云雀
In the UK, Eurasian skylark numbers have declined over the last 30 years, as determined by the Common Bird Census started in the early 1960s by the British Trust for Ornithology. There are now only 10% of the numbers that were present 30 years ago. The RSPB have shown that this large decline is mainly due to changes in farming practices and only partly due to pesticides. In the past cereals were planted in the spring, grown through the summer and harvested in the early autumn. Cereals are now planted in the autumn, grown through the winter and are harvested in the early summer. The winter grown fields are much too dense in summer for the Eurasian skylark to be able to walk and run between the wheat stems to find its food.