8 December 2006
While summer brings the colour, song and drama of the breeding season, winter is a great time to watch birds flocking together, sometimes in spectacular numbers.
Safety in numbers
If you walk around a woodland in the winter you may be forgiven for wondering where all the birds have gone. In fact, there are likely to be plenty of birds about, but instead of being evenly spread throughout the area, several species group together and move through the woodland in a loose, mixed feeding flock.
You may be lucky, and suddenly find yourself surrounded by blue, great and coal tits, goldcrests and chaffinches, twittering and feeding hungrily in one small area. Enjoy it while you can - in moments they will have moved on.
By using your senses, especially by listening, you can improve your odds of encountering these feeding flocks. The birds keep in touch with one another using short, quiet 'contact' calls, which, roughly translated, mean 'I'm here - where are you?'
By sticking together, they improve their chance of survival, because together they are far more likely to spot a predator, like a sparrowhawk, before it's too late.
And so to bed...
Avoiding becoming someone else's dinner becomes even more challenging at night. Visit the countryside or city centre on a winter's evening and you are likely to come across a massive flock of starlings, wheeling and turning in the darkening sky, heading for a sheltered spot —an empty building, leafless tree, or a bed of swaying, yellow reeds.
It is fascinating to watch these huge gyrating bubbles of birds, spinning in the sky, like fish shoaling together to dazzle their predators. When the birds decide it is safe to, they shoot down in a dark tornado of whirring wings.
Other species can be seen moving to their night-time roosts—you may have noticed the steady evening migrations of gulls, commuting from their daytime feast on a rubbish tip to a reservoir or lagoon, where they will spend the night on the water, alongside ducks and geese.
Rooks and jackdaws gather in their hundreds in farmland woods. Pied wagtails sometimes roost in their thousands in the warmth of power station cooling towers.
Timing is everything
For an individual bird, getting the timing right can determine whether you live or die. If you leave your feeding ground too early, you may struggle to find enough food, but if you leave it too late and miss the flock, you risk being picked off alone by a bird of prey.
It is the failing light that triggers many birds to head to their night roosts. In poor weather, starlings may be seen heading off to bed far earlier than normal. The opposite can also be true, and on bright, moonlit nights geese may still be seen feeding, out on the frost-silvered fields.
Timing is also important if you want to see some of the UK's most breathtaking wildlife spectacles. Wintering waders, and other coastal species that feed on the exposed mud at low tide, use high tide roosts when the sea covers their feeding grounds.
Sometimes, these favoured areas of higher shingle or mud can draw in tens of thousands of birds while they wait for the tide to fall. To find out when high tide is, you need to check the tide tables for that part of the coast.
It is best to get into a good viewing position an hour or two beforehand, so that you can see the massed birds fly in, and to avoid disturbing them when you come and go.
Some high tides are higher than others. 'Spring tides' are the highest, and likely to drive more birds into the roost sites, especially if there is a low pressure weather system or an onshore wind. You don't need to wait until the spring, though: the term refers to the way the tide 'springs' up the beach!
Where to go to see flocking birds
RSPB nature reserves are great places to watch winter flocks. Here are just a few that you could visit this winter:
For woodland walks, try:
The Lodge, Bedfordshire; Nagshead, Gloucestershire; Inversnaid, near Stirling
To see flocking starlings, visit:
Marazion Marsh, Cornwall; Strumpshaw Fen, Norfolk; Conwy, north Wales
To watch thousands of gulls flying to their evening roosts, go to:
Snettisham, Norfolk; Haweswater, Cumbria
See congregations of rooks and jackdaws at:
Buckenham Marshes, Norfolk
To get a glimpse of pied wagtails, visit:
Radipole Lake, Dorset
To see spectacular numbers of wintering wading birds, go to:
Snettisham, Norfolk; Exe Estuary, Devon; Morecombe Bay, Lancashire; Belfast Lough, Belfast