Breeding birds in the Macedonian Pine Pinus peuce forests:species composition and status in the Pirin National Park, BulgariaPtice gnezdarice šuma molike Pinus peuce: sastav vrsta i status u Nacionalnom parku „Pirin” (Bugarska)

Nikolov, S.

Istra|ivanje sastava vrsta i njihovog statusa u šumama molike Pinus peuce je realizovanotokom 2004. i 2005. u Nacionalnom parku Pirin (JZ Bugarska). Prikazana je verovatnostnjihovog gne|�enja, migratorni i status u pogledu zaštite, zoogeografske osobenosti, podelavrsta prema mestima na kojima se gnezde i visinsko rasprostranjenje. Vrednost staništa upogledu zaštite je diskutovana sa ornitološke ta�ke gledišta.Key words: breeding birds, species composition, conservation status, Macedonian Pine, Pinuspeuce, Pirin National Park, Bulgaria

INTRODUCTION

It is fairly evident that habitat is likely to be an important determinant of the distribution ofbirds (Bibby et al., 1998). Obtaining information on bird species composition in a particular habi-tat is needed to predict bird associations in poorly explored regions as well as to evaluate the con-servation status of this habitat. Such an approach is needed to identify habitats and sites requiringspecial protection, research targets, and management strategies (Scott et al., 1986). Forest birdshave been at the center of concern over environmental impacts in the last few decades (Avery &Leslie, 1990) because they have often been suggested as indicators or monitors of healthy forestecosystems (Furness & Greenwood, 1993). However, the majority of studies on birds of conifer-ous forest in Europe were carried out in second-growth plantations or in plantations of introducedtree species (e.g. Patterson et al., 1995; Gjerde & S�tersdal, 1997; Díaz et al., 1998; Mörtberg,2001; Sjöberg & Danell, 2001), whereas natural and primeval forests are comparatively poorlystudied (Szaro & Balda, 1979; Haila & Järvinen, 1990; Edenius & Elmberg, 1996;Wesolowski, 2003). Data about these habitats are needed especially for those of them that are ofglobal importance, such as Macedonian Pine Pinus peuce forests.

Macedonian Pine forests are endemic in several mountains of the Balkan Peninsula (Tutin etal., 1993) and Macedonian Pine is included in the IUCN Red List of Threatened species (2004).The majority of such forests are old and almost intact. Despite the high conservation value of thishabitat, little is known about the current status of birds breeding there. Up to now, three papersconcerning birds in Macedonian Pine forests have been published in Bulgaria (Simeonov, 1975;Spiridonov, 1987; Sichanov, 2002). Fragmentary data are also available in some other papers(Simeonov, 1986; Hagemeijer & Blair, 1997; Shurulinkov et al., 2003; Popov et al., 2005),but they are not exhaustive enough to fully represent this avian community.

This paper provides recent data on breeding bird species composition and conservation statusin Macedonian Pine forests with the aim to broaden the knowledge about this threatened, but poor-ly studied habitat. The conservation status of breeding birds is discussed to clarify the conserva-tional value of Macedonian Pine forests from the ornithological viewpoint.

STUDY AREA DESCRIPTION

The Macedonian Pine is a Tertiary relict belonging to primeval quasi-boreal mesophyte vegeta-tion, distributed endemically in Serbia, Montenegro, Macedonia, Albania, Greece and Bulgaria

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(Tutin et al., 1993). It can be found in Bulgaria mainly in mountains in Pirin, Rila and Slavjankaand partly in Stara Planina, Vitosha and Western Rodopes. In Bulgaria such forests cover a totalarea of 12000 ha (Iordanov, 1963; Bondev, 1991). Normally Macedonian Pine grows between1700 and 2000 m elevation (1200–2200 m a.s.l.) where there are rocky acid soils on silicate ground(Iordanov, 1963; Bondev, 1991). The pines reach a height of about 30 m forming comparativelyopen forests with a characteristic ground cover of Whortleberry Vaccinium myrtillus andSmallreed Calamgrostis arundinacea. Communities with some arcto-alpine vegetation elementssuch as Siberian Juniper Juniperus sibirica and Mountain Dwarf Pine P. mugo occur at the lowerlimit of the sub alpine zone (Bondev, 1991; Velchev, 2002).

