Pulido et al.: Charadriiformes on the Peruvian coast
Conservation of Charadriiformes on the Peruvian coast
Victor Pulido, Jaime Jahncke, Patricia Makamatsu & Cecilia Flores
Pulldo, V., Jahncke,J., Makamatsu, P. & Flores, C. 1996. Conservation of Charadriiformes on the Peruvian coast. International Wader Studies 8: 55-61.
On the Pacificcoast of Peru, the order Charadriiformesis representedby 75 species,of which 16 are residentand 59 migratefrom the Nearcticand Australregions and the GalapagosIslands. On the basisof studiesdone on shorebirdsbetween 1982 and 1991,suggestions are put forward for modifyingthe criteriafor the establishmentof Hemispheric,International and Regionalreserves within the WesternHemisphere Shorebird Reserve Network alongthe coastsof the southern Pacific.Also proposed is a strategyto be followedfor the conservationof migratorybirds on the coasts of Peru.
En la costadel Pacificoen Peru,el ordende los Charadriiformesesta representado por 75 especies, de lascuales 16 sonresidentes y 59 migrande lasregiones neartica y australy de lasislas Galapagos.En basea estudioshechos sobre aves playeras entre 1982 y 1991,se plantean sugerenciaspara modificarlos criterios para el establecimientode reservashemisfericas, intemacionalesy regionales en el marcode la Redde Reservasde avesPlayeras del hemisferos Occidentala 1olargo de las costasdel oceanoPacifico sur. Tambiense propone una estrategiapara la conservacionde avesmigratorias en las costasde Peru.
Sur la cStepacifique du P•rou, l'ordre desCharadriiformes compte 75 espc•ces,dont 16 y nichentet 59 y migrentdepuis les r•gions n•arctiques et australeset lesties Galapagos. Sur la foi d'•tudes d'oiseauxde rivageeffectu•es entre 1982 et 1991,on proposedes modifications aux crit•res d'•tabllssement,pour lescStes du PacifiqueSud, des r•serves h•misph•riques, intemationales et r•gionalesdu R•seaude r•servespour lesoiseaux de rivagede l'h•misph•reoccidental. On recommandeaussi l'adoption d'une strat•gie de conservationdes oiseaux migrateurs des c•tes du P•rou.
InstitutoNacional de Investigaci6n Agraria y Agroindustrial,Eh'recci6n de Investigaci6n y Vida Silvestre [NationalInstitute for Agriculturaland Agroindustrial Research, Research and Wildlife Division], Apdo. Postal 11-0150 Lima 11, Peru.
Introduction researchwas begun in Paracasand in the Villa beachesand ParaisoLagoon by E. Ortiz and G. Castro,respectively. These studies later extended Until 1980, few studies had been done in Peru on to work on the ecologyand conservationof areas the Charadriiformes that inhabit the Peruvian coast importantto shorebirds(Castro 1984; Castro & (e.g.Hughes 1968, 1970, 1976, 1979; Tovar & Myers 1987;Castro, Myers & Bertochi1988; Castro, Ashmole1970). Only part of studiesconducted by Ortiz & Bertochi 1990). the Peruvian OceanicInstitute (IMARPE) included Charadriiformes. In 1982, the Wildlife Directorate of the formerNational Wildlife Authority (INFOR), In 1985,under a letter of agreementbetween the Canadian Wildlife Service of Environment Canada togetherwith the Pan AmericanShorebird Program, thePhiladelphia Academy of Scienceand other and the former INFOR, a collaborativeprogramme Peruviannon-governmental organizations, was setup to studythe feedinghabits and ecology undertookthe first studieson bird migration. In of the Common Tern Sternahirundo (Pulido 1987). September1982, under the leadershipof J.P.Myers, In February1986, the first aerialcensus of shore- a census of shorebirds was undertaken, and birds was donealong the entirePeruvian coast SanderlingsCalidris alba were banded on the sandy betweenTumbes and Tacna. The resultingdata seashoreof the Mejia resortarea on the southern wereused by R.I.G.Morrison and R.K. Rossin the coastof Peru (Pulido 1983a, 1983b). Atlasof Nearctic shorebirds on the coast of South America(Morrison & Ross1989). In March of the followingyear, censusing and bandingof migratoryshorebirds continued in the In 1987, 1989 and 1991, the Wildlife Research Directorate of the Instituto Nacional de Mejia LagoonsNational BirdSanctuary and in the Paracas National Reserve. In 1983 and 1984, new Investigaci6nAgraria y Agroindustrial(INIAA),
