I started off another spring days birding at Wyre forest this week. The plan was to spend the first couple of hours after dawn looking for Lesser Spotted Woodpeckers again. After last weeks visit I decided to adopt a different strategy. Rather than chase the drumming, when the bird has often moved on before you can get there, I decided to stay put near some promising drumming trees in a known territory and see what happened. Lesser Spotted Woodpeckers drum on dead trees primarily to communicate, using the hollow dry wood to create a resonant loud sound that travels far. This behaviour is used to establish territory boundaries and attract mates, acting as a substitute for birdsong.
This was partially successful as I heard a lot of drumming which I didn’t chase and was treated to two brief views. Again, I didn’t get any photos worthy of keeping. So here is the best I’ve achieved in the Wyre Forest from a few years back. Drumming mostly occurs in the hour after dawn and rapidly subsides such that by 08:30 it was pretty much all over.
Every year I like to take an early spring tonic in the form of a good dose of Ring Ouzels, the so called “Blackbird of the mountains”. They are early spring migrants local to me stopping off, as their name would suggest, mainly on hill tops to top up their fuel tank on their way to their mountainous northern breeding grounds. I’m lucky enough to be blessed locally with four fairly reliable hilltop locations including two, Bredon Hill and the Malvern Hills, which I can see from my house.
Giving their favoured hilltop location, going to see them also is an excuse to get some good exercise. No more so than the Malvern north hill which is a fairly strenuous 30 minute walk from the quarry car park. Three males have been fairly regularly reported around the north hill in the Malverns over the past couple of days so this was my destination for the rest of my days birding.
On the way up I met another birder who, rather discouragingly, told me that he and a number of other birders had not found them that morning. Whether by luck or good field craft, I strongly suspect the former, I located them fairly quicky on the hillside where they were feeding. Ring Ouzels are not particularly confiding birds and are easily spooked and flushed. Their hilltop locations don’t usually provide much cover and to add to this difficulty the hills were very busy with walkers, many with dogs, enjoying the early spring sunshine.
I approached them a couple of times but didn’t get closer that perhaps 100 meters. I was acutely aware that they were trying to feed and didn’t feel comfortable in continually disturbing them. Quite often when disturbed they would fly up into one of the small number of stunted trees on the hills, wait for the danger to pass and then continue feeding. I noticed a tree they were coming to fairly regularly and hid on the ground behind another tree comparatively close to it. After a long and somewhat uncomfortable wait they flew back into the tree and after a while dropped to the ground to feed around the tree. As luck would have it they were undisturbed by walkers and fed under the tree for a good 30 minutes when, of all things, a bouncy spring rabbit disturbed them.
Ring Ouzels spend the winter in Africa before migrating to breed across a very large range from the UK across western and northern Europe and northwest Russia. The plumage of the male of the nominate race is entirely black except for a conspicuous white crescent on the breast, narrow greyish scaling on the upperparts and belly and pale edges to the wing feathers. The bill is yellow and the legs are greyish brown. The female resembles the male but is browner and with a duller breast band.
There are three recognised subspecies. Birds seen in the Uk are normally from the torquatus subspecies group where the males are dark black with only moderate pale fringes. The subspecies alpestris occurs throughout the rest of northern Europe and differs from torquatus in that it has strong pale fringes which gives it a scaly appearance. I’ve previously seen very scaley birds on Cleeve hill in Gloucestershire such as this male below but whether this is an example of alpestris or just the natural variation in torquatus is above my pay grade to say.
One of the males had some leg jewellery but the one that really caught my eye was this one which had significant white speculation on its hood, something I have never observed before. My first thought was that this was perhaps a first winter bird which had not fully moulted into adult plumage but this really didn’t make sense as juveniles resemble paler brown female birds which, as far as I’m aware, do not show this type of plumage.
Here is a smart adult female from a previous outing a few years back.
So I concluded that this must be a leucistic bird. These birds have a genetic condition causing partial pigment loss, resulting in white patches or feathers mixed with normal plumage. Unlike true albinos, they usually retain dark eyes, legs, and bills, aiding their survival.
When I got home I did a little research and found that, although I’ve never seen one before, a small number of Ring Ouzels do exhibit white patches on their heads, along with pale edges to their wing and body feathers. Evolution can either happen continuously or discontinuously. In the former small changes in genetics provide some form of evolutionary advantage and hence slowly become dominant by natural selection. The discontinuous form happens when a major step change results in a major evolutionary advantage. As an example of the latter, a Cuckoo evolving to become a nest parasite with the resulting huge saving in energy usage is a revolutionary change, i.e it either lays its egg in the hosts nest or doesn’t, there is no in-between! Given there seems to be all forms of hood speculation from very slight to very obvious, this must be an example of a continuous change that results in no evolutionary advantage or disadvantage as it would either rapidly become the dominant form or disappear from the gene pool.
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