Figure 5

Average bird group abundance ((a) shorebirds, (b) herons, (c) waterfowl, and (d) land birds) values between eco-friendly fields (EFF) and conventional fields (CF) according to main occurrence period (shorebirds: April–May, and August–September; herons: May–October; waterfowl: October–April; land birds: all seasons). The sample size was 36, which is the number of surveys (once per month for 3 years, from January 2014 to December 2016).