Number of tubers for each tuber length (mm) in a representative swan esophagus (a) and collected from sediment cores of the four studied wetlands in September (a) and March (b). Note that absolute number of tubers is presented to show differences in tuber density among wetlands and seasons. Mean ± 1SE of tuber length for swans: mm, Unit 1: mm, Unit 2: mm, Unit 4: mm, BRC: mm.
