Migration of Red Knots in South America 1996-2000: ecological research to support the conservation of the longest bird flights on earth

A co-operativeresearch and conservationproject of the Wader Study Group, under auspices of Wetlands for the Americas

This proposaloutlines a co-operativeresearch program investigatingthe ecologyof migration of an extreme long-distanceand relativelyuncommon migrating shorebird,the Red Knot Calidriscanutus rufa. This wader connects,in the courseof its annual migrations,a limited numberof coastalwetlands in South America. The proposedprogram of work buildson the localexpertise and a seriesof shorebird-benthosresearch projects already beingcarried out by a variety of organizationsand institutionsin ,Uruguay and Brasil. The three year project(hopefully running from January 1996 through May 1998) aims: (1) to furtherthe understandingof the biologyof Red Knotsin a comparativeworldwide framework; (2) to bring a commonand biologicallyimportant theme to the variety of investigations already underway; (3) to deliverfunds to allow more detailedand higherquality, fieldwork and laboratory analyses; (4) to integratepreliminary results in each year of the project;and (5) to bringtogether, in 1999 or 2000, all participantsand the digestedresults in a workshop aiming at a synthesisof achievements. This shouldresult in a publicationin the InternationalWader Studiesseries, in which new discoverieson the migration,ecology and resourcebasis of the migrationof Red Knotsin SouthAmerica are summarized,and in whichthe conservationand managementimplications are outlined. We are currentlysearching for about $US 120,000, the greatestportion of which ($US 90,000 in total, or $US 30,000 per year) will be devotedto the cost of carryingout fieldworkin various places. The remainingsum will be neededfor the workshop,its organizationand logistics,and the publicationand disseminationof results.

INTRODUCTION result of a populationbottleneck at the end of the last Ice Age in the early Holocene(Baker et al. 1994). This lack of The Red Knot Calid#s canutus is a remarkable shorebird geneticvariability (especially as it relates to issues of species. They occurthroughout the world, usuallyalong disease resistance,immuno-competence) could in coastalshores, where they usuallyfeed on small-hard- principleaffect the ability of the speciesto cope with new shelled molluscswhich they ingestwhole and crush in environmental stresses. their strong muscular gizzard. In order to move between their favourite coastal haunts, Red Knots breed around the North Pole on high arctic Red Knotsmake the longestnon-stop flights known in the tundra, with birds from the different polar regions avian world (possiblyup to 8,000 km). Their migrations migratingto differenttemperate and tropicalwintering have become relativelywell describedbecause of a large areas. This substructuringof the world'sRed Knots has interestfrom the amateur ornithologicalcommunity, often led to several marked morphologicaldifferences, and thus working in collaborationthrough the internationalWader in the recognitionof five separate races or subspecies. Study Group (WSG). At the same time, the biologyof Red Knotsseem to be geneticallyimpoverished as the Red Knots has becomethe focus of professional biologicalattention at research institutions,their biologists

