wetlandecosystemsand their wildlife.
ordination, but is essential.
It is no longersufficientto considerthe links in the flyway
chainin isolation. Researchin basic biology,the extent
and impact of threats, and the conservation,protection
and enhancementof speciesand habitatsare all essential
to the maintenanceof the flyway.
in this short paper we seek to identifythe needsto make
whole flyway conservationa reality, and to move towards
a structureco-ordinatingour activities in the future that
will deliverthe ultimateaim - the safety, maintenanceand
70
rogersi'
islan,
I
breeding
area
•
stagingarea
IIIIIIIIIIIII
wintering
area
....::• staging
andwintering
area
:*i,.,•'*
•[•;•
migratory
corridors
Figure1. Evenforwell-researched
waderswithsimplemigration
systemspartsofthe worldwide
flywaynetworkare poorlyestablished:a recent
reviewofthe currentknowledge
of the migration
systemof the KnotCalidriscanutus(Davidson
& Piersma1992)showsthatmanyuncertainties
aboutmigrationroutesremain.
enhancementof migratory bird populationsand the
habitatsuponwhich they dependthroughoutthe world.
Althoughwe will draw examples of the needs and
processesof wader flyway conservationlargely from the
East Atlantic flyway, the approach is largely applicable
also to other flyways worldwide.
INFORMATION
a What pressuresthreaten continuedusage of each
site?
b. What are currentconstraintson site use by waders?
c. How can be, and are, sites modified, and what are the
consequencesof these modifications?
d. How can this knowledgebe best usedto developand
implementflyway conservationprogrammes?
NEEDS
Conservation
actions
To put in place effectiveflyway conservationaction, we
need severaltypes of informationabout the flyways and
the way in which wader speciesand assemblages use
them. To provide this informationwe need the answers to
several questionsthat can be groupedinto three broad
categories,summarised as:
a. What level of conservationlaw provisionexistsin
differentcountriesalong a flyway?
b.
How can this conservation
Basic biology
c.
How does site-based
law be used to deliver
nationalactions and internationalco-operation?
conservation
fit into the broader
needs of dispersed species?
a.
Where
are the sites used?
d. How can the flyway conservationneedsof waders be
linkedwiththe sustainableuse and developmentof
b. What is the ecology and populationdynamics of the
wader species?
their habitats?
c. What role does each site play in the annual cycles of
each species?
e. How can conservationprovisionfor wader flywaysbe
enhanced, especiallywhere weak?
d. How is each site related to the usage of other sites in
the flyway?
Althoughsome of these questionsare deceptivelysimple,
as we describebelowthey can be very complexto
answer. Neverthelessto provideclear and strong
argumentsfor conservationactionto safeguardwaders'
needs,increasinglydetailedunderstanding
of how and
why nationallyand internationallyimportantpopulations
e. What features of each site determine how it is used?
Threats and opportunities
7!
of waders use their flyways, and what pressuresand
impacts affect this usage.
Much action is directed towards
individual
flyways. This is particularlyso when consideringthe
detail of migrationroutes,the interdependenceof
winteringsites, and the breedingbiologyand distribution
of many species. Further reviewsof flywaysand reserve
networksfor various groups of waterbirdsappear in Boyd
& Pirot (1989) and Salath6 (1991 a).
sites on a
flyway - it is often informationon the links betweensites
(and flyways)that is most difficultto gatherand so least
known. Furthermore it is important also to consider
individualsites of identifiedhigh importancefor migratory
wader populationswithin the wider matrix of the relevant
ecosystems,since some wader populationsare
widespreadaroundthe resource(see e.g. Davidsonet al.
1991; Davidson & Stroud 1995).
There has perhapsbeen more extensiveand detailed
investigationof the East Atlanticflywaythan for any other
wader flyway, and there have been furtherdiscoveries
and reviewof wader usage of this flyway (e.g. Smit &
Pierstoa 1989) since the reviews in Davidson &
Pienkowski(1987), but startlinglylarge gaps remain even
Conservationprogrammes,at both nationaland
internationallevels, are generallydirectedtowardsthe
safeguardingof individualsites, sometimeswithina
broaderframework of sympatheticland-useaction.
Conservationof flyway populationsof waders can be, and
often is, approachedthroughthe generalsafeguardof
sites used by the flyway wader assemblage. However,
since each wader species has a differentset of
requirements,and uses a differentsuite of sites, it is also
essentialto understandflyway usage by individual
species and populations. This poses challengesfor
assessing how and whether sustainabledevelopmentof
wetland habitats can be consistentwith flyway wader
here•
Internationalassessmentshave been generallyrestricted
to singleflywaysand broad patternsof usage by
individualspeciesor populationswithin a flyway. Yet to
set conservationprioritiesin contextand to stimulate
conservationaction more comprehensivelywe need also
to understandworldwideflyway occurrenceand use by
the relevant species. Few such assessments have been
made in detail (but see Hunter et al. 1991; Lane & Parish
1991; Gill et al. 1994).
As a follow-upto the broad assessment of flyway
conservationfor waders (Davidson & Pienkowski1987),
the Wader Study Group has more recentlypublisheda
worldwidereview of the migrationsystemsof one wader
species,the Knot Calidriscanutus(Pierstoa & Davidson
1992), a specieschosen because it is generally
consideredto have a simple migrationsystem(Figure 1)
and to be amongstthe best known migrantwaders.
Certainlythe Knot has been the target of a great deal of
interestand research over the last 20 years. This review
has permitteda comparativeassessmentof key
characteristicsin each subspeciesand also allows an
appraisalof the extentto which our currentknowledge
can contributeto the developmentof flyway conservation
action (Table 1).
conservation.