55 International Wader Studies 8:55-61
with the supportof national and international 1989(474), February and March 1990(138 and 312 organizations,organized workshops on research birds,respectively) and March and April 1991(81 and conservation of wild birds, which included and 160,respectively). Overall, 1,560specimens bandingcampaigns in the ParacasNational were banded: 568 SemipalmatedSandpipers Reserve, Nearly 1,600specimens of variousspecies Calidrispusilla, 519 WesternSandpipers Calidris of shorebirdswere banded, Furtherbanding maur/,439 Sanderlings,19 Short-billedDowitchers campaignstook placein Paracasin 1990and 1991, Limnodromusgriseus, 14 SemipalmatedPlovers Charadriussemipalmatus and 1 Black-belliedPlover Field studiesundertaken along the Peruvianand Pluvialissquatarola (Table 3). the entire Pacific and Atlantic coasts have made it possibleto standardizethe bandingof migratory Boththe recaptureand recoveryrates were very shorebirdsusing metal bandsand colouredflags low. For recapturedbirds, the percentagedid not and bands(Myers et al. 1987a,1987b; Pulido 1989) exceed2% of total birdsbanded for that campaign. and to establish avenues for research(Castro 1985; For recoveries,the percentageon one occasionrose Castro& Sallaberry1986). exceptionallyhigh to 12%, pointing to a certain degreeof sitefidelity in migratorybirds wintering This study coverscertain aspects of shorebird in Paracas. migration along the Pacificcoast of Peru, including (1) the resultsof bandingdone over five yearsfrom Important areas for shorebird 1987 to 1991, (2) the identification of those areas conservation in Peru important to the conservationof shorebirdsin Peru and (3) suggestionsfor the establishmentof shorebirdreserves by the WesternHemisphere The Peruviancoast is an arid strip,3,080 km long Shorebird ReserveNetwork (WHSRN). and up to 200 km wide, whichextends along the maritimelittoral betweenBoca Capones in the north and Concordiain the south (Pefiaherrera1989). Its Shorebird migrations along the topographyis varied; it includes53 major rivers, Pacific coast of Peru vastexpanses of coastaldesert, cropland and hill formations. Throughoutis a seriesof wetlands Many migrantshorebirds that stopover on the important to the conservationof Charadriiformes. coastof Peru comefrom the Nearcticregion (Canadaand the United States),the Galapagos Of the mostimportant wetlands along the Peruvian Islands(Ecuador) and the Austral region (South coast,only threeare protected:the National Tumbes Pole and Chile) by horizontalmigration. Others MangroveSwamp Sanctuary (2,972 ha), the Paracas migratevertically when descendingfrom the Andes National Reserve(335,000 ha, of which 217,594ha to the Pacificcoast or the Amazonregion. are marine) and the Mejia LagoonsNational Bird Sanctuary(690.6 ha). Among the unprotected Of the 11 familiesthat makeup the order wetlandsare the Virrihi Estuary,the SanPedro Charadriiformes, 10 occur in Peru (Parker, Parker & mangroveswamps, the Lambayequecoasts and the Plenge1982; Hayman, Marchant& Prater 1986) ParaisoLagoon. Of all theseareas, only the Paracas (Table1). These10 familiescomprise 86 species,of National Reservehas been recognized by the which 75 (87%) inhabit Peru's coastseither WHSRN, designatedas a Regionalreserve in temporarily or permanently. Of the 75 coastal September1991. species,16 speciesare resident,whereas 59 are migratory speciesoriginating from the Nearctic Other wetlandsof nationalimportance on the region (48), the Austral region (6), the