Ardeola 48(2), 2001, 183-190

THE DECLINE OF THE BEARDED GYPAETUS BARBATUS IN

Stavros XIROUCHAKIS*, Anastasios SAKOULIS** & Giorgos ANDREOU*

SUMMARY.—The decline of the Bearded Vulture Gypaetus barbatus in Greece. The Bearded Vulture Gy- paetus barbatus is considered to be an endangered species in Greece. The latest estimate in the mid 80s gave a population of about 25 pairs distributed over an area of about 8000 km2. In an attempt to update our knowledge on the post-1980 distribution and status of the species, we gathered all bibliographical references for the period 1985-1999 and conducted a field survey (1995-2000) in almost all traditional territories. Results revealed that an 84% loss of the species’ population and a 75% shrinkage of its breeding distribution have ta- ken place during the last decade. The present population consists of four breeding pairs that are distributed over 2000 km2 in or an estimated 25 individuals. Population decline has been most pronounced in the mainland (>90% loss), where only one pair seems to have been left in the borders with the former Yugosla- vian Republic of Macedonia. Poisoning and direct persecution seem to have had the most serious impact on the species’ decline. Conservation actions such as safeguarding of nesting areas and reduction of human per- secution are urgently needed for the long-term survival of the Greek population of Bearded . Key words: Distribution, disturbance, Greece, Gypaetus barbatus, illegal shooting, poisoning, population size.

RESUMEN.—El declive del Quebrantahuesos Gypaetus barbatus en Grecia. El Quebrantahuesos Gypaetus barbatus es una especie en peligro de extinción en Grecia. La última estima poblacional, realizada a media- dos de los años 80, resultó en 25 parejas, distribuidas en un área de unos 8000 km2. En un intento de ampliar nuestro conocimiento sobre la distribución y estatus de la especie en los años posteriores a 1980, recopilamos todas las referencias bibliográficas del periodo 1985-1999 y realizamos un trabajo de campo (1995-2000) en casi todos sus territorios tradicionales. Los resultados revelaron que durante la última década se ha reducido la población de la especie en un 84% y que ha sufrido una pérdida del 75% en su área de distribución como reproductora. La población actual cuenta con cuatro parejas reproductoras distribuidas en un área de 2000 km2 en Creta, o una estima de 25 individuos. La reducción de la población ha sido más pronunciada en la región continental (con una pérdida de más del 90%), donde tan solo una pareja parece permanecer en los límites con la República de Macedonia. El envenenamiento y la persecución directa parecen haber tenido el impacto más grave sobre la supervivencia de la especie. Acciones de conservación, como el salvaguardar las áreas de cría o la reducción de la persecución humana, son necesarias y urgentes para asegurar la supervivencia a largo pla- zo de la población griega de Quebrantahuesos. Palabras clave: Caza ilegal, envenenamiento, Gypaetus barbatus, distribución, perturbación, Grecia, ta- maño poblacional.

INTRODUCTION in Europe, Northern Africa, Asia Minor, Midd- le East and reaches up to Mongolia and , The Bearded Vulture Gypaetus barbatus is a and the somewhat smaller, with no black ear cliff-nesting raptor that inhabits mountain re- tufts, Gypaetus barbatus meridionalis, that oc- gions of and Africa (Cramp & Sim- curs in East and . The Bearded mons, 1980). It has been classified in up to five Vulture feeds primarily on bones of small- and subspecies (Dementiev & Gladkov, 1966; medium-sized carcasses coming from wild ani- Brown & Amadon, 1968; Glutz von Blozheim mals or domestic ungulates in areas of extensi- et al., 1971), although Hiraldo et al. (1984) dis- ve pastoral activity (Hiraldo et al., 1979; tinguish only two on the basis of plumage pat- Cramp & Simmons, 1980; Brown & Plug, terns: Gypaetus barbatus barbatus, that occurs 1990; Heredia & Heredia, 1991).

* Natural History Museum of Crete. University of Crete, P.O. Box 2208, 71409 Crete, Gree- ce. e-mail: [email protected] ** Hellenic Ornithological Society. Em. Benaki 53, 10681 Athens, Greece. E-mail: [email protected] 184 XIROUCHAKIS, S., SAKOULIS, A. & ANDREOU, G.

