Plants are moving northward to find cooler habitats, so it would seem that the blog I wrote earlier on human assisted migration might be moot – they’re doing it for themselves.
Using DNA fingerprinting techniques, a study by Inger Greve Alsos and her colleagues has found that ‘long-distance colonization of a remote arctic archipelago, Svalbard, has occurred repeatedly and from several source regions.’ In order to reach their destination, most plants have travelled more than 620 miles, probably arriving on drifting sea ice and the wind. However, species’ temperature requirements will restrict colonisation so, even if dispersal is unlimited, plants favouring cold conditions will have nowhere to go.
And this may all come sooner than expected. The retreat of Arctic sea ice is predicted to accelerate rapidly, and the University Corporation for Atmospheric Research in the US has predicted that ‘the Arctic Ocean could become nearly devoid of ice during summertime as early as 2040.’
It now also appears that seasons in the arctic are arriving much earlier than they once were, with spring an average of six to eight days earlier than 30 years ago, and the local organisms are acting accordingly, with earlier flowering and emergence. Research by Toke Hoye from the University of Aarhus, Denmark has been published this week and finds that over time the ecosystem stability may be affected. Species from southern latitudes will ‘establish themselves (in the region) and increase competition for food.’ So while more species are finding this region accessible, those already there may suffer and long term survival may be affected, and this could as well as disruption of the food chain. See the BBC story.
So, it’s good news for the plants looking for new homes, not so good for the species already there, and hopeless for at least one of those, the Polar Bear, unless they too can adapt …