Ring Ouzel
Even today, birds offer a chance for ‘amateur’ researchers to make a significant contribution to science. Take the Ring Ouzel, for example...
Two men, and decades of their hard work, have given us a better understanding of this summer visitor
How do we know about birds? I mean, we read about them in books and on websites and in magazines like this one, and watch TV documentaries and YouTube videos, and hopefully take the advice of fellow birders. But where does that knowledge originate?
A lot of it comes from research projects and studies by organisations such as the BTO and RSPB, often working alongside academic institutions.
But a significant proportion has always come from the dedicated work of ‘amateur’ researchers, ordinary birdwatchers like you and me.
Birdwatchers like Vic Fairbrother and Ken Hutchinson, in fact. Their book, The Ring Ouzel: A View From The North York Moors, was published late last year, and records their remarkable 20-year study of the species on the moors and in the valleys close to their homes.
For many of us, Ring Ouzels are a fleeting pleasure, bringing a brief glimpse of the wild mountains to our lowland patches as they pass through in spring. But more of that later.
For Vic and Ken, they were always more than that.
Ken said: “I was interested in birds from when I was a boy. My father was a great naturalist, and I remember one time he took me on the tops above Todmorden and said ‘that’s a Ring Ouzel’, and there was this distant piping of a bird. And he said to me it was a sign that spring had arrived.
“Fast forward to the mid-1990s when I’d retired, and was looking for a species to study, and that thought came back to my mind. Because I have a love for the uplands, the high moors, it seemed the right thing to do.
“I had to find out if there were any Ring Ouzels on the North York Moors, as there was very little published about it at the time. One May day in 1998, I went up to Rosedale, near where I live, and walked along an old railway track. And, to my surprise, I found a pair of Ring Ouzels in the first gill I came to.”
Vic’s interest in the species came from a different direction.
He said: “I love walking on the fells, and I’d always been interested in survey work and been very active in BTO and atlas work. By a strange coincidence, the same
year that Ken started, I attended an upland bird conference at Durham University. There was a talk about a serious decline in Ring Ouzels in Scotland, and they said they might be starting a study group.
“In due course, I was put in touch with Ken – l lived on the north side of the moors, he was on the south – and that’s how the joint study began. You don’t know what you’re starting, of course – we didn’t set out to do a 20-year study.”
Detailed surveys
And so began what Vic and Ken describe as “a special kind of patch-work”, focusing on Rosedale.
“There was hardly anything known about breeding Ring Ouzels on the North York Moors,” said Vic, “just some info on passage birds. One of the things the newly formed Ring Ouzel Study Group did was to support an RSPB-funded national survey. General atlas surveys give a fair degree of accuracy, but not a total picture.”
The species had been assumed to be in fairly serious decline in the UK before 1998, and the dedicated survey in 1999 found 6,157-7,549 breeding territories, resulting in the species being Red Listed for the first time. Twelve years later a second survey showed that had reduced to 4,649-5,332 territories, with a decline in range as well as numbers.
Vic said: “Our study has shown ups and downs in terms of numbers, but they have remained fairly stable overall. There has been an RSPB-funded, professional survey in Glen Clunie, Aberdeenshire, and that had a bigger decline in that period, but then numbers picked up again.
“The Glen Clunie study enabled comparisons to be made between the two study areas, and there were found to be close correlations between dips and peaks in both studies that pointed to a national rather than a local problem. At the start, it was assumed the decline was a UK problem, but it has now been noticed elsewhere, such as Switzerland.”
Ken added: “Our study has shown how amateurs can help the professionals. Our work dovetailed with theirs, and Innes Sim at the RSPB obtained funding to look at migration problems. Our study fed into the broader national picture.”
So what are the threats responsible
for declines? Worryingly, both adult return rates and juvenile survival rates are problems, as is habitat degradation.
Vic said: “Studies show that, in the UK at least, they need very specific habitat – somewhere with good protection to nest in, in our case heather or on steep cliff faces, and short grass nearby, to forage for earthworm and insect food.
