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1995. of prey in Japan. Okumura Printing, To- --. 2000. Forest ti-agmentation,competition, and ch- kyo, Japan. matic dependence in the honey buzzard (Pernisap,- ORTA,J. 1994. Western Honey-buzzardand CrestedHon- vorus).J. Ornithol.141:68-76. ey-buzzard.Pages 111-112 in J. del Hoyo, A. Elliott, SUNG,Y.J., W.J. Lo, M. WEI, AND X.L. CHANG.1991. Pre- and J. Sargatal [EDs.], Handbook of the birds of the liminary studyon the breeding biology of the Orien- world. Vol. 2. Lynx Edicions,Barcelona, Spain. tal Honey-buzzard(Pernis ptilorhyncus). Science Print- SAPORETTI,E, W. GUENZANI,AND P. PAVAN.1994. Density, ing, Beijing, China. ,and breedingsuccess of diurnal raptorsin the VAN MANEN, W. 2000. Reproductive strategy of honey Prealpsof NW Italy.Riv. Ital. Ornitol.63:145-173. buzzardsPernis apivorus in the northern Netherlands. SELAS,V. 1997. Nest-siteselection by four syrupatticfbrest Limosa 73:81-86. raptorsin southernNorway. J. RaptorRes. 31:16-25. STEINER,H. 1992. The diurnal raptor community of a farmland area in upper Austria. Egretta35:96-110. Received 5 January 2004; accepted 3 September 2004

j RaptorRes. 38(4):371-374 ¸ 2004 The Raptor ResearchFoundation, Inc.

WINTER DIET OF THE GREATERSPOTTED (AQUILACLANGA) IN THE AMVRAKIKOS WETLANDS, GREECE

HARALAMBOS ALIVIZATOS 1 4 Zaliki Str., GR-115 24 Athens, Greece

DIMITRIS PAPANDROPOULOS 21 Zaimi Str., GR-26 500 Rion, Greece

STAMATIS ZOGARIS NationalCenter for MarineResearch, Institute of Inland Waters,P O. Box 712, 19 013 AnavyssosAttiki, Greece

KEYWORDS: GreaterSpotted Eagle,, ;diet;, win- international cooperation, monitoring, and research ter, wetland;Amvrakikos; ¸reece. (Meyburg et al. 2001). The biology of the Greater Spot- ted Eagle has not been examined to a great extent; ad- The Greater SpottedEagle (Aquilaclanga) is a globally- ditionally, its diet has been examined almost exclusively threatened raptor, which breeds from Eastern to during the breeding season(e.g., Priklonsky 1960, Gal- the Pacific coast of the northern Far East and winters ushin 1962, Pankin 1972, Ivanovsky1996). Few studiesof locally in southern Europe, Asia, the , and any kind have been conducted in the winter quartersof sub-SaharanAfrica as thr south as Uganda and Kenya this (Moltoni 1943,Francois 1992, Qingxia 1996) (Tucker and Heath 1994). The main reasonstbr its de- Although an important population of Greater Spotted cline are habitat destruction and degradation (in both Eagleswinters in the extensivewetlands of northern and forests,where the speciesnests, and wetlands,where it central Greece (45-85 individuals), up to now it has re- forages),disturbance during the breedingseason, illegal ceived very little attention (Hallmann 1989, Handrinos shooting (mainly in migration), and to a lesserextent, and Akriotis 1997). Here, we present the results of an nest robbing (Tucker and Heath 1994, Meyburg et al. examination of Greater Spotted Eaglesat a key wintering 2001). The primary proposed conservationmeasures in- site, the Amvrakikos wetlands, western Greece, where up clude the establishmentof protected areasin the breed- to 12 individualswinter each year. mg habitat of the species,preservation of a mosaic of STUDY AREA AND METHODS breeding-feedinghabitat, protection of wetlands,avoid- ance of disturbanceduring the breeding seasonwithin Our studyarea was in the Amvrakikoswetlands, west- 300 m of nests, as well as improvement of legislation, ern Greece (38ø59'-39ø11'N, 20ø44'-21ø07'E). Amvrak•- kos is a Ramsar Wetland, a Special Protection Area, and proposedNational Park. It is one of the largestwetlands E-mail address:[email protected] in Greececovering 220 kma includingriver deltas,coastal 372 SHO1•TCOMMUNICATIONS VOL. 38, No. 4

