AQUILA 1992. VOL.: 99 (41^8)
OCCURENCE OF T H E LONG-LEGGED BUZZARD (BUTEO RUFINUS) IN T H E HORTOBÁGY BETWEEN 1976 AND 1991 Dr. Gábor Kovács Hortobágy National Park
Abstract
Occurence of the Long-legged Buzzard (Buteo rufinus) in the Hortobágy between 1976 and 1991 The most characteristic place of occurence of the Long-legged Buzzard in Hungary is the Hortobágy. During the penod between 1976 and 1991 this species was seek on a total of 232 óccasions in this area. During 1990—91 specimens staying here from spring to autum were noted and also overwintering ones in 1988-89. The increases in the number of oberseniations indicate the extension of the area of the Long-legged Buzzards and a slow growth in the population, inord accumulated during 15 years are analysed here, indluding the habitat requirements, feeding, behaviour and moult patterns of this speces.
Introduction Since the t u r n o f the Century occurrences o f the L o n g - legged B u z z a r d have been frequently observed by domestic bird-watchers. Occurence records o f this characteristic steppe predator o f East-Europe for the period between 1898 and 1959 have been reported by Sterbetz (1960), indicating nearly all the H o r t o b á g y data published until 1959. T h e series o f data i n c l u d i n g the entire territory o f H u n g a r y , even the regions beyond the frontier belonging to the C a r p a t h i a n Basin reveal that the Long-legged B u z z a r d has occured i n the Plain, the Eastern part o f the country. T h e Long-legged B u z z a r d was first observed i n the H o r t o b á g y i n 1908 (Szomjas, G . 1909) since then its presence has been reported more and more frequently (Szomjas, G. 1911, 1917, 1919; Szomjas, L., 1924; Újvárosi, 1925; Vasvári, 1928; Udvardy, 1941). Its occurrences i n the H o r t o b á g y have become so r e g u l ä r that not only o v e r s u m m e r i n g but a possible nesting o f the bird is suggested e. g., by U d v a r d y . T h i s latter has not been evidenced so far, however. D u r i n g the fifties and sixties the H o r t o b á g y was again the place most frequented by the species. (Lelovich 1962; Sóvágó, 1975; Sterbetz, 1967; 1972). Since 1970 it has often been watched by László Vilmos Szabó i n the Southern puszta areas (Horváth, Szabó, 1981). Fintha (1975) has collected several records on the b i r d i n the m i d d l e and N o r t h e r n parts o f the H o r t o b á g y . A g a i n Fintha c o u l d observe the most abundant colonies i n the 41
H o r t o b á g y (14-15 speciemens a day) in the district o f Ohat, Margita, Darássá and Bagota from 20 A u g u s t to 16 October, 1988. O n 6 October, 1987 he counted 2 2 - 2 5 specimens in a single grass field near H a j d ú b a g o s , representing the domestic record (Fintha, in litt).
Material and method D u r i n g period between M a y , 1976 and N o v e m b e r , 1991 I observed the Long-legged B u z z a r d in the H o r t o b á g y o n a total o f 232 occasions T h e additional data enables a more datailed analysis o f the migration which has taken place d u r i n g the last one and a half decardes. Besides, it is also noteworthy to mention some conspicious events such as early arrival, lateautumn occurence, succesfull overwintering, feeding observations and change o f habitats.
Spring arrival In the literature there is only one o l d d á t u m available on the s p r i n g migration o f the Long-legged B u z z a r d : on 6 april, 1925 Újvárosi watched the birds in the vicinity o f H a j d ú b ö s z ö r m é n y ( P r ó d ? Bagota ? ) (In: Warga, 1928). M y personal series o f data contain 7 s p r i n g observations: 26 M a y , 1976. Pentezug 11 A p r i l , 1982. Borzas 19 M a r c h , 1990. K u n m a d a r a s 30 M a r c h , 1990. Á g o t a 18 A p r i l , 1990. A n g y a l h á z a 6 April, 1991. K a r c a g 27 M a y Kunmadaras T h e first seven data between 19. M a r c h a n d 27. M a y ( d u r i n g 16 years) indicate an insignificant s p r i n g migration from w h i c h the Long-legged B u z z a r d can not be considered as a r e g u l ä r s p r i n g migrant in o u r region d u r i n g M a r c h and M a y . It is questionable, whether early data in 1990—1991 can be considered as a b e g i n n i n g o f a more frequent spring occurence, o r not? T h e Suggestion will only be answered d u r i n g the next years.