The survey was carried out in the Pirin National Park (SW Bulgaria) which is recognized as aUNESCO World Heritage Site and an Important Bird Area (Kostadinova, unpubl.). It holds 42% of

Faunistika – studije 27

Figure 1. Location of the Pirin National park in Bulgaria and localities of studied areas within thepark: (1) Bela Reka valley; (2) Bunderishka River valley; (3) area of Shiligarnika; (4)

Demjanishka River valley; (5) Bezbojka River valley; (6) Demirkapyiska River valley; (7)Bashmandrevska River valley; (8) Kelyova River valley; and (9) Sinanishka River valley

Slika 1. Polo|aj Nacionalnog Parka Pirin u Bugarskoj i istra|ivanih lokaliteta unutar njega: 1 – dolinaBele Reke; 2 – dolina Bunderiške reke; 3 - podru�je Šiligarnika; 4 – dolina Demjaniške reke; 5 – dolinareke Bezbojke; 6 – dolina Demirkapijske reke; 7 – dolina Bašmandrevske reke; 8 – dolina Keljove reke;

9 - dolina Sinaniške reke

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the national Macedonian Pine population (Petrov, 2003). Forests cover 57.3% of the park surfacewhere Macedonian Pine communities represents 23.4% (5416 ha) and over 95% of them are ofnative origin (Petrov, 2003). The study area has a moderate continental climate and belongs to themountainous climatic sub-region with average annual temperatures of 2–3 °C and an annual ampli-tude of about 17 °C. Winters are cold (mean January temperatures are from –2 to –5 °C) and sum-mers are cool (mean temperatures: 3–5 °C; Koleva, 2003).

METHODS

The field work was carried out during 55 days in June and July (mainly between 6:00 and 12:00 h)and during 13 nights in March and April (between 20:00 and 5:00) in two successive years (2004 and2005). Owls were registered aurally and in some cases they were stimulated by the use of advertising-calls imitation technique (Shurulinkov et al., 2003). The observations were made in homogenousMacedonian Pine forests with different expositions (N, S, W and E), ages (from 60 to above 120 yearsold) and patterns (fragmented and continuous forests; forests edge and interior) between 1700 and2230 m elevation. The field work was concentrated in 9 areas: Bela Reka valley, Bunderishka River val-ley, area of Shiligarnika, Demjanishka River valley, Bezbojka River valley, Demirkapyiska River valley,Bashmandrevska River valley, Kelyova River valley, and Sinanishka River valley (Figure 1).

The breeding evidence was described according to Hagemeijer & Blair (1997). The taxono-mic comments are according to Sibley & Monroe (1990–1993) and groups of birds on the basis oftheir nest sites location follow Cramp (1977–1994). Zoogeographical characteristic of the studiedavifauna was made according to Voous (1960). The breeding avifauna was divided into 3 groups onthe basis of the migration status of species according to Niemi et al. (1998) with some modifications:1) permanent residents – present in studied habitat during the whole year; 2) short-distancemigrants – wintering at lower altitude than the studied habitat is; 3) long-distance migrants – win-tering in southern regions. The conservation status follows BirdLife International (2004). Thehighest altitudinal observation for each species was measured using a GPS unit.

RESULTS

During the present survey 38 bird species were found in the Macedonian Pine forests (Table 1).For 25 of them breeding was confirmed, whilst 8 and 5 species were probable and possible breed-ers respectively in the studied habitat.

Table 1. Bird species found during the breeding seasons in 2004 and 2005 in Macedonian Pine Pinus peuce forests of Pirin National Park,

their breeding evidence, statuses and trends of national populationsTabela 1. Vrste ptica koje su zabele|ene u šumama molike Pinus peuceu Nacionalnom parku „Pirin” tokom gnezdilišnih sezona 2004. i 2005,

verovatnost gne|�enja, statusi i trendovi nacionalnih populacija

28 Ciconia 14.

Conservation statusStatus zaštiteSpecies

Vrsta BE MSSPEC TE TB

The highest altitudinal observation(m a. s. l.)

Nadmorska visina najvišeglokaliteta posmatranja (m)

Buteo buteo PB SDM S S 2100

Accipiter nisus PS SDM S S 2050

Falco tinnunculus PB SDM 3 DCL I > 2230

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Key: BE – breeding evidence: CF – confirmed breeding, PB – probable breeding, PS – possiblebreeding; MS – migratory status: PR – permanent residents, SDM – short-distance migrants, LDM –long-distance migrants; SPEC – species of European conservation concern (BirdLifeInternational, 2004); TE – trend of European populations (BirdLife International, 2004); TB– trend of Bulgarian populations (BirdLife International, 2004)

Legenda: BE: – potvrda gne|�enja: CF – potvr�eno gne|�enje, PPB – verovatno gne|�enje, PS– mogu�e gne|�enje; MS – migratorni status: PR – stanarice, SDM – selice na kratke razdaljine,LDM – selice na duge razdaljine; SPEC – vrste od evropskog interesa za zaštitu (BirdlifeInternational, 2004); TE – trend evropskih populacija (BirdLife International, 2004); TB –trend populacija u Bugarskoj (BirdLife International, 2004)

