New Year

A selection from the birds, we (Bird ringing station Meijendel, near Wassenaar) caught in 2008. All the birds were measured, aged and sexed if possible and were then released with a ring with a unique number. We ring in the dunes of the nature area called Meijendel. This area is owned and preserved by the Duinwaterbedrijf Zuid Holland (DZH). On our ringing station we try to get an impression of the species and numbers that use the dunes the year round. This includes local breeding birds, after breeding dispersion, and autumn migration. We had a fantastic year, that broke all the records. For our total list please take a look at Trektellen.nl

If you wondered which species are on this picture, or already figured out, but want some confirmation, from left to right: Spotted Crake (Porzana porzana), Bohemian Waxwing (Bombycilla garrulus), Eurasian Wryneck (Jynx torquilla), Blackcap (Sylvia atricapilla), Thrush Nightingale (Luscinia luscinia), Lesser Spotted Woodpecker (Dendrocopos minor) and
Great Grey Shrike (Lanius excubitor).

I wish you all a good 2009!!

Wryneck - Jynx torquilla

Until last year, I had never even seen a Wryneck. I had tried to twitch it, but without succes. I missed birds, while friends had just seen it a couple of minutes before. And I had searched for them during Spring and Autumn migration. This species however stayed an enigma. Not only because I wasn't able to find one, but also because every birdwatcher in the Netherlands gets enthousiastic when they start talking about Wrynecks. What is it, that makes this bird so special?

First of all, it's rare in the Netherlands. Rareness makes a bird often more special. Simply because you won't get to see it very often and every time you do, it gives some extra excitement. This is probably a human trait, since human interest often increases if things are uncommon or rare. You'll also find this in economics or in art. Coals and diamonds are both allotropes of Carbon, but people get much more excited when they find a diamond then a piece of coal. And this also accounts for art, since true masterpieces are rare.

Wrynecks are Woodpeckers. They have, like other woodpeckers a very long tongue for grasping insects out of places that are otherwhise hard to reach. Their toes are placed zygodactylly (i.e. two toes pointing to the front and two pointing to the back) and their call is somewhat comparable to other woodpeckers. For the rest they don't look like them at all and are therefore placed in their own Genus. The Genus consists of two Species. The Eurasian Wryneck Jynx torquilla and the African Rufous-Necked Wryneck Jynx ruficollis.

Although Wrynecks are woodpeckers, they don't behave like them. They usually don't climb vertically on treetrunks, they don't excavate their own nest and they don't drum. If you are lucky to get to see this bird (otherwise take a look at my pictures), you'll easily find these behavioural differences in it's morphology. Most woodpeckers have a pointed tail with very strong tailfeathers. They use their tail for support when they vertically climb treetrunks. The Wryneck however, doesn't very often climb this way and therefore doesn't need such a tail. Their tail is rounded. It's bill doesn't look like that of the true woodpeckers, not a chisel shaped strong bill, but more that of an insect eating Passerine. Furthermore the Wryneck is the only woodpecker with a regular long distance migration. They winter in Africa and migrate every year. Some other species of woodpecker sometimes disperse over long distances, but they won't do so every year and they won't make the same distances as the Wryneck does. Other species of woodpeckers show small irruptions, when unfavourable conditions force them to move. But these shifts are uncomparable to the long distances that Wrynecks fly.





Wryneck... Strange name, isn't it? If you wonder why it bears this name, take a look at this small movieclip:

http://www.youtube.com/watch?v=LD52NLJw4Pk

You'll see a Wryneck wrynecking. It is twisting its neck in all directions. In many languages it bears a name that is pointing to this weird behaviour. In Dutch it is called "Draaihals" and the latin "torquilla" means turning. But why does it do this? Apparently the stretching of the neck and the turning make it look like a snake. It even makes a snake-like hissing sound. Wrynecks breed in old used woodpecker holes and if they are disturbed they can probably scare the predator with this behaviour. But they also seem to use it in courtship.

