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14. Colour ringing of the Spotted Eagles (Aquila pomarina, Aquila clanga and their hybrids) in Europe – a review. By Dravecký M, Sellis U, Bergmanis U, Dombrovski V, Lontkowski J, Maciorowski G, Maderič B, Meyburg B-U, Mizera T, Stój M, Treinys R & Wójciak J (2008)

Full text available:
http://www.raptor-research.de/pdfs/a_rp ... E_2008.pdf

Published in: Slovak Raptor Journal 2: 37–52

Abstract: During the years 2000–2008 1377 Spotted Eagles (SE) (Aquila pomarina, Aquila clanga and their hybrids) have been colour ringed in Europe. Out of these, 1303 (94.6 %) were young birds and 74 (5.4 %) were adults. Out of the total, 1290 (93.7 %) were the Aquila pomarina Lesser Spotted Eagles (LSE) – 1229 (95.3 %) young and 61 (4.7 %) adults, 50 (3.6 %) were the Aquila clanga Greater Spotted Eagles (GSE) – 44 (88.0 %) young and 6 (12.0 %) adults and 37 (2.7 %) were the Aquila pomarina × Aquila clanga hybrids (LSE×GSE) – 30 (81.1 %) young and 7 (18.9 %) adults. With respect to the individual European countries the following SE species and numbers were ringed: Slovakia 636 (46.2 %), Poland 333 (24.2 %), Estonia 153 (11.1 %), Germany 116 (8.4 %), Lithuania 68 (4.9 %), Latvia 45 (3.3 %) and Belarus 26 (1.9 %). In the article authors presents a review on Spotted Eagle colour ringing programmes running in individual European countries.
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15. Cainism, nestling management in Germany in 2004–2007 and satellite tracking of juveniles in the Lesser Spotted Eagle (Aquila pomarina). By Meyburg B-U, Graszynski K, Langgemach T, Sömmer P & Bergmanis U (2008)

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http://www.raptor-research.de/pdfs/a_rp ... ainism.pdf

Published in: Slovak Raptor Journal, 2: 53–72.

Summary in German:

ZUSAMMENFASSUNG

Der Schreiadler gehört zu den Arten mit obligatem Kainismus, d.h. nur sehr selten fliegen zwei Jungadler natürlicherweise aus einem Horst aus, obwohl sehr häufig zwei Küken schlüpfen.

Der Brutbestand in Deutschland befindet sich am westlichen Rand des Verbreitungsgebietes und ist rückläufig. Zwischen 1993 und 2007 wurde ein Rückgang um 23% festgestellt. Mit dem lokalen Aussterben ist zu rechnen. Daher wurde seit 2004 Jungvogelmanagement im Bundesland Brandenburg als zusätzliche Schutzmassnahme durchgeführt, um durch menschliche Intervention den Tod der zweitgeschlüpften jungen Schreiadler (Abels) zu verhindern, in Ergänzung zu anderen Methoden, wie z. B. Horstschutz, Habitatschutz, gesetzlichen Regelungen usw. Zusätzlich wurden 2007 erstmals auch Abels aus Lettland in deutsche Horste eingesetzt.

Die gemanagten Brutpaare, deren Horste bestiegen wurden, waren durchschnittlich erfolgreicher als die ungemanagten Paare, deren Nester nicht bestiegen wurden. Der Bruterfolg der in Brandenburg anwesenden Paare einschließlich der Nichtbrüter wurde 2007 um 57 % dank des Jungvogelmanagements gesteigert. Bei den gemanagten Paaren gab es eine Steigerung um 67 %. Ein negativer Einfluss auf den Bruterfolg konnte durch die Horstbesteigungen nicht festgestellt werden.

Das Verhalten von sechs Jungadlern wurde 2007 mit Hilfe der Satelliten-Telemetrie untersucht. Dabei konnte festgestellt werden, dass die Abels genau so gut wie die erstgeschlüpften Jungvögel (Kains) zogen und genauso überlebensfähig sind. Die von Lettland nach Deutschland translozierten Jungadler zogen in zwei von drei Fällen auf derselben Route wie deutsche Schreiadler zum Bosphorus. Ein in Deutschland ausgeflogener lettischer Abel konnte bis Sambia telemetriert werden, wo viele Schreiadler überwintern. Ein deutscher Abel überwinterte über sechs Monate lang nördlich des Äquators im Sudan und in angrenzenden Ländern und begann seinen Heimzug am 27. April 2008.
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16. Autumn migration of Lesser Spotted Eagle Aquila pomarina in the Strait of Gibraltar: accidental or regular? By Onrubia A., Muñoz A.-R., Arroyo G.M., Ramírez J., de la Cruz A., Barrios L., Meyburg B.-U., Meyburg C. & Langgemach T. (2011)

