Patrick Barkham is rightly worried about the impacts of urbanisation on our wildlife (Notebook, 13 December). London is home to more than 13,000 species of fauna, flora and fungi, but we are expected to accommodate a population increase equivalent to the size of Leeds by 2050, and building density can only go so far before our needs override those of others we share our city with. While flowering buddleia, dashing parakeets and curious foxes demonstrate adaptability to this brave new world, there are many more species that simply can’t cope – with higher density we’ll lose precious diversity. The London assembly is currently looking at how new housing can do more to conserve wildlife, and we’re encouraged by Mayor Khan’s talk of “good growth” as he sets out his early plans for the capital. We need real commitment to making room for nature and, importantly, room for London to breathe.

Mathew Frith

Director of conservation, London Wildlife Trust

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