Body mass (mean ± SD) of red knots (<i>Calidris canutus piersmai</i>) captured on different dates.

Abstract

<p>A total of 486 birds were sampled in 2008–2012 on the coast of the north Yellow Sea during northward migration. The solid line indicates least-square linear regression of total birds and the dashed lines indicate the linear regression of the females (red) and the males (blue).</p