40 workingin close and productiveco-operation with the the degreeof flexibilitythat these birdsmay have in their amateur workers(e.g. Piersma & Davidson1992). choiceof winteringareas. It will also highlightthe differentialimportance of individualsites withinthe Red Knotsare well recognizedas a promisingkey-species networkused. Red Knotsmay thus providea key or 'Vehicle" to make the case for the world-wide illustrationof the criticaldependence of migratory conservationof biologicallyconnected coastal wetlands waterbirdson chainsof highquality sites and their story and tundra areas (e.g. Davidson& Stroud 1995). thus stronglysupport the conservationof individualsites and seriesof wetlands- the main objectiveof the Western Of the five recognizedsubspecies, there are two which HemisphereShorebird Reserve Network (WHSRN). spendthe non-breedingseason in SouthAmerica. The subspeciesroselaari has been describedonly a decade WHSRN, a projectof Wetlandsfor the Americas(WA) ago. It breeds In Alaska and on Wrangel Island and may worksto identifycritical wetland stopover sites and bring winter in Florida and further south in Central America and them into an international network, in which habitat northof South America (Pierstoa & Davidson1992). The protectionis fosteredthrough voluntary commitments to subspeciestufa breedsin the Canadian arctic and spends long-termmanagement to benefitshorebirds and many the non-breedingseason at the tip of the SouthAmerican otherspecies. WHSRN also helpsin environmental continent,in southernPatagonia and Tierra del Fuego education,research and the "twinning"of geographically (Morrison& Harrington1992). This subspecies distantreserves that hostthe same species. undertakesthe longestoverall migrationand the longest singleflights, and is peculiarin that it migratesfrom the energeticallycostly coldness of the Canadian high arctic RED KNOTS IN SOUTH AMERICA summer into the cold of the subantarctic. The Red Knotsthat go to South America to survivethe The overall pattern of the migrationsof Red Knotsis thus northernwinter, breed in the Canadian arctic(Morrison & sufficientlywell describedto allow deeperquestions about Harrington1992; Harrington1995). its migrationto be asked; questionswhich may be critical for the developmentof soundinternational management They leavethese areas in July and earlyAugust, and strategiesfor this and other shorebirdspecies. There are assembleon the westernshores of James Bay before a few ecologicalcharacteristics that make Red Knots movingon to the Maritime Provincesof Canada and the suitablefor large-scaleinvestigations on the causesand shoresof New England, beforetaking off on a major flight consequencesof long-distancemigration: they usuallyeat over the Atlantic Ocean to the shores of Surinam. From molluscs,about which the criticalecological here they rapidlymove on to southernmostSouth characteristics(abundance, availability, seasonality) can America, south and Tierra del Fuego, where quite easily be collected. Diet can easilybe described they arrive in late October and November. In Tierra del from faecal analyses(Dekinga & Piersma 1993) and food Fuegothey first go througha completebody and wing intake rates can be measured(Zwarts et al. 1992). There molt, finishingin January,and almost immediatelystart is a large backgroundliterature from Europeand Africafor preparingfor their northwardmigration by moltinginto a comparativepurposes, which also allowstheoretical new breedingplumage in February. explorationsinto energy expenditureas a functionof climateand activitylevels (Piersma 1994; Wiersma & Their northwardmigration begins in mid February. Red Piersma 1994). Knotshave been observedon passagein Argentinaat PeninsulaVald6s (Morrison& Harrington1992), coastal A furtherbonus of the migrationsof the tufa subspeciesin sites in BuenosAires Province(Myers & Myers1979), SouthAmerica is the scale of movementsthrough several Punta Rasa (Blanco et al. 1992), and Bahia climaticregions and over large distanceseven within Samboromb(Sn(Vila et al. 1994). Only recentlyhas the singlecountries (Argentina, Brasil). The presenceof importanceof the region of San Antonio Oeste, in the competentobservers along this well definedmigration north-westcorner of Golfo San Mat[as, been recognized routesmake it very attractiveto studythe ecological (Gonzalez 1991; Gonzalez et al. MS). Furthernorth, causes and consequencesof this migrationpattern, and passagebirds are seen in the northof Uruguay(Vaz- the role that the different coastal wetlands in South Ferreira1961) and in southernmostBrasil (Harrington et Americafulfil for this species. Since we regardthe case al. 1986) (e.g. Lagoa do Peixe in Rio Grandedo Sul), of the Red Knot as typicalof all other migratingshorebird wherethey preparefor the big leap northwards,the 5,000- species,a detailedintegrated study of their movements 8,000 km long flightsover the Amazon Basinand the Gulf and ecologyshould yield insightsfor conservationthat of Mexicointo Delaware Bay, USA. Here, for three weeks extendfar beyondthis singlespecies. in May, Red Knots feast on the masses of Horseshoe Crab-eggsthat accumulateon the beaches,before We proposeto make a detaileddescription of the pushingon to the Canadian arctic breedinggrounds in the movementsof Red Knotsbetween sites (spatial dynamics last days of May. and chronologyin relationto fuel storageand molt), in conjunctionwith an elucidationof the resourcebase (food and feeding). This will enable us to gain an understanding of the constraintson bird movementswithin the range of availableSouth Americanwetlands, and yield insightsinto

41 SCIENTIFIC AND CONSERVATION INTEREST IN The followingconservation initiatives are underwayin RED KNOTS AND THE WETLANDS THEY VISIT areas where studies of the migration of Red Knots are proposed: The followingresearch initiatives have already been carried out, or are in operation, in the region covered by (1) Creation of the Reserva Costa Arianfica de Tierra this project: del Fuego,Argentina by the provincialgovernment of Tierra del Fuego, and recognitionas a (1) The Knot migretionproject 1990-1992 carriedout 'hemisphericsite' by WHSRN in December 1992. by GrupoArgentino de Limicolas;(co-ordinated by Patricia M. Gonzalez, San Antonio Oeste, and (2) Integratedmanagement project of the Patagonian Daniel Blanco,). coast, fundedby the Global EnvironmentalFacility of World Bank and implementedby Fundaci(Sn (2) Studies on abundance and distribution of Red Knots Patagonia Natural. in Tierra del Fuego Province,January 1995; (Wetlands for the Americas, BuenosAires, in co- (3) Creation of the Natural Protected Area Bahia de operationwith the provincialgovernment of Tierra San Antonioby the provincialgovernment of Rio del Fuego and partly funded by the Global Negro in July 1993 and recognitionas an EnvironmentalFacility of the World Bank). 'internationalsite' by WHSRN in August 1993.

(3) Ecologyand populationgenetics of Red Knotsin (4) The establishementof a provincialreserve Tierra del Fuego Province,February 1995; (co- managed by the National Park Administration ordinatedby Allan J. Baker, Royal Ontario Museum, coveringaround 10% of the coastal lagoonof Mar Toronto). Chiquita, BuenosAires Province. Attempts are made to increasethe protectionby agreementwith (4) Studieson food abundanceand feedingof Red the private landowners. Knots in the contextof the entire annual cycle in Golfo San Jos•, ;(Gustavo (5) A few private refugesand a plan for a provincial Pagnoni & Dr Luis Bala, Centro Nacional reserve have or are being establishedat Punta Patag(Snico,Puerto Madryn). Rasa, Bahia Samboromb(Sn. Also, there is a biologicalstation managed by the Fundaci(SnVida (5) Studieson abundance,food and feedingof Red SilvestreArgentina. Knots at San Antonio Oeste, Rio Negro Province; (Patricia M. Gonzalez, Direcci(Snde Fauna de Rio (6) The BuenosAires ProvinceGovernment is working Negro, San Antonio Oeste)o to incorporetefour coastal wetlands sites into the Ramsar Convention,two of which (Bahia (6) Ecologicalstudies of shorebirdsand benthic Samboromb(Snand Mar Chiquitacoastal lagoon) communitiesin Samboromb(SnBay and Mar are importantfor the Red Knotsmigration. ChiquitaCoastal Lagoon,Buenos Aires Province; (Mariano Martinez &Dr. Oscar Iribarne,Universidad (7) The establishmentof a NationalPark in Lagoa de Nacionalde Mar del Plata, Mar del Plata). Peixe, Rio Grande do Sul, in 1986, which was subsequentlyrecognized as an 'internationalsite' by (7) Studieson the migrationof Red Knotsat Punta WHSRN in September 1990, and as a Ramsar site Rasa, Buenos Aires Province, as well as studies on in 1993. the local benthicfood resources;(co-ordinated by Daniel Blanco, Wetlands for the Americas, Buenos (8) The establishment of an Area of Environmental Aires). Protection in Reentrancias Maranhenses, Marenhao, in June of 1991, which was (8) Researchon the migrationof Red Knotsin Lagoa subsequentlyrecognized as an 'hemisphericsite' by de Peixe, Rio Grandedo Sul, since 1984; (Paulo WHSRN in December 1991. Antas & In•s do Nascimento from CEMAVE, Brasilia,and Brian Harringtonand co-workers, Manomet Bird Observatory,Manomet), PROPOSED RESEARCH SITES AND RESEARCH (9) Studieson the migretionof Red Knotsat PARTNERS ReentranciasMaranhenses, Maranh•o; (Antonio AugustoFerreira Rodrigues,Universidade Federel (1) Rio Grande, Tierra del Fuego, Argentina Do Maranhao,Sao Luis). (M. Silvina Ramirez, Dir. Gral. de Medio Ambiente, Rio Grande;Luis G. Benegas,Museo de Cs. (lO) MonitoringRed Knot migrationthrough Brasil by Naturales, Munic. de Rio Grande; Rub•n CEMAVE since 1984; (co-ordinatedby In•s do Manriquez, Dir. Gral. de Medio Ambiente, , Nascimentofrom CEMAVE, Brasilia). Argentina).

42 (2) Bahia Bustamente and Comodoro Rivadavia, SUPPORTING ORGANISATIONS Chubut, Argentina (M6nica Abril and co-workers, Asoc. Patag6nicade Ornitologia,Comodoro (1) Wetlands for the AmericaslHumedales para las Rivadavia,Argentina). Americas, throughthe Western Hemispheric Shorebird Reserve Network, Ottawa, Canada. (3) Peninsula Vald•s, Chubut, Argentina (Gustavo Pagnoni& Luis Bala, CentroPatagbnico, Puerto (2) Manomet Observatory for Conservation Madryn, Chubut,Argentina). Sciences, Manomet, Mass, U.S.A.