THE
BASIC
BIOLOGY
To achieve a successfulprogramme of conservationand
managementof any biologicalsystem,speciesor habitat,
a depth of knowledgeof the mechanicsof the system is a
prerequisite. In 1987 the Wader Study Group reviewed
the currentstate of our broad knowledgeof wader flyways
(Davidson& Pienkowski1987). This revealedthat
althoughmuch has been discoveredin recentyears about
the distributionand patterns of usage of wader flyways
there remained substantialgaps in knowledgefor all
Table 1. Is knowledgeof the key featuresof flywayuse by KnotsCalid#scanutussufficientfor developingconservationaction?
subspecies
Topic
canutus
islandica
rufa
rogersi
roselaari
Population
size& trend
Breedinglocation
Non-breeding
location
Siteroles& links
¸¸¸
¸¸
Keyfeaturesof sites
¸¸¸
¸¸(•)
Pressureson sites
¸(•)(•)
(•)(•)(•)
•
•
(•)
¸¸
•
(•)
•
•
(•)
Constraints
on site use
Levelof knowledge:¸¸¸
good,¸¸
fair,¸poor, © none.
The resultsare alarming: the only subspeciesfor which
levelsof knowledgeappear broadlyadequatefor
developingconservationaction are the two (canutus and
islandica)usingthe East Atlanticflyway,and evenfor
these there remain uncertainties
about some of the most
basic informationincludingpopulationsizes and trends,
72
and the location of breeding grounds. For other
subspeciesknowledgeis even poorer and for one
(roselaari- probablythe scarcestsubspecies)almost
nothingis known. If gaps of this magnitude exist for a
well-researchedwader speciesthen it followsthat similar
or greater gaps exist in the knowledgeof how other
individualspeciesand populationsuse flyways.
THREATS
There
is a clear need for further review of the
current state of our knowledgeof wader flyways and their
species. In addition such a review should set out to
identifythose gaps in our knowledgeof these flyways and
species. In particularsuch a reviewshouldset out to
identifythose gaps in our knowledgeth,at hold back the
processof flyway conservation.Only followingthis last
step can we then start to set prioritiesfor filling gaps
either through guidance to rather ad hoc continued efforts
or througha co-ordinatedand funded programmeof
research,whicheveris appropriateto the urgencyof need
and availability of resources.
For waders, the Wader Study Group can play an
invaluable role (especiallythrough its r01eas the IWRB
Wader ResearchGroup) in providinga forumfor bringing
together informationfrom wader-workersworldwide and
making it availableto an internationalaudiencethrough
publicationof its Bulletin,BulletinSupplements,and new
publicationseries InternationalWader Studies(IWS).
Special volumes such as those providingfirst estimates of
the size of breedingwader populationsin Europe
(Piersma 1986), summarising international flyway
conservation(Davidson & Pienkowski1987), reviewing
the status of waders breeding on European wet
grasslands(H0tker 1991), and the migration of Knots
(Piersma & Davidson 1992) providefocusedinformation
to answer the basic questionsunderlyingconservation
strategy development.
As the area of suitable
and Wetlands
Research
becomes
recreational
activities.
Rather
little is known in detail
about the effectsand impacts such as disturbanceto
waders but a Wader Study Group BulletinSupplement
(Davidson& Rothwell1993) providesa summaryof the
current limited knowledgeof recreational disturbanceto
waders in north-westEurope.
about the location of sites and wader
Waterfowl
habitat for waders
progressivelyreducedthe many continuinghuman
activitiesare compressedinto smaller and smaller areas.
Furthermore many of these activities are themselves
apparentlyincreasingin scale. This leads to increasing
potential pressure from 'traditional'uses such as shellfisheriesand bait-diggingas well as the wide variety of
populationsin the internationalwader and waterfowl
count programmes and databases co-ordinatedby the
International
- AND
The resultsof such surveywork gives considerable
concernwhen examininga flyway as a whole and
assessing its future. It is the nature of bird migrationto
be so dependenton chainsof suitablesitesthat pressure
pointsor bottle-neckswill occur naturally. The
safeguardingof these places is vital to the maintenance
of the whole system (Lane & Parish 1991).
Likewisethere is a very importantsourceof this key basic
information
SYSTEM
Knowledge of the basic biology of the flyway, their
species and habitats is also essentialto this second
element of our suggested approach. To reach our
ultimate goal of flyway conservation,maintenance and
enhancement,we have to acknowledgeand understand
the pressuresthat are being placedon the system both
naturallyand throughthe activitiesand impact of people.
Recent analyses of patterns of human activityon the
estuarine wintering grounds of waders and wildfowl in
Britain indicate alarming extents of habitat loss and the
frequencyof occurrenceof a wide variety of potentially
damaginghuman activities(Dawdson et aL 1991). Not
only has, for example, at least 25% of Britain's estuarine
habitat been destroyedduringthe last 2,000 years but
such piecemeal land-claimfor a wide variety of human
uses is continuing(despitethe many conservation
designationsappliedto estuaries) at an apparentlylittle
diminished rate. This affects many of the estuaries of
great importancefor migrant and winteringwaders.
This paper seeks not to identifyall such gaps but merely
to identifythe need to address this issue in a co-ordinated
fashion.
TO THE
OPPORTUNITIES
Bureau
(IWRB), the most recentlyestablishedbeingthe
NeotropicalWetlands Census (NWC). In additionthe
various nationaland supranationalcountand population
indexingprogrammessuch as the JNCC/RSPB/BTO
Birds of Estuaries Enquiry in the UK (e.g. Prater 1981;
Kirbyet aL 1992) and (Meltofteet aL 1994) for the
internationalWadden Sea providethe essentialbasis for
developingconservationprogrammes.
