Britain has a new snake species – should climate change mean it is allowed to stay?

The introduction and survival of Aesculapian snakes in north Wales should mark a rethink on conservation attitudes, write Tom Major and Wolfgang Wüster

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ALL ANIMALS live in or seek a set of climate conditions they find tolerable. This “climate envelope” partially determines where animals are found, but the continued existence of many species now rests on the outcome of human-driven climate change.

Rising temperatures are moving the available climate niches of many species into areas which were previously too cool. While their ranges shift poleward or to higher elevations, their habitat downslope or closer to the equator shrinks, as it becomes too hot to live in.

Flying and marine animals are relatively free to follow these shifting niches. Birds and butterflies are two examples. New species arrive regularly in the UK with the warming climate and are generally met with excitement by enthusiasts and scientists alike, given that they are a natural effort by a species to make the best of a difficult situation.

However, many grounded species, including reptiles and mammals, cannot disperse through habitats split apart by roads and other human-made obstacles, or cross natural barriers like the Channel. This limits their ability to find suitable conditions and makes them vulnerable to extinction.

Nowhere to go?

Here is the dilemma for conservationists like us.

We normally focus on preserving species within their modern ranges, and have traditionally viewed species that end up outside theirs as a problem. But retaining the status quo is increasingly untenable in the face of unchecked climate change.