The bulk of its population is concentrated in HOS archives in the last 15 years and Central Asia and the (del Hoyo et mapped them on 1:50000 maps acquired al., 1994) while in Europe the species is regar- at the Military Geographical Service. In ded as endangered since it has disappeared from an attempt to validate many of these ob- most Central European countries during the servations, we crossed references to the XIXth and the XXth centuries (Bijveleld, 1974). same mainly on the basis of the pro- The present European population consists of no ximity of their geographical location. Mo- more than 120 breeding pairs which are distri- reover, we searched in detail the Stan- buted in the Pyrenees (Spain, France), the is- dard Data Forms of the review of the lands of Corsica (France) and Crete (Greece), Important Areas (IBA) inventory in and the (France, Switzerland, , Aus- Greece. Fieldwork for the IBA network tria), where the species has been reintroduced update took place during the years 1995- (Tucker & Heath, 1994; Frey & Llopis, 1995; 1997, and in that period almost all moun- Xirouchakis & Giannatos, 1997; Heuret & tain areas of Greece were visited. Rouillon, 1998; Fasce, 1999; Heredia & Razin, 3. Personal communications. We collected 1999; Hofbauer-Hofer, 1999). and checked all sightings of the species In Greece, the Bearded Vulture was com- reported by people active in mountain mon in the beginning of the XXth century and areas (e.g. forestry staff, nature lovers, was present in almost all continental massifs climbers, stockbreeders, birdwatchers and and mountains of Crete (Glutz et al., 1971; wildlife biologists) for the period 1990- Handrinos, 1985). It was even reported as exis- 1995. We assessed the reliability of these ting on the island of Rhodes (Salvatori & Festa, records by asking the actual observers for 1913; Tortonese & Moltoni, 1947). However, it a detailed description of the species (e.g. declined dramatically in the very last decades body shape, silhouette, plumage and (Grubac, 1991; Tucker & Heath, 1994; Han- flight behavior). drinos & Akriotis, 1997), possibly due to: (a) 4. Fieldwork. In an attempt to confirm site habitat loss and degradation; (b) disturbance at occupancies in continental Greece, we vi- nesting sites; (c) food shortage; (d) indirect poi- sited the traditional areas of the species soning from illegal use of poisoned baits; and and searched all territories that had been (e) direct persecution by man. In this paper we reported to be active at least till early review data available on its status over the last 1990s, namely the mountains of Parnas- 20 years, aiming at determining its current dis- sos, Giona, Vardousia and Olympos. We tribution and population size. Reasons for the surveyed typical Bearded Vulture habi- decline and conservation actions in need are tats such as upland pastures and the alpi- also discussed. ne zone above the treeline during the ye- ars 1998 and 1999. In addition, an average of 10 days per month was spent MATERIAL AND METHODS in the field during the years 1996-2000 in the island of Crete in all areas located Information on the population size and bree- over 400 m a.s.l. Fieldwork took place ding distribution of the species in Greece in from early morning to sunset although ef- the 1980s and 1990s was obtained from the fo- fective searching effort ranged from 3 to llowing sources: 11 hours per day.

1. Bibliographical references and unpubli- Observations were made mainly from vanta- shed reports. Although the literature on ge points with good view over the sampling the status of the species is limited, we re- areas by using 10x50 binoculars and 30-60x viewed and assessed the few existing pa- spotting telescopes. Bird sightings were also pers and relevant data in official and un- mapped on 1:50000 maps. To estimate popula- published reports. tion size we paid particular attention to recor- 2. Archives of the Hellenic Ornithological ding individuals of different ages. Classification Society (HOS). We considered all Bear- was based on plumage patterns (Forsman, ded Vulture observations listed in the 1999), and we allocated each vulture sighted

