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BTO Blueline
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BTO Blueline
Corvus monedula
Jackday © Tommy Holden

• Population

• Productivity

• Additional

Conservation listings
Europe: no SPEC category (concentrated in Europe, conservation status favourable)
UK: green
Long-term trend
UK, England: moderate increase
UK population size
555,000 territories in 2000 (1988–91 Atlas estimate updated using CBC/BBS trend: BiE04, APEP06)
Status summary
Jackdaws have increased in abundance since the 1960s (Gregory & Marchant 1996), and more recent BBS data suggest that the increase is continuing in all UK countries. As with Magpie, Rook and Carrion Crow, the increase has been associated with improvements in breeding performance and probably reflects the species' generalist feeding habits, which allow it to exploit diverse and ephemeral food resources. A minor decrease in average brood size has been countered by substantial declines in nest failure rates during the egg and chick stages. Overall, from egg-laying to fledging, the proportion of nests that fail has fallen by about two-thirds. Typically in this species, the younger chicks of a brood perish quickly if food becomes limited. Increases in fledging success are therefore likely to be due to improved parental provisioning success (Henderson & Hart 1993).

Population changes

CBC/BBS UK graph
BBS acknowledgement
CBC/BBS England graph
BBS UK graph
BBS England graph
BBS Scotland graph
BBS Wales graph
BBS N Ireland graph

Productivity trends

Clutch size graph
Brood size graph
Egg nest failure graph
Chick nest failure graph
Laying date graph



Insufficient data for CES
available for this species


Additional information

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This report should be cited as:
Baillie, S.R., Marchant, J.H., Leech, D.I., Joys, A.C., Noble, D.G.,
Barimore, C., Grantham, M.J., Risely, K. & Robinson, R.A. (2009).
Breeding Birds in the Wider Countryside: their conservation status 2008.
BTO Research Report No. 516. BTO, Thetford. (http://www.bto.org/birdtrends)

Pages maintained by Iain Downie, Mandy T Andrews and Laura Smith: Last updated 18.02.2009