Summer occurence, oversummering Early-summer (early-June) data has become r e g u l ä r since the eighties. Since then the Long-legged B u z z a r d has been consired as a summer-autumn gest. Its earliest summer occurence was on 3 J u n e (1986, 1989). D u r i n g the first two months o f the summer their numbers amount only to 4—5 specimens but then there is a considerable increase d u r i n g late-summer. 42
Autumn occurence T h e m a x i m u m frequency o f the Long-legged B u z z a r d in the H o r t o b á g y is from early-September to mid-October. D u r i n g this period the birds occur i n all parts o f the puszta so that 4—5 or more specimens can be seen a day. A c c o r d i n g to my estimates (based o n visits o f to 8—10 areas within two-three days) o n an average 10-12, (since 1988 it has increased to 14 and 18) specimens are stayling simultaneously in the H o r t o b á g y . T h e late-October occurences are infrequent, and only expectional speci mens can be seen i n N o v e m b e r (1985, 1991. unpublished). Based o n personel data a n d those o f István Fintha (Pers. comm.) the first ten days o f October can be mentioned as an interesting assembling p e r i o d . T h e majority o f the birds immigrate from o u r area at mid-October.
Overwintering T h e r e are two records o f winter occurence or owerwintering in the literature. I n 1911-12 one case was reported in K a z á n a n d was considered for a l o n g time the only w i n t e r i n g record in the country (Lambrecht, 1913). D u r i n g the 1988/89 winter I continuously watched, and aduit specimen overwintering succesfully between 27 December a n d 13 M a r c h . Its overwinTable 1. Occurrences of the Long-legged Buzzard in the Hortobágy between 1976. and 1991. 1. táblázat. A pusztai ölyv 1976—1991 közötti hortobágyi előfordulásai Year
fa-
Earliest
Év
Adatok száma
Legkorábbi
1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991
9 7 4 3 6 5 9 13 18 16 20 17 28 24 23 30
Máj. 26. Júl.22.
Aug. 19. Aug. 23. júl.3.
4. Apr. 11.
Jún.
Júl.4. Jún.
19.
Jún.28. j ú n . 3. j ú n . 7. J ú n . 25. Jan.l.
Márc. 19. Ápr. 6.
Latest
Daily maximum sps. Legkésőbbi Napi maximum (pd.)
Okt. 8. Szept. 13. Szept. 29. Szept. 22. Okt. 9. Aug. 17. Okt. 4. Okt. 15. Okt. 29. Nov. 11. Szept. 26. Okt. 22. Dec. 27. Okt. 15. Okt. 20. Nov. 18. 43
2 2 1 2 1 2 1 2 2 4 2 3 5 2 4 2
Estimated stock of the Hortobágy, sps. A Hortobágy becsült állománya (pd.)
8-10 8-9 5-6 4-5 7-8 6-7 9-10 12-13 14-15 10-12 12-13 11-12 16-18 16-17 14-15 12-13
tering can be explained by a very dry vole-infestated summer followed by a mild winter poor in precipitation which offered abundant rodent food for the buzzard (Kovács, 1989). T h u s , winter occurence can be considered as an exceptional case.
Table 2. Monthly distiibution of the records on the Long-legged Buzzard (1976-1991) 2. táblázat. A pusztai ölyv-adatok (1976—1991) havi megoszlása No. of occurrence
Month Hónap
A megfigyelések száma
Jan. - Január Feb. - Február March - Március April-Április May - Május June—Június July-Július August - Augusztus Sept. - Szeptember Oct. - Október Nov. - November Dec. — December
2 2 4 3 2 14 42 65 56 39 2 1
Total: Összesen:
232
Habitat In the H o r t o b á g y the Long-legged B u z z a r d mainlv visits the dry habitats within these the order o f preference o f the habitat types is as follows: - loess bucks, barrows - sodic puszta-grass, sodic benches — Heids: stubble, ploughed stubble, alfalfa — c u l t ü r e environment: abandoned building, ruins, wells in the puszta, flood-gates, lightning rods, seratching posts, nature protection boards etc. For comparison the B i h a r records ( K o n y á r , Esztár, Nagykereki, H o s s z ú p á lyi, Biharkeresztes, Derecske) also originate from grassy puszta areas, arable land and barrows (Kovács, 1986; Fintha and Kovács, 1988). A c c o r d i n g to the observations of István Fintha (Pers. comm.) the Long-leg ged Buzzard also frequently occurs in the region o f S z a t m á r and Bereg, a forested environment. C o n t r a r y to this, it can occassionally be seen in the bigger forests o f the H o r t o b á g y most by on the edges o f the forests (Ohat, Margita, Ágota). T h e b i r d is absent from the í l o o d area forests. It is rather infrequent in aquatic habitats. I observed the species on some occasions but 44
only by fish-ponds and in rice-fields (Kovács, 1988). Lines o f trees marginating rivers, canals and woodspots i n the puszta are preferrend habitats. T h e specimens staying here for a longer p e r i o d use permanent sleeping places (wells, trees) even when leaving the grassy areas for feeding in arable land, stubble and alfalfa Fields. Some very characteristics sleeping places used over 10-15 years are e.g., the V a d á l l ó well at A n g y a l h á z a , the Ancsán well at Szelencés, the big poplar tree o f Redemtpus in the K u n m a d a r a s puszta and the r u i n e d sheep-fold o f the Elek farm at Cserepes.
