How many?

In the April issue (Wild month), Ben Hoare tells us that up to 1,000 million willow warblers head to Europe each spring. This number astonished me. A few pages later Mark Carwardine warns us about exaggerated wildlife statistics, so I checked the BTO’s figure for the British population, which shows 2.3 million territories in recent years – say 5 million individuals to keep it simple. Are we really to believe that up to 995 million willow warblers are occupying the rest of Europe each summer?

Gerry Cotter, Lancaster