Such comprehensivesurvey assessmentsas Davidson et
aL (1991) have been made elsewhere,especiallyin the
USA (e.g. Tiner 1984), but are not yet consistently
available for other major parts of flyways. It is clear,
however,that similarlygreat impacts of human-generated
habitatlossand degradationis widespreadthroughout
many parts of the world (see e.g. Lane 1987; Smith et aL
1987; Bildstein et aL 1991; Biber & Salath• 1991;
Finlayson & Moser 1991; Hunter et aL 1991; Lane &
Parish 1991 ).
We requirea comprehensiveexaminationof the activities
that could potentiallyhave an adverse impact on
migratory bird populationson the flyway. It is essential
that we can assessthe likelyimpact of humans, both
throughtheir existingactivitiesand via the effects of
changesin our use of habitats. Such a programmeof
investigationcouldinvolvealso all-encompassing
problems such as global warming How will this affect
bird distribution?
73
Will areas
10
Landscape/amenity
I Wildlife/nature
cons.
J
•
4
o
CanaryIs.Cyprus
(T) Turkey
Spain Bulgaria
Switzerland
FranceLuxembourg
Belgium
UK
Russia Sweden Iceland Svalbard
Madeira Gibraltar Greece Albania Andorra Hungary Czech* LichtensteinPoland Is.of Man Ireland
Cyprus(Gr) Azores Portugal Italy
Finland Norway
Romania AustriaChannel
Is.Germany*'Netherlands
DenmarkFaroeIs,
Malta Greenland
Country
Figure2. The numberof differenttypesof domesticstatutorywildlifeand landscapeconservation
site designations
in each Europeancountry
(derivedfrom informationin Grimmett& Jones 1989).
and locationsof breedingand winteringhabitatschange,
through for example inundationof tidal flats by rising sealevels and constrictionof Arctic tundra breedingareas
consequenton possiblyaltering Arctic climate? Over
Finally,on a very small scale, how does piecemealsmall
land-claim or recreationor shootingimpact on birds?
Answeringsuch a questioncan requiredetailed research
in each location, but at least in the UK there have as yet
been few impact studiesfor whichthere is adequate
longtime-periodsmajor naturalpopulationdeclinesin
arctic-breedingspecies have been linkedto the periodsof
Pleistocene glaciation, when the area of suitable breeding
habitat would have been severely restricted(Baker et aL
1994), but will additionalhuman pressureartificially
depressthe size of populationsso makingthem less able
to surviveperiodsof naturalstress?
'before and after' data with which to make an assessment
For some countriescollectingsuch site-specific
informationmay not be practicableso we need detailed
studiesundertakenin such a way as to providegeneral
principlesapplicableelsewhere.
It is essentialthat we are able to answer questionssuch
as these if we are to understandhuman impact on the
flyway, and use this understandingto directefforttowards
reducingany impactsfoundto be adverse. As with the
basic biologythere will be clear steps in the process.
There is a need to identifywhat is knownand what is
requiredto be investigated. There is also a need to set
out to fill the gaps in our Knowledgein a co-ordinatedand
plannedfashionto providemaximumbenefitto achieving
conservationand managementgoals. Internationalcooperationmeans that not everyonehas to 'inventthe
same wheel': generalstudiesmade in one countrycan be
applicablealso to others. This resultsin the cost-effective
On a smaller scale we should be quite clear as to the
impact of exploitativeactivitieslike shellfishharvesting
(an activitythat has recentlycausedsubstantialimpact on
waders and wildfowlin the hugelyimportantinternational
Wadden Sea - C. Smit, pers. comm.), tidal power,
'amenity'and storm surge barrages,waste disposaland
pollutant discharge, dock and harbour construction,
marina and recreationaldevelopments,channeldredging,
and drainage of inlandwetlands.
For an activitysuch as shellfishfarmingand harvesting
we need to know how damagingthis is to winteringbird
populations.The Ramsat Conventionrequires'wise use'
of our wetlands, so we need to know to what extent such
use of the limited resources
science.
activitiesare 'wise' in the sense of ensuringsustainable
use of the ecosystem. Is there a sustainablelevel of
harvestingthat providesfor birdsas well as for people?
Are some harvestingmethods more damagingthan
others? Is there a consistencyof effect and impact of the
activityon waders in differentparts of their flyway
perhapsdependenton densitiesof birds,or is such
impactentirelysite-specific?
In additionit is vital to considerthe patternsof impactof
human activitieson migratorybirds such as waders in the
broader contextof the impact on the habitats on which
such birdsdepend,and to understandthe human impacts
on the many otherwildlifefeaturesof these places.
Developingan effectiveconservationprogrammefor
these habitats is the mechanism through which
international
74
measures
available
for conservation
such as the 'Ramsar'
Convention
and the EEC Directive
on the Conservation
of Wild
Table 2. Internationalconservationmeasuresand agreements
Birds
relevant to waders and their habitats.
are effected. In Europe these measures provide
safeguardfor much larger areas of some habitattypes
Ao Worldwide
than will sites selected for their intrinsic habitat
Ramsar Convention(1971)
World HeritageConvention(1972)
CITES (1973)
Bonn Convention(1979)
importanceunderthe EC Directire on the Conservationof
Natural Habitats and Wild Flora and Fauna (Davidson &
Stroud 1995).
B. Europe/Africa/WestAsia
BerneConvention(1979)
EEC Wild BirdsDirective(1979)
African Convention(1968)
EEC Habitatsand Species Directive(1992)
African/EurasianWaterbirdAgreement(BonnConvention)
(1995)
Understandingimpacts on habitatsand developing
conservationsafeguardsfor these placesthus underpins
the safeguard of migratorywaders. Waders and other
migratorywaterfowlare very valuable linkinginternational
networksof these sites, and the continuedpresenceof all
of these networksites are essentialfor safeguardingthe
populations.
CONSERVING
FLYWAY
POPULATIONS
C. East Asia/Australasia
Bilateralagreements:
USA, Japan, China,Australia,India,ex-USSR
e.g. JAMBA (Japan-AustraliaMigratoryBirdsAgreement)
OF
WADERS
D.
Americas
Protectionof MigratoryBirdsConvention(1916)
Protectionof MigratoryBirds& Game Mammals
Convention(1936)
Western HemisphereConvention(1940)
US-JapanMigratoryBirdsConvention(1976)
US-USSR MigratoryBirdsConvention(1976)
Western HemisphereShorebirdReserveNetwork
(WHSRN) (1985)
NorthAmericanWaterfowlManagementPlan (NAWMP)
(1986)
Many countrieshave developedconsiderable
programmesof conservationeffortthat include
safeguardingmigratorywaders and their habitats. Some
of the site-based designationsand broader-based land
use and managementare operatedthroughdomestic
legislation. Others are implementedthrough the
applicationof non-statutorysafeguardsuch as nature
reservesmanaged by voluntaryconservationbodies such
as, in the UK, the Royal Societyfor the Protectionof Birds
(RSPB)•
There
Many countrieson wader flywaysalso apply domestic
conservationmeasures in responseto international
internationallaw such as the European Communities'
Directire on the Conservation of Wild Birds, and the more
on the Conservation
of Habitats
international
commitmentsrelevantto waders made by countries
throughoutthe world. These main international
designationsare listed in Table 2. Most measures lead to
the identificationand/or formal designationof sites
importantto waders duringtheir annual cycle, and some
requirethat these sites are the subjectof special
safeguardswithin a broader matrix of measuresto
safeguardbirdsthroughouttheir range and commitments
conventions such as Ramsar, Berne and Bonn, or
recent Directlye
are thus rather numerous
and
Species. Other internationalmeasures derive from
bilateralagreementsbetweencountriessharingmigratory
bird populations(see Biber-Klemm1991).
to the sustainable
One international wader conservation mechanism, the
use of wetlands
and their birds.
In a singlecountrythere can also be a multiplicityof
domestic site safeguard measures. These include:
Western HemisphereShorebirdReserve Network
(WHSRN) has become a highlysuccessfulinternational
non-statutorymechanism for raising support and
awarenessof the importanceof key wetland sites on the
flyways of American waders since its inceptionin 1985
(WHSRN 1990; Hunter et aL 1991). WHSRN now has
four categories of reserves: hemispheric,international,
regional,and endangeredspecies. By 1991 there were 12
hemispheric,four internationaland one regionalWHSRN
reservescoveringabout 1.5 millionha and supporting30
millionshorebirds. Reserve membershipis entirely
voluntary. Central to the networkis the understanding
that the conservationand managementof shorebird
habitat remains the responsibilityof the inhabitantsof the
regionin which the reserveis located.Within this
structurethere are three levels of site participation-
ß
statutorywildlife designationswhich in part are
designedto implement the international
commitments listed above;
ß
non-statutorywildlifedesignations,some of which
are sites owned or managed by voluntary
conservation bodies; and
ß
a variety of statutoryand non-statutorylandscape
designations,which providefor management
safeguardsin places of importanceto migratory
waders.
There are, for example, at least 18 differentwildlife and
landscapeconservationmeasures (some statutory,some
voluntary) relevantto the conservationof migratorywader
sites in Britain(Davidsoneta/. 1991). Many of these
have a complexrelationshipof overlappingboundaries
and are selected,designatedand managed by many
certified sites, dedicated sites, and secured sites -
affordingincreasinglevelsof voluntaryand sometimes
statutorysafeguard.
75
•
Pitiill of the•,,/-•
M
ImpO•tln!
bl•d
-,,•'lT•On
•outl
..'
...
i
We,JiemPalear•c Region
A,gllement
Parties
oftheBonn
ConvenOon
Figure
3. a). Parties
totheBonn
Convention
andthemost
important
migration
routes
(from
Boere
1991);
andb).theagreement
areaforthe
proposed
Western
Palearctic
Waterfowl
Agreement
(WPWA),
from
theNetherlands
Ministry
ofAgriculture,
Nature
Management
and
Fisheries
(1991) between
rangestatesoftheBonnConvention.
76
states can be party to the Bonn Conventionwithoutfull
membershipbeingin place. Legallybindingdirectives
such as those from the EuropeanCommissionapply to
only part of the range of most migratorywader
populationsduringtheir annual cycle - for example only
the winteringand/or staging areas of arctic-breeding
species. Furthermorethe applicationof common
conventionscan differ from place to place with differences
either in application,or in interpretation,of international
law and convention(Biber-Klemm 1991).
differentorganisations. Most countriesin Europe have
several categoriesof statutorywildlifeand landscape
conservationmeasures, althoughthe diversityand type of
designationvaries considerably(Figure 2).
The developmentand implementationof both
internationaland domestic conservationprogrammes for
migratorywaders is not, however,uniformthroughoutthe
flywaysof the world. Not all countrieshavejoined even
the most worldwide
of conventions
such as the 'Ramsar a
conventionor the Bonn Convention(Figure 3), although
•1
ßI 4•population
©
ß IQO ha
•
IQQI.OOQ
ha
•1
1.000I0,000
ha
e
I0.000I00.000
ha
//
>IQO.OOQ
ha
Figure4. The distribution
andsize designatedRamsarsites(wetlandsof international
importance)
that regularlysupportmorethan100 Knots.
Filledsymbolsshowsitesthatare internationally
important
for a Knotpopulation
(i.e. the sitesupports>1% of a biogeographical
population).
Notethat somesites supportKnotsin morethan one season,somesupportpopulationsof bothcanutusand islandicaKnots,and some provide
onlypartialcoverageforthe coastalsitesusedby Knots.
