Autumn bird migration over Poole Harbour
PUBLISHED: 23:07 07 September 2020 | UPDATED: 23:11 07 September 2020
(c) Martinpel | Dreamstime.com
The diminutive Goldcrest and Firecrest flock in their thousands to Dorset’s shores to overwinter
With so many unknowns still ahead of us as we slip into autumn, it’s reassuring that so many of the earth’s natural occurrences are still taking place. Take autumn bird migration for example. Here in Poole Harbour this has been going on since early July!
From the magnificent osprey to tiny willow warblers, thousands of birds have been leaving our shores for warmer climes back in Africa. But where you have departures you also have arrivals. October heralds the influx of not just a few birds, but many thousands from countries further north and east, choosing our less harsh climate to overwinter. Take the hardy fieldfare and redwing; this classic duo of October migrant thrushes travels overnight from Scandinavia to arrive on our shores as dawn breaks, desperate to feed on our glut of autumn berries.
However, in amongst these flocks of bulky thrush’s there are some diminutive companions (yes even smaller than willow warblers) which tag along on this long, dark and often dangerous journey. Possibly because of their size, its only recently been discovered that thousands of tiny goldcrests arrive here from northern Europe, crossing the North Sea to arrive in the UK. These minute gems are Europe’s smallest bird and can be found across the whole of the UK as a breeding species; however, each autumn we see a mass arrival from mainland Europe as they escape the plunging temperatures and settling here for the winter.
A visit to a Dorset headland at dawn in late October will see each gorse and bramble bush busy with newly arrived goldcrests as they search for food, calling constantly to each other and sheltering from the wind. With them, but in much lower numbers, firecrests travel these vast distances as well, which for birds that weigh less than 4 grams is quite remarkable. Firecrests are the more striking of the two, with their black, white and orange head markings and vivid green plumage, spotting them on an October morning is a joy.
We know these species are migrating at night as we pick them up on our night sound recording equipment deployed around the harbour. Each species makes a slightly different set of high-pitched calls as they fly through the night.
Finally, and although not technically ‘a crest’, another tiny green jewel arrives in the shape of yellow-browed warblers. Once a national rarity, these visitors from Siberia are now regular October visitors to our shores, with around 10-20 logged each year along the Dorset coastline. They also migrate at night but are seldom recorded during the hours of darkness, but their presence is often given away as dawn breaks. As they make land-fall they start their distinctive ‘tsoeest’ call from stands of sycamore trees.
So, next time you see one of these tiny moss-green beauties, don’t just admire the bird, consider just how far it may have travelled for your enjoyment!
Find out about birdwatching events here then book online or call 01202 641003.