Ardeola 48(2), 2001, 183-190 THE DECLINE OF THE BEARDED VULTURE GYPAETUS BARBATUS IN GREECE 185 to one of four age classes: juvenile (0 until 21- both birds were present but no breeding activity 24 months), immature (21-43 months), sub- occurred, constituted a Bearded Vulture terri- adult (43-60 months) and adult (> 60 months). tory (Heredia & Heredia, 1997). We defined as core areas of Bearded Vulture For the breeding distribution of the species, the sites of major activity (Brown, 1984), we regarded the IBAs that had supported Bear- which incorporated one or more of the follo- ded Vulture territories during the last two de- wing features: (a) nests; (b) summer and winter cades (Grimmett & Jones, 1989). Relevant si- roosts; (c) bone storage sites (e.g. old nests, zes of these areas were derived from the potholes, rock crevices) and bone dropping are- reviewed IBA inventory (Heath & Evans, as, and (d) rocky outcrops producing thermal 2000). currents suitable for soaring that were regularly used by the birds. The location of these sites were registered with the use of the Global Po- RESULTS AND DISCUSSION sitioning System (GPS) and plotted on a LAT/ LONG map by applying the DMAP program The total range of the species has contracted (Morton, 1999). Core areas that had been oc- considerably during the last two decades in all cupied by a breeding pair or a solitary adult, as mainland massifs and, to a lesser extent, in the well as traditional nesting areas where one or mountains of Crete (Fig. 1). Table 1 lists the

FIG. 1.—Distribution of Bearded Vulture in Greece in the 1980s (hatched area) and the 1990s (solid black area). [Distribución del Quebrantahuesos en Grecia en los años 80 (área rayada) y en los años 90 (área oscura).]

Ardeola 48(2), 2001, 183-190 186 XIROUCHAKIS, S., SAKOULIS, A. & ANDREOU, G.

TABLE 1

Breeding distribution of the Bearded Vulture in Greece in the 1980s and 1990s. [Distribución del área de cría del Quebrantahuesos en Grecia en los años 80 y 90.]

IBA name Size (km2) [Nombre de la IBA] [Tamaño (km2)] 1980s 1990-1995 1995-1999

Mainland [Continente] 1. Vouna Evrou 740 + + – 2. Koilada Filiouri 770 + – – 3. Oros Tzena 131 – + ? 4. Koryfes Orous Voras 520 + – – 5. Olympos Mountain 420 + + – 6. Oros Othrys 840 + + – 7. Kerketio Oros (Koziakas) 230 + – – 8. Ori Athamanon (Tzoumerka) 550 + – – 9. Oros Tymfi 550 + – – 10. Ori Vardousia 210 + + – 11. Oros Giona 250 + + – 12. Oros Parnassos 194 + + – 13. Ori Agrafa 212 + + –

Crete [Creta] 14. Krioneritis Mountain 150 + + – 15. Koutroulis - Ag. Dikaios 200 + + + 16. Lefka Ori 540 + + + 17. Oros Kedros 120 + + + 18. Oros Idi (Psiloritis) 440 + + + 19. Asterousia Ori (Kofinas) 290 + + – 20. Oros 540 + + + 21. Oroi Thrypti kai Ornon 150 + + +

Number of sites [Número de emplazamientos] 20 16 6

Total range (km2) 7916 5427 1990 [Extensión total]

IBAs where Bearded Vulture territories were become extinct. There were about 25 breeding found in the 1980s and in the 1990s. Out of pairs during the 1970s and possibly early the 20 sites where the vulture was proved to 1980s, with 11-13 pairs in the mainland and breed or regarded as a breeding species until 12 in Crete (Handrinos, 1985). The species still the late 1980s, only six supported active pairs held 18 territories up to the mid 1990s. Five in the late 1990s, all of them located in Crete. were located in continental Greece with 1-2 ac- Taking into consideration that not all habitats tive pairs in Parnassos and Giona mountains within this area (ca. 8000 km2) were equally and a handful of birds scattered in the massifs suitable for the species, the present breeding of Tzena, Eastern Rodopi and Olympos. The distribution covers an area of about 2000 km2 remainder (13 territories) were located in Crete, revealing a minimum shrinkage of 75%. where there were 10 pairs and a few single Regarding its population size, the Bearded birds (Fig. 2). Vulture has suffered a loss of 84% in less than After 1996, the Bearded Vulture population two decades. The decline was most pronounced continued to decline resulting in only one pair in the mainland, where the species is about to in continental Greece, on the borders with the

