Starling murmuration with partly cloudy sky and tree-lined background

starling murmuration cloudy sky trees background starlings evening roost birds thousands nature winter spectacle synchronized flight catterick north yorkshire orange black grey common sturnus vulgaris gregarious flocks red list swooping diving grouping hypnotising gather roosting wheeling stunts dusk behavior shapeshifting blackbird wonder natural world patterns swarming synchronicity shapes birdwatching uk