Refining predictions of population decline at species’ rear edges

VILÀ-CABRERA, ALBERT; PREMOLI, ANDREA C.; JUMP, ALISTAIR S.

GLOBAL CHANGE BIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2019 p. 1549 - 1560

1354-1013

According to broad-scale application of biogeographical theory, widespread retractions ofspecies? rear edges should be seen in response to ongoing climate change. This predictionrests on the assumption that rear edge populations are ?marginal? since they occur at the limitof the species? ecological tolerance and are expected to decline in performance as climatewarming pushes them to extirpation. However, conflicts between observations andpredictions are increasingly accumulating and little progress has been made in explaining thisdisparity. We argue that a revision of the concept of marginality is necessary, together withexplicit testing of population decline, which is increasingly possible as data availabilityimproves. Such action should be based on taking the population perspective across a species?rear edge, encompassing the ecological, geographical and genetic dimensions of marginality.Refining our understanding of rear edge populations is essential to advance our ability tomonitor, predict and plan for the impacts of environmental change on species rangedynamics.