Diet of the Red-backed Shrike was analysed from collars in nestlings, pellets and prey remains in larders. All the material was collected from the same territories in Western Poland. A total of 2855 prey items were identified from all samples. Insects, mainly Coleoptera, Hymenoptera and Orthoptera constituted 98.9% of all prey items identified. To determine diet and predict impact of food sources on Red-backed Shrike populations, three methods should be used together (pellet content analyses, collar sampling and analysing larders). Our findings suggest that pellet content analyses is an easy and non-invasive method for estimating prey diversity and frequency index. Collars are necessary to determine nestling diets. Analyses of prey remains in larders should be used to find large prey, handled before eating. In more advanced geographical analysis of the content of shrike diet, we suggested to pool together data obtained by different methods from the same place, and/or carefully assign methods of diet analyses.
REFERENCES
J. Arcas
1998. [Diet of Red-backed Shrikes (Lanius collurio L.) in Orense (Galicia, NW Spain)]. Ardeola 45: 69–71. Google Scholar
O. Cajander
1929. [Foraging methods of Red-backed Shrike (Lanius collurio L.)]. Ornis Fenn. 6: 6–11. Google Scholar
M. C. Calver
,
R. D. Wooller
1982. A technique for assessing the taxa, length, dry weight and energy content of the arthropod prey of birds. Austr. Wildl. Res. 9: 293–301. Google Scholar
S. Cramp
,
C. M. Perrins
(eds).
1993. The Birds of the Western Palearctic. Vol. VIII. Oxford Univ. Press, Oxford. Google Scholar
A. Daraktchiev
,
A. Germanov
1975. [Über die Nahrung des Neuntöters in dem Rhodopi- Gebirge]. Natura (Plovdiv) 7: 107–110. Google Scholar
G. Favini
,
L. Fornasari
,
L. Bottoni
,
R. Massa
1998. A video-taping approach to study nestling diet and parental care of Red-backed Shrike (Lanius collurio). IBCE Techn. Publ. 7: 76–78. Google Scholar
E. Gwinner
1961. Über die Entstachelungshandlung des Neuntöters. Vogelwarte 21: 36–17. Google Scholar
A. Hernandez
1993. [Nestling diet of three sympatric shrike species (Lanius spp.) : age-related, seasonal, and interspecific variations]. Dońana 20: 145–163. Google Scholar
A. Hernandez
1995. Temporal-spatial patterns of food caching in two sympatric shrike species. Condor 97: 1002–1010. Google Scholar
A. Hernandez
,
F. J. Purroy
,
J. M. Salgado
1993. [Seasonal variation, interspecific overlap, and diet selection in three sympatric shrike species (Lanius spp.)]. Ardeola 40: 143–154. Google Scholar
M. Hornman
,
M. Nijssen
,
M. Geertsma
,
J. Kuper
,
H. Esselink
1998. Temporal effects on diet composition in nestling Redbacked Shrike (Lanius collurio) in Bargerveen, the Netherlands. IBCE Techn. Publ. 7: 83–87. Google Scholar
M. K. Karg
2001. [Diet composition of the Red-backed Shrike (Lanius collurio L., 1758) near Turew (SE Wielkopolska)]. M.Sc. thesis, Adam Mickiewicz Univ. Poznań. Google Scholar
I. Korodi Gai
1969. Beiträge zur Kenntis der Brutbiologie und Brutnahrung der Neuntöter (Lanius collurio L.). Zool. Abh. Mus. Tier. Dresden 30: 57–82. Google Scholar
K. Kujawa
2002. Population density and species composition changes for breeding bird species in farmland woodlots in western Poland between 1964 and 1994. Agric. Ecosyst. Environ. 91: 261–271. Google Scholar
J. Kuper
,
Duinen G.-J. van
,
M. Nijssen
,
M. Geertsma
,
H. Esselink
2000. Is the decline of the Red-backed Shrike (Lanius collurio) in the Dutch coastal dune area caused by a decrease in insect diversity? Ring 22: 11–25. Google Scholar
S. Kuźniak
,
P. Tryjanowski
2000. Distribution and breeding habitat of the Red-backed Shrike (Lanius collurio) in an intensively used farmland. Ring 22: 89–93. Google Scholar
N. Lefranc
1979. Contribution a l'ecologie de la Pie-grieche ecorcheur Lanius collurio L. dans les Vosges Moyennes. L'oiseau et R.F.O. 49: 245–298. Google Scholar
N. Lefranc
1997. Shrikes and the farmed landscape in France. In:
D. J. Pain
,
M. W. Pienkowski
(eds).
