Study concludes that migratory birds have limited potential to help plants cope with climate change
The results of this research are crucial to understanding, halting and mitigating the effects of climate change on biodiversity.
A Blackcap Warbler (Sylvia atricapilla) feeding on the fruit of a Dogwood (Cornus sanguinea). This plant has a short fruiting period in autumn, when Blackcap Warblers are migrating south. Therefore, the warblers that eat its fruits are likely to carry these seeds south where they will be exposed to warmer temperatures in the future.
© Luis Ojembarrena
Abridged version in English by Diana Taborda
A study published today in the journal Nature, involving researchers from 13 European institutions, including the University of Coimbra (Centre for Functional Ecology | UC) and the University of Porto (UP), concludes that migratory birds mainly disperse seeds in the opposite direction to that needed to help plants cope with climate change.
Migratory birds can help plants adapt to climate change by eating their fruits and dispersing their seeds to more favourable locations. However, this new study shows that the vast majority of seed species from European forests are dispersed by birds during their migration towards warmer, southern latitudes, and only a minority to cooler, northern latitudes - contrary to what plants would need to adapt to global warming.
The results of this research are crucial to understanding, halting and mitigating the effects of climate change on biodiversity.
As a result of global warming, the ideal climatic conditions for species are shifting towards cooler latitudes, leading to a redistribution of biodiversity on a planetary scale. In Europe, this movement is from south to north. But while animals can move independently, plants are largely dependent on fruit-eating animals, and in particular migratory birds, to spread their seeds to places with more favourable conditions.
The study shows that only 35% of plant species are dispersed by birds as they migrate north, while 86%, the vast majority of species, are dispersed as the birds that consume their fruit fly to warmer southern latitudes.
The authors of the study suggest that this difficulty in finding suitable dispersers may determine the specific composition of European forests in the future, as many plants may be left behind. Plant species that cannot keep up with the shift in their preferred survival conditions will have to cope with drier, warmer and drier climates in the south.
Full scientific article available here.