Wind effects Godwit migrations from Alaska to Australasia differently

In the role of wind in Bar-tailed Godwit migrations, this graphic shows each line as one godwit as it flew from Alaska to Australasia in 6 hour increments. The plotted values (y-axis) are ratios derived by dividing the distance the godwit flew through the air (air distance) by the distance the godwit traveled over the earth (ground distance). Strategically, almost all godwits chose a time to depart Alaska that capitalized on markedly favorable tailwinds. Thereafter, most godwits experienced favorable or near-neutral wind conditions throughout their flight south (i.e., most lines are near or below 1.0). However, three satellite-tracked godwits encountered challenging headwinds as they crossed the North Pacific. Source of this figure is: Gill, R. E., Jr., D. C. Douglas, C. M. Handel, T. L. Tibbitts, G. Hufford, and T. Piersma. 2014. Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific. Animal Behaviour 90:117-130. doi:10.1016/j.anbehav.2014.01.020