Little assessment has yet been made of the
consequencesof all this variability on the extent to which
wader flyways or individualwader speciesare afforded
safeguardthroughouttheir annual cycle. Stroud et aL
(1990) have assessedthe extentto which bird
populations,includingmany waders, would be includedin
the proposedSpecial ProtectionArea network (EEC Birds
Directive)in Great Britain. Davidson& Piersma (1992)
have recentlymade a first assessmentof the way in
which designationsof wetlands of international
importancehave been appliedto each Knot subspeciesat
differenttimes of year (Figure 4). This shows clearlythat
there are very great differencesin the extent to which
Ramsar site designationshave been made for different
subspecies,for differenttimes of year (breedinggrounds
are particularlypoorly covered) and for different stages of
the annual cycle of a single subspecies.
A broader
assessment
for Knots worldwide
safeguard(domesticand/or international)shows a similar
pattern of great variability within and between populations
(Figure 5). Some subspeciesare poorlysafeguardedby
site designationsat most or all times of year; for others
the extent of conservationcoverage is uncertain because
of the uncertainties
about the basic site locations
for the
population.
In parallel to the uncertaintysurroundingthe extent to
which conservationdesignationsapply to flyway
populationsof waders, there is no clear flyway
assessment of the extent to which all these designations
are successfulin providingsafeguardsfor the populations
they are designedto protect. Some informationis,
however, available for individual countries, and the
portentsare not good. For Britain, Davidsonet aL (1991)
have describedcontinuingloss and damage to many
nationallyimportantestuaries, and at rate twice that of
other habitatsin Britain. The presenceof a designatedor
proposed internationallyimportant site likewiseappears to
of the
proportionof each subspeciesat each stage in its annual
cycle that is afforded some form of conservation
be little deterrent
77
to further
habitat
loss since in 1989
over
one-half of Britain'sinternationallyimportantestuaries
faced land-claimproposalsthat if undertakenwouldlead
to furtherloss of habitat used by waders (Figure6). Many
other sites on wader flywaysworldwideare knownto be
sufferinghabitat loss and facingfurtherdestructionin the
Other recent internationaldevelopments(see also Salath6
1991a) includethe establishmentof an International
Wadden Sea Secretariat, proposalsfor an Action
Programmefor the conservationof wetlandsand
waterfowlin Southand West Asia (preparedat the
IVVRB/AVVB/Pakistan
future.
National
Council for the
Conservationof Wildlife 1991 Karachi Conference);an
East Asia Flyway Network co-ordinatedby the Asian
Wetland Bureau (AWB); and the IWRB/VVHSRN/Ducks
UnlimitedNeotropicalWetlands ProgrammeøAlongside
KnotCalidris
canutus population
coveraLe
--
these are numerous
islandlea
national
initiatives such as in the UK
the RSPB'sEstuariesCampaignand SpeciesActionPlan
programme,the JNCC Coastal Review(includingthe
NCC/JNCC Estuaries Review), and EnglishNature's
__
½allfltfl$
Estuaries
Initiative.
To summarise, ensuringthe long-term survivalof any
migratoryflyway needs compatible standardsto be
rogersi
appliedthroughoutits range,takingaccountof local
situations. To determine this, as with the first two
elementsof our strategy, requiresa reviewof
conservationeffectivenessalong the flyway. Again this
requiresco-ordinationand an aim of identifyingthe weak
links in the chain, both in terms of sites and of key
features of wader ecologyand flyway usage. Having
undertakenthis review,a programmeof actionto correct
such deficiencies could be implemented.
roselaari
•/•? ? 7 7 7
total species
Brccdln$.qmlgralmn'winter' N ml.•Tallofi
early late
early late
Some first steps in identifyingflyway featuresfor priority
actioncan already be attempted. We have, for example,
highlightedthe parts of the annual cyclefor one arcticbreedingmigrantwader for whichthere is littlesite
safeguard(e.g. duringthe breedingseason)- but note
that measures other than site safeguard are often more
appropriatefor conservingsuchwidelydispersed
populations.The prioritylistsof speciesprovidedby the
Figure5• Estimatedproportions
of Knotpopulations
occurringwithin
designatedconservation
sitesduringdifferentstagesof their
annualcycle. Conservation
designations
includebothdomestic
and internationaldesignations.The lightshadingfor breeding
canutusrefersto the recentlydesignatedGreatTaymyrReserve
whichcoversa substantialpartof theirknownSiberianbreeding
range(P. Prokosch,pers. comm.).
draft Western Palearctic Waterfowl Agreement
ManagementPlan (NetherlandsMinistryof Agriculture,
Nature Managementand Fisheries1991) permita
broader assessment
Perhapspartly in responseto these perceptionsof the
currentfailure of the many conservationdesignationsto
safeguardmigrantwaders, there are severalnew
conservationinitiativesunder development. Several of
these relate to the developmentof a co-ordinatingrole
through internationalmanagement plans. The IUCN, for
example,establishedin 1985 its globalwetlands
programme,and at aboutthe same time ICBP developed
its MigratoryBirdsConservationProgramme(Salath6
1991b, c).
of the characteristics
of the most
threatenedand vulnerablewader populationson the East
Atlanticand Mediterranean/WestAsian flyways. Of the
50 wader speciesand populationsin the Western
Palearctic31 (68%) are listedas threatened,rare,
decreasingor vulnerable,makingwadersamongstthe
higherrisk groupsof waterbirds(Table 3). Western
Palearcticwaders are thus in generalin need of priority
conservation
action.