Ardeola 48(2), 2001, 183-190 THE DECLINE OF THE BEARDED VULTURE GYPAETUS BARBATUS IN GREECE 187

FIG. 2.—Bearded Vulture territories in Crete in 1999. [Territorios del Quebrantahuesos en Creta en 1999).] former Yugoslavian Republic of Macedonia. ding pairs, which are the last in Greece, and Reproduction in the rest of the mainland seems probably in the Balkans (Table 2). The number unlikely after 1995, when the last observation of juvenile and immature birds is chronically concerning a juvenile bird took place between small and ranges from 23-38% of the total po- the Vardousia and Giona mountains (Hatzivar- pulation, revealing a low reproductive output sanis, pers. com.). In Crete, the population see- and/or a low juvenile survival (Table 2). med rather stable, but only if the previous esti- The reasons for the species decline in the mates of 10-12 pairs were accurate (Vagliano, mainland remain largely unknown, although 1981; Hallmann, pers. com.). During the pe- the indiscriminate laying out of poisoned baits riod 1996-2000, the Cretan population follo- for mammalian carnivores is suspected to have wed the previous mainland’s trend, i.e. a rapid been the main one (Poirazidis et al., 1995; An- increase of the number of territories occupied toniou et al., 1996; Papakonstantinou, 1998). by single birds. At present, the island hosts no Solitary-nesting such as the Bear- more than 25 individuals including four bree- ded Vulture that feed on small carrion are most

TABLE 2

Age class distribution of the Bearded Vulture population in Crete. [Distribución de las clases de edad de la población de Quebrantahuesos en Creta.]

Age–group [Grupo de edad] 19811 19922 19963 19984 19995 20005

Juvenile [Juvenil] 216532 Immature [Inmaduro] 5–4744 Sub–adult [Sub-adulto] –61210 Adult [Adulto] 23 45 20 22 22 18 Undetermined [Sin determinar] –6–––– Total number of individuals [Número total de individuos] 30 58 31 36 30 24 Total number of pairs [Número total de parejas] 10-12 14-16 9 10 7 4

1 Vagliano, 1981; 2 Hallmann, pers. com.; 3 Xirouchakis & Giannatos, 1997; 4 Xirouchakis et al., 1999; 5 This study.

Ardeola 48(2), 2001, 183-190 188 XIROUCHAKIS, S., SAKOULIS, A. & ANDREOU, G. susceptible to poisoned baits (Brown, 1991). cies are placed at a distance shorther than one Poisoning can hardly be documented, but it has kilometer from a road (this study). This high recently been proved to be the primary source density of roads in the vicinity of nest and ro- of the species mortality in the Pyrenees (Antor, osting sites may induce a high potential of hu- 1999). man disturbance, and is inversely related to the Natural causes or potential limiting factors, species’ breeding success (Donázar et al., such as scarcity of nest sites and food availabi- 1993). lity (Newton, 1979), appear to have had little or The conservation of the species has been no importance. All mainland massifs still offer quite problematic. The Bearded Vulture occu- good nesting opportunities, while reduction in pies enormous home ranges (i.e., 300-400 km2; food supply cannot explain the disappearance this study), where a combination of threats may of the species in just five years. Bearded Vul- occur. In the meantime, adult birds show re- tures, as bone scavengers, can afford food shor- markable site fidelity and prefer to occupy tra- tage more than any other vulture species (Hous- ditional core areas in degraded territories than ton & Copsey, 1994). Moreover, the mountain neighbouring ones with less human pressure. complex of Vardousia-Giona-Parnassos, which So far, most conservation actions have been has been the historical stronghold of the species orientated towards the designation of Bearded (7-8 breeding pairs in Parnassos Mt. alone; Vulture core areas as Special Protection Areas Krueper, 1862), still hosts about 190000 trans- under the Birds Directive 79/409/EEC. Moreo- humant livestock (National Statistical Service, ver, management plans have already been ela- pers. com.). borated for some of those sites, while in Crete a Food shortage was much more unlikely in supplement-feeding scheme is under way (Xi- Crete, where more than one million and rouchakis, 1998). Nevertheless, in the main- goats (both transhumant and semi-feral) exist land, the species recovery seems almost im- (Ministry of Agriculture, pers. com.). On the possible. A reintroduction project would be the contrary, there is evidence for the impact of ultimate solution, but the release of captive- human persecution. At least seven birds have bred individuals might result in a waste of time been found shot or verified of being so during and funds as long as bait use prevailed. In Cre- the last ten years (Table 3). Shooting could te, the presence of solitary birds with no mate is have been favoured by the vast network of expected to increase if the shooting of raptors track roads, constructed for the promotion and continues. The sub-adult/adult ratio of the is- reinforcement of pastoralism or fire protection land population has been 1:20, meaning that a that has been developed in the island. At pre- high adult mortality could hardly be compen- sent, an average of 1.5 km of track road lies in sated by potential replacements. The enforce- every square kilometer of Bearded Vulture te- ment of the law and the rise of public aware- rritories and 63% of the core areas of the spe- ness are the most urgent conservation measures

