Winter body mass of Pacific dunlins, by month. Summary by month of Pacific dunlin mean mass (g) measured on the Fraser River estuary during the winters of 1977/78, 1978/79 and 1979/80, for females (above) and males (below). Overall, the seasonal pattern of weights in the three years is similar. Samples contain only gender-assigned individuals, and thus exclude about 30% of individuals. Exact dates of capture vary somewhat between months and years. Samples sizes for individual entries range from 14 - 130; total sample size = 1883. Error bars are 95% confidence intervals.
Ydenberg et al. BMC Ecology 2010 10:1 doi:10.1186/1472-6785-10-1