Size classes of fields (ha) | |||||
Year | <4 | 4-16 | 8-16 | 16-32 | >32b |
Mayfield nest successa | |||||
1966b | 4.7 (37) | --c (0) | -- (0) | -- (0) | -- (0) |
1967 | 4.7 (15) | 3.8 (15) | 4.6 (31) | 4.3 (57) | -- (0) |
1968 | 2.4 (14) | 13.5 (15) | 7.0 (61) | 10.5 (34) | 2.1 (13) |
1969 | 25.5 (13) | 26.7 (25) | 37.1 (67) | 17.8 (41) | -- (0) |
1970 | 6.9 (30) | 12.1 (42) | 13.4 (63) | 17.1 (56) | 8.1 (90) |
1971 | 34.9 (28) | 16.4 (20) | 32.9 (59) | 39.9 (30) | 24.2 (87) |
1972 | 8.2 (27) | 9.1 (44) | 9.0 (77) | 9.7 (65) | 14.0 (136) |
1973 | 4.2 (13) | 14.3 (27) | 7.3 (55) | 5.4 (17) | 11.7 (71) |
1974 | 19.5 (25) | 30.8 (50) | 14.3 (61) | 17.9 (40) | 18.3 (136) |
1975 | 15.6 (26) | 16.4 (72) | 23.2 (83) | 18.7 (48) | 12.7 (201) |
1976 | 16.9 (22) | 5.8 (64) | 10.6 (83) | 9.0 (55) | 17.5 (129) |
1977 | 18.0 (10) | 10.8 (24) | 34.8 (49) | 10.7 (26) | 30.0 (40) |
1978 | 28.8 (29) | 29.1 (65) | 33.0 (143) | 13.2 (53) | 37.6 (128) |
1979 | 43.2 (4) | 9.2 (18) | 28.8 (81) | 16.9 (34) | -- (0) |
1980 | 14.7 (8) | 9.7 (17) | 15.3 (48) | 6.0 (16) | -- (0) |
1981 | 31.6 (6) | 6.4 (14) | 16.0 (25) | 32.8 (18) | 24.7 (78) |
Total | 13.4 (307) | 14.7 (512) | 18.7 (986) | 13.3 (590) | 17.8 (11,109) |
Mayfield nest densities | |||||
1966 | -- | -- | -- | -- | -- |
1967 | 150 | 38.8 | 39.8 | 45.2 | -- |
1968 | 929 | 32.1 | 62.0 | 27.3 | 53.1 |
1969 | 235 | 37.4 | 49.1 | 20.8 | -- |
1970 | 178 | 69.5 | 46.2 | 26.9 | 34.2 |
1971 | 88.8 | 40.4 | 27.4 | 11.3 | 22.3 |
1972 | 70.4 | 64.1 | 50.3 | 35.5 | 36.1 |
1973 | 102 | 30.8 | 39.6 | 8.7 | 20.7 |
1974 | 77.6 | 27.8 | 36.7 | 22.2 | 33.2 |
1975 | 59.0 | 76.0 | 37.8 | 27.6 | 49.8 |
1976 | 91.1 | 77.4 | 37.5 | 43.4 | 28.9 |
1977 | 60.1 | 30.9 | 18.1 | 24.3 | 9.9 |
1978 | 77.8 | 57.8 | 51.5 | 32.7 | 26.2 |
1979 | 57.9 | 85.7 | 113 | 152 | -- |
1980 | 85.2 | 109 | 101 | 16 | -- |
1981 | 73.1 | 43.6 | 27.5 | 15.8 | 17.1 |
Total | 114 | 50.8 | 43.3 | 28.5 | 27.8 |