Farming and birds in Europe. Academic Press, London, pp. 236–268. Google Scholar
N. Lefranc
,
T. Worfolk
1997. Shrikes. A Guide to the Shrikes of the World. Pica Press, Sussex. Google Scholar
U. Leugger-Eggimann
1997. Parental expenditure of Redbacked Shrikes, Lanius collurio, in habitats of varying farming intensity. Univ. Basel & Swiss Ornithological Institute, Sempach. Google Scholar
W. Mann
1983. Zur Ernährung des Neuntüters Lanius collurio L. in Abhängigkeit vom Insektenangebot auf verschiedenen Dauergrünlandtypen. Vogelkdl. Heft Edertal 9: 5–41. Google Scholar
W. Mann
1987. Ernährungsbiologie des Neuntöters Lanius collurio. Charadrius 23: 28–38. Google Scholar
K. Mansfeld
1958. Zur Ernährung des Rotrückenwürgers (Lanius collurio collurio L.), besonders hinsichtlich der Nestlingsnahrung, der Vertilgung von Nutz- und Schadinsekten und seines Einflusses auf den Singvogelbestand. Beitr. Vogelk. 6: 271–292. Google Scholar
S. Mielewczyk
1967. [On the food of the Red-backed Shrike, Lanius collurio L., near Gniezno (prov. of Poznań)]. Acta Ornithol. 10: 157–175. Google Scholar
V. Olsson
1995. The Red-backed Shrike Lanius collurio in southeastern Sweden: habitat and territory. Ornis Svec. 5: 31–41. Google Scholar
J. J. Purger
1998. Diet of Red-footed Falcon Falco vespertinus nestlings from hatching to fledgling. Ornis Fenn. 75: 185–191. Google Scholar
A. Randik
1970. [Red-backed Shrike (Lanius collurio) in natural conditions of Slovakia]. Prace a studie SOP pri SUPSOP Bratislava 3: 1–132. Google Scholar
S. M. Redpath
,
R. Clarke
,
M. Madders
,
S. J. Thirgood
2001. Assessing raptor diet: comparing pellets, prey remains, and observational data at Hen Harrier nests. Condor 103: 184–188. Google Scholar
K. V. Rosenberg
,
R. J. Cooper
1990. Approaches to avian diet analysis. Stud. Avian Biol. 13: 80–90. Google Scholar
R. E. Simmons
,
D. M. Avery
,
G. Avery
1991. Biases in diets determined from pellets and remains: correction factors for a mammal and bird-eating raptor. J. Raptor Res. 25: 63–67. Google Scholar
Z. Skarzyńska
1956. [Study of the nestlings food in the Redbacked Shrike (Lanius collurio L.)]. M.Sc. thesis, Adam Mickiewicz Univ., Poznań. Google Scholar
L. Szlivka
1977. [Some recent data on the biology of feeding of the Red-backed Shrike (Lanius collurio L.)]. Larus 29–30: 233–252. Google Scholar
P. Tryjanowski
,
S. Kuźniak
1999. Effect of research activity on the success of Red-backed Shrike Lanius collurio nests. Ornis Fenn. 76: 41–43. Google Scholar
P. Tryjanowski
,
S. Kuźniak
,
B. Diehl
2000. Breeding success of the Red-backed Shrike (Lanius collurio) in relation to nest site. Ornis Fenn. 77: 137–141. Google Scholar
D. Van Nieuwenhuyse
,
F. Nollet
,
A. Evans
1999. The ecology and conservation of the Red-backed Shrike Lanius collurio breeding in Europe. Aves 36: 179–192. Google Scholar
T. Wagner
1993. Saisonale Veränderungen in der Zusammensetzung der Nahrung beim Neuntöter Lanius collurio. J. Ornithol. 134: 1–11. Google Scholar