“So, some of the threats are threats to this landscape. The RSPB have been doing trial schemes on grazing levels. One at Geltsdale in Cumbria shows that lack of grazing stopped Ring Ouzels reaching earthworms, and they stopped breeding; while at Dove Stone in the Peak District there was the opposite, overgrazing, which removed nesting habitat.
“Brexit comes in here, as we don’t know what will happen, with talk of tree planting in the uplands. Planting in Ring Ouzel (or upland wader) habitat, or removing sheep, could have a big impact.”
Moorland studies
Ken explained: “Colour ringing revealed that fewer than 5% of juveniles return to breed the next year. Coupled with that is the fact that fewer than 50% of adults return (the average lifespan is three years). Put those raw numbers together and it doesn’t take much for a serious decline to set in.”
The North York Moors birds that the men studied form one of the UK’s smaller populations. Ken explains that they estimated 65 or so breeding pairs for the Moors as a whole, with anything from nine to 21 pairs in Rosedale.
Vic added: “The whole North York Moors population is isolated. Not so long ago, Ring Ouzels bred on Exmoor and on the Long Mynd, Shropshire, but they’re gone now, and the concern with the North York Moors population is that if it falls too low it might not be replenished.”
NOT SO LONG AGO, RING OUZELS BRED ON EXMOOR AND ON THE LONG MYND, SHROPSHIRE, BUT THEY’RE GONE, NOW
The men explain that climate change scientists predict that species such as Ring Ouzel will probably move upwards in altitude, and northwards, as the climate warms. Given that the North York Moors birds generally already breed within 100m of the summits, the threat is clear.
Ken explained that first brood survival rates are better than second, probably because earthworms are not so accessible in late June and early July. And delays to spring migration can mean that birds arrive on the breeding grounds late, and run out of time for a second brood, if first nests fail. Migration in spring 2021 seemed, on the face of it, encouraging. Larger groups of Ring Ouzels than normal were reported, and not always at regular stop-off spots.
Vic said: “There are two phases of migration. UK breeding birds arrive in the last week of March and first week of April, and Fennoscandian breeders about a fortnight later; so it can seem stretched.”
Ken added: “The first arrivals here are usually March 21-24, with the bulk arriving up to a fortnight later. British breeders tend to come up the west of country, with Fennoscandian birds come up the east. We did see some groups of 20 or so, this year, but I think it was a typical year, with weather blocking conditions, so birds stop halfway and get bunched up.”
Migration patterns
So why do Ring Ouzels migrate to southern Europe and North Africa, rather than just altitudinally?
Ken said: “Just before migration, they switch to eating berries, and on their wintering grounds in the Atlas Mountains or southern Spain they feed mainly on Juniper berries. Sources of nearby water are also very important – Juniper berries have a hard casing that the birds need to soften for digestion.”
While they could, theoretically, remain in the UK, the theory is that this would put them in competition with Redwings and Fieldfares, and resident thrushes.
Ken added: “Every year there are reports of birds overwintering. There was one near me the year before last, and Bempton had a male overwintering on the reserve, feeding on earthworms. It was probably a Fennoscandian bird.
“One of the risks at the moment is migration – if they can avoid that it might benefit them long-term, but the migration pattern is probably ingrained in them, and goes back to the last ice age.”
While the pair’s long-term study is detailed in their book, they continue to look ahead to new developments in Ring Ouzel research.
Vic said: “Tracking of Ring Ouzels has happened late, because they’re small birds. So far it shows they use the same routes in both directions, but one went over the Bay of Biscay, for example, so there are surprises. The importance of stopover sites can be looked at, too.”
You see? Once you get that thirst for birding knowledge, you can never know enough. We all owe the likes of Ken and Vic a big thank you for doing the hard work for us.
MIGRATION IN SPRING 2021 SEEMED, ON THE FACE OF IT, ENCOURAGING. LARGER GROUPS OF RING OUZELS THAN NORMAL WERE REPORTED...