Full text available as PDF:
http://www.raptor-research.de/pdfs/a_rp ... raltar.pdf

Published in: Ardea 99: 113-116

Key words: Lesser Spotted Eagle, Aquila pomarina, migration, Strait of Gibraltar
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17. Satellite tracking of two Lesser Spotted Eagles, Aquila pomarina, migrating from Namibia. By Meyburg, B.-U., D.H. Ellis, C. Meyburg, J.M. Mendelsohn & W. Scheller (2001)

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http://www.raptor-research.de/pdfs/a_sp100p/a_sp121.pdf

Published in: Ostrich 72: 35-40 (In English with summaries in English and German)

Summary:

One immature and one subadult Lesser Spotted Eagle, Aquila pomarina, were followed by satellite telemetry from their nonbreeding areas in Namibia. Both birds were fitted with transmitters (PTTs) in February 1994 and tracked, the immature for six months and three weeks, the subadult for eight months and two weeks, over distances of 10 084 and 16 773 km, respectively. During their time in Namibia both birds’ movements were in response to good local rainfall. The immature eagle left Namibia at the end of February, the subadult at the end of March. They flew to their respective summer quarters in Hungary and the Ukraine, arriving there 2.5 and 1.5 months later than the breeding adults. The immature eagle took over two months longer on the homeward journey than a breeding male followed by telemetry in a previous study. On returning, the immature eagle followed the narrow flightpath through Africa used by other Lesser Spotted Eagles on their outward migration. It reached this corridor, which runs roughly between longitudes 31° and 36° East from Suez to Lake Tanganyika, veering from the shortest route in a direction east-northeast through Angola and Zambia to the southern end of Lake Tanganyika. The route taken by the subadult bird on its return migration differed markedly from that of all Lesser Spotted Eagles tracked to date, running further west through the Democratic Republic of Congo where, level with the equator, it flew over the eastern rainforest of that country. The outward migration, however, followed the same corridor and coincided in time with the migration of adults. [A German translation of the abstract is provided on p. 40]
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18. Satellite-tracked Lesser Spotted Eagle avoids crossing water at the Gulf of Suez. By Meyburg, B.-U., J. Matthes & C. Meyburg (2002)

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http://www.raptor-research.de/pdfs/a_sp100p/a_sp122.pdf

Published in: British Birds 95: 372-376 (with 5 colour photos and two maps)

ABSTRACT
To date, most of the Lesser Spotted Eagles Aquila pomarina that we have tracked by satellite telemetry migrated in autumn along a direct route from Israel to Africa, via Suez (Egypt). In both 1997 and 1998, however, one adult female was tracked to the southern tip of the Sinai Peninsula, and from there flew north again to Suez. Only one other adult eagle is known to have flown south over the Sinai Peninsula, but from there crossed the Gulf of Suez.The possible reasons for this behaviour, involving a 500-km detour and a flight of about three and a half days, are discussed.
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19. Migration, wintering and breeding of a Lesser Spotted Eagle (Aquila pomarina) from Slovakia tracked by Satellite. By Meyburg, B.-U., C. Meyburg, T. Belka, O. Sreibr & J. Vrana (2004)

Full text as PDF available here:
http://www.raptor-research.de/pdfs/a_sp100p/a_sp125.pdf

Published in: Journal of Ornithology 145: 1-7. (In English with abstracts in English and German)

Keywords: Aquila pomarina, migration, nest site, fidelity, satellite telemetry, wintering

Abstract:
In northern Slovakia an adult male Lesser Spotted Eagle (Aquila pomarina) occupied the same nest site for 11 years running (1992–2002), where it was ringed and fitted with two satellite transmitters. In six of these years it successfully reared a young. In 1994 and 2000–2002 its behaviour during migration could be followed in detail by means of satellite telemetry. The eagle took the known route for this species to South Africa. In 2001, it spent 43% of the year at its breeding
site, 33% in its winter quarters, the remaining 24% being spent on migration. In three cases the autumn migration took 40, 48 and 61 days respectively. In two cases the spring migration took 49 days. All five recorded autumn and spring migrations averaged a daily flight distance of 178 km. In spring the daily flight distance was in general slightly greater than in autumn. The longest was recorded from 30 March to 2 April 2001, between Uganda and the Red Sea, during which the bird covered a total of 1,650 km, averaging 412 km per day. In 2001, the spring migration from the wintering grounds was 2 weeks later than in 2002. The wintering grounds, where in 2 years the bird spent around 3.5 months, covering at least 1,666 and 2,269 km, respectively, comprised a large part of Zimbabwe together with the Kruger National Park in South Africa and neighbouring parts of Mozambique. The annual journeys flown, including movements around the wintering grounds, amounted in 2000-2001 to at least 20,396 km and in 2001-2002 to 19,041 km. Except during its crossing of the Sahara, the eagle must have taken food on nearly all its days of migration.
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20. Why do female Lesser Spotted Eagles (Aquila pomarina) visit strange nests remote from their own? Meyburg, B.-U., C. Meyburg, F. Franck-Neumann (2007)

Full text as PDF available here:
http://www.raptor-research.de/pdfs/a_sp100p/a_sp132.pdf

Published in: Journal of Ornithology 148: 157-166 (Dt. Zusammenf.: Weshalb besuchen Schreiadler-Weibchen (Aquila pomarina) weit entfernte fremde Nester ?)

SUMMARY

There is very little confirmed information on the social organisation of breeding Lesser Spotted Eagle populations, the turnover rate of adults and their nest site and partner fidelity. According to established knowledge, however, breeding individuals are territorial and defend at least the immediate vicinity of the nest site against their own species. It was further thought that females rearing young, as with the females of other raptor species, remain within a radius of only a few kilometres of their eyrie. Using GPS satellite telemetry and DNA microsatellite analysis (DNA STR typing) we were able to disprove this prevailing hypothesis. A satellite tracked female flew over 50 km away from her eyrie (D) in at least two different directions and visited at least one other occupied eyrie (T). It was also established that at least two strange females arrived at her eyrie, containing young, from as far away as 57 km, and probably remained there for some considerable time. The pool of alleles represented at the different loci analysed, as well as the distribution of theses alleles between the individuals, excludes the possibility that theses females could be sisters or even half-sisters. Visits of strange eagles at this eyrie were also confirmed by direct observation. It can therefore be assumed that males only exhibit territorial behaviour towards their own sex and not towards strange females and that females do not exhibit territorial behaviour towards other females; but all these assumptions must be confirmed by further studies. For the first time it could be proved by means of microsatellite analysis that almost all females studied used the same breeding site in two consecutive years. The longest established period for both partners of a pair remaining at the same breeding site was 3 consecutive years.
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21. Annual cycle, timing and speed of migration of a pair of Lesser Spotted Eagles (Aquila pomarina) – a study by means of satellite telemetry. By Meyburg, B.-U. & C. Meyburg (2009)

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http://www.raptor-research.de/pdfs/a_sp ... iadler.pdf

Published in: Populationsökologie Greifvogel- und Eulenarten / Population Ecology of Raptors and Owls , Bd. 6, 63-85

Summary in German:
http://www.raptor-research.de/summary/a ... ummary.pdf
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22. Habitats used by Lesser Spotted Eagles (Aquila pomarina) during migration and wintering as revealed by Satellite tracking and remote sensing. By Gerkmann, B. & B.-U. Meyburg (2009)

Full text available as PDF:
http://www.raptor-research.de/pdfs/a_sp ... iadler.pdf

Published in: Populationsökologie Greifvogel- und Eulenarten / Population Ecology of Raptors and Owls , Bd. 6, 87–102

Summary in German:
http://www.raptor-research.de/summary/a ... ummary.pdf
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23. The Lesser Spotted Eagle Aquila pomarina in the North Caucasus, Russian Federation: taxonomic status, genetic diversity, breeding density and nest site characteristics. By Ü. Väli; V.P. Belik; I. G. Babkin (2009)

Full text available as PDF:
https://www.etis.ee/File/DownloadPublic ... tion%2Fpdf

Published in: Sandgrouse, 31.2009, p. 122-127

Summary:

We studied the Lesser Spotted Eagle population in a 55 km2 study area near Kislovodsk, North Caucasus, in July 2007. Birds were observed on ten breeding territories while nests, distributed unevenly in the landscape in forested river valleys, were found and described for eight territories. Productivity in 2007 was 0.71 nestlings per occupied nest. The results of our mitochondrial DNA analysis indicate that the Caucasus region is inhabited by the same subspecies as occurs elsewhere in Europe. However, the genetic diversity within the Caucasian population was much higher than that of more northern European populations, suggesting that the Caucasian population is relatively old and not been subject to historical or recent ‘bottlenecks’.
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24. The effects of habitat quality and female size on the productivity of the lesser spotted eagle Aquila pomarina in the light of the alternative prey hypothesis. By A. Lohmus, Ü. Väli (2004)

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https://www.etis.ee/File/DownloadPublic ... tion%2Fpdf

Published in: Journal of Avian Biology 35.2004,5. p 455-464

Abstract:
Habitat quality is an important but insufficiently understood concept in ecology and conservation biology, due to geographic and temporal variation as well as interaction with individual quality. In 1994-2002, we studied the Estonian population of the lesser spotted eagle Aquila pomarina in order to (1) explore the relative contributions of habitat and female size in reproductive success; (2) check for a switch to alternative prey in vole-poor years and the relevant variation in annual habitat quality as confirmed in the common buzzard Buteo buteo in the same area. We measured five landscape variables, the number of neighbouring conspecifics and the relative size of the female according to large moulted feathers in 77 nesting territories, and related this to the eagles’ productivity in vole-rich and vole-poor years. Nesting lesser spotted eagles benefited from heterogeneous landscapes and suffered from the neighbourhood of conspecifics. There was no evidence that different-sized females used different habitats. In general, female size was positively related to productivity in vole-poor but not vole-rich years, but in the presence of competitors, large size appeared to be disadvantageous. The mean annual productivity of the eagle was well correlated with that of the buzzard, both having peaks after every three years. In contrast to the buzzard, the share of voles in the eagle’s diet and its habitat quality did not differ significantly between good and poor years. We concluded that despite a superficial ecological similarity to the buzzard, the lesser spotted eagle did not behave as predicted by the alternative prey hypothesis, but the study confirmed that annual variation in prey utilization and relative habitat quality are parts of the same functional response. Non-switching to alternative prey may be related to a historical foraging strategy, used by the eagles before they spread to agricultural landscapes, since the current effects of body size strongly suggested food shortage in vole-poor years
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25. Sex ratio of Lesser Spotted Eagle Aquila pomarina nestlings in good and poor breeding years. By Ülo Väli (2004)

Full text available as PDF:
https://www.etis.ee/File/DownloadPublic ... tion%2Fpdf

Free access Taylor and Francis online: http://www.tandfonline.com/doi/abs/10.1 ... 0409461352

Published in: Bird Study 51.2004, 2, p. 189-191

Capsule:
The ratio was female-biased in good years and male-biased in poor years, but did not differ from parity in the long term.
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26. Numbers and population dynamics of the Lesser Spotted Eagle Aquila pomarina in Estonia. By Lõhmus, A.; Väli, Ü. (2001)

Full text available as PDF:
https://www.etis.ee/File/DownloadPublic ... tion%2Fpdf

Published in: Acta Ornithoecologica. 4.2001,2 p. 291-295

Abstract:
In the 1990s the numbers of the Lesser Spotted Eagle were studied on sample plots with a total area of 4385 km2. The average annual density (territories per 100 km2) was 0-0.45 in northwestern Estonia and the western archipelago, 0.96-1.51 in western and south-western Estonia, 1.49-1.55 in northern and north-eastern Estonia, and 2.32-2.52 in eastern and south eastern Estonia. The total Estonian population was estimated at 480-600 territorial pairs in 1991-1997. The numbers seem higher than 100 years ago, despite the decline in the first half of the 20th and local declines in the 1960s-1980s. The main reason for the first decline was probably persecution. In the middle of the 20th the species was restricted to natural landscapes, but started to inhabit arable lands in the 1960s. These lands provide enough food for normal recruitment as the average productivity in Estonia was 0.52 young per occupied territory annually in 198l-l997. The probable reasons for habitat switch are briefly discussed.

Key words: Aquila pomarina, density, population dynamics, ecology, productivity, Estonia.
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27. Satellite Tracking of Raptors – How PTTs Changed Our Lives. By Bernd-U. Meyburg & Christiane Meyburg

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http://www.raptor-research.de/pdfs/a_sp ... aptors.pdf
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28. 8th Conference of the European Ornithologists’ Union 27–30 August 2011, Riga: Programme and Abstracts (2011)

Page 61:
Experience With The Hacking Method For Support Of The Lesser Spotted Eagle (Aquila Pomarina) Population In Germany
Presented by Uģis Bergmanis
Bernd-U. Meyburg, Uģis Bergmanis, Torsten Langgemach, Kai Graszynski, Arno Hinz, Ingo Börner, Paul Sömmer, Christiane Meyburg
(Posters in German and English linked here: viewtopic.php?p=133603#p133603)

Page 394
Productivity and offspring sex ratio in the Lesser Spotted Eagle: does time matter?
Presented by Ülo Väli
Ülo Väli

PDF available here:
http://eounion.org/wp-content/uploads/2 ... tracts.pdf
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29. Studies of less familiar birds - Lesser Spotted Eagle. By B.-U. Meyburg (1973)

Full text available as PDF - kindly made available for the LK Forum by Prof. Dr. Meyburg
http://www.looduskalender.ee/logos/Less ... rbirds.pdf

Published in British Birds 66.1973,10
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30. Lesser Spotted Eagle by Bernd-U. Meyburg (Czechoslovakia & Germany)

Chapter in a book, PDF kindly made available for the LK-Forum by Prof. Dr. Meyburg:
http://www.looduskalender.ee/logos/The- ... tchers.pdf

Published in: The Eagle Watchers. Ed. by Ruth E. Tingay and Todd E. Katzner (2010)
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31. Age at first breeding, philopatry, longevity and causes of mortality in the Lesser Spotted Eagle Aquila pomarina by Bernd-Ulrich Meyburg, Tomas Belka, Stefan Danko, Janusz Wójciak, Günter Heise, Torsten Blohm und Hinrich Matthes (2005)
Geschlechtsreife, Ansiedlungsentfernung, Alter und Todesursachen beim Schreiadler Aquila pomarina

Full text available as PDF:
http://www.raptor-research.de/pdfs/a_rp ... p711_e.pdf

Published in: Limicola, Zeitschrift für Feldornithologie, Band 19, Heft 3, 2005, S. 153-179

German original article: http://www.b-u-meyburg.de/pdfs/a_rp700p/a_rp711.pdf


Age at first breeding, philopatry, longevity and causes of mortality in the Lesser Spotted Eagle Aquila pomarina

To date there are no definite conclusions as to the age at which the Lesser Spotted Eagle Aquila pomarina reaches sexual maturity. In the course of a long-term study we were able to trap 4- and 5-year-old ringed birds in Germany and Slovakia. A 4-year-old female and a 5-year-old male reproduced; another 4-year-old male had paired up and occupied a territory but did not breed (Tab. 1).
The 4-year-old female and 5-year-old male were already in full adult plumage, whereas the 4 year old male still had a yellow nape patch as well as many fresh juvenile type feathers on various parts of the body, including typical juvenile plumage in the rump area. From this it appears that male Lesser Spotted Eagles attain full adult plumage and sexual maturity one year later than female birds.
Both male birds had settled markedly closer (4.7 and 8 km) to their birthplace than two females (59 and 90 km) (Tab. 1). 18 adult birds reached an average age of 10.5 years (Tab. 2). Taking this and the average breeding success of the Lesser Spotted Eagle into account, it can be calculated that sexually mature females produce about 4.5 and males approx. 3.9 fledged young during their lifespan.
Shooting was by far the commonest cause of mortality of Lesser Spotted Eagles at least 11 of 30 ringed individuals (Tab. 2, 3 and 4).
Some 1 and 2-year-old ringed Lesser Spotted Eagles returned to the breeding area during the breeding season. On the other hand, a 2-year-old eagle caught in August had remained in the wintering area in Zambia (Tab. 4). The prevailing behaviour is still unclear.
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32. European Union Species Action Plan for Lesser Spotted Eagle (Aquila pomarina) 1997

Full text of this document available online as PDF:
http://ec.europa.eu/environment/nature/ ... marina.pdf
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33. Predicted and observed migration speed in Lesser Spotted Eagle Aquila Pomarina. By Anders Hedenström (1997)

Full text of this document online available at:
http://www.avibirds.com/pdf/S/Schreeuwarend6.pdf

Published in: Ardea 85: 29-36.

Abstract:
Satellite telemetry has recently been used to track the migration of eight Lesser Spotted Eagles Aquila pomarina and one Spotted Eagle A. clanga (Meyburg et al. 1993, 1995a & b). I used aerodynamic theory to predict the overall migration speed in these eagles using either thermal soaring or flapping flight. Using flapping flight the predicted migration speed is maximum 95 km day-l and in thermal soaring the predicted speed varies largely depending on the assumptions on energy deposition rate and climb rate in thermals. The observed mean migration speed was 139 km day-l for the Lesser Spotted Eagle and 150 km day-I for the Spotted Eagle. These speeds are significantly higher than had the birds migrated by flapping flight, and so soaring flight must be involved to a large extent. There were some indications that the prediction in best agreement with the observations will be found for an energy accumulation rate Pde = 1 X BMR and a climb rate Vc = 1- 1.5 m S·l. However, at present these Pconclusions are provisional and the predictions may be fraud with uncertainties. I discuss which factors have a major influence on the migration speed and they include fuel accumulation rate in the field, climb rate in thermals, limitations on thermal time and energy cost of gliding flight. Future studies of migration speed using satellite telemetry should focus on these factors.
Key words: Aquila clanga - soaring migration - satellite tracking - aerodynamics
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