TABLE 3

Incidences of direct persecution of Bearded Vultures in Crete (1990-2000). [Incidencias de la persecución directa del Quebrantahuesos en Creta (1999-2000).]

Area Year Age State Source [Área] [Año] [Edad] [Estado] [Referencia]

Dikti 1991 Adult [Adulto] Shot [Disparado] Vagliano, pers. com. Dikti 1992 Adult Shot Frey, 1994 Dikti 1993 Immature Shot and stuffed This study [Inmaduro] [Disparado y disecado] Lefka Ori 1997 Immature Shot and stuffed This study Lefka Ori 1998 Immature Shot and stuffed This study Idi 1998 Adult Shot This study Idi 2000 Adult Shot This study

Ardeola 48(2), 2001, 183-190 THE DECLINE OF THE BEARDED VULTURE GYPAETUS BARBATUS IN GREECE 189 in order to reduce direct persecution. Until then, DEL HOYO, J., ELLIOT, A. & SARGATAL, J. 1994 the long-term survival of the species in its last (Eds.). Handbook of the Birds of the World, Vol. 2. stronghold in Greece and in the rest of the Bal- New World Vultures to Guinea fowl. Lynx Edi- kans looks rather uncertain. tions. Barcelona. DEMENT’EV, G. P. & GLADKOV, N. A. 1956. Birds of the Soviet Union. Vol. I. program for scien- tific translations. Jerusalem. ACKNOWLEDGEMENTS.—We are very grateful to FASCE, P. 1999. Reproduction of the Corsican Bear- C. Misiakos, V. Hatzivarsanis, B. Grubac, R. Tsiaki- ded Vulture population from 1976 to 1999. In, H. ris, H. Papaioanou and C. Poirazidis for providing us Frey, G. Schaden & M. Bijleveld (Eds.): Bearded with their personal observations, G. Arnellos and G. Vulture Annual Report, pp. 57. Foundation of the Roussopoulos for their assistance in fieldwork and C. Conservation of the Bearded Vulture. Wassena- Grivas for collecting some of the data on pastoralism. ar. The Netherlands. We also thank the Hellenic Ornithological Society FREY, H. 1994. The Situation of the Bearded Vulture for allowing us access to its archives, the Natural (Gypaetus barbatus) in the Mediterranean Coun- History Museum of Crete for technical support, J. J. tries. In, H. Frey, G. Schaden & M. Bijleveld Negro and an anonymous referee for comments on (Eds.): Bearded Vulture Annual Report, pp. 54- the manuscript and S. Roberts for improving the En- 61. Foundation of the Conservation of the Bearded glish. This study has been partially funded by a LIFE Vulture. Wassenaar, The Netherlands. project of the European Union (B4-3200/98/444). FREY, H. & LLOPIS, A. 1995. Situación actual del proyecto de reintroducción del Quebrantahuesos Gypaetus barbatus en los Alpes. In, R. D. Chan- BIBLIOGRAPHY cellor, B. U. Meyburg & J. J. Ferrero (Eds.): Ho- larctic Birds of Prey, pp. 395-403. Badajoz. Ex- ANTOR, R. 1999. Evolución demográfica de la po- tremadura. blación: Estimación de las tasa de supervivencia y FORSMAN, D. 1999. The Raptors of Europe and el tamaño de la población pre-adulta de Quebran- Middle East: A Handbook of Field Identification. tahuesos en el Pirineo. 