This paper reports on the 16th year of the Common Birds Census, and details index changes between the years 1976–1977. The largest increase noted this year was 54% for Chifichaffs on farmland (39% in woodland), while the biggest decline was one of 33% for Little Owls.
No takes yet. Share an insight, caveat, or question.
J. H. Marchant (1978) studied this question.
Synapse has enriched 5 related papers. Consider them for comparative context: