Deforestation is part of it. With continued climate change, such drought or flood events will only get more and more frequent outside of the equatorial region, with the most severe adverse weather events expected between 30°N and 60°N. The ocean will buffer the UK a bit from temperature extremes, but the inherent seasonality of the climate will still result in large variations in both temperature and precipitation. The temperature of the Atlantic Ocean is a major influence as well.

Convert the pasture lands to syntropic food forests and native forests, and then the birds and other native animals will have a place to live again.