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YELLOWHAMMER Emberiza citrinella
 
Conservation Listings Long term trend

Unlisted/Green
Biodiversity Steering Group
Conservation Concern List

UK: Rapid decline
Farmland: Moderate decline
Woodland: Rapid decline
Scrub (CES): Rapid decline
 
Status Summary
Yellowhammer abundance began to decline on farmland in the mid-1980s and the decline has continued ever since, the CBC trend being replicated in the CES and BBS results. The woodland CBC trend shows a longer term decline, perhaps showing problems for the species in this secondary (perhaps sink) habitat before they were apparent in the preferred farmland habitats. Yellowhammer breeding performance has tended to increase and there is some evidence that survival rates have been lower during the period of decline (Siriwardena et al. 1998b, 2000b). In addition to increases in clutch and brood size, nest failure rates have fallen: the proportion of nests failing at the egg stage (15 days, comprising 12 days incubation + 3 days laying) fell from 55% to 38%, and at the chick stage (12 days) from 45% to 38%. Overall the failure rates from egg laying to fledging fell from 75% to 62%; these values are relatively high, probably because later season nests, which tend to be more successful (Kyrkos 1997), are probably under-represented in the NRS dataset - such a factor is unlikely to affect overall trends. Reductions in winter seed food availability as a result of agricultural intensification (for example, the loss of winter stubbles and declining weed densities) are widely believed to have contributed to the decline.
 
 
Table of population changes for Yellowhammer
Source Period
(yrs)
Years Plots
(n)
Change
(%)
Lower
limit
Upper
limit
Alert Comment
CBC all habitats 30 1968-1998 133 -54 -63 -45 >50  
  25 1973-1998 134 -56 -63 -47 >50  
  10 1988-1998 111 -44 -51 -39 >25  
  5 1993-1998 105 -23 -30 -18    
CBC farmland 30 1968-1998 75 -42 -55 -29 >25  
  25 1973-1998 73 -45 -56 -36 >25  
  10 1988-1998 69 -40 -48 -32 >25  
  5 1993-1998 66 -23 -28 -16    
CBC woodland 30 1968-1998 34 -74 -85 -59 >50  
  25 1973-1998 35 -74 -84 -61 >50  
  10 1988-1998 28 -60 -76 -44 >50  
  5 1993-1998 25 -34 -56 -11 >25  
CES adults 14 1984-1998 23 -58 . . [>50*]  
  10 1988-1998 25 -35 . . [>25]  
  5 1993-1998 23 -15 . .    
CES juveniles 14 1984-1998 12 -73 . . [>50*] Small sample
  10 1988-1998 13 -69 . . [>50*] Small sample
  5 1993-1998 12 -35 . . [>25] Small sample
BBS UK 5 1994-1999 982 -16 -20 -11    
BBS England 5 1994-1999 853 -15 -20 -11    
BBS Scotland 5 1994-1999 86 -13 -28 6    
BBS Wales 5 1994-1999 35 -31 -52 -2 (>25) Small sample

The Breeding Bird Survey is jointly funded by BTO, JNCC and RSPB

 
 
Table of productivity information for Yellowhammer
Variable Period
(yrs)
Years Mean
annual
sample
Trend Predicted
in first year
Predicted
in last year
Change Comment
Clutch size 30 1968-1998 44 Linear increase 3.38 eggs 3.53 eggs 0.15 eggs  
Brood size 30 1968-1998 69 Curvilinear 2.96 chicks 3.19 chicks 0.23 chicks  
Daily failure rate (eggs) 30 1968-1998 66 Curvilinear 0.0517 nests/day 0.0317 nests/day -0.02 nests/day  
Daily failure rate (chicks) 30 1968-1998 51 Curvilinear 0.0479 nests/day 0.0385 nests/day -0.0094 nests/day  
Laying date 30 1968-1998 26 None       Small sample
Percentage juveniles (CES) 14 1984-1998 26 Smoothed trend 113 productivity index 100 productivity index -11%  
Percentage juveniles (CES) 10 1988-1998 28 Smoothed trend 194 productivity index 100 productivity index -49%[>25]  
Percentage juveniles (CES) 5 1993-1998 26 Smoothed trend 88 productivity index 100 productivity index 14%  
 
   



The report should be cited as: Baillie, S.R., Crick, H.Q.P., Balmer, D.E., Bashford, R.I., Beaven, L.P., Freeman, S.N., Marchant, J.H., Noble, D.G., Raven, M.J., Siriwardena, G.M., Thewlis, R. and Wernham, C.V. (2001) Breeding Birds in the Wider Countryside: their conservation status 2000. BTO Research Report No. 252. BTO, Thetford. (http://www.bto.org/birdtrends)

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