Although graceful in the water, the diver is clumsy out of it. Their legs are set so far back on their bodies that on land they are forced to shuffle around on their bellies.
As a result, the species – which, in the UK, is found only in north-west Scotland and the Western Isles – must nest close to the water’s edge. This makes the birds highly susceptible to changes in water levels. If too high, nests are prone to flooding and if too low, adult birds may be unable to reach their nests when returning from feeding.
Breeding success was previously poor, mainly due to egg loss caused by flooding, with predators also a factor.
However, a pioneering project to recreate an ideal breeding habitat for the species has found remarkable success.
Conservationists devised the unique system of tethered floating nesting rafts, covered in vegetation, to provide stable breeding habitats and have partnered with landowners to implement them throughout the region.
Since the introduction of the raft programme in the late 1980s, the black-throated diver breeding population has rebounded from a low of 180 pairs to 240 pairs in 2012.
Stuart Benn, RSPB Scotland Conservation Manager, said: “Black-throated divers are the most stunning of British birds, a gorgeous, sleek combination of black, grey and white, with never a feather out of place. It is fantastic to see these charming birds successfully breeding on our lochs. This is a great example of how, through simple measures, we can give nature a home and have a huge impact on the success of a struggling species.
“Thanks to our partnership with landowners, we are able to provide a safe haven and the conditions they need to thrive.”
The black-throated diver (Gavia arctica) is a migratory aquatic bird of the northern hemisphere. In North America it is called an Arctic loon.