Galapagos Peruviancoast include the Ram6n Lagoon,the Islands (1) and the Peruvian Andes (4) (Table 2). mouth of the Chira River, the mouth of the Piura River, the mouth of the Eten River, the Medio Of the 10 familiesthat occurin Peru,Scolopacidae Mundo Lagoons,the Villa SwampsReserve, the is representedby 27 species(all of them Nearctic mouth of the Lurfn River, the PuertoViejo Lagoons, and migratory),followed by Laridaewith 22 species the mouth of the Chincha River, the mouth of the (7 residentand 15 migratory) and Charadriidae PiscoRiver, the Agua SantaLagoons, Punta with 11 species(4 residentand 7 migratory). The 7 Lomitas,Asma, the Tilimaco Lagoons,the Pucchfin remainingfamilies include between 1 and 5 species. Lagoons,the mouth of the CamantiRiver, the mouth of the Tambo River, Punta Coles, the mouth of the LocumbaRiver, the Ite Lagoonsand the Banding of shorebirdsfrom 1987to beachesof Tacna. All thesewetlands of recognized 1991 importanceto migratory birds are interconnectedin variousways by meansof avian migrationroutes. Six banding campaignswere carried out in the The distancesbetween them rangefrom a few kilometres to not more than 100 km. It is therefore ParacasNational Reservein 1987through to 1991. Shorebirds were banded in March 1987 (395), March importantto protectmost of theseaquatic
56 Pulido et al.: Charadriiformes on the Peruvian coast
Table1. SpeciesofCharadriiformes and their status on the Peruvian coast. R = resident,A = Austral(migratory), S= southern,An = Andes(migratory), G = Galapagos(migratory) and N = Nearcftc. Family/Species Commonname Status
Haematopodidae Haematopuspalliatus AmericanOystercatcher R Haematopusater BlackishOystercatcher R
Charadriidae Vanellusresplendens AndeanLapwing An Pluvialissquatarola Black-belliedPlover N Pluvialis dominica Lesser Golden-Plover N Charadriussemipalmatus SemipalmatedPlover N Charadriusalexandrinus SnowyPlover R Charadriusalticola Puna Plover An Charadriuscollaris Collared Plover R Charadriusvociferus Killdeer R Charadriuswilsonia Wilson's Plover N Charadriusmodestus Rufous-chested Dotterel A Oreopholusruficollis Tawny-throatedDotterel R
Scolopacldae Aphrizavirgata Surfbird N Arenariainterpres RuddyTumstone N Tringasolitaria SolitarySandpiper N Tringa]lavipes LesserYellowlegs N Tringamelanoleuca GreaterYellowlegs N Actitismacularia SpottedSandpiper N Heteroscelusincanus WanderingTattler N Catoptrophorussemipalmatus Willet N Calidris canutus Red Knot N Calidrisminutilla LeastSandpiper N Calidrisbairdii Baird'sSandpiper N Calidrisfuscicollis White-rumpedSandpiper N Calidrismelanotos PectoralSandpiper N Calidrispusilia SemipalmatedSandpiper N Calidrismauri WesternSandpiper N Calidrisalba Sanderling N Calidrisalpina Dunlin N Calidrisferruginea CurlewSandpiper N Calidrishimantopus StiltSandpiper N Tringitessubruficollis Buff-breastedSandpiper N Philomachuspugnax Ruff N Bartramia1ongicauda UplandSandpiper N Numeniusphaeopus Whimbrel N Limosahaemastica Hudsonian Godwit N Limosafedoa MarbledGodwit N Limnodromusscolopaceus Long-billedDowitcher N Limnodromusgriseus Short-billedDowitcher N
Recurvirostridae Himantopusmexicanus Black-neckedStilt A Recurvirostraandina Andean Avocet An
Phalaropodidae Phalaropusfulicaria RedPhalarope N Phalaropuslobatus Red-neckedPhalarope N Phalaropustricolor Wilson'sPhalarope N
Stercorarildae Catharactachilensis Chilean Skua A Catharactamaccormicki South Polar Skua A Stercorariuspomarinus PomarineJaeger N Stercorariusparasiticus ParasiticJaeger N Stercorariuslongicaudus Long-tailedJaeger N
Burhlnldae Burhinussuperciliaris PeruvianThick-knee R
Continued
57 International Wader Studies 8:55-61
Table 1. (Cont'd)Species of Charadriiformesand their statuson the Peruviancoast. R = resident,A = Austral (migratory),S = southern,An = Andes(migratory), G = Galapagos(migratory) and N = Nearctic.
