Journal of Avian Biology
Supplementary material
JAV-00396
Schweiger, A., Fünfstück, H.-J. and Beierkuhnlein,
C. 2014. Availability of optimal-sized prey affects
global distribution patterns of the golden eagle Aquila
chrysaetos. – J. Avian Biol. doi: 10.1111/jav.00396
Appendix 1
Table A1 Diet breadth and distance to species distribution boundary of nesting Golden Eagle
populations based on international literature accounts from the Palearctic and Nearctic region. n:
number of examined prey individuals, Nests: number of observed nests; B: diet breadth as a
measure for foraging generalism; distance: minimum distance to eagles distribution boundary.
Region
Source
n
Nests
B
distance
(-)
(km)
Palearctic (52 studies)
Norway (Fimark fjord)
Johnsen et al. (2007)
144
12
3.64
40
Norway (Finmark inland)
Johnsen et al. (2007)
325
25
2.77
272
Finland (north)
Sulkava et al. (1984)
3766
500
3.3
133
Finland (south)
Sulkava et al. (1984)
1796
50
2.7
33
Finland (south)
Sulkava et al. (1999)
1595
?
2.8
46
Finland (south)
Sulkava et al. (1999)
3387
?
4.2
130
Finland (central)
Sulkava et al. (1999)
1049
?
3.5
336
Finland (north)
Sulkava et al. (1999)
873
?
4.0
336
Sweden (Gotland)
Högström and Wiss (1992)
645
3
3.7
27
Sweden
Tjernberg (1981)
2792
105
2.9
288
Sweden
Nytröm et al. (2006)
410
23
1.9
230
Estonia
Zastrow (1946)
133
4
6.2
153
Belarus
Ivanosky (1990)
749
10
3.4
123
Scotland (south)
Marquiss et al. (1985)
302
4
3.69
21
Scotland (north-west)
Watson et al. (1992)
345
?
3.2
31
1
Scotland (Inner Hebrides N)
Watson (2010)
85
23
4.7
9
Scotland (Inner Hebrides S)
Watson (2010)
143
29
3.5
15
Scotland (Highlands N)
Watson (2010)
274
29
7.2
54
Scotland (Highlands NW)
Watson (2010)
148
38
5.9
43
Scotland (Highlands W-Centr) Watson (2010)
17
25
7.3
17
Scotland (Highlands SW)
Watson (2010)
47
16
5.4
21
Scotland (Highlands E)
Watson (2010)
161
28
2.4
92
Scotland (SW Agryll)
Watson (2010)
109
3
7.4
19
Switzerland
Stemmler (1955)
298
65
3.8
77
Switzerland (Graubünden)
Haller (1996)
249
4
3.0
131
Switzerland (Bern/Pre-Alps)
Haller (1988)
126
2
4.7
46
Austria (Kalkalpen)
Steiner (2006)
21
1
8.3
38
Germany (Allgäuer Hochalpen) present study
82
10
6.9
68
Germany (Werdenfels)
present study
384
28
7.1
52
Germany (Berchtesgaden)
present study
411
39
8.2
49
France (Pyrenees)
Clouet (1981)
114
10
11.2
1
France (Pyrenees)
Nebel et al. (1996)
28
?
5.9
1
France (Alps)
Huboux (1987)
424
17
2.1
83
France (Alps)
Huboux (1987)
198
6
5.1
18
France (Alps)
Mathieu and Choisy (1982)
109
7
3.2
24
France (Massif Central)
Austruy and Cugnasse (1981) 83
5
6.2
43
Italy (Apennines)
Magrini et al. (1987)
149
7
4.7
5
Italy (Sicily)
Seminara et al. (1987)
74
10
4.9
4
Italy (Apennines)
Noveletto and Petretti (1980) 160
5
3.4
5
Italy (Alps)
Pedrini and Sergio (2001)
195
27
5.8
16
Spain (north-east)
Fernandez (1987)
104
30
2.1
99
2
Spain (north-west)
Delibes et al. (1975)
247
3
3.9
105
Spain (central)
Delibes et al. (1975)
229
2
3.1
64
Spain (south-west)
Delibes et al. (1975)
167
3
2.0
46
Spain (south-east)
Sánchez-Zapata et al. (2010) 99
3
3.6
41
Macedonia
Grubac (1987)
85
19
3.2
30
Hungary (Zemplen-Mts.)