(4) San Antonio Oeste, Golfo San Mafias, Rio (3) Fundaci6n Patagonia Natural, PuertoMadryn, Negro, Argentina (PatriciaM. Gonzalez& co- Chubut,Argentina. workers,Dir. de Fauna de Rio Negro;Carolina Belenguer& Pablo Petracci,Grupo Becasa, Bahia (4) Grupo Argentino de Limicolas, BuenosAires, Bianca,Argentina). Argentina.

($) Mar Chiquita coastal lagoon, Buenos Aires (5) CEMAVE, Brasilia,Brasil. Province, Argentina (Mariano Martinez& Dr Oscar Iribarne, Univ. Nacional de Mar del Plata, (6) ProAves, Brasilia,Brasil. Mar del Plata, Argentina). (7) CWS Latin American Program, CanadianWildlife (6) Punta Rasa, Buenos Aires Province, Argentina Service, Ottawa, Canada. (Daniel Blanco,Wetlands for the Americas,Buenos Aires, and co-workers of the Fundaci(SnVida SilvestreArgentina, Buenos Aires, Argentina). FINANCES (7) Barra del Chuy, Uruguay (AdrianStagi & coworkers, GUPECA and Universidad Nacional del The budgetof $US 20,000 comprisestwo main items of Uruguay,Montevideo, Uruguay). differenttemporal priority. The first priorityis $US 90,000 to coverthe expensesfor fieldwork. The financial (8) Lagoa de Peixe, Rio Grande do Sul, Brasil (In•s requirementsfor organisingthe workshopand the do Nascimento and coworkers, CEMAVE, Brasilia, publicationof the resultscan be consideredin the Brasil). followingyears.

(9) Reentrancias Maranhenses, Maranhiio, Brasil 1) Money for field work by the differentgroups. The (AntonioAugusto Ferreira Rodrigues, Universidad amounts can very considerablydepending on the de Maranh•io, Sao Lu[s, Brasil). scale of the work, the frequencyof field trips, the distancesbetween field and laboratorysites, and the amount of local support. The total is $US 90,000 or about $US 30,000 per year, includingthe ORGANISATION runningof the co-ordinationin San AntonioOeste.

Given the big geographicaldifferences, the variousteams 2) Moneyfor a joint workshopin 1999 includingthe will work quiteindependently, all havingtheir separate financesto bringparticipants together, for goals. Commonresearch methodologies and finances,as organisationalarrangements, and for the well as the bringingtogether of analyseddata for publicationof the resultsas an issue of the purposesof synthesis,are co-ordinatedby Patricia M. International Wader Studies, a refereed new Gonz.•lez of the Direcci6nde Fauna de Rio Negro in San publicationseries of the internationalWader Study AntonioOeste, Argentina. Patriciawill make surethat the Group. methodologyis sufficientlyuniform at sites and that informationabout problemsand progressis exchangedon At this momentwe are lookingfor two suitable'parent a regularbasis. She will also managethe budget. organisations'(one non-governmentalorganisation in Patricia is supportedby the field groupson one side, and Argentinaand anotherin Brasil)through which we can a groupof six Councillors(listed below) on the other. arrangethe fundraisingand the financialarrangements followingfrom it. The co-ordinationof bandingand colour-markingat the differentsites, will be undertakenby In•.sdo Nascimento of CEMAVE in Brasilia, Brasil. CEMAVE will make COUNCILLORS availabletheir expertiseon individualcolour banding. In•.swill helpwith the generalco-ordination of activitiesin Brasil. We hopeto organizea Workshopin 1999 or 2000 To supportand guidethe individualresearchers and the at the CentroPatagonico in PuertoMadryn, Chubut, projectco-ordinators, the followingsix individualshave Argentinawith supportfrom Dr Luis Bala and Gustavo agreedto take on responsibility: Pagnoniof that institution.

