Nlkolaev:Importance of UpperVolga peatland habitats for breedmg waders The importanceof the peatlandsof the Upper Volga area as habitats for breeding waders V.L Nikolaev Nikolaev,V.I. 1998.The importance of thepeatlands of theUpper Volga area as habitats for breedingwaders. InternationalWader Studies 10: 291-298. In theTver region 31 wader species were recorded and of these,19 species breed there, 11 species areconsidered rare and ten of theserare species breed in differentpeatlands. Golden Plover Pluvialisapricaria and Whimbrel Numenius phaeopus breed only on raised bogs, Marsh Sandpiper Tringastagnatilis and Great Snipe Gallinago media breed only on fens. Ruff Philomachus pugnax, RedshankTringa totanus, Black-tailed Godwit Limosa limosa and Curlew Numenius arquata are widelydistributed on peat-bogs and have their maximum density on fens. Single breeding records ofJack Snipe Lymnocryptes minima are known for eutrophicand mesotrophic bogs. In thelast decadeTerek Sandpipers Xenus cinereus have started to breed on transformed peatlands. Wader speciescomposition and abundance vary considerably among peatlands of differenttypes due to differencesin theirsize, forest-cover and the presence of openwater areas. The large raised bogs, withcomplex habitats from marginal eutrophic parts to centralareas with peat-ridges and open waterareas, have the highest number of rarebreeding wader species (up to seven),although their densityis ratherlow (2.1+0.3pairs kin-2). The mostmarked fluctuations in numbersare found on smallbogs and in dryyears some species do not breed there at all. Eggand chick predation is higheron longnarrow bogs than on roundedones of the samearea. In recentdecades the increase in HoodedCrow Corvus cornix numbers at thebogs has negatively influenced the breeding success ofwader species. Overall, 160 bogs in theregion were excluded from drainage and peat-industry plansin the1980s and all forest-cuttingis planned to stopby 1993.With the development of anthropogenicactivities in theregion, the relative value of peatlandsas a habitatfor rarewader specieswill probablyincrease in the nearfuture. V.I.Nikolaev, Zavidovo State Game Reserve, Konakovo district, Tver' region, 171274, Russia. Hu•oaaeB,B. 14. tOOS. 3.a,•eaue Top•saU•oB Bepxaero Hpusoa•,as •a• •ecToo6uTaHus InternationalWader Studies 10: 291-298. B Tnepc•o•o6aacT• 6•aa aaper•cTp•po•aH 5t • •ya•o•, •s •OTOp• i9 B•OBrHea•aTCa, tt Cq•Ta•TCapea•, c•a• •a•x •ao• tO raesaaTCa• pasa•qa•x TO•Sa•ax. 3oaor•cTas pma•KaPluvialis ap•ca•a u c•aaua K•amaen Nu•nius p•eo•s raesbsrcs .a sepxosb•x•aorax, nopyqeaau•Tnnga stag•alts • ayneab•11inago media •Ta•T TOab•o .a .uasaam •aorax.TypyxraaPhilo.&us pugs, rpasas• T•nga totanus, se•eaas• Ltmosalimosa • •abmo• •.mae. Numeniusarquata munro pacn•rpaae• TO•H•ax, Aocr•raaMaRc•MaAbHO• HAOTH•TH Ha HH3HHHb• •AoTax. •sBecTHb] e•uauqabIecayqau raeaaoMaus rapmaena Lymnoc•ptes mimmus .a enr•a• •eaot•abm •aotax. H•aeaaeea•stsaetse .a np•6paaonaaabixTop•sau•ax .aqaaa raeaguTbCflMo•yaRa Xe•s cinereus.8u•oBofi •TaB • q•caeHH•TbRya•ROB 3Haq•TeabBO MeBfl•TCflB •BHCHM•THOT paaabm THHOB TO•flHH•OB H3-3fl paaauqufi B ux nao•aAu, noR• • .aauquuOTRpb•b• BOy.MOB. Ha Rpynnbmnepxonbm •aoTax co 6uotona•u,ot entp•ab•x yqacTRos.a •pa• ao •eaTpaab• qacTefic Top,sarMa UOTRp•b•U •a•a•, o6utaeT•abmuacTno •g•ux Ryau•on(go cema nugon), XOTa naOTaO•bUXraeaao•aass aosoa•.o .sa•a (•,t•,5 nap/R•.Ca•Ie aa•eTabie qHcAeBH•THOTMeqa•TCfl Ha H•abmHX •aOTaX,rae s cyxueroab• .e•oropble suAb• so•e qeM.a oKpyras•ro• menao•aas. • n•aeaase •aT•aeT• •s•aa q•caeaH•Tbce• BO•H• CO•S CO• HTOorpu•areabaO HOBAHHAO Haycnex raeaao•.ss paaam BH•OB •yau•on.B qeao•,s 1980-xroaax 1• &aor n •rsoae 6•a..c•a•qeab• usnaaaon gas •ymeaus•a• u ro•saonsa paspa•ro•,s • 1•3 roay•naaau•.o n•pa•eaue Bmpy• A•OB.Hpu pa3B•t• B •ruoae aax•norea.o• geflTeabaocT•Bnoaae BO3MOm. O,HTO BH•OB •ya•OS 291 International Wader Studies 10. 291-298 Introduction visitingsome of the largepeat-bogs. About 500 questionnairesabout the birdswere circulated,and Waders,being one of the mostdiverse groups of informationfrom these and personal non-passerinebirds on peatlands,play an important communicationswith localinhabitants and game- rolein the functioningof peat-bogecosystems. The managers(more than 1,000people) were alsoused. importanceof peat-bogsas wader habitats is Routeswere planned taking into accountthe determinedby their environmentalcharacteristics, circularstructure of a peat-bogfrom its peripheryto their vulnerabilityto humanactivities, and the the centre(edge zone, strips of sparselow trees, acceleratedrates of reductionof the virginpeat-bog openareas, pool-ridge complexes etc.) thus making areasin manyparts of EuropeanRussia. it easierto locatesites which were usedby waders. Conservationof peat-bogsin