Family/Species Commonname Status
Thino•oridae Thinocorusrumicivorus LeastSeedsnipe R
Laridae Larusmodestus Grey Gull A Larus belched Peruvian Tern R Larusdominicanus Kelp Gull R Larusatricilla LaughingGull N Laruscirrocephalus Grey-hoodedGull R Larus serranus Andean Gull An Laruspipixcan Franklin'sGull N Xema sabini Sabine's Gull N Creagrusfurcatus Swallow-tailedGull G Cheidoniasniger BlackTern N Gelochelidon nilotica Gull-bfiled Tern N $terna hirundinacea South American Tern R $terna hirundo Common Tern N $ternaparadisaea Arctic Tern N $terna trudeaui Trudeau's Tern A Sternafuscata SootyTern R $ternaalbifrons LittleTern N $terna lorata Peruvian Tern R $ternamaxima Royal Tern N $ternaelegans ElegantTern N Sterna sandvicensis Sandwich Tern N Larosterna inca Inca Tern R
Rynchopidae Rynchopsniger BlackSkimmer
Table 2. Numbersof residentand migratoryspecies of Charadriiformeson the Peruviancoast. R = resident,A = Austral (migratory),S = southern,An = Andes(migratory), G = Galapagos(migratory) and N = Nearctic(migratory). Family R N A G An Total spedes
Haematopodidae 2 .... 2 Charadriidae 4 4 I - 2 11 Scolopacidae - 27 - - - 27 Recurvirostridae - - 1 - 1 2 Phalaropodidae - 3 - - - 3 Stercorariidae - 3 2 - - 5 Burhinidae 1 .... Thinocoridae 1 .... Laridae 7 11 2 1 1 22 Rynchopidae 1 .... 1 Total species 16 48 6 1 4 75
environmentsusing the legalinstruments available case of areas that do not meet the criteria estab- to the Peruvian government. lishedto date,such as those along the coastof the southern Pacific. Suggestionsfor the establishmentof In principle,the sameparameters should be usedto shorebird reservesas part of the establishHemispheric, International or Regional WHSRN reservesfor the Nearcticregion as for the Neo- tropicalregion. However,the fartheraway Someof the criteriafor establishingInternational, winteringgrounds are located, the fewer species Hemisphericand Regional shorebird reserves and individualsreach them (Rappoleet al. 1953), within the WHSRN may needto be modifiedin the
58 Pulido et al.: Charadriiformes on the Peruvian coast
Table 3. Shorebirds banded in Paracas.