Janos (1998)
58
4
8.8
32
Russia (Perm-Region)
Shepel (1992)
382
9
2.59
1542
Russia (Altai-Sayan)
Karyakin et al. (2010)
372
?
7.8
566
Kazakhstan (Aral-Caspian)
Karyakin et al. (2011)
420
115
5.6
1312
Turkmenia
Varshavski (1986)
188
5
3.2
296
Mongolia
Ellis et al. (1999)
63
1
3.6
96
Alaska
Hatler (1974)
53
1
2.8
125
Alaska
Murie (1944)
690
?
1.4
367
Alaska
Ritchie and Curatolo (1982)
66
17
2.3
232
Alberta
Boag (1977)
200
2
1.4
782
Oregon
Thompson et al. (1982)
34
7
4.5
495
Montana
McGahan (1968)
980
38
2.0
631
Idaho
Kochert (1972)
1297
28
1.8
437
Idaho
Collopy (1983)
456
8
1.9
437
Washington
Knight and Erickson (1978)
311
74
4.4
348
Arizona
Eakle and Grubb (1986)
47
2
4.5
375
Nevada
Bloom and Hawks (1982)
1154
119
1.4
268
California
Carnie (1954)
503
17
5.3
12
Nearctic (15 studies)
3
California (Santa Rosa island) Collins and Latta (2009)
242
4
5.7
7
California (Santa Cruz island) Collins and Latta (2009)
181
6
2.1
5
New Mexico
993
41
2.1
300
Mollhagen et al. (1972)
4
Study site description for the Bavarian Golden Eagles
In our study on the feeding behaviour of breeding Golden Eagles in the Bavarian Alps (Southern
Germany), we examined three subpopulations located in the very eastern parts (Berchtesgaden), the
central parts (Werdenfels) and the western-most parts (Allgäuer Hochalpen) of Bavaria over a 10year period (1998-2008). All three study sites, each covering an area of about 1400 km², are
dominated by calcareous parent material. Altitude varies between 600 and 2900 m a.s.l. On
mountain slopes, forests are characterized by coniferous trees (mainly Norway spruce, Picea abies).
The tree line ranges between 1700 and 1900 m a.s.l. Above the tree line, the vegetation is
dominated by alpine meadows. Mean annual temperature varies between 5 to 7°C in the valleys and
0 to -2°C in the summit regions. Annual precipitation ranges from 1500 up to 2600 mm (Bay.
StMLU 2001, Bay. StMUGV 2007, LfU 2007).
Prey collection and analyses for the Bavarian Golden Eagles
The diets of nesting eagles were determined for the three Bavarian populations by analysing food
remains and pellets from N = 77 nests and their close vicinity, with 10 nests in the Allgäuer
Hochalpen, 28 nests in Werdenfels and 39 nests in Berchtesgaden. Nests with recorded breeding
activity were sampled after fledglings left the nests (mainly between August and October 19982008) or breeding was abandoned. In order to get a complete picture of the foraged prey, the
uppermost layer was removed from the nests and checked for small prey remains such as claws or
skin from small mammals or birds (cf. Ellis et al. 1999). Prey remains were determined to the
lowest possible taxonomic level by considering the age and sex of prey items by using reference
collections and literature (e.g. Boye 1981, März 1987). For each prey species, the minimum number
of foraged individuals was determined by considering side of the body, degree of ossification and
grade of bone weathering (cf. Sulkava et al. 1999). Based on this information, a total of 877 preyed
5
individuals from 68 species could be determined for the study period of 10 years (1998-2008, see
Tab. A.2). However, these records for foraged individuals have to be seen as minimum numbers.
The number of prey remains within the observed nests might be biased by different intensities of
prey removal by scavengers or by different degree of cleanliness observed by the adult eagles.
Biomass was estimated for each foraged individual from the literature (e.g. Bauer et al. 2005,
Niethammer and Krapp 1968, 1978, 1990). As the living biomass especially of large prey, such as
ungulates is not fully usable for the eagles (e.g. bones), biomass values from the literature were
corrected to prevent overestimating the prey weight (cf. Högström and Wiss 1992).
