Jan Van Gils – Arctic warming felt by the Knot even in the Tropics

Jan van Gils is appointed as honorary professor of Global Change Ecology of Migrant Shorebirds at the University of Groningen. As an ecologist, Van Gils (NIOZ and UG) investigates shorebirds, with a particular focus on the red knot, which breeds in the Arctic and migrates through the Netherlands to its winter quarters in West Africa. 

The world is warming up rapidly, and especially the Arctic. This area has warmed up three times faster in recent years than the rest of the Earth. This is precisely the breeding ground of many of ‘our’ wading birds, which either winter with us or migrate to more southerly places. This applies, for example, to the Knot, for which we were able to demonstrate that negative climate effects, incurred during the chick phase in the far north of Siberia, have an effect on the adult phase in West Africa. It turns out that chicks grow less well in warm years, and are therefore relatively smaller as adults. Once in Africa, these small birds have less access to the buried shellfish as a result of their shorter beaks and are forced to eat seagrass, which significantly reduces their chances of survival.  The plummeting population size of this Afro-Siberian Knot therefore appears to be a direct consequence of the rapid warming of the Arctic.