1.a parte. Fundación para T. & A. D. Poyser. London. la conservación del Quebrantahuesos, 2: 17-24. GLUTZ VON BLOTZHEIM, U., BAUER, K. M. & BEZ- ANTONIOU, V., ZANTOPOULOS, N., SKARTSI, D. & ZEL, E. 1971. Handbuch Der Vogel Mitteleuro- TSOUKALI-PAPADOPOULOU, H. 1996. Pesticide poi- pas. Vol. 4. Falconiformes. Akademische Ver- soning of of wild fauna. Veterinary Hu- lagsgesellschaft. Frankfurt am Main. man Toxicology, 38: 212-213. GRIMMETT, R. F. A. & JONES, T. A. 1989 (Eds.). Im- BIJLEVELD, M. 1974. Birds of Prey in Europe. Mac- portant Bird Areas in Europe. ICBP Technical Millan Press Ltd. London. Publication No. 9. Cambridge. BROWN, L. H. & AMADON, D. 1968. , GRUBAC, B. 1991. Status and Biology of the Bearded and of the world. Country Life Books. Vulture Gypaetus barbatus in Macedonia. Birds of Hamlyn. London. Prey Bulletin, 4: 101-117. BROWN, C. J. 1984. Foraging and home range in the HANDRINOS, G. 1985. The Status of vultures in Gree- Bearded Vulture. In, J. M. Mendelsons & C. W. ce. In, I. Newton & R. D. Chancellor (Eds.): Con- Sapsford (Eds.): Proceedings of the 2nd Sympo- servation studies in raptors, pp. 103-115. ICBP sium on African Predatory Birds, pp. 45-46. Natal Technical Publication, No 5. WWGBP. Salonica. Bird Club and Durban Natural History Museum. HANDRINOS, G. & AKRIOTIS, T. 1997. The Birds of Durban. Greece. Helm A. & C. Black. London. BROWN, C. & PLUG, I. 1990. Food choice and diet of HEATH, M. F. & EVANS, M. 2000 (Eds.). Important the Bearded Vulture Gypaetus barbatus in Sou- Bird Areas in Europe. Priority sites for conserva- thern Africa. South African Journal of Zoology, tion. Birdlife Conservation Series No. 8. BirdLife 25: 169-177. International. Cambridge. BROWN, C. 1991. An investigation into the decline of HEREDIA, R. & HEREDIA, B. 1991. (Eds.) El Que- the Bearded Vulture Gypaetus barbatus in Sou- brantahuesos (Gypaetus barbatus) en los Pirineos. thern Africa. Biological Conservation, 57: 315-337. Características ecológicas y biología de la con- CRAMP, S. & SIMMONS, K. E. L. 1980. (Eds.) The servación. ICONA. Madrid. Birds of the Western Palearctic. Vol. II. Oxford HEREDIA, B. & HEREDIA, R. 1997. European Union University Press. Oxford. Species Action Plan. Lammergeier (Gypaetus bar- DONÁZAR, J. J., HIRALDO, F. & BUSTAMANTE, J. batus). http://europa.eu.int/comm/environment/ 1993. Factors influencing nest site selection, bree- nature/directive/birdspriority.htm ding density and breeding success in the bearded HEREDIA, R. & RAZIN, M. 1999. Ecology and Con- vulture (Gypaetus barbatus). Journal of Applied servation of the Bearded Vulture: The case of the Ecology, 30: 504-514. Spanish and French Pyrenees. In, M. Probonas,

Ardeola 48(2), 2001, 183-190 190 XIROUCHAKIS, S., SAKOULIS, A. & ANDREOU, G.

