The Dartford Warbler is found in a few localised places in the UK. Back in early1960’s following servere winters Dartford warblers numbers crashed and only10 pairs remained (They only eat insects and do not migrate for the winter, which means it is vulnerable to cold weather and prolonged snow cover ). On a positive note today, there are about 3,200 pairs nesting.
They are dependent on dry heath habitats, particularly on gorse in good condition. It is a ground-nesting bird, preferring to breed under the protective cover of dense heather or compact gorse. It makes a grassy, cup-shaped nest, in which it lays three to five eggs. It can have up to three broods from April to July.
A bird I only saw once in my childhood today I know of 4 places where they are doing well close to my home.