Species Status 87/3 89/3 90/2 90/3 91/3 91/4 Total
Calidris alba 1 118 37 9 66 51 158 439 2 1 0 0 0 0 4 5 3 11 2 0 4 5 12 94 478 Calidris mauri 1 100 216 59 114 30 0 519 2 5 0 0 3 1 0 9 3 5 2 5 9 0 0 21 549 Calidrispusilia 1 165 211 69 123 0 0 568 2 2 0 0 3 0 0 5 3 6 2 5 10 8 9 40 613 Charadriussemipalmatus 1 1 9 0 3 0 1 14 2 0 0 0 0 0 0 0 3 0 1 0 0 0 0 1 15 Liranodromus griseus 1 11 1 1 5 0 1 19 2 0 0 0 1 0 0 1 3 1 0 0 1 0 0 2 22 Pluvialissquatarola 1 0 0 0 1 0 0 1 2 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 1
Total banded 395 474 138 312 81 160 1,,560 Total recaptured 8 0 0 7 1 4 20 Total recovered 23 7 10 24 13 21 98 Total captured 426 481 148 343 95 185 1,678
althoughthey may be essentialhabitats for those numbersof birdsin relationto their reproductive that do. capacity.Furthermore, these populations include juvenilesthat have optednot to migratesouth, In the Nearcticregion, in both pre-breedingand adults that have bred and those birds born in the post-breedingperiods, large numbers of plovers borealsummer of the year. In the south,only part and shorebirdsconcentrate at key sites,such as of the populationthat beganthe post-breeding DelawareBay and the Bayof Fundy on the Atlantic migrationactually reaches the winteringgrounds, coast,San Francisco Bay and the CopperRiver Delta i.e.some of the juveniles,immature birds and on the Pacific coast and Stillwater, Great Salt Lake breedingadults. From this total mustbe subtracted and CheyenneBottoms in continentalareas. the numberof birdsthat die duringthe post- breedingmigration to the wintering groundsand thosethat die at the winteringgrounds from Thereare alsosites with high concentrationsof shorebirds on the coasts of the southern Atlantic: depredationor other climaticfactors or becauseof the destruction of their habitat, which affects birds the large populationsof (1) Semipalmated concentratingin small areasduring migration. Sandpiperon the coastsof Suriname(about 80% of the world population),(2) Wilson'sPhalarope Phalaropustricolor and Red-neckedPhalarope P. Thismeans that the possibilityof a populationof lobatusin the Mar ChiquitaLagoon in Argentina migratorybirds disappearingwith the passageof and (3) Red Knot Calidriscanutus, White-rumped time is greaterat wintering sites. This is fundamen- SandpiperC. fuscicollis and HudsonJanGodwit tally due to the destructionof habitats,which is Limosahaemastica in Tierra del Fuego. Generally occurringmore rapidly every year in South speaking,those species that breedfarther north Americaas a result of anthropogenicactivities. occupyoverwintering areas farther south (Myers et al. 1987a). In contrast, on the Pacific coast, smaller Time is anotherfactor. As the breedingperiod is concentrationsof birdsare dispersedover a wide relativelyshort (from Juneto August),birds are area. forcedto have a greatersense of timing in the north, particularlythose migrating great distances from Anotherfactor is that shorebirdpopulations in the the Arctic (Myerset al. 1987a).This exertspressure Nearcticregion are close to attainingthe optimal on birdsto obtaincertain advantages and to locate
59 International Wader Studies 8:55-61
betternesting sites to ensurebreeding success. The The Mejia Lagoons,for instance,constitute one of resultis a longerwintering period,which also the most importantwetlands of the Pacificcoast of includespre- and post-breedingtravel. Peru. One of the largestSanderling populations is concentrated here. Even so, the number of birds of It is alsolikely that a greaterdestruction of northern this speciesis not sufficientto includethe Mejia areassupporting habitats for thesebirds is causing Lagoonsin any of the WHSRN's categories. a greaterconcentration of birdsin particularly Nonetheless,in this singleprotected area of productivesites. Senner & Howe (1984)showed 690.6ha, 172species have been recorded, or one that birds do not have the option of locatingin speciesfor every4 ha (Pulido1987; Pulido & Myers otherareas given the availabilityof food and 1987). Also, 64 speciesof Charadriiformeswere habitatsprecisely in thosespecific