economicallywell- On very largepeat-bogs several survey routes were developedregions is oneof the mostpromising used,crossing the widest parts with stopsin the waysof protectingrare waders and maintaining "forest-islands"within the bog. speciesdiversity. The mainbulk of the surveyswere conductedin the The mainobjective of thisstudy was to evaluatethe breedingperiod during May to June,as later,there presentstatus and main trendsin wader was a ratherrapid departureof wadersto populationson the peat-bogsof the upperVolga neighbouringwater bodies and uplands.Visits river areawhich are affectedby humanactivities, were madein themorning, from sunriseuntil 10 or and analysethe role of peat-bogsfor the 11 am and in the evenings.Censuses were conservationof this groupof birds. Special conductedeither on a repeatedor on a singleroute attentionwas paid to collectingdata on distribution, numbers,population densities and habitat during the breedingperiod; all birdswere counted, regardlessof theirdistance from the observer.Each characteristicson the differenttypes of virginand censusroute was 10 to 15 km long, and their total transformedpeat-bogs of the studyregion. lengthwas 270km. Densitieswere estimatedlater, usingthe separate-groupmethod with calculations Study Area and Methods accordingto averageobservation distances (Ravkin The studies were conducted from 1980-1991 in the 1967). Densitieswere not estimatedfor the rarest upperVolga river area,mostly in Tver'region waderspecies. Abundance values were calculated (formerlyKalinin region) and partly in the in accordance with the area of defined habitats. In neighbouringareas of Novgorod,Pskov, Smolensk localareas with very high wader densities(pond- and Vologdaadministrative regions. Seventy peat- ridge andpool-ridge complexes), a nestmapping bogs,occupying a totalof about270,000 ha (45%of methodwas used, together with registrationsof the totalpeat-bog area in the region)were surveyed alarmingbirds (Durcz & Tomialojc1974; Svensson duringthe studies,67% of whichwere oligotrophic 1978). raisedbogs), 23% were eutrophicfens (eutrophic swamps),and 10%were mesotrophic bogs. The Results and Discussion vastraised bogs with ponds,pools and ridges Differentwader species use peat-bogs in different (coveringabout 1000 ha), whichsupport the most ways:from rarevisits during migration,to regular diversewader fauna,due to their complicated structure, amount of water and absence of forests, breedingwithin thebogs. In the upperVolga area 31 wader specieshave been recorded, 18 of which were exploredthe mostcarefully. When selecting are moreor lessconnected with differenttypes of thepeat-bogs to be surveyed,we basedour virgin and/ortransformed peat-bogs, and 14 of selectionon data from a specialregional list of peat- whichbreed there (Table 1). Besidesthe species bogscompiled by the Ministryof Geologyfor the mentionedin Table1, JackSnipe Lymnocryptes peatindustry which contained the mostcomplete minimaalso probably breed in the peat-bogsof the dataon typology, size, vegetation and the level of region. economicdevelopment for eachof thesepeat-bogs. No othermarshy habitats were exploredduring the presentstudy. Oligotrophicraised bogs Thistype of peat-bogprevails in the studyarea, In total, about 3,000 km were covered on foot and bothin the totalarea (67% of all peat-bogs)and in 200km wereexplored by boat. The mostdetailed the sizeof individualbogs (on average580 ha). studieswere conductedon the bogsof the south- Almostall thebreeding areas of GoldenPlover westernand westernparts of the upperVolga area Pluvialisapricaria and WhimbrelNumenius phaeopus (Valdayupland), and in the areasof the Upper were locatedon the openbogs with pool-ridge Mologariver and the Volga-Shoshalowland. In complexeson theValday upland of the western otherareas, only certainselected peatlands were upperVolga area, which adjoins the breedingareas visited. of thesespecies in the Pskovand Novgorodregions, as well asin northernBelarus (Malchevsky & While planningthe surveyroutes, we analysed Pukinsky1983; Kozlov & Kuzmenko1989; 1:100,000scale topographic maps, plans of the peat- Mischenkoet al. 1991). The distribution and lands,and aerialphotos. Aerial observations from numbersof thesespecies are not stablebecause the smallplanes and helicopterswere madebefore studyarea is at the limitsof theirbreeding range: during the lastcentury they underwenta local 292 Nflcolaev:Importance of Upper Volgapeatland habitats for breedingwaders Table1. Waderspecies composition in the upperVolga peatlands. Species Raisedbogs: Mesotrophicbogs Eutrophicfens transformed peat bogs Pluvialisapricaria Charadrius dubius Vanellusvanellus Tringaochropus Tringaglareola Tringanebularia Tringatotanus Tringaerythropus Tringastagnatilis Actitishypoleucos Xenuscinereus