Witness the spectacle of Great Crested Grebes performing their courtship ritual on the tarn at RSPB Geltsdale

A pair of Great Crested Grebes have been spotted on the tarn at RSPB Geltsdale, preening and displaying in the spring sunshine. These elegant water birds were featured on the 'freshwater'Great Crested Grebes, by Adam Moan episode of Wild Isles on Sunday evening, in which you can see them performing their elaborate courtship display, and it was a real treat to witness this in the flesh – or feather – here on the reserve.

Great Crested Grebes were hunted for their feathers in the past, leading them to become almost extinct in the UK, but they are now protected by The Wildlife and Countryside Act 1981 and their UK conservation status is green, as numbers have increased from the mid-19th century to 1996, after which little evidence of population change has been detected. They can be spotted all year round in the UK, apart from in the north of Scotland, and inhabit reed-bordered lakes and reservoirs, where they eat mainly fish and aquatic invertebrates. They are found along the coast in winter, though their duller winter plumage and long neck can make them easy to confuse with divers and other grebe species.

Great Crested Grebes, by Adam MoanAs we have seen from the pair on the tarn at Geltsdale, Great Crested Grebes engage in graceful and elaborate courtship rituals, in which they can be seen rising vertically out of the water and shaking their heads. They also make a ‘mewing’ sound, perform synchronised swimming, preen, present each other with weeds and fan out the feathery ruffs around their necks. It is hard to believe that a bird which is so graceful in the water can be so clumsy on land – but the placement of their feet, far back on their bodies, makes Great Crested Grebes ungainly on solid ground. They are expert divers, swimming or diving rather than flying most of the time. The chicks can often be seen riding on the backs of the adults, sheltering in their plumage.

The largest of the grebes, at 46 to 51 cm long, with a wingspan of 85 to 90 cm and weighing up to 1.5kg, Great Crested Grebes have marked changes in their summer and winter plumage. In winter they are black on top with cream or white feathers underneath and a long, white neck, while in summer they are brown on top with orange feathers underneath. They still have white necks in summer, but with a brown and orange crest on top of their heads and an orange ruff around the top of their necks. In both seasons, they have red eyes and a pinkish bill.Great Crested Grebes, by Adam Moan

Great Crested Grebes nest in loose colonies or by themselves, making their nests on a floating platform of plants which is anchored to vegetation or weeds underwater. The females lay three to five cream-coloured eggs, which she covers with algae when she leaves the nest to feed, meaning they slowly turn chestnut brown. She incubates the eggs for 25 to 30 days, then, when the chicks are born, both parents feed them until they fledge (at around 70 to 80 days after hatching).

Check out the freshwater episode of Wild Isles on BBC iPlayer to see footage of these beautiful birds in action – or head down to RSPB Geltsdale, where you might just be lucky enough to spot them on the tarn.