lagoons, extensive saltmarshes,reedbeds, relic riparian as Common Moorhens (Gallinula chloropus),Common woods, and grazed grasslands.Large areas bordering the Coots (Fulica atra), Little Egrets (Egrettagarzetta), and salt marsheshave been drained and support intensiveag- small gulls (Larus spp). We alsofound lead shot in 3.2% riculture and livestockfarming. The roost site of the of the pellets. Greater Spotted observed was located in a small clump of very tall Eucalyptustrees on the banks of the DISCUSSION Arachthos River, <2 km awayfrom a major village. This roost is ca. 2 km from the estuarine wetlands of the river Although the samplewas comparatively small, some in- delta and is in a region of intensive agriculture, domi- terestingconclusions may be drawn. The proportion of nated by citrus plantations.The scatteredtrees along the birds found in the diet was higher in the Amvrakikos bank of this region of the river include white poplar (P0- wetlandsthan in any other studyof the Greater Spotted pulus alba), willows (Salix sp), ashes (Fraxinussp.), and Eagle. Priklonsky (1960), in the mouth of the BelayaRiv- common alder (Alnusglutinosa). Anfid the nativeriparian er, Russia,based on pellet analysis(78 pellets and 274 trees are a few planted eucalyptus(Eucalyptus sp.), some reaching a considerableheight (ca. 40 m). In the winter prey items) reported the diet of the species,consisting of 2001-02, eagles roosted exclusivelyon the Eucalyptus of 69.0% mantotals,23.0% reptiles,7.7% birds,and 0.3% sp, but they did not seemto use thesetrees in the winter fish (only vertebrates included). In addition, insectsoc- of 2002-03, althoughthey did gather to roost in the tree curred in 29.4% of the pelletsand carrion (primarily standsin the vicinity.In other parts of Amvrakikos,eagles moose[Alces alces] ) in at least20.5% of the pellets.Study roost on oaks (Quercusspp.) in the ad.jacent limestone of the prey remains in the nests of the eaglesalso re- hfils (100-300 m elevation) 1-5 km awayfrom the wet- vealed a predominance of and birds. Most land . We located four such roosts in the Am- mammals were small rodents, while most reptiles were vrakikos, but pellets where collected only from the one at the Arachthos Delta because the others were in rela- snakes.Priklonsky (1960) summarized the resultsof sev- eral studies as follows: n•ammals 66.0-88.6%, birds 46.2- tively inaccessibleareas (steep, forested hills), or difficult to pin-point with precision (woodlotsin marshes). 97.0%, insects5.5-34.0%, and reptiles0.0-12.3% (occur- The diet of the specieswas studied by the analysisof rence in pellets). Galushin (1962) in the valley of the pellets that were collected in January and March 2002 Oka River during the period 1954-57, found the follow- from under the regular roost,in a smallEucalyptus clump, ing yearly variation in diet: n•ammals42.6-68.0%, birds which was used by six to seven Greater Spotted Eagles. 32.0-69.0%, fish 0.0-1.8%, and reptilesand amphibians Up to two Common Buzzards (Buteobuteo) were also seen each 0.0-0.6% (basedon prey numbers).In Byelorussia, to use the trees near the Eucalyptustrees, but not near Ivanovsky (1996) found that 50 prey items (from re- the eagles.Buzzard pelletswere easilydistinguished from mains)were 53.8% mammals,21.1% amphibians,17.4% those of the eagles by a combination of both size and birds,and 7.7% reptiles.Qingxia (1996) studiedthe diet form (eagle pellets were ca. 70-120 X 30-50 mm and had a generally loose form, while those of buzzardswere of the eagles wintering in the Lishan Nature Reserve ca 50-75 X 20-35 mm and were quite compact). Be- (China) and found the diet consistedof about equal cause of these differences and in combination with their numbersof mammalsand birds (N = 68 prey items). The location, we f•el that it is unlikely that pellets of the two mammals consumed were mostly rodents, as well as some specieswere confused.Prey remains were identified with rabbits,collectively making up 52.1% of the diet by biD- the help of reference books (Brown et al. 1987, Chinery mass.A varietyof specieswere alsoeaten (47.9% of 1993, Macdonald and Barrett 1993). The number of prey diet by biomass),including severalgamebirds (Phasiani- •tems was determined by counting the number of skull dae). and major limb bones represented, when these were Often, the study of pcllets can result in biased esti- present; unless these indicated otherwise, we assumed mates of diet composition; that is, this methodologycan the presenceof one individual of each prey type per pel- let lead to the underestimateof certain prey types (particu- larly amphibians)and the overestimatein others.Vlachos RESULTS and Papageorgiou(1996) found that a large proportion of the prey delivered in the nestsof LesserSpotted Eagles We collected57 pelletsfrom the Eucalyptusroost, used (Aquilapomarina), as recorded by direct observation,con- by 6-7 individuals.The size of the pellets was ca. 70-120 sistedof frogs, but these were only infrequentlyrepre- X 30-50 ram. In the studyarea, the Greater Spotted Ea- sented in the pellet analysis.Also many, or all, of the gle preyed primarily on birds, but it also took mammals, insectsfound in pellets in this and other studies,may reptiles, amphibians,fish, and insects(Table l). By num- have been ingested secondarily (i.e., consumedby the bers, among95 prey items,birds comprised84.2% of the eagle prey). diet, followed by insects,mammals, reptiles, fish and am- Nearly all the prey speciesidentified inhabitedwetland phibians (Table 1). By mass,birds were even more im- habitats,particularly the salt marshesand coastallagoons portant (94.6%), while other prey were of comparatively (Table 1). Surprisingly,few speciesof prey from the ad- minor importance. The most important birds, in terms jacent agricultural lands were taken (e.g., the small ro- of biomass,were ducks, particularly Eurasian Wigeons dents and beetles). (Anaspenelope) and Common Teals (Anas crecca),as well The high proportion of water birds in our study was DECEMBER2004 SHORT COMMUNICATIONS 373

Table1. Diet of the GreaterSpotted Eagle (Aquila clanga) in the AmvrakikosWetland (N = 57 pellets).

PERCENT PERCENT COMMON NAME SCIENTIFIC NAME NUMBER NUMBER BIOMASS

Insects Insecta 5 5.3 < 0.1 Ground beetles Carabidae 5 5.3 <0.1

Fish Pisces 2 2.1 3.1 Mullets Mugilidae 2 2.1 3.1 Amphibians Amphibia 1 1.1 0.1 Frogs Ranasp. 1 1.1 0.1 Reptiles Reptilia 3 3.2 0.5 Snakes Colubridae 3 3.2 0.5

Birds Aves 80 84.2 94.6 LittleEgret Egrettagarzetta 3 3.2 4.7 EurasianWigeon Anaspenelope 11 11.6 27.4 Common Teal Anas crecca 17 17.9 15.9 Unidentifiedducks Anasspp. 5 5.3 7.8 SpottedCrake Porzanaporzana 1 1.1 0.3 WaterRail Rallusaquaticus 2 2.1 0.7 Common Moorhen Gallinulachloropus 16 16.8 14.9 Common Coot Fulica atra 4 4.2 8.7 Unidentified rails Rallidae 1 1.1 0.3 NorthernLapwing Vanellusvanellus 1 1.1 0.6 CommonRedshank Tringatotanus 1 1.1 0.4 CommonSnipe Gallinagogallinago 1 1.1 0.3 Unidentifiedscolopacids Scolopacidae 1 1.1 0.3 Yellow-leggedGull Laruscachinnans 1 1.1 3.7 Unidentifiedsmall gulls Larusspp. 5 5.3 4.7 Hooded Crow Corvus corone 1 1.1 1.6 ReedBunting Embe•zaschoeniclus 3 3.2 0.3 Unidentifiedpasserines Passeriformes 4 4.2 0.4 Unidentified birds Aves 4 4.2 1.9 Mammals Mammalia 4 4.2 1.7 EasternHedgehog Erinaceusconcolor 1 1.1 1.6 Unidentifiedvoles Microtussp. 1 1.1 0.1 Unidentified mice Mus spp. 2 2.1 0.1 Total -- 95 -- --