Faunistika – studije 29

Tetrao urogallus PB PR S D 2155

Columba palumbus PB SDM 4 S S 2090

Strix aluco PB PR 4 S S 1930

Aegolius funereus PB PR (S) S 1910

Dryocopus martius CF PR S I 2130

Dendrocopos major CF PR S S 2160

Anthus trivialis CF LDM S S 2190

Motacilla cinerea CF SDM S S > 2230

Cinclus cinclus CF SDM S S 1900

Troglodytes troglodytes CF SDM S S 2190

Prunella modularis CF SDM 4 S S > 2230

Erithacus rubecula CF PR 4 S S 2190

Phoenicurus ochruros CF LDM S S > 2230

Ph. phoenicurus PS LDM 2 (DEP) (S) 1930

Turdus viscivorus CF SDM 4 S S 2175

T. torquatus CF PR 4 S S > 2230

Sylvia atricapilla PS LDM 4 S S 2030

Phylloscopus collybita CF LDM S S > 2230

Regulus regulus CF PR 4 S S 2220

R. ignicapillus PS PR 4 (S) S 2090

Parus montanus CF PR S S 2230

P. major CF PR S S 2170

P. ater CF PR (S) S 2220

P. cristatus CF PR 2 (DCL) S 2220

Sitta europaea CF PR S S 2180

Certhia familiaris CF PR S S 2220

Nucifraga caryocatactes CF PR S S 2220

Fringilla coelebs CF PR 4 S S 2200

Serinus serinus CF LDM 4 S I 2160

Carduelis chloris PB SDM 4 S S 2025

C. carduelis PB SDM S S 2025

C. spinus CF SDM 4 S S 2170

Loxia curvirostra CF PR (S) F 2220

Pyrrhula pyrrhula CF PR (S) S 2220

Emberiza cia PS SDM 3 (DEP) S 2035

Conservation statusStatus zaštiteSpecies

Vrsta BE MSSPEC TE TB

The highest altitudinal observation(m a. s. l.)

Nadmorska visina najvišeglokaliteta posmatranja (m)

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Half of the studied breeding avifauna consisted of permanent residents followed by short-dis-tance migrants; the long-distance migrants are in a minority (Figure 2). The majority of specieswere nesting in trees and shrubs, 32% of these being hollow-nesters. Ground nesting bird specieswere fourfold fewer and the minority was species nesting on rocks (Figure 3). CategoryNonpasseriformes was represented by 9 species (24%), while Passeriformes was represented by29 species (76%).

Figure 2. Migration status of breeding birds in Macedonian Pine forests of the Pirin National ParkSlika 2. Migratorni status vrsta koje se gnezde u šumama molike u Nacionalnom parku „Pirin”

Figure 3. Nest site selection of breeding birds in Macedonian Pine forestsof the Pirin National Park, south-western Bulgaria

Slika 3. Izbor mesta za gne|�enje vrsta pticakoje se gnezde u šumama molike u Nacionalnom parku „Pirin”

The majority of observed species belongs to the Palearctic zoogeographical category, followedby Holarctic, European and Turano – European zoogeographical categories (Figure 4).

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Figure 4. Zoogeographical characteristic of breeding avifauna in Macedonian Pine forests of thePirin National Park

Figure 4. Zoogeografske osobenosti gnedilišne avifaune šuma molike u Nacionalnom parku „Pirin”

DISCUSSION AND CONCLUSIONS

Twelve species previously unrecorded in the Macedonian Pine forests were confirmed duringthe present survey. These were: Common Buzzard B. buteo, European Sparrowhawk A. nisus,Common Kestrel F. tinnunculus, Tawny Owl S. aluco, White-throated Dipper C. cinclus, BlackRedstart P. ochruros, Common Redstart P. phoenicurus, Blackcap S. atricapilla, Great Tit P.major, European Greenfinch C. chloris, European Goldfinch C. carduelis, and Rock Bunting E. cia.These comprise 48 % of the avian species in the studied habitat. Of all the species found during thepresent study, three are not typical forest birds. White-throated Dipper and Gray Wagtail M.cinerea are not associated directly with Macedonian Pine forests but with rivers and streams(Cramp, 1977–1993) running through the forests.