Feeding data In the H o r t o b á g y i n the loess-buck grass a n d a r o u n d the burrows the g r o u n d squirrel (Citellus citellus) occurs frequently p r o v i d i n g the main prey not only for thejust spreading Saker (Falco cherrug) and the Imperial Eagle (Aquila heliaca) appearing here more a n d more regularly, but for the Long-legged B u z z a r d , as well. A t the resting places used regularly by the buzzards I f o u n d plenty o f casts containing mainly squirrel fragments (Kalotás, 1986.). Hamsters (Cricetus cricetus) a n d C o m m o n voles (Microtus arvalis) are also frequent items indicating the field activity o f the Long-leg ged Buzzards. Kalotás (1992) has f o u n d fragments o f locusts, grasshoppers and other insects i n the pellets collected u n d e r the sitting-tree o f an o v e r s u m m e r i n g specimen. I couldn't observe this frequently as the buzzard was p r e y i n g on these items while Walking. In 1985 watched a Long-legged B u z z a r d specimen p r e y i n g o n ayoung guineafowl i n the N a g y i v á n puszta, o n an other occasion it preyed o n hens o f 1-2 months o l d and ate them on the top o f a hayrick. I have never seen it p r e y i n g o n Carrions.
Behaviour T h e Long-legged B u z z a r d appears for the most part singly even i f its species-mates are present i n the area within eyeshot. It is seldom that the same sleeping tree is used by two specimens or that the specimens can approximate or tolerate one another within a distance o f 8 0 - 1 0 0 m . O n l y specimens circling in the air may f o r m a loose-group o f 3-4 birds. It may occur i n the Company o f other avian species, again while circling, accidentally. It is difficult to discover any regularity in such cases thus, I attempt only to give the o r d e r o f frequency o f the various species: B u z z a r d (Buteo buteo) Short-toed Eagle (Circaétus gallicus) Montagu's H a r r i e r (Circus py gargus) H e n H a r r i e r (Circus cyaneus) M a r s h H a r r i e r (Circus aeruginosus) Rough-legged B u z z a r d (Buteo lagopus) 45
White Storke (Ciconia ciconia) Lesser Spotted Eagle (Aquila pomarina) Impearial Eagle (Aquila heliaca) Black Stork (Ciconia nigra) Saker (Falco cherrug) I have frequently noticed that the Long-legged Buzzards sitting in stubbles (also i n corn-stubble), alfalfa fields have been s u r r o u n d e d by rook folks, (occasionally) feeding at a distance o f 20—30 m . T h e wild geese visiting sowings, a n d corn-stubble in big masses are more watchful and often frightened o f the predator flying there. D u r i n g field observations the Long-legged Buzzards have appeared distrustful and watchful o n nearly every occasion. Fortunately, I met some very tarne specimens approachable to 4 0 - 5 0 m , contrary to the usual 100-120m.
Young specimens, colour variations, moult Based on feathers, approximately 80—90 % o f Long-legged Buzzards appearing on the H o r t o b á g y are o l d and even senile. In certain years no y o u n g birds were seen whilst, in other years 3—4 y o u n g specimens occured. T h e specimens belonging to the red-colour variety occur with a frequency o f 15-20%, c o m p a r e d to the more frequent light-coloured variety with the occasional presence o f gull — coloured senile specimens with white-tails. M o u l t i n g o f birds staying here takes place by the end o f summer. Plenty o f different feathers were collected from their resting palces (wells, barrows, ruins) and under the sleeping trees, e. g., tail feathers suitable for aging.
Series of datas accumulated during 16 years T h e data collecting sites included not only the territory o f the H o r t o b á g y National Park, but unprotected parts o f the Puszta and surroundings o f the nearby Settlements (Karcag, P ü s p ö k l a d á n y , N á d u d v a r , T i s z a f ü r e d , Egyek, T i s z a ö r s , B a l m a z ú j v á r s o ) , as well. Instead o f listing, the Observation data is tabulated indicating the total records, the earliest and latest dates as well as the m a x i m u m daily n u m b e r o f specimens a n d the estimated stock o f the H o r t o b á g y according to year (Table 1). T a b l e 2 represents the monthly distribution o f the data.
