Intervention offers 'best chance' to save species endangered by climate change, expert argues

Chris Thomas, Professor of Conservation Biology, says the strategy is applicable across the world, and he suggests Britain as a potential haven for species such as the Iberian lynx, the Spanish Imperial Eagle, the Pyrenean Desman and the Provence Chalkhill Blue butterfly.

In an opinion paper in Trends in Ecology and Evolution, Professor Thomas, of the University's Department of Biology, says that moving endangered species is the only viable option to maintain some climate-endangered species in the wild.

He says: "Expanding the dispersal of endangered species may represent the most effective climate change adaptation strategy available to conservationists to reduce extinction rates across the globe."

Guidelines on releases into the wild for the conservation purposes condone only the release of a species into an area where it used to occur -- re-introduction rather than introduction -- with aim of the recovery of a species in its native range and/or restoring the ecological community.

But Professor Thomas says a more radical policy is now required if humanity wishes to minimise the number of species that become extinct from all causes, including from climate change and species invasions. He says increased local and regional species richness that would result is positive, provided that this does not result in higher global extinction rates.

"Translocation represents one of the principal means of saving species from extinction from climate change; in conjunction with maintaining large areas of high quality (low human impact) habitats," he says.

"We need to develop a long 'shopping list' of potential translocations and, where possible, put in place monitoring of extant populations to help identify when action is needed. The later we leave it, the harder and more expensive translocations will become."

"Each species should be considered carefully to judge the balance between the potential benefits of helping to save a species from extinction and any changes to existing species within the UK."

Professor Thomas says Britain is an ideal recipient location for translocated species. Earlier research found that around 2,000 introduced species have become established in Britain without indigenous species being destroyed as a consequence.

"A British Assisted Regional Colonisation area would contribute to the conservation of globally threatened species," he adds.

He says that the risks to Britain's indigenous species would be small because the translocations would take place within the same broad geographic region. Professor Thomas argues that the largest declines of indigenous species, such as the red squirrel, in Britain stem from long-distance translocation such as introductions from North America which would not normally be sanctioned under a deliberate assisted colonisation policy.

Species that could be considered for translocation to the UK. In each case, natural colonisation is highly improbable.

• Pyrenean desman Galemys pyrenaicus. A distinct (monotypic genus) semi-aquatic insectivorous mammal, restricted to streams in the Pyrenees/NW Iberia.Threatened by climate change; establishment in streams in western Britain may be feasible.
• Iberian lynx Lynx pardinus. The world's most endangered cat, restricted to the Iberian Peninsula. L.pardinus is descended from lynx that lived more widely in Europe before the late Pleistocene (around 100-200 thousand years ago) arrival of the now-widespread Eurasian lynx, Lynx lynx. Establishment of L.pardinus in Britain would represent a greater contribution to world conservation than re-introducing L.lynx. Rabbits, the main prey of L.pardinus, are abundant in southern Britain.
• Spanish Imperial eagle Aquila heliacea adalberti. An extremely rare eagle endemic to Spain and Portugal. Potentially threatened by climate change; its main prey is also the rabbit.
• Provence Chalkhill Blue Polyommatus hispanus. A butterfly restricted to northern Spain, southern France and northern Italy. At serious risk of extinction from climate change; southern England is predicted to become climatically suitable. The butterfly's host plant grows on calcareous grasslands in southern England.
• de Prunner's Ringlet Erebia triaria. Endemic to southern European Mountains and threatened by climate change; projections suggest that England may represent a considerable portion of the potential new range. The butterfly's larvae feed on grass species already common in Britain.
• Iberian water beetles. Many of the 120 water beetle species endemic to the Iberian Peninsula are narrow endemics that occupy head water streams in one or a few mountain ranges. Increased droughts threaten them.
• Caucasian endemics. Many species are endemic to the Caucasus Mountains and to disjunct humid forests of the eastern Black Sea coast and southern Caspian. Major reductions in summer precipitation are projected for that region, threatening moisture-dependent species. For example, Caucasian Wingnut Tree Pterocarya fraxinifolia is restricted to moist habitats in the Caucasus, Turkey and Iran. It grew wild in the British Isles in previous warm periods, hundreds of thousands of years ago, and establishes in gardens today.