Table A2: Prey species of Bavarian Golden Eagles during the nestling period between 1998 and
2008 within the three study sites Allgäuer Hochalpen (AH, 10 nests), Werdenfels (WF, 28 nests)
and Berchtesgaden (BG, 39 nests). Depicted is the number of identified prey individuals per study
site (* = determined individuals were almost unexceptional juveniles > 1 year).
Prey species
AH
WF
BG
Total
13
90
86
189
1
1
3
2
6
Chamois*
Rupicapra rupicapra
Ibex
Capra ibex
Domestic sheep
Ovis ammon f. domestica
Red deer
Cervus elaphus
2
1
3
Roe deer
Capreolus capreolus
3
18
21
Red fox
Vulpes vulpes
27
29
60
Badger
Meles meles
1
1
Beech marten
Martes foina
2
2
4
Pine marten
Martes martes
1
3
4
Marten sp.
Martes sp.
3
4
9
1
4
2
6
Stoat
Mustela erminea
2
Domestic cat
Felis sylvestris f. catus
Mountian hare
Lepus timidus
European hare
Lepus europaeus
Hare sp.
Lepus sp.
Domestic hare
Leporidae sp.
1
1
Hedgehog
Erinaceus europaeus
1
1
European mole
Talpa europaea
Shrew sp.
Soricidae sp.
Yellow-necked mouse
Apodemus flavicollis
Long-tailed mouse sp.
Muridae sp.
2
Common vole
Microtus arvensis
3
1
4
Brown vole
Microtus agrestis
2
1
3
Vole sp.
Microtus sp.
3
3
Alpine marmot
Marmota marmota
16
10
18
44
Red squirrel
Sciurus vulgaris
4
25
12
41
Edible dormouse
Glis glis
1
1
Mallard
Anas platyrhynchos
2
2
Common buzzard
Buteo buteo
4
10
Goshawk
Accipites gentilis
1
1
Sparrow hawk
Accipiter nisus
1
1
Kestrel
Falco tinnunculus
12
22
Peregrine
Falco peregrinus
2
2
Woodcock
Scolopax rusticola
1
6
Yellow-legged gull
Larus michahellis
1
1
Eurasian jay
Garrulus glandarius
4
5
6
2
3
5
1
1
38
21
65
4
4
8
14
23
39
1
1
2
1
3
5
7
5
1
3
5
1
1
2
7
Eurasian nutcracker
Nucifraga caryocatactes
2
2
Balck-billed magpie
Pica pica
1
1
Alpine chough
Pyrrhocorax pyrrhocorax
1
1
3
5
Carrion crow
Corvus corone
1
1
7
9
Common raven
Corus corax
1
4
12
17
Common cuckoo
Cuculus canorus
1
1
Tawny owl
Strix aluco
4
4
Boreal owl
Aegolius funereus
2
2
Pygmy owl
Glaucidium passerinum
Owl sp.
Strigidae sp.
1
1
Black woodpecker
Dendrocopus martius
1
1
Great spotted woodpecker
Dendrocopus major
3
1
4
Common wood pigeon
Columba palumbus
1
1
2
Feral pigeon
Columba livia f. domestica
1
2
Pigeon sp.
Columba sp.
5
4
9
Capercaillie
Tetrao urogallus
1
14
15
30
Black grouse
Tetrao tetrix
11
47
52
110
Rock ptarmigan
Lagopus muta
4
4
9
17
Hazel grouse
Tetrastes bonasia
8
1
9
Grouse sp.
Tetraoninae sp.
3
2
5
Gamefowl
Galliformes sp.
3
3
Barn fowl
Gallus gallus f. domesticus
Sky lark
Alauda arvensis
Blackbird
Turdus merula
Ring ouzel
Turdus torquatus
Song thrush
Turdus philomelos
1
1
1
1
1
1
1
1
1
1
2
7
2
9
4
3
8
8
Mistel thrush
Turdus viscivorus
Thrush sp.
Turdus sp.
Black redstart
Phoenicurus ochruros
1
1
Snowfinch
Montifringilla nivalis
1
1
Chaffinch
Fringilla coeleps
Red crossbill
Loxia curvirostra
1
1
Citril finch
Serinus citrinella
2
2
Dunnock
Prunella modularis
1
1
Lizard sp.
Lacerta sp.
Slowworm
Anguis agillis
2
Common frog
Rana temporaria
1
Sterlet
Acipenser ruthenus
Dung beetle sp.
Geotrupidae sp.
Weevil sp.
Curcurlionidae sp.
Beetle sp.
Coleoptera sp.
Total
14
4
18
2
2
1
1
2
2
1
2
1
2
1
1
1
2
2
2
3
3
4
10
82
384
411
877
9
Additional references
Austruy, J. and Cugnasse, J. 1981. L'Aigle Royal Aquila chrysaetos dans le Massif Central. –
Nos Oiseaux 36: 133–142.
Bauer, H. G., Bezzel, E. and Fiedler, W. (eds.) 2005. Das Kompendium der Vögel
Mitteleuropas. Vol. 1 and 2. – Aula.
Bayerisches Staatsministerium für Landesentwicklung und Umweltfragen (BayStMLU) 2001.
Nationalparkplan Berchtesgaden. – Bay. StMLU.
Bayerisches Staatsministerium für Umwelt, Gesundheit und Verbraucherschutz (Bay.
StMUGV) 2007. ABSP-Band, Arten-und Biotopschutzprogramm. Landkreis GarmischPartenkirchen. Vol. 2. – Landesamt für Umwelt.
Bloom, P. H. and Hawks, S. J. 1982. Food habits of nesting Golden Eagles in northeast
California and northwest Nevada. – Raptor Research 16: 110–115.
Boag, D. A. 1977. Summer food habits of Golden Eagles in southwestern Alberta. – Canadian
Field Naturalist 91: 296–298.
Boye, P. 1981. Heimische Säugetiere. – Deutscher Jugendbund für Naturbeobachtungen.
Carnie, S. K. 1954. Food habits of Golden Eagles in the coast ranges of California. – Condor
56: 3–12.
Clouet, M. 1981. L'Aigle Royal Aquila chrysaetos dans les Pyrénées Francaises. Resultats de
5 ans d'observations. – L'Oiseau et R.O.F 51: 89–100.
Collopy, M. W. 1983. A comparison of direct observations and collections of prey remains in
determining the diet of Golden Eagle. – Journal of Wildlife Management 47: 360–368.
Eakle, W. L. and Grubb, T. G. 1986. Prey remains from Golden Eagles Nests in Central
Arizona. – Western Birds 17: 87–89.
Fernandez, C. 1987. Seasonal variation in the feeding habits of a pair of golden eagles in
Navarra. – In: Michel, S. (ed), L'Aigle Royal en Europe. Actes du Premier Colloque
International, pp. 107–117.
Hatler, D. F. 1974. Foods at a Golden Eagle nest in central Alaska. – Condor 76: 356–357.
Huboux, R. 1987. Contribtion a une meilleure connaissance du – In: Michel, S. (ed), L'Aigle
Royal en Europe. Actes du Premier Colloque International. pp. 118–123.
Ivanosky, V. V. 1990. Birds of prey and ornithological monitoring (in Russian). –
Communication of the Baltic Commission for Study of Bird Migration 22: 92–101.
Janos, B. 1998. On the occurrence and foraging of the Golden Eagle (Aquila chrysatos) in the
Zemplén-Mountains. – Ornis Hungarica 8: 211–214.
Johnsen, T. V., Systad, G. H., Jacobsen, K. O., Nygård, T. and Bustness, J. O. 2007. The
occurrence of reindeer claves in the diet of nesting Golden Eagles in FInmark, northern
Norway. – Ornis Fennica 84: 112–118.
Karyakin, I. V., Nikolenko, E. G., Barashkova, A. N., Smelansky, I. E., Konovalov, L. I.,
Grabovskiy, M. A., Vazhov, S. V., Bekmansurov, R. H. 2010. Golden Eagle in the
Altai-Sayan Region, Russia. – Raptors Conservation 18: 82–152.
Karyakin, I. V., Kovalenco, A. V., Levin, A. S. and Pazhenkov, A. S. 2011. Eagles of the
Aral-Caspian Region, Kazakhstan. – Raptors Conservation 22: 92–152.
Knight, R. L. and Erickson, A. W. 1978. Marmots as a food source of Golden Eagles along
the Columbia River. – Murrelet 59: 28–30.
Kochert, M. N. 1972. Population status and chemical contamination in Golden Eagles in
southwestern Idaho. – University of Idaho, M.Sc thesis.
Landesamt für Umwelt (LfU) 2007. Standard-Datenbogen 8528-401, Naturschutzgebiet
„Allgäuer Hochalpen. – LfU.
Magrini, M., Ragni, B. and Amertano, L. 1987. L'Aigle Royal dans la partie centrale des
Appennins. – In: Michel, S. (ed), L'Aigle Royal en Europe. Actes du Premier Colloque
International. pp. 29–32.
Marquiss, M., Ratcliffe, D. A. and Roxburgh, R. 1985. The Numbers, Breeding Success and
Diet of Golden Eagles in Southern Scotland in Relation to Changes in Land Use. –
Biological Conservation 34: 121–140.
März, R. 1987. Gewöll- und Rupfungskunde. 3., neu von Konrad Banz bearbeitete Auflage. –
Akademie-Verlag.
McGahan, J. 1968. Ecology of the Golden Eagle. – Auk 85: 1–12.
Mollhagen, T. R., Wiley, R. W. and Packard, R. L. 1972. Prey remains in Golden Eagle nests:
Texas and New Mexico. – Journal of Wildlife Management 36: 784–792.
Murie, A. 1944. The Wolves of Mt. McKinley. (Golden Eagle-Chapter 8). – US Fauna series
No 5.
Nebel, D., Duquesne, A. and Geoffroy, J. 1996. L’Aigle royal Aquila chrysaetos dans la
Réserve Domaniale du Mont Vallier (Ariège) 1987-1995. – Alauda 64: 179–186.
Niethammer, J. and Krapp, F. (eds) 1968. Handbuch der Säugetiere Europas; Band 2/II:
Paarhufer-Artiodactyla (Suidae, Cervidae, Bovidae). – Aula.
Niethammer, J. and Krapp, F. (eds) 1978. Handbuch der Säugetiere Europas; Band 1:
Rodentia I (Sciuridae, Castoridae, Gliridae, Muridae). – Akademische
Verlagsgesellschaft.
Niethammer, J. and Krapp, F. (eds) 1990. Handbuch der Säugetiere Europas; Band 3/I:
Insektenfresser – Insectivora, Herrentiere – Primates. – Aula.
Noveletto, A. and Petretti, F. 1980. Ecologia dell' Aquila Reale negli Appennini. – Rivista
Italiana di Ornitolgia 50: 127–142.
Ritchie, R. J. and Curatolo, J. A. 1982. Notes on Golden Eagle productivity and nest site
characterisation, Porcupine River, Alaska, 1979-1982. – Raptor Research 16: 13–127.
Sánchez-Zapata, J. A., Eguía, S., Blázquez, M., Moleón, M. and Botella, F. 2010. Unexpected
role of ungulate carcasses in the diet of Golden Eagles Aquila chrysaetos in
Mediterrenean Mountains. – Bird Study 57: 352–360.
Seminara, S., Giarratana, S. and Favara, R. 1987. L'Aigle Royal en Sicile. . – In: Michel, S.
(ed), L'Aigle Royal en Europe. Actes du Premier Colloque International. pp. 33–36.
Shepel, A.I. 1992. Raptors and owls of Perm region. – Izd-vo Irkut, un-ta.
Stemmler, C. 1955. Der Steinadler in den Schweizer Alpen. – Selbstverlag.
Thompson, P. S., Johnstone, R. S. and Littlefield, C. D. 1982. Nesting history of Golden
Eagles in Malheur Lakes Basin, southeastern Oregon. – Raptor Research 16: 116–122.
Tjernberg, M. 1981. Diet of the Golden Eagle Aquila chrysaetos during the breeding season
in Sweden. – Holarctic Ecology 4: 12–19.
Varshavski, B. S. 1986. Feeding of Aquila chrysaetos in southwestern Ust-urt (in Russian) –
Ornitotlogija 9: 146–149.
Watson, J., Leitch, A. F. and Broad, R. A. 1992. The diet of the Sea Eagle Haliaeetus
albicilla and the Golden Eagle Aquila chrysaetos in western Scotland. – Ibis 134: 27–
31.
Zastrow, M. 1946. Om Kungsörnens Aquila chrysaetos ut bredning och biologi i Estland. –
Vår Fågelvärld 5: 64–80.