Data from: Body shrinkage due to Arctic warming reduces red knot fitness in tropical wintering range

Reductions in body size are increasingly being identified as a response to
climate warming. Here we present evidence for a case of such body
shrinkage, potentially due to malnutrition in early life. We show that an
avian long-distance migrant (red knot, Calidris canutus canutus), which is
experiencing globally unrivaled warming rates at its high-Arctic breeding
grounds, produces smaller offspring with shorter bills during summers with
early snowmelt. This has consequences half a world away at their tropical
wintering grounds, where shorter-billed individuals have reduced survival
rates. This is associated with these molluscivores eating fewer deeply
buried bivalve prey and more shallowly buried seagrass rhizomes. We
suggest that seasonal migrants can experience reduced fitness at one end
of their range as a result of a changing climate at the other end.