probablydue to their high availabilityin the area, com- where manywater birds are present.These areas,as well pared with other potentialprey during the studyperiod. as providing relativelyabundant prey, alsoprovide cover The winter of 2001-02 was relatively "severe"with peri- suitablefor the eaglesto surprisetheir prey. Wc made ods of frosts,thus reptiles and amphibianswould hardly relativelyfew observationsof the eaglesover large open have been available to the eagles (in fact, the presence lagoonsor the surrounding sandy spits, in which the of reptiles and amphibians,even in low numbers, was highest numbers of waterfowl winter. surprising).This may be true, to a lesserextent, for the As well as capturing healthy prey, the eaglesprobably smaller mammals as well. On the other hand, large num- alsotook injured or dead birds, assuggested by the pres- bers of waterfbwl winter in the Amvrakikos wetlands, in- ence of lead shot in two pellets. The presence of lead cluding up to 100000 ducksand cootsin certain years. shotin the pelletsindicated that the Greater SpottedEa- The eaglesmostly hunt prey fi•omperches (often on low gle fed on birds shot, but not retrieved by hunters (see tamarisk, Tamarixspp.), or from embankments,or pa- also Hallmann 1989). Lead shot is considered to be a trolling by gliding low over extensivewetland areas, seriousthreat fbr many wetland raptors,such as the West- 374 SHO[tT COMMUNICATIONS VOL. 38, NO. 4 ern Marsh-Harrier (Circusaeruginosus) in France (Pain et de l'aigle criard (Aquila clanga)en Moselle. Ciconia16' al 1997). Therefore, the potential effect of lead shot on 117-125. the should be investigated. GALUSmN,V.M. 1962. The Greater Spotted Eagle in the Stands of trees, which provide perches for look-outs valley of the Oka River and its influence in the num- and roosting,are important for the hunting eaglesand bers of some birds. Uch. Zap. Mosk. Pedagog.Inst. Len- should be protected. Riparian woodlotsand large trees ina. 186:115-151. are often cut by local inhabitants, and thus roost sites HALLMANN,B. 1989. Status and distribution of Aquila in (actual or potential) may be threatenedby this activity. Greece. Biol. Gallo-Hell. 15:171-176. Poisoningis alsoa potentialthreat. Becauseseveral un- HANDPdNOS, G. AND T. AKP,IOTtS. 1997. The birds of authorized refuge dumps exist in the AmvrakikosWet- Greece. Christopher Helm, London, U.K. lands, the threat of poisoning through scavengingat IVANOVSK¾,V. 1996. Notes on the breeding biology of dumps is present. Also, eaglescould feed on poisoned spotted eaglesAquila clangaand A. pomarinain Bye- carrion laid out illegally by local fhrmers for deterring lorussia. Pages 297-299 in B.-U. Meyburg and R.D. foxes and other canines. Therefore, extent of scavenging Chancellor lEDS.], Eagle studies. World Working and the susceptibilityof the Greater Spotted Eagle to Group on Birds of Prey and Owls, Berlin, . such poisoning should be investigated. MACDONALD,D. ANDP. BARRETT.1993. Collins field guide: mammalsof Britain and Europe. Harper CollinsPub- RESUMEN.