Different'high risk'wader speciesand populationsoccur
in all breedingzones from arcticto temperate,dependon
all main types of winteringand stagingarea habitat and
use East Atlantic and Mediterranean-WestAsian Flyways.
it is interestingto note, however,also that widespread
species- those with major parts of their populationusing
in more than one breedingzone, non-breedinghabitat or
flyway are markedly less vulnerablethan those of more
restricteddistribution.This emphasisesthe importanceof
range conservationfor migratorywaders.
More recent,and of particularsignificanceto the flyway
conservation of waders, is the African-Eurasian Waterbird
Agreement(AEWA) currentlynearingcompletionunder
the terms of the Bonn Convention. This excitingnew
prospectiveagreement providesa mechanismfor coordinatingand linkingconservationaction on the two
majorwader flywaysin the westernPalearctic(Figure2),
and providesa frameworkfor developingconsistentsite
safeguardsand co-ordinatedspecies/population
conservationstrategies. Internationalmanagementplans
are also in preparationfor some other individualwaterbird
species,notablyon the White Stork Ciconiaciconia
(Goriup & Schultz 1991), and the GreenlandWhitefrontedGooseAnser albifronsfiavirostds(Stroud1992).
These provide useful models for potentiallywider use.
78
not seem to be suitable large areas of alternative breeding
Table 3. The percentageof variousgroupsof waterfowl
populations
and speciesin the Western Palearcticthat
believedto be in an unfavourablestate. Species and
populationsare includedas in an unfavourablestate if theyare
listedas threatened,rare, decreasingor vulnerablein the
Western PalearcticWaterfowlAgreementDraft Management
Plan (NetherlandsMinistryof Agriculture,Nature Management
and Fisheries1991).
habitats
waders
68
divers& grebes
cormorants,herons,egrets,
73
70
84
ducks
rails
58
57
gulls & terns
65
on which
Much is already being done to promote the conservation
of migratorywaders, but many populationsremain
vulnerableand face apparentlyincreasingthreats to their
continued health. To put in place a conservation
programme for the future, we need to take a number of
key steps. These are:
state
a. identifywhat we do not know aboutthe basic biologyof
the species and fill the gaps, highest prioritiesfirst;
storks etc.
swans & geese
and inland wetlands
so many populationsdepend for their winter survival.
Indeed many of the wader populationsthat currently use
these places throughout Europe are in serious decline
largely through habitat destruction(H0tker 1991). Hence
destructionof key elements in migratory wader flyways
would mean the destructionof the species.
% of spp./population
in
unfavourable
around the coastal
b. identifywhich human impacts are having an adverse
impact and quantifysuch impacts along the flyway.
When gaps in our knowledgeare identifiedthey need
to be filled; and
c. identifythe current level of conservationaction along
the length of the flyway, determine its effectiveness
and set about enhancing conservationaction where it
is seen to be inadequate.
Internationally
67with
noproposals
(43%)
•-•--•
importam
estuaries
33 with no
Undertakingthese steps, on a worldwide basis or even for
a singleflyway, will involveconsiderablework requiring
both collation and reappraisal of existing informationand
collectionand collationof further informationwhere gaps
,:-.•?
;..•ais
(?.1%)
are identified.
19with
proposals
(12%)
Such assessments are unlikelyto fall easily within the
scope of individualorgamsations,whether national or
international. Many of the major advances in our
understandingof migratorywaders have come from
internationalcollaborationby wader-workersand
conservationists. It is appropriateto develop such future
work vital for the safeguardof migratorywaders as
internationalco-operativeexercises.
36with
proposals
(23%)
We suggestthat to take this internationalflyway
collaborationforward, projectscould includethe following:
Figure6. Proportions
of internationally
important,and other,British
estuariesaffectedby land-claimproposalsin 1989, from
Davidsonet al. (1991).
a.
FUTURE
DIRECTIONS
CONSERVATION
FOR MIGRANT
WADER
Migrationand flyway use reviewsfor individual
species and populations,includingworldwide
appraisals. A model for this could be the WSG Bulletin
Supplementon Knot migrationworldwide.
b. Reviewsof individualflyways,drawingin part on
individualspecies reviews and how the patterns of use
by many differentspecies combine to give the overall
flyway picture. Elements of such reviews appear
already in many guises, includingthe WSG Bulletin
Supplementon flyway conservation,the various
papers in Salath6 (1991), IWRB wetland inventories,
the WPWA and action plan, the Canadian Wildlife
Service'sSouth American shorebirdatlas (Morrison&
Ross 1990), IWRB flyway populationreviews(e.g.
Smith & Piersma 1989) and reviews such as NCC's
Estuaries Review (Davidson et al. 1991). An
internationalprojectcompilingflyway characteristics
for each differentmigratorywader speciesand
Wader (and other waterfowl) migratoryflyways are one of
the world's biologicalwonders. The maintenance and
enhancement of these populationsthrough appropriate
conservationmanagementof the habitats uponwhich
they depend shouldbe a global conservationpriority.
Some migratoryorganisms may be able to survive even
after being forcedto abandontheir migratoryhabitats
through,for example, removalof key sites in a migratory
network. Many migratorywader populationswould,
however,seem unlikelyto be able to adopt rapidlya nonmigratorylifestyleshouldkey sites in their flyway network
be removed. Such removal would prevent the
populationsfrom moving betweentheir breeding and
wintering grounds: arctic-breedingspecies could not
survivethere through the arctic winter, and there would
79
populationin now beingdevelopedthroughthe Wader
Study Group.
c.
InternationalWader Studies). There is great scopefor
this role to continue,for examplethroughthe collaborative
preparationof furtherIWS volumes. Some are alreadyin
preparation,notablyon shorebirdecologyand
conservationin the Western Hemisphere(from the 1991
Quito symposium),American Great Basin shorebirds,and
wader researchand conservationon Europeanand North
Asian flyways(based on the 1992 internationalWSG
conferencein Odessa, Ukraine).
