Acid deposition :: Thrushes

Latin name: 
Turdus spp.

Impact Type: Deposition of pollutant

Key Concerns:

This genus includes song thrush, mistle thrush, blackbird, fieldfare and redwing. Green (1998) has suggested that acid deposition can affect eggshell thickness in thrushes (Turdus spp.). Anthropogenic acid deposition can significantly reduce levels of available calcium in soil and the abundance of calcareous items such as snail shells. Recent research in areas adversely affected by acid deposition in continental Europe has suggested that reduced calcium availability has resulted in an increased incidence of eggshell defects in small birds (Pyatt et al. 1998).

Additional Comments:

Numbers of thrushes especially the song thrush, our resident thrush which is less dependent on berries, are declining, although the blackbird, a more dominant feeder, is on the increase. Human impact via change in land use (garden) management probably presents the greatest threat. 

Critical Load/level: 
Critical Load/ Level

No estimate available

References: 
Green, R.E. 1998 Long-term decline in the thickness of eggshells of thrushes, Turdus spp., in Britain Proceedings of the Royal Society 265 679-684
Pyatt, F.B.; Lacy, D.; Pyatt, A.J. 1998 Some effects of acid rain on the mobilisation of elements from bird eggs. Fresenius Environmental Bulletin 7 334-337
Species group: 
Pollutant: