Today, Chris Baker from the RSPB on Arne's Winter Waterbirds

Wanna cry, wanna croon / Wanna laugh like a loon

When songwriter Yip Harburg wanted a lyric that was bewitching, eerie and freighted with topsy-turvy emotions he turned to the loon.

His song Old Devil Moon was helped along by the likes of Frank Sinatra, Tony Bennett, Judy Garland, Ella Fitzgerald and Miles Davis. And the loon’s mystical call, long a signature of the northern wilderness, found its way onto a jazz classic.

So prepare to be bewitched and to hum a tune if you see the bird, better known here as the great northern diver, swimming in the chop, from the shore at RSPB Arne.

You won’t hear the powerful call in Poole Harbour – that’s reserved for the summer breeding grounds in the north – but if you are lucky you may catch a glimpse of the bulky, dark body and dagger-like beak of one of the world’s most mystical birds.

A Gaelic name from the Hebrides buna-bhuachaill somehow encapsulates that mystery – not only does it cleverly echo the moaning call but the closest English translation, herdsman of the tide races, is a nod at how all the divers make light work of heavy seas.

Numbers of wintering great northern divers are nowhere near as high as last year but they’re there, along with black-throated divers, red-throated divers, great crested grebes, black-necked grebes and Slavonian grebes.

Rob Farrington, RSPB visitor experience manager at RSPB Arne, said: “Poole Harbour in winter has pretty much all the divers and all the grebes but they can be incredibly difficult to tell apart.

“The great northern diver is probably one of the easier ones because it is so chunky and it has a big beak, but telling the other divers and grebes apart is tricky.”

If it’s water birds you are after, winter in Poole Harbour is a place to be. Aside from the divers and grebes, there are redshanks, spotted redshanks, curlews, dunlins, grey plovers, little egrets, black-tailed godwits, bar-tailed godwits, not to mention the ducks... wigeon, teal, pintail goldeneye, scoter, mallard, and the odd eider bobbing in the harbour too.

Farrington added: “And we’ve still got plenty of spoonbills here, there are about 1,500 plus avocets in the harbour and there are about 1,200 Brent geese this year too.”

It’s a long list but one that doesn’t really do justice to the water birds you will find at Arne, there will have been some left off. (Tip to visitors, bring a good identification guide.)

If there is a common denominator, it is north. Many, if not all, of these birds will have headed north by the end of the winter to Scotland, Iceland, Greenland, Scandinavia, northern Russia, those places in the ‘crown of the world’ where the great northern diver is central to many myths about the Earth’s creation.

Quite where individual great northern divers go, along with many other water birds too, is still a bit of a mystery, even in this age of satellites and gadgets, as Farrington explains: “It’s difficult to tell really because you can’t easily read the rings of a seabird, and that’s if you can catch them to ring them in the first place.”

The other commonplace is life ain’t easy. With all those water birds about it’s no surprise plenty of birds of prey can be seen at RSPB Arne and around Poole Harbour.

Merlins, hen harriers, marsh harriers and peregrines can all be seen, by visitors and by the water birds themselves, who keep a beady eye on predators and take to the skies when they begin to sense danger.

Farrington said: “The water birds are an incredible thing to see anyway, but they really are spectacular if a bird of prey puts them up. Big flocks of birds wheeling in the sky to avoid predators, it’s great stuff.”

Harburg was thinking of the intensity of a love affair when he wrote Old Devil Moon. But may be another line from the song would resonate with those wheeling flocks of water birds trying to avoid predators?

You’ve got me flying high and wide / On a magic carpet ride / Full of butterflies inside

To keep up-to-date with all of the Winterwatch news at RSPB Arne, visit: Facebook: facebook.com/RSPBEastDorset Twitter: @RSPBArne Website: rspb.org.uk/arne