A Curious eastern grey squirrel (Sciurus carolinensis).
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New research suggests the gut bacteria of red and grey squirrels differ significantly, potentially explaining the decline of the native red and the success of its grey counterpart.
A hippo swims in the Magdalena river, Colombia.
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Pablo Escobar’s hippos escaped in the 1990s – since then, they have become a problem.
Red squirrels have little immunity to squirrelpox virus spread by grey squirrels.
Hugh Rowlands
There is no single, straightforward way to safeguard the future of this native mammal at the moment – but here are some options
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Squirrel feeders laced with contraceptives could be used to suppress grey squirrels in the UK.
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Scientists hope to learn what makes certain red squirrels able to survive squirrelpox.
A European pine marten climbing a tree in the Levoča Mountains, Slovakia.
František Koneval
Where pine martens have recovered, red squirrels have tended to benefit while grey squirrels have declined. Scientists weren’t sure why – until now.
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If harm to native wildlife is the main concern then there are much bigger targets for control than grey squirrels.
The pine marten – cute but cunning.
Karen Bullock/Flickr
We should welcome a native predators’ return across the British Isles, while at the same time being honest about the implications.
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Formby is one of the only remaining urban areas in England where red squirrels can be found at all.
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Grey squirrels are wreaking havoc on UK woodlands.
Jason Gilchrist / jasongilchrist.co.uk
Grey squirrels have lots of attractive characteristics, yet they are actively persecuted by humankind.
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Grey squirrels hate these reclusive, cat-sized predators.