AVIS-IBIS

Birds of Indian Subcontinent

Population trends of Jays, Magpies, Jackdaws and Carrion Crows in the United Kingdom

Publication Type:Journal Article
Year of Publication:1996
Authors:Gregory, RD, Marchant, JH
Journal:Bird Study
Volume:43
Issue:1
Date Published:1996
ISBN Number:0006-3657
Keywords:Coloeus, Coloeus monedula, Corone, Corone corone, Corvidae, Corvus, Corvus cornix, Corvus corone, Corvus corone corone, Corvus monedula, Garrulus, Garrulus glandarius, Pica, Pica hudsonia, Pica pica, United Kingdom
Abstract:Population trends of Jay Garrulus glandarius, Magpie Pica pica, Jackdaw Corvus monedula and Carrion Crow Corvus corone were examined over the period 1964?93 using data from the Common Birds Census. Population growth has been highest in the Magpie and Carrion Crow, although both these have shown a reduction in the rate of growth from the late 1970s. Densities of all 4 corvids have increased on farmland, whereas only Magpie and Carrion Crow have increased in woodland. Population trends were associated with farmland type in all the corvids; the strongest increases were on mixed and grazing farms and the smallest on arable farms. There were strong regional differences in trends within woodland and farmland. Our results are discussed in the context of the long%term changes in corvid populations that have been reported since the start of this century.Population trends of Jay Garrulus glandarius, Magpie Pica pica, Jackdaw Corvus monedula and Carrion Crow Corvus corone were examined over the period 1964?93 using data from the Common Birds Census. Population growth has been highest in the Magpie and Carrion Crow, although both these have shown a reduction in the rate of growth from the late 1970s. Densities of all 4 corvids have increased on farmland, whereas only Magpie and Carrion Crow have increased in woodland. Population trends were associated with farmland type in all the corvids; the strongest increases were on mixed and grazing farms and the smallest on arable farms. There were strong regional differences in trends within woodland and farmland. Our results are discussed in the context of the long%term changes in corvid populations that have been reported since the start of this century.
URL:http://www.tandfonline.com/doi/abs/10.1080/00063659609460993
Short Title:Bird Study
Taxonomic name: 
Coloeus (Birds), Coloeus monedula (Birds), Corvidae (Birds), Corvus (Birds), Corvus cornix (Birds), Corvus Cornix (Birds), Corvus corone (Birds), Corvus Corone (Birds), Corvus Monedula (Birds), Garrulus (Birds), Garrulus glandarius (Birds), Pica (Birds), Pica pica (Birds)
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith