Chiming flocks have a fun time
Nothing excites the senses quite like coming across a mixed flock of foraging woodland birds. Eyes and ears absorb every sight and sound as the old adage about birds of a feather flocking together is dismissed in a flurry of wings and excited calls.
Exploiting food sources and gaining group protection are the driving forces behind passerines – the scientific name for perching birds – merging into vibrant mixed species flocks.
A lifetime’s birding has granted me many opportunities to watch such flocks at work in winter or during migration. I’ve had encounters with chats, flycatchers and sylvia warblers in Morocco and Israel, while the woodlands of Texas produced a kaleidoscope of colourful wood-warblers, vireos and tanagers freshly arrived from flights across the Gulf of Mexico.
Like their overseas counterparts, our tits, goldcrests, nuthatches and chiffchaffs also take advantage of forming flocks when conditions are harsh.
Looking for some exciting post-christmas birding, I headed to the splendid gardens of a local museum to seek out flocking behaviour in action.
Almost immediately, the twitter of longtailed tits filled the air. A family group of a dozen of these lollipop-shaped birds rippled through the bare branches of a beech tree as if they were acrobats leading a circus parade.
Seconds later, blue, great and coal tits took to the ring, each individual bird doing its own thing, checking under leaves and inside bark crevices for nutritious grubs.
Tiny goldcrests squeaked excitedly, comfortable in the safety of so many vigilant eyes. Soon something was creeping down a giant beech – a nuthatch. High above in the canopy, an over-wintering chiffchaff called loudly.
Over the next five minutes, the combined flock of more than 50 individual birds danced, clinging on leaves or catching flies on fluttery wings. Then they were gone.
The flock vanished from its circuit of the park as quickly as it had materialised.
Clearly there were more grubs to glean, more acrobatics to perform, more noise to make elsewhere.
Various tits checked for grubs as goldcrests squeaked excitedly