A full version of this article appears in the magazine.

 

The ring ouzel (Turdus torquatus) is one of the classic birds of the Welsh uplands. Its melancholy piping song is evocative of the more craggy areas of our uplands, and being one of the earliest of migrants, it is the bringer of spring to the hills. Unfortunately it is also in serious decline, the reasons for which are unclear.

 

Ouzels arrive back in Wales from their wintering grounds around the Mediterranean and North Africa in March. Nesting territories are often in areas of mixed habitat containing crags and gullies with scattered bushes and trees commonly at heights of 250m to 350m or more. Foraging takes place in areas of short grazed turf for invertebrates where earthworms were found to be an important part of the diet during the spring. Later in the summer berries, especially bilberry, become a more important component. Eggs are laid in a grass nest, very similar to a blackbird’s, and a clutch size of four is the most common. Two broods are often raised keeping the birds busy into the summer. Southward migration starts in August and continues into October, with most birds arriving in the wintering grounds from late October onwards.

 

The main wintering grounds, although ringing recoveries are few, appear to be the hills of North Africa, especially the Moroccan Atlas. Birds will move through the Pyrenees, and often linger in the southern Spanish hills before crossing into North Africa. In the Atlas mountains birds are found in the considerable areas of Juniper forest at heights between 1400 and 2000m, where juniper berries are thought to be an important part of their diet.

 

Two races of ring ouzels breed across northern Europe, and their wintering ranges overlap. A third race breeds and winters in Asia Minor. The nominate race torquatus has undergone significant declines in its breeding numbers and a contraction in its range across the UK, while the Fennoscandanavian population appears, from observations of migrating numbers of birds, not to have declined, although published breeding surveys are few.

 

Welsh breeding ring ouzels have been in decline at least since at least the 1970s. Records from county bird reports and contacts with ornithologists suggested a population of 450 – 500 pairs in Wales for the 1980s. A sample survey of the UK in 1999 came up with an estimate for Wales of 293 – 392 pairs. A resurvey of a large number of the 1999 tetrads in 2006 showed a 69% decline in occupancy since then.

 

Various reasons for the declines have been suggested, ranging from declines in habitat quality and food supply in the breeding grounds and wintering grounds, hunting pressures on the migratory birds and climate change. It is unclear which of these possible reasons are causing the declines, and it is quite likely to be a combination of all of them. We need further studies of the ouzel, particularly post fledging and in the wintering grounds, to help to begin to understand these causes. Unless we can address at least some of the reasons for the decline, the future of the ring ouzel in Wales looks rather bleak at present.

 

Mick Green is a Director of Ecology Matters.