--Seexamin6 la dieta de figuilasAquila clanga lishers, London, U.K. en los humedales de Amvrakikos en el oeste de Grecia MEYBURG, B.-U., L. HARASZTHY, M. STRAZDS, AND N pot medio de an/tlisisde egagr6pilas.Con baseen el nfi- SCHAFFE•t.2001. European species action plan for mero de presas, la dieta estuvo compuesta principal- Greater Spotted Eagle (Aquila clanga).Pages 1-16 in mente pot aves (84.2%) y pot cantidadesmenores de N. Schaffer and U. Gallo-Orsi [EDs.], European msectos(5.3%), mamiferos(4.2%), reptiles (3.2%), pe- Union action plansfor eight priority bird species.Eu- ces (2.1%) y antibios(1.1%). Las avesfueron suprema- ropean Commission,Brussels, Belgium. mente importantesen tfirminosde biomasa(94.6%); las MOLTONI,D.E. 1943. L'alimentazione dell' aquila ana- presasprincipales rueton patos del g•nero Arias, y los traia (Aquilaclanga). Riv. Ital. Ornitol.13:97-100. r/tlidos Gallinula chloropusy Fulica atra. La gran mayoria PA•N,D.J., C. BAVAUX,AND G. BUP,NELEAU. 1997. Seasonal de las presascorrespondi6 a especiesque se encuentran blood concentration of lead in Marsh Harrier Circus casi exclusivamente en humedales. aeruginosusfrom Chaferite Maritime (France): rela- [Traducci6ndel equipo editorial] tionshipwith the hunting season.Biol. Conserv.81:1- 7. ACICNOWI,EDGMENTS PAN•dN,N.S. 1972. On the f•eding of the GreaterSpotted We are grateful to OIKOS-Nature Management, Ltd., Eagle (Aquila clanga)pallas in the Bureya River Valley who supported this study,and in particular to T. Arapis, (Amur region). Pages 331-333 in Zoological prob- G. Rigas, and V. Hatzirvassanis.We are also grateful to lems of . NAUKA, Novosibirisk, Russia. the wardens and other field workers of the LIFE-Nature PRIKLONSKY,S.G. 1960. On the food of the Greater Spot- project, and in particular to K. Floudas and Y. Rousso- ted Eagle at the mouth of the Belaya River. Ornitol.3' poulos.We alsothank A. Dimitropoulosand I. Schogolev 174-179. for the translation of the Russian articles and Dr. V. Gout- her for his valuable commentson the original draft. We Q•NGX•A,Z. 1996. Winter ecologyof Aquila clangain Lis- also appreciate B.-U. Meyburg, D. Ontiveros, and an hah Nature Reserve.SichuanJ. Zool. 15:170-172. anonymous reviewer for their comments on an earlier TUC•E}L G.M. AND M.F. HEATH. 1994. Birds in Europe, draft of this manuscript. their . BirdLife Conservation Se- ries No. 3. BirdLife International, Cambridge, U.K. LI I'ERATURE CITED V•ACHOS,C.G. ANDN.K. PAPAGEORGIOU.1996. Breeding BROWN,R., J. FER(;t•SON,M. LAWR•N(:E,AND D. LEES. biology and feeding of the LesserSpotted Eagle Aq- 1987. Tracksand signsof the birds of Britain and Eu- uila pomarinain Dadia Forest, north-eastern Greece rope: an identificationguide. ChristopherHelm, Lon- Pages337-347 in B.-U. Meyburgand R.D. Chancellor don, U.K. [EDs.], Eagle studies.World Working Group on Birds CHINERY,M. 1993. Collins field guide: insectsof Britain of Prey and Owls, Berlin, Germany. and northern Europe. Harper-Collins Publishers, London, U.K. Received 10 December 2003; accepted 23 September FP,ANCO•S, J. 1992. Observationssur la presencehivernal 2004