Acknowledgement I want to express my thanks to István Fintha head o f nature protection department ( H N P ) for his k i n d consent to publish his records obtained in the H o r t o b á g y , H a j d ú b a g o s and the S z a t m á r - B e r e g region. T h e k i n d assistance Sándor Konyhás offered d u r i n g the field visits in the Southern-East puszta areas o f the H o r t o b á g y is also acknowledged. 46
REFERENCES - I R O D A L O M
Fintha, I. (1976): Ritkább ragadozómadarak a Hortobágyon 1973-ban. Aquila, 82. 232. Fintha, I.-Kovács, G. (1988): Pusztai ölyv. In: Haraszthy L . (szerk.) Magyarország madárvendégei. 50-51. Horváth, L.-Szabó, L. V. (1981): The Ornis of the Hortobágy. In: The Fauna of the Hortobágy National Park. 391-407. Kalotás, Zs. (1986) Adatok ragadozómadaraink táplálkozásához. Mad. Táj. 1986. okt.-dec. 27-31. Kalotás, Zs. (1992) Néhány adat a Hortobágyon vendégeskedő pusztai ölyvek (Buteo rufinus) táplálkozásához. Mad. Táj. jan.-jún. (in print.) Kovács, G. (1986): Madártani megfigyelések Hosszúpályi, Konyár és Esztár kör nyékénekszikes tavain (1969-1984). Bihari Múz. Évk. I V - V . 5-26. Berettyóújfalu. Kovács, G. (1988): A Hortobágy madárvilágának öko-faunisztikai vizsgálata, 19711986. In: Tóth A . (szerk.): Tudományos kutatások a Hortobágyi Nemezti Parkban, 1976-85. 113-208. Kovács, G. (1989): Pusztai ölyv (Buteo rufinus) áttelelése a Hortobágyon. Mad. Táj. 1989/3-4. 34. Lambrecht, K. (1913): A z 1911/1912. évi télen áttelelt fajok jegyzéke. In: A madárvo nulás Magyarországon... Aquila, 20.127. Lelovich, Gy. (1962): A Hortobágy ragadozó madarai. Aquila, 67-68. 208-210. Sóvágó, M. (1975): Hortobágyi madármegfigyeléseim. Hajd. Múz. Évk. II. 21-49. Hajdúböszörmény. Sterbetz, I. (i960): Der Adlerbussard (Buteo rufinus) in Ungarn. Ornith. Mitteil. 12. 187-198. Sterbetz, 1. (1965): 1964—65. évi megfigyelések a Hortobágy madárvilágáról. Déri Múz. Évk. 1965. 383-396. Debrecen. Sterbetz, I. (1972): 1966—69. évi adatok a Hortobágy madárvilágáról. Déri Múz. Évk. 1969-70. 33-52. Debrecen. Szomjas, G. (1909): Jegyzetek a Hortobágyról. Aquila, 16. 306. Szomjas, G. (1911): Buteo ferox a Hortobágyon... Aquila, 18. 392-394. Szomjas, G. (1917): Madártani jegyzetek a Hortobágyról az 1916. és 1917-évekről. Aquila, 24. 273-274. Szomjas, G. (1919): Madártani hírek a Hortobágyról az 1918. évről. Aqula, 26. 110-111. Szomjas, L. (1924): Buteo ferox adatok. Aquila, 30-31. 298. Udvardy, M. (1941): A Hortobágy madárvilága. Tisia, 5. 1-79 pp. Ujvárosy, 1. (1928): Tavaszi vonulás 1925. In. Warga K.: Madárvonulási adatok Magyarországból. Aquila, 34—35. 301 Vasvári, M. (1928): A vörösnyakú lúd téli szállása állatföldrajzi megvilágításban. Aquila, 34-35.214-228.
Author's address: Dr. Gábor Kovács Nagyiván Bem apó u. 1. H-5363
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Adatok a pusztai ölyv (Buteo rufinus) 1976-1991 közötti hortobágyi előfordulásához Dr. Kovács Gábor Hortobágyi Nemzeti Park
A szerző 16 év 232 megfigyelési adata alapján foglalkozik tanulmányában a pusztai ölyvvel. Munkájában utal az 1908. és 1976. közötti hét évtized hortobágyi adataira, főként Szomjas G. és Sterbetz I. közleményei alapján. A tanulmányban ismerteti a faj évszakos mozgalmait (vonulás, átnyaralás, telelés), táplálkozásra, viselkedésre vonat kozó megfigyeléseit. Becslése szerint a Hortobágyon 1987-ig évi 10-12, 1988-tól viszont már évi 14-18 példány tartózkodott, főként a nyár végi,kora őszi két hónapban. Viszonylag új jelenség a tavasztól őszig tartó huzamos időzésük, mely 1990-ben és 1991-ben fordultelő. A fiatal egyedek aránya a 10-20%-ot nem haladja meg. A két színváltozat közül (öreg madarak) a világos változat a gyakoribb (80-85%) a vörössel szemben. Adatait táblázatos összesítés formájában közli. A pusztai ölyv havi megoszlását külön is bemutatja.
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