Blackcaps typically visit Britain and Ireland during the spring and summer months to breed before migrating south to wintering areas in the Mediterranean. But, a study from Oxford University, the British Trust for Ornithology and the Max Planck Institute, has found the small warblers have expanded their wintering range northward across Europe and are now frequently found in Britain and Ireland in the winter months.
But, the study reveals, these birds are not breeders merely staying put. Instead, these wintering Blackcaps overwhelmingly originate from breeding locations across Europe, and are undertaking a highly atypical north-westward migration to our shores each autumn.
Benjamin Van Doren, who led the study as part of his doctoral research with Oxford’s Department of Zoology, said, ‘We were surprised to find stark differences in the birds’ anatomy and physiology depending on how often they appeared in gardens. For example, adult Blackcaps which frequented gardens were able to carry smaller fat stores because they know where their next meal will come from. This reduced weight makes them more agile and likely better able to escape from predators.’ MORE
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