Comparativeassessmentof human activities,threats
and impactsfor all parts of a flyway• A model is the
basicallysimple data collectionmethodology
developedfor the NCC Estuaries Review (Davidsonet
al. (1991), now being developedby the UK Joint
Nature Conservation
Review.
Committee
as a national Coastal
For a first phase of futuredevelopmentWSG has
identifiedthe followingprojects,on which collaborationis
d. Reviewsof the flyway-widepatternsof conservation
designationsfor individualspecies,for wader
assemblagesand at differentparts of the annual cycle.
e.
f.
sought:
1. Collationand analysisof the patternsof human
Preparationof speciesconservationand management
strategies,based on the types of informationgathered
in a. - d. above. Such strategiesmight be developed
underthe auspicesof the Bonn ConventionAEWA.
There are a numberof modelsfor this approachin
waterfowl,includingthe AEWA White Stork
conservationmanagementplan (Goriup & Schultz
1991), and the GreenlandWhite-fronted Goose
InternationalConservationPlan (Stroud 1992). A
possiblefirst target for such a strategyfor waders
could be the Knot,for which much factual preparatory
work is available(Piersma & Davidson1992; Piersma
1994).
activities and threats to wader habitats in the Western
Palearctic.
Preparationof wader conservationstrategiesfor
differentflyways, e.g. for the East Atlantic and/or the
Mediterranean/WestAsian flyways,and for countries
within flyways, e.g. the recent nationalplan for
shorebirdconservationin Australia(Watkins 1993);
2.
Developmentof an internationalflyway conservation
plan for wader speciesand populations,with the
preparationof the first such plan for the Knot.
3.
Encouragmentof individualsand collaborativegroups
in the preparationof wader species information
reviews,as the essentialprecursorto developing
furtherflyway conservationplans. Two furtherspecies
reviews, on Dunlins Calidrisalpinaand KentishPlovers
Charaddusalexandrinus,are now being preparedfor
IWS publication.
We would welcome comment on these suggestions,and
on how such futurewader flywayconservationmightbe
best achieved. In particularwe would like to hear from
anyone wishingto be involvedin such projects,and those
who may be able to arrangefor the provisionof resources
and
to undertake
g.
Establishmentof a Western Palearctic wader reserve
network,perhapsalongthe lines of the Western
HemisphereShorebirdReserve Network. An East
such work.
For some of these initiativesit may be mosteffectiveto
undertakepilot developmentof the approachusingsome
simplerand/or betterknownsystems(suchas developing
a flyway conservationfor the Knot), as well as targeting
those speciesand issuesfor which urgentactionis
believednecessaryand for which little is known.
It is perhapsfittingthat these ideas for futurewader
flyway actionwere first presentedat a uniquely
international wader conference, held in Odessa, Ukraine,
situatedin the heart of majorwader stagingareas on the
Mediterranean/WestAsian Flyway,and at a time of year
(April)when manythousandsof waderswere passing
throughen route to relativelylittle-knownbreeding
groundson a poorly-understood
migrationroute. Many of
the approachesproposedin this paperare also
incorporatedin the Odessa Protocolon internationalcooperationon migratoryflywayresearchand conservation
(Wader Study Group 1992), developedat that conference
Many organisationsand groupscouldbe key participants
in co-ordinateddevelopmentof some or all of these
ACKNOWLEDGEMENTS
Asian-Australasian
shorebird reserve network is now
beingdeveloped,as are proposalsfor developing
worldwide
features.
networks.
For the Western Palearctic these could include
WSG, IWRB, Ramsar Bureau,ICBP, IUCN, VVVVF(e.g.
VVVVF-Wattenmeerschelle
Schleswig-Holstein),
the
We thank David Stroud, Hermann Hdtker and Janine van
Vessem for helpfuldiscussionsand commentson earlier
draftsof this paper.
InternationalWadden Sea Secretariat, RSPB, JNCC, the
EuropeanUnionfor CoastalConservation(EUCC) and
the RussianWader StudiesGroup as well as
knowledgeable
wader-workersthroughoutthe flyways•
REFERENCES
WSG has an extremelyvaluableroleto play is all this,
Baker,A.J., Pierstoa,T., & Rosenmeier,L. 1994. Unravelingthe
intraspecific
phylogeography
of knotsCalid#scanutus:a
progressreporton the searchfor geneticmarkers. In:
Piersma,T. Closeto the edge: energe#cbottlenecksand the
evolutionof migratorypathwaysin Knots:39-45. PhD.
Thesis,Universityof Groningen.
since its informal international links with those active in
the fieldsof wader researchand conservation
in many
countrieshave acted as the catalystto the collationand
publicationof much vital backgroundinformationboth as
materialin its regularBulletinsand compiledon special
topicsin its SupplementSeries(now publishedas
8O
Meltofte, H., Blew, J., Frikke, J., R0sner, & Smit, C.J. 1994.
Biber,J.-P. & Salath•, T. 1991. Threats to migratorybirds. ICBP
SpecialPublicationNo. 12:17-35.
Numbers and distribution of waterbirds in the Wadden Sea.
IWRB Publ. 34/Wader Study GroupBull.74, SpecialIssue.
Biber-Klemm,S. 1991. Internationallegal instrumentsfor the
protectionof migratorybirds: an overviewforthe West
Palearctic-African
Flyways.ICBP SpecialPublicatiot•
Now12:
NetherlandsMinistryof Agriculture,NatureManagementand
Fisheries.
1991.
Final draft of the Western Palearctic
WaterfowlAgreementand ActionPlan withExplanatoryNotes
and ManagementPlan. Ministryof Agriculture,Nature
Managementand Fisheries(Directoratefor Nature
Conservation,EnvironmentalProtectionand Wildlife
Management),Gravenhage,The Netherlands.
