ECOLOGY. For the article “Avian migration phenology and global climate change,” by Peter A. Cotton, which appeared in issue 21, October 14, 2003, of Proc. Natl. Acad. Sci. USA (100, 12219–12222; first published September 30, 2003; 10.1073/pnas.1930548100), the author notes that the entries in the last two columns of Table 1 were printed out of order. The corrected table appears below.
Table 1. Slopes of linear regressions for 20 species of migrant bird in Oxfordshire (1971 to 2000).
| Species | Arrival date vs. year | Departure date vs. year | Duration vs. year | Arrival date vs. African winter temperature anomaly | Departure date vs. minimum Oxford temperature |
|---|---|---|---|---|---|
| Common Cuckoo, Cuculus canorus | -0.51 | -0.93 | -0.58 | 0.05 | -2.51 |
| Common Swift, Apus apus | -0.30 | -0.06 | 0.20 | -6.29 | -4.26 |
| European Turtle-Dove, Streptopelia turtur | -0.31 | -0.29 | -0.35 | -1.92 | -1.97 |
| Little Ringed Plover, Charadrius dubius | -0.76 | -0.81 | -0.15 | -10.52 | -5.88 |
| Eurasian Hobby, Falco subbuteo | -0.04 | 0.56 | 0.58 | 8.37 | 1.57 |
| Spotted Flycatcher, Muscicapa striata | -0.25 | -0.08 | 0.18 | 0.45 | -2.62 |
| Common Redstart, Phoenicurus phoenicurus | -0.09 | 0.12 | 0.07 | -0.48 | -1.07 |
| Whinchat, Saxicola rubetra | 0.07 | 0.53 | 0.39 | -4.98 | 4.65 |
| Northern Wheatear, Oenanthe oenanthe | -0.37 | 0.11 | 0.58 | 1.33 | 0.33 |
| Sand Martin, Riparia riparia | -0.58 | -0.38 | 0.18 | -1.47 | 0.02 |
| Barn Swallow, Hirundo rustica | -0.44 | -0.50 | 0.05 | -8.02 | -5.56 |
| Northern House-Martin, Delichon urbica | -0.67 | -0.65 | 0.02 | -7.10 | -4.76 |
| Common Grasshopper-Warbler, Locustella naevia | -0.27 | -0.75 | -0.58 | 1.53 | -0.06 |
| Sedge Warbler, Acrocephalus schoenobaenus | -0.23 | -0.39 | -0.27 | -6.26 | -4.23 |
| Eurasian Reed-Warbler, Acrocephalus scirpaceus | -0.31 | -0.46 | -0.19 | -3.14 | -5.27 |
| Willow Warbler, Phylloscopus trochilus | -0.07 | -0.34 | -0.29 | -0.26 | -9.55 |
| Garden Warbler, Sylvia borin | -0.03 | -0.39 | -0.18 | -3.24 | -0.40 |
| Common Whitethroat, Sylvia communis | -0.23 | 0.18 | 0.63 | -1.96 | -0.78 |
| Lesser Whitethroat, Sylvia curruca | 0.02 | -0.54 | -0.46 | 2.21 | -7.58 |
| Yellow Wagtail, Motacilla flava | 0.04 | -0.23 | -0.28 | -0.94 | -0.22 |
| Mean | -0.268 | -0.266 | -0.022 | -2.131 | -2.506 |
| SE | 0.053 | 0.092 | 0.084 | 0.958 | 0.758 |
| One-sample t test | -5.033 | -2.887 | -0.267 | -2.225 | -3.309 |
| Significance (2-tailed) | <0.001 | <0.009 | >0.05 | <0.05 | <0.004 |
Arrival date, departure date and duration of stay in Oxfordshire against year; arrival date in Oxfordshire against African winter temperature anomaly (°C); departure date from Oxfordshire against minimum and maximum Oxford temperature anomaly (°C). A one-sample t test was used to test each mean against the null hypothesis of no effect (a slope of zero).