A comparative study of the food of some British Corvidae

Food of the Rook in Britain

“…Rderig 1900, Collinge 1910, 1924, Thring 1909, Madon 1928) and subsequently (e.g. Lockie 1956, 1959, Holyoak 1968, Pivar 1966, Folk and Touskova 1966, Hell and Sovig 1958.…”

Factors influencing the distribution of MagpiesPica picain an urban environment

“…It seems likely that the Magpie's unspecialised diet throughout its life cycle (Owen 1956;Holyoak 1968;Tatner, in press) may have been an important pre-adaptation for successful colonisation of urban areas. The present work has demonstrated that much of the Manchester urban environment provides an abundance of trees suitable for nesting, many of which are species preferred by the Magpie.…”

Rooks (Corvus frugilegus) dine on snails in Poland

“…Some authors claim that gastropods are only supplementary food, and that their frequency in the food does not exceed 5% (Gromadzka, 1980;Roosimaa, 1961;Holyoak, 1972). Only in a few papers related to research done in Great Britain (Holyoak, 1968;Holyoak, 1972) do the authors indicate molluscs as a complementary food. Based on the literature survey (Lockie, 1956;Holyoak, 1968Holyoak, , 1972Gromadzka, 1980), the percentage of molluscs in stomach contents is below 5% in Poland during the spring period from April to June, but as much as 10% in Great Britain from March to October.…”

“…Only in a few papers related to research done in Great Britain (Holyoak, 1968;Holyoak, 1972) do the authors indicate molluscs as a complementary food. Based on the literature survey (Lockie, 1956;Holyoak, 1968Holyoak, , 1972Gromadzka, 1980), the percentage of molluscs in stomach contents is below 5% in Poland during the spring period from April to June, but as much as 10% in Great Britain from March to October. Research on food consumption and digestion by the rooks, which also included food preferences (Luniak, 1977), showed that both terrestrial and freshwater molluscs were not attractive foodstuffs.…”

“…The collected snails were mainly 2 species: Roman snail, Helix pomatia, and grove snail, Cepaea nemoralis. Rook diets have been studied before (Roosimaa, 1961;Holyoak, 1968Holyoak, , 1972Jabłoński, 1979;Gromadzka, 1980), but rooks carrying intact shelled snails to the nest site had never been observed. Birds of prey detect their prey by sight (Allen, 1988).…”