315-344.
Bildstein,K.L., BancroftG.T., Dugan,P.J., Gordon,D.H., Erwm,
R.M., Nol, E., Payne,L.X. & Senner,S.E. 1991. Approaches
to the conservation of coastal wetlands in the Western
Hemisphere. WilsonBull. 103: 218-254.
Piersma,T. 1986. Breedingwadersin Europe. Wader Study
Group Bull. 48, Suppl.
Boere, G.C. 1991. The Bonn Conventionand the conservationof
migratorybirds. ICBP TechnicalPubl. Nos12: 345-360.
Boyd,H. & Pirot,J.-Y. 1989. Flywaysandreservenetworksfor
waterbirds. IWRB SpecialPublication
No. 7.
Piersma,T. 1994. Close to the edge: energeticbottlenecksand the
evolutionof migratorypathwaysin Knots. PhD. Thesis,
Universityof Groningen.
Davidson,N.C. & Pienkowski,M.W. 1987. The conservationof
international
flywaypopulationsof waders. Wader Study
GroupBull. 49, Suppl.//WRBSpecialPublicationNo. 7.
Piersma,T. & Davidson,N.C. 1992. The migrationof Knots. Wader
Study GroupBull.64, Suppl.
Prater,A.J. 1981. EstuaryBirds. T. & A.D. Poyser,Calton.
Davidson,N.C., Laffoley,D.d'A.,Doody,J.P., Way, L.S., Gordon,J.,
Key,R., Drake,CM., Pienkowski,
M.W., Mitchell,R. & Duff,
K.L. 1991.
Salath•,T. (ed.) 1991a. ConservingMigratoryBirds. ICBP
Techinical Publ. No. 12. International Council for Bird
Nature conservation and estuaries in Great B#tain.
preservation•
Cambridge.
NatureConservancyCouncil,Peterborough.
Davidson,N.C. & Piersma,T. 1992. The migrationof Knots:
conservationneedsand implications.Wader Study Group
Bull. 64, Suppl.:198-209.
Salath•, T. 1991b. The ICBP MigratoryBirdsConservation
Programme.ICBP TechincalPubl.No. 12: 3-14•
Salath•, T. 1991c. Forwardplanforthe ICBP MigratoryBirds
Conservation
Programme(West Palearctic-African
Flyways.
ICBP TechnicalPubl. No. 12: 383-393)
Davidson, N.C. & Rothwell, P.I. 1993. Disturbance to waterfowl on
estuaries. Wader Study GroupBull.65, Suppi.
Smit, C.J., Lainbeck, R.H.D. & Wolff, W.J. 1987. Threats to coastal
Davidson, N.C. & Stroud, D.A. 1995. Internationalcoastal
winteringand stagingareasof waders. Wader StudyGroup
Bull.49, Suppi./IWRBSpecialPublication
No. 9: 24-63.
conservation:
conservingcoastalhabitatnetworkson migratory
waterfowlflyways. In: A.H.P.M Salman,H. Berends& Mo
Bonazountas(eds.), Coastal Management and Habitat
Stroud,D.A., Mudge,G.P. & Pienkowski,M.W. 1990. Protecting
internationally
importantbirdsites. NatureConservancy
Council,Peterborough.
Conservation: 177-199. EUCC, Leiden.
Finalyson,M. & Moser,M. 1991. Wetlands. Factson File, Oxford.
Stroud, D.A. 1992. GreenlandWhite-frontedGoose Anser albifrons
fiavirostrlsInternationalConservationPlan. Draftworking
document:full plan,versionJanuary1992. NationalParks&
Wildlife Service, Ireland/IWRB.
Gill, R.E., Jr., Butler, R.W., Tomkovich,P.S., Mundkur, T. & Handel,
CM.
1994.
Conservation of North Pacific Shorebirds.
Trans.
59th North Am. Wildl.& Natur. Resour. Conf. (1994): 63-78.
[Reprintedthis WSG Bulletin].
Tiner, R.W. 1984. Wetlands of the United States: current status
and recent trends. US Fish & Wildlife Service, National
Wetlands Inventory.
Goriup,P.D. & Schultz,H. 1991. Conservation
managementof the
White Stork:an international
needand opportunity.ICBP
Technical Publ. No. 12:97-127.
Watkins, D. 1993. A nationalplanfor shorebirdconservationin
Australia. RoyalAustralasianOmithol.UnionReportNo. 90.
RAOU, Melbourne.
Grimmett,R.F.A., & Jones,T.A. 1989. Importantbirdareas in
Europe. ICBP TechnicalPub/.9.
Hayman,P., Marchant,J. & Prater,A.J. 1986. Shorebirds.An
identificationguide to the waders of the world. Croom Helm,
London& Sydney.
Western HemisphereShorebirdReserveNetwork,1990. Going
global. Conservation
and biologyin the WesternHemisphere.
WHSRN NetworkNews 3(2-3): 1-11.
H0tker, H. 1991. Waders breedingon wet grasslands. Wader
StudyGroupBull. 61, Suppi.
Hunter,L., Canevari,P., Myers,J.P. & Payne,L.X. 1991. Shorebird
andwetlandconservation
in the Western Hemisphere.ICBP
Technical Publ. No. 12: 279-290.
Kirby,J.S., Waters, R.Jo& Prys-Jones,R.P. 1992. Wildfowland
wader counts 1990-1991. Wildfowl & Wetlands Trust,
Slimbridge.
Lane, B.A. 1987. Shorebirdsin Australia. Nelson, Melbourne.
Lane, B.A. & Parish, D. 1991. A reviewof the Asian-Australiasian
birdmigrationsystem. ICBP TechnicalPubl.No. 12: 291312.
81