S. Xirouchakis & C. Papazoglou (Eds.): Procee- Conservation in Europe. Progress, pp. 35-43. dings of the Bearded Vulture workshop, pp. 29-45. Conservation Foundation. Mallorca. Natural History Museum of Crete. Iraklion. Crete. SALVATORI, T. & FESTA, E. 1913. Escursioni Zoolo- HEURET, J. & ROUILLON, A. 1998. Première repro- giche Del Dr. E. Festa nell’ isola di Rodi. II. Uc- duction réussie de Gypaètes barbus Gypaetus bar- celli. Bolletino del Museo Zoologico di Torino, batus issus de réintroduction dans Alpes (Haute- 28: 1-23. Savoie, France): Observations comportamentales TORTONESE, E. & MOLTONI, E. 1947. Appunti orni- du couple et du jeune. Nos Oiseaux, 45: 199-207. thologici relativi all’isola di Rodi (Egeo), 1942-43. HIRALDO, F., DELIBES, M. & CALDERON, J. 1979. El Rivista Italiana di Ornitologia, 17: 29-39. Quebrantahuesos Gypaetus barbatus. ICONA. TUCKER, G. M. & HEATH, F. A. 1994. Birds in Euro- Madrid. pe: Their . Birdlife Internatio- HIRALDO, F., DELIBES, M. & CALDERON, J. 1984. nal Cambridge. Comments on the of the Bearded Vul- VAGLIANO, C. 1981. Contribution au statut des rapa- ture Gypaetus barbatus (Linnaeus, 1758). Bonner ces diurnes et nocturnes nichêurs en Crete. In, Ra- Zoologische Beitrage, 35: 91-95. paces mediterranéens, pp. 14-16. Annales du HOFBAUER-HOFER, K. 1999. The Bearded Vulture CROP. 1. Aix-en-Provence. reintroduction project in the Alps. In, M. Probonas, XIROUCHAKIS, S. & GIANNATOS, G. 1997. Prelimi- S. Xirouchakis & C. Papazoglou (Eds.): Procee- nary Results on the Status of Lammergeier in Cre- dings of the Bearded Vulture workshop, pp. 51. te. In, H. Frey, G. Schaden, & M. Bijleveld (Eds): Natural History Museum of Crete. Iraklion. Crete. Bearded Vulture Annual Report, pp. 50-53. Foun- HOUSTON, D. J. & COPSEY, A. J. 1994. Bone diges- dation of the conservation of the Bearded Vulture. tion and intestinal morphology of the Bearded vul- Wassenaar. The Netherlands. ture. Journal of Raptor Reaserch, 28: 73-78. XIROUCHAKIS, S. 1998. Conservation of the Bearded KRUEPER, T. 1862. Aus meine tagebuch. Journal für Vulture Gypaetus barbatus in Greece. In, H. Frey, Ornithologie, 10: 72-77. G. Schaden & M. Bijleveld (Eds): Bearded Vultu- MORTON, A. 1999. DMAP for Windows. Software re Annual Report, pp. 53-55. Foundation of the for Distribution Mapping. Internet Web Page: Conservation of the Bearded Vulture. Wassenaar. http://www.dmap.co.uk/ The Netherlands. NEWTON, I. 1979. Population ecology of raptors. XIROUCHAKIS, S., SAKOULIS, A. & PAPAZOGLOU, C. Poyser. Berkhamsted. 1999. Distribution and Status of the Bearded Vul- PAPAKONSTANTINOU, K. 1998. A poisoning incidence. ture (Gypaetus barbatus) in Greece. 8th European Oionos, 5: 7. Ecological Congress, 18-23 September 1999. Hal- POIRAZIDIS, K., SKARTSIS, T., PISTOLAS, K. & - kidiki. KAS, P. 1995. Greek Black Vulture population re- port for the period 1993-1995. In, E. Tewes, J.J. [Recibido: 8-9-00] Sanchez & M. Bijleveld (Eds.): Black Vulture [Aceptado: 25-5-01]

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