Extended Data Fig. 1: Relationships between a hypothetical decrease in migration duration (days) and the required hypothetical decrease in total fuelling time (%).
From: Scope for waterfowl to speed up migration to a warming Arctic
a, ignoring pre-departure fuelling; b, including pre-departure fuelling. Panel b is identical to Fig. 3a. Each thin line represents one tracked spring migration and its slope is derived from that spring migration and indicates how much that migration would have been shortened (in days) by a certain percentage decrease in fuelling time. Thick dashed lines indicate the median slope per population. When pre-departure fuelling was ignored, birds appear more limited in their scope to speed up spring migration, particularly barnacle and brent geese.