locations. With found on 10 km of beach, or between 6 and 7 regardsto food supply, food is abundantin the speciesper kilometre. north, which makeslarge concentrationsof birds possible,especially at particulartimes, such as at For this reason,the appropriatestrategy for the the end of May in Delaware Bay(Myers 1986). conservationof migratoryshorebirds must Alongthe coastof the southernPacific, on the other necessarilyinclude the establishmentof a seriesof hand, maximum advantageis taken of available protectedareas along the Peruviancoast. First,the food. In the first case,the limiting factoris space, establishmentof suchareas must be approvedand and in the second,it is food. With regardsto supportedby the Peruviangovernment. Second, habitatin the United States,by 1978close to 40%of effortsmust be concentratedon managingthese all aquaticand continentalhabitats had been lost areas. This meansnot only applyingprotective (Horwitz 1978). Althoughno quantitativedata are measuresbut alsodeveloping a plan for the available, the destruction of wetlands in South comprehensivemanagement of wetlands. To this Americahas probably not yet reachedthat extent, end, it is necessaryto considerimportant factors which shouldmake a wider dispersionof birds suchas stagingsites, feeding grounds, variations in possible,as there is morehabitat available. Then water levelsand habitat diversity in such there is the fact that somepopulations spend a managementareas. Only in this way will it be relativelyshort period of time at eachwintering possibleto ensurethe conservationof wetlands site. It is thereforeimportant to conservenot one alongthe Peruviancoast so that shorebirdsfrom locationbut severallocations near eachother along differentlatitudes may find a safeplace to stop the coast, as is the case in coastal Peru. alongthe way in the yearly migrationto their overwintering areas. A differentsurvival strategy is adoptedby birdsin the souththan in the north. While in the north,they Acknowledgements surviveto nest and thus ensurebreeding success; in the south,they survive to recoverfrom thepost- We would like to expressour gratitudeto the breedingmigratory effort and to storesufficient WesternHemisphere Shorebird Reserve Network energyduring the winteringperiod to reinitiatethe for the fundingit providedthe seniorauthor to take returnon pre-breedingflights. part in the Symposiumon ShorebirdEcology and Conservationin the WesternHemisphere, held in Althoughthe criteriafor establishingreserves by conjunctionwith the IV NeotropicalOrnithology the WHSRN are appropriatefor North Americaand Congressin Quito, Ecuador. for the Atlanticcoast of SouthAmerica, they need to be modified for the southern Pacific. The WHSRN, in addition to taking into accountthe References numberof birds in a givenplace, must also stress otheraspects such as speciesdiversity, strategic Castro,G. 1984. Las Aves de la laguna E1Paraiso. [The stagingsites along migration routes, the natural and birds of the El ParaisoLagoon.] El VolanteMigratorio 3: pristinestate of aquaticenvironments and their 10-12. importanceas conservation areas for residentand Castro,G. 1985. M•todo simplepara calcularla autonomiade vuelo en avesmigratorias. [A simple migratory species. methodfor calculatingflight autonomyin migratory birds.] El VolanteMigratorio 5: 22-24. On the Pacific coast of Peru and northern Chile, the Castro,G. & Myers,J.P. 1987.Ecologia y conservaci6ndel presenceof the HumboldtCurrent ensures the playeroblanco (Calidris alba) en el Perti. [Theecology existence of numerous coastal areas with an and conservationof the Sanderling(Calidris alba) in appreciablefood supply. However,basic factors Peru.] Bolefinde Lima 52: 47-61. suchas human intervention and pollutionand the Castro,G. & Sallaberry,M. 1986. E1rol de la investigaci6ncientifica en conservaci6n.[The role of destructionand disappearanceof wetlandscould be scientificresearch in conservation.] El Volante forcingbirds to fly to differentwintering areas. The Migratorio7: 30-32. low recoveryrates of bandedshorebirds would appearto confirmthis.
