Response of rare and endangered species Picea omorika to climate change: The need for speed

Abstract

Serbian spruce (Picea omorika (Pančić) Purk.) is a rare and endangered tertiary relict and endemic species, with restricted and fragmented natural range in Serbia and Bosnia and Herzegovina, mainly around the mid-course of the Drina river. Since the middle of the 19th century, its natural range declines constantly, followed by a decline in the number of mature individuals. The decline of this forest species is slow and mainly attributed to poor regeneration and low competing ability. Given the foreseen worsening of the climate in forthcoming decades, this decline can only accelerate. In recent years, dieback related to drought has been observed as response to extreme weather events suggesting that Serbian spruce will face difficulties in adapting to climate change within its natural range. However, successful use of Serbian spruce in Central and Northern Europe indicates potentially large adaptive potential of this species which, along with the high genetic variability, outweigh the limited morphological variation, self-fertilization, and limitations related to the restricted natural range in the first place, and, indicates possible directions of migration in the second place. In this paper, current conservation actions are discussed, and strategies for the species survival in a changing environment are suggested. Since migration and adaptation are the least likely responses of this species to climate change, measures such as assisted migration may be the only strategy which will enable persistence of Serbian spruce. Current conservation programs, limited to in-situ actions, need to be supplemented with ex-situ actions and strategies. In the worst case scenario, i.e. for species such as Serbian spruce which are unable to migrate and/or adapt to changing climate, the most suitable sites should be identified and colonized in order to prevent extinction in the near future.