During this study 4 species (Eurasian three-toed Woodpecker Picoides tridactylus, Song ThrushTurdus philomelos, Eurasian Jay Garrulus glandarius and Eurasian Linnet Carduelis cannabina)previously observed in Macedonian Pine forests (Simeonov, 1975; Sichanov, 2002) were notfound there.Eurasian Linnet is a typical species of open land (Hagemeijer & Blair, 1997) andmost likely the observation in the studied forest habitat is casual. Jay normally inhabits a lower ele-vation than is optimal for Macedonian Pine forest and it was observed by Simeonov (1975) pro-bably because his study was carried out between 1500–1650 m a. s. l. close to the lowest limit ofMacedonian Pine forests’ elevation range. At this elevation Macedonian Pine forests are mixed withother tree species (Penev & Georgiev, 1958) such as Norway Spruce Picea abies and Scots PinePinus sylvestris where Jay could be found (Nankinov, 1997; Sichanov, 2002). As the Eurasianthree-toed Woodpecker in Europe normally inhabits subalpine coniferous forests (often domina-ted by old spruce, to the exclusion of pure Scots pine or Arolla pine Pinus cembra) on steep inac-cessible slopes (Cramp, 1977–1993) up to 2300 m a.s.l. (Glutz & Bauer, 1980), Macedonian Pineforests seem to be suitable habitat for this species. Although the subspecies alpinus is more restric-ted to spruce forests (Hagemeijer & Blair, 1997) at 1400–1500 m a. s. l. elevation (Hess, 1983)it is very likely that it was not found during the present study because of its rarity. In some areas

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Song Thrush ascends to the tree line (1600–2200 m a.s.l.) in coniferous forest and the absence ofthis species during this study is probably due to the lack of ample undergrowth that it requires(Cramp, 1977–1993). The results of the present survey could not be compared with these of thesurvey of Spiridonov (1987) because the latter was carried out not in homogenous but in mixedMacedonian Pine forest.

There is an obvious difference between avian communities in studied quasi-boreal MacedonianPine forests and real boreal forests. It is fairly well known that the proportion of migratory speciesin boreal forest bird communities varies considerably, depending on latitude and habitat type(Niemi et al., 1998). However the number of migratory species generally exceeds the number ofpermanent residents that sometimes represent only 5-15% of the local breeding avifauna (Helle &Niemi, 1996; Niemi et al., 1998) whereas in the studied habitat resident breeders predominated.The number of long-distance migrant species normally is above 30% in both Palearctic and Nearcticboreal forest bird communities (Haila & Järvinen, 1990; Helle & Niemi, 1996) but inMacedonian Pine forests it is twice as low.

From the conservational point of view 45% of the breeding avifauna found during the presentstudy is included in SPEC (Species of European Conservation Concern) categories. Four species(European Sparrowhawk, Western Capercaillie Tetrao urogallus, Tengmalm’s Owl and BlackWoodpecker Dryocopus martius) are listed in the Bulgarian Red Data Book (Botev & Peshev,1985) and 3 species (Western Capercaillie, Tengmalm’s Owl, and Black Woodpecker) are includedin Annex I of the Bird Directive 79/409/EEC. Although the Macedonian Pine forests are among thehabitats with high conservational value in Bulgaria (Kavrukova et al., 2005), the avifauna inhabi-ting them consists of species the majority of which has comparatively low conservation status andstable populations in both Europe and Bulgaria. Despite this, the importance of the avian commu-nity in the Macedonian Pine forest should not be underestimated because this community inhabi-ting primeval forests represents a unique source of information for our better understanding of theecology of forest birds.

SA^ETAK

Ukupno je na istra|ivanom podru�ju zabele|eno 38 vrsta, od kojih 12 nije prethodno regis-trovano u istra|ivanom staništu. Gne|�enje je potvr�eno za 25 vrsta, 8 su verovatne a 5 mogu�egnezdarice. Polovina prou�avane gnezdilišne faune ptica se sastoji od stanarica, za kojimaslede selice na kratke razdaljine, dok su selice na duge razdaljine malobrojne. Ve�ina vrsta segnezdi na drve�u i u |bunju (jedna tre�ina su dupljašice), gnezdarice na tlu su �etiri puta malo-brojnije, a veoma mali broj se gnezdi na stenama. Iako šume molike imaju visok nivo zaštite uBugarskoj, ve�ina ptica koja ih naseljava ima povoljan status zaštite i stabilne populacije uEvropi i Bugarskoj.

ACKNOWLEDGEMENTS

This survey was initiated by the Central Laboratory of General Ecology / Bulgarian Academy ofSciences, financed from the Bulgarian Biodiversity Foundation and supported by the Pirin NationalPark Central Office. I am grateful to the two anonymous referees for their constructive commentsthat improved this paper.

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Author’s address:Stoyan Nikolov

Central Laboratory of General Ecology / BAS, Gagarin 2, Sofia 1113, Bulgarianikolov100yan@abv.bg

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