60 PuBdo et al.: Charadriiformes on the Peruvian coast
Castro,G., Myers,J.P. & Bertochi,L. 1988. Predatoresdel Parker,T., Parker,S. & Plenge,M. 1982. An annotated playeroblanco (Calidris alba) en la costaperuana. checklistof Peruvianbirds. Buteo Books, Vermilh'on, [Predatorsof the Sanderling(Calidris alba) on the SouthDakota. 108pp. Peruvian coast.] Boletinde Lima58: 57-59. Pefiaherrera,C. (ed.). 1989. Atlasdel Peril. [Atlasof Peru.] Castro,G., Ortiz, E. & Bertochi,L. 1990. Importancia InstitutoGeogr&fico Nacional, Lima. 339 pp. biolOgicay conservaci6nde la lagunaEl Paraiso. [The Pulido, V. 1983a. Conclusionessobre experiencias censales en biologicalimportance and conservationof the E1 doslangunas costeras y un Iagoaltoandino. [Conclusions ParaisoLagoon.] Bolefin de Lima 71: 47-55. oncensus-taking experiments in twocoastal lagoons and one Hayman, P., Marchant,J. & Prater,T. 1986. Shorebirds:an highAndean lake.] Unpublished report, Universidad identificationguide to thewaders of theworld. Houghton NacionalAgraria la Molina, Lima. 13 pp. Mifflin Co., Boston,Massachusetts. 422 pp. Pulido, V. 1983b. Evaluaci6nde las Lagunas de Mejœa e Horwitz, E.L. 1978. Our nation'swetlands. Interagency intervenci6nen captura y anillamientodel playero blanco TaskForce Report, US Councilon Environmental (Calidrisalba). [Evaluationof theMej[a Lagoons and Quality, Washington,DC. interventionin thecapture and banding of theSanderling Hughes,R.A. 1968. Noteson the occurrenceof the (Calidrisalba).] Unpublishedreport, Instituto Grey-hoodedGull (Laruscirrocephalus) on the west NacionalForestal y de Fauna,Lima. 10 pp. coast of South America. Ibis 110: 357-358. Pulido, V. 1987. Patronesde variaci6nestacional de las Hughes,R.A. 1970. Noteson the birds of Mollendo poblacionesdeaves en las lagunas de Mej[a. [Patternsof district, southwest Peru. Ibis 112: 229-241. seasonalvariation in birdpopulations in theMejœa Lagoons.] Hughes,R.A. 1976. Additionalrecords of birdsfrom the MSc Thesis,La Molina National Agricultural Mollendo district coast of southwest Peru. Condor University, Lima. 121 pp. 78(1): 118-119. Pulido, V. 1989. Ambientesy avesacu&ticas del Peril. Hughes,R.A. 1979. Noteson Charadriiformeson the [Environmentsand aquaticbirds in Peru.] El Volante south coast of Peru. Stud. Avian Biol. 2: 49-53. Migratorio13: 24-31. Morrison, R.I.G. & Ross,R.K. 1989. Atlasof Nearctic Pulido, V. & Myers,J.P. 1987. Las poblacionesde avesde shorebirdson the coast of SouthAmerica. 2 vols. orilla arenosamarina de Mejla: una propuestapara su CanadianWildlife ServiceSpecial Publication, conservaci6n.[Populations of shorebirdsfrom sandy EnvironmentCanada, Ottawa, Ontario. 325 pp. marine environmentsin Mejla: a conservation Myers,J.P. 1986. Sexand gluttonyon DelawareBay. Nat. proposal.] III Congresode Ornitologia Neotropical [III Hist. 95: 68-77. NeotropicalOrnithology Congress], Cali. 16 pp. Myers, J.P.,Morrison, R.I.G., Antas, P.Z., Harrington, B.A., Rappole,J.M., Morton, E.S.,Lovejoy, T.E. & Ruos,J.L. Lovejoy,T.E., Sallaberry,M., Senner,S.E. & Tarak, A. 1983. Nearcticavian migrants in theNeotropics. US Fish 1987a. Conservationstrategy for migratory species. and Wildlife Service,Washington, DC. 646 pp. Am. Sci. 75: 19-26. Senner, S.E. & Howe, M.A. 1984. Conservation of Myers,J.P., Mclain, P.D., Morrison,R.I.G., Antas,P.Z., Nearcticshorebirds. In: J. Burger& B.L. Olla (eds.), Canevari,P., Harrington,B.A., Lovejoy, T.E., Pulido, Behaviorof marineanimals. Vol. 5. Shorebirds:breeding V., Sallaberry,M. & Senner,S.E. 1987b. The Western behaviorand populations, pp. 379-421. Plenum Press, HemisphereShorebird Reserve Network. WaderStudy New York. GroupBull. 49: 123-124. Tovar, A. & Ashmole,P. 1970. A breedingrecord for the Gray-hoodedGull Laruscirrocephalus on the Peruvian coast. Condor 72: 119-122.
61