43 Prof. Dr Allan J. Baker, Department of Ornithology,Royal Harrington,B.A. 1995. Flightagainst time. The endlesssp•fng and Ontario Museum, Toronto, Ontario M5S 2C6 Canada summerof the Red Knot. WGBH, Boston. Hardngton,B.A., de TarsoZuquim Antas, P. & Silva,F. 1986. Prof. Dr Enrique Bucher, Universidadde C6rdoba / Northwardshorebird migration on the Atlanticcoast of Wetlands for the Americas, C.C. 122, 5000 C6rdoba, southernBrazil. Vida SilvestreNeotropical 1: 45-54. Argentina. Morrison,R.I.G. & Harrington,B.A. 1992. The migrationsystem of the Red Knot Calidris canutus rufa in the New World. Wader Pablo Canevari, Wetlands for the Americas (WA), Study GroupBull. 64, Suppl.:71-84. Monroe 2142, (1428) Capital Federal, Argentina. Myers,J.P., & Myers, L.P. 1979. Shorebirdsof coastalBuenos Aires Province. Ibis 121: 186-200. Dr Gonzalo Castro, World Wide Fundfor Nature (WWF), 1250 Twenty-FourthSt., NW Washington, D.C. 20037- Pierstoa,T. 1994. Close to the edge. Energeticbottlenecks and the evolutionof migratorypathways in Knots. UitgeverijHet 1175, U.S.A. Open Boek,Den Burg,Texel.

Brian Ao Harrington, Mahomet Observatoryfor Pierstoa,T. & Davidson,N.C. 1992. The migrationsand annual Conservation Sciences, P.O.Box 1770, Manomet, cyclesof fivesubspecies of Knotsin perspectiveøWader StudyGroup Bull. 64, Suppl.187-197• Massachusetts 02345, U.S.A. Vaz-Ferreira,R. 1961. Aves nuevaso pococonocidas en la Dr Theunis Piersma, Wader Study Group (WSG) and Rep[3blicaOriental del Uruguay. Com. Zoo/. Museo Hist. Nat. Netherlands Institutefor Sea Research (NIOZ.), c/o P.O. Montevideo92 (V), 76 pp. Box 59, 1790 AB Den Burg, Texel, The Netherlands• Vila, A.R., Bremer,E.R. & Beade,M.S. 1994. Censosde chorlosy playerosmigratorios en la Bah/a de Samborombdn,Provincl• de BuenosAires, Argentina. BoletinTc•cnico de la Fundaci6n Vida SilvestreArgentina, Buenos Aires. REFERENCES Wiersma, P. & T. Pierstoa. 1994. Effects of microhabitat,flocking, Baker,A.J, Piersma,T. & Rosenmeier,Lo 1994. Unravelingthe climateand migratorygoal on energyexpenditure in the annual intraspecificphylogeography of KnotsCalid•fs canutus: a cycleof Red Knots. Condor96: 257-279o progressreport on the search for geneticmarkers. J. Ornithol. Zwarts, L., A.-M. Blomert& J.H. Wanink. 1992. Annual and 135: 599-608. seasonalvariation in the foodsupply harvestable by Knot Blanco,D.E., Pugnali,G.D. & RodriguezGot•i, Ho 1992. La Calidriscanutus staging in the Wadden Sea in latesummer. importanciade Punta Rasa, Peia de BuenosAires, en la Mar. Ecol. Prog. Ser. 83:129-139. migraci6ndel chorlorojizo, Calidris canutus. El Hornero3: 203-206. CORRESPONDENCE Davidson,N.C. & Stroud,D.A. 1995. Conservinginternational coastalhabitat networks on migratorywaterfowl flyways. J. Coast. Conserv.: in press. Patricia M. Gonz,•lez, Direcci6n de Fauna, Ministerio de Economia, C.C. 84, Pedro Mor6n 385, (8520) San Dekinga,A. & Pierstoa,T. 1993. Reconstructingdiet composition Antonio Oeste, Rio Negro, Argentina. on the basisof faecesin a mollusc-eatingwader, the Knot Calid#scanutus. Bird Study40: 144-156. Telephone: + (54)-934-22440 [work]or + (54)-934-22524 [home] Gonzalez,P.M. 1991. Importanciade la Bahia de San Antonioy Facsimile: zona de infiuenciaen el GolfoSan Ma#as para las + (54)-934-21740 (Sr R. Sciu) or comunidadesde aves costeras. Reportof the Legislaturade + (54)-934-22440. la Provinciade Rio Negro,Viedma. Gonzalez,P.M., Pierstoa,T. & Verkuil,Y. 1995. Foodand feeding of Red KnotsCalidris canutus rufa during northward migration in Golfo San Mafias, Argentina. Submittedto J. Field Ornithol.

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