I was very lucky when my friend Casper Zuyderduin discovered this year a wryneck in Katwijk, since it was the first time I had a reasonable view of this bird. I had seen my first last year, but that was not really satisfying since it was on our bird ringing station and I had to leave the bird, because I was disturbing our nets by watching it and we had a small chance of catching it. So I was asked "friendly" to get into the hut. Off course we didn't catch and I was not as happy as I expected to see a bird so high on my whishlist. The Wryneck, Casper dicovered wasn't easy to find. At first we didn't find it and I made plans to never twitch a Wryneck again, but then suddenly Casper saw it again. And so did I, Magnificent! But things got even greater this year, when I was present when two Wrynecks were caught.

One was at the famous bird ringing station Castricum, where my friend Vincent van der Spek and I were to do our bird ringing exam for a Dutch ringing permit. I got to ring a Wryneck! Fantastic, but also a bird I had never ringed before and this didn't make my exam easier. Of course the identification was no problem, but the ageing was a bit harder. The pattern on the primary coverts was important to age the bird and this bird appeared to be a first calender year. It was an incredible day, with a lot of new ringing species, but because of all the excitement and the number of birds we got to ring, there was hardly time to enjoy the birds. The next day was therefore a fantastic second chance.

Vincent and I both got our permit. We were very excited and couldn't wait till we could ring on our own station (V.R.S. Meijendel). The next day we arrived at Meijendel where Maarten Verrips (one of our tutors) had already set out the nets and welcomed us. There were many many birds and we had to work very hard. Luckily Kasper Hendriks and our guest Engbert van Oort were also there to help. Then when numbers decreased a bit, Vincent and I walked a round to get the birds. We were joking and laughing a little and celebrated our ringing permit. Then ... a Wryneck!! Vincent got a Wryneck from the nets.. We walked on and unbelieveble, the next bird we got was a Thrush Nightingale!!! But that's a story I will write about later.

The Wryneck was beautiful. It looked like a moth or a reptile. At least something ancient. The cryptic colourpatterns were very nice. Now there was time to enjoy the bird. The sound, the feet, the twisting of the neck... We took some pictures and released the bird. It flew off on it's way to Africa!

I found this interesting blog about European woodpeckers, where you can read more about the wryneck: http://woodpeckersofeurope.blogspot.com/search?q=wryneck

CES Constant Effort Site - Bird ringing

CES, or Constant Effort Site is a specific method of bird ringing. The idea is to monitor birds over a long period of time, with standardized methods. If you keep record of the age and sex of the birds and if you also record recaptures (i.e. when you catch a bird, that you've already ringed before), you are able to tell something about the demography of the birds in your area. The ratio of adult and juvenile birds give an impression of productivity, the recaptures tell you something about survival and site fidelity. Off course the power of your reasearch is in numbers. Not only the numbers on your own location but also the numbers of the hundreds of other CES ringing locations in Europe. This large dataset could be a powerfull tool for monitoring population changes. I'm not going into more details about the CES methods and guidelines. If you want to read more about these things, please read the EURING guidelines for CES ringing in Europe (Pdf)

One of the important things in CES ringing is the ratio Adults:Juveniles. If you want to produce data for this ratio, you have to have knowledge about the plumages of the different age classes. Sometimes it's very obvious a bird is a juvenile: There are bird species that have a juvenile plumage which is completely different from their adult plumage. For example the well known Robin Erithacus rubecula: On the picture below you'll see a juvenile bird on the left and on the right an adult bird. The juvenile looks completely different, doesn't it? You could hardly believe that the spotted brown bird grows into a brightly coloured individual. The Pictures are taken at "Vogelringstation Meijendel" in the dunes of Wassenaar.

In those cases it's easy to tell the age, but you have to know how the juveniles look like, otherwise you might think you're dealing with a complety different or even unknown species.

There are also cases in which it isn't that easy to tell the age and you have to look for more subtle differences. Sometimes it might even be possible that those subtle differences don't exist and you have to do without an age classification. Some feathers (or all, depending on the species) get moulted during the season. When feathers are moulted, it might be more difficult to age the birds. Have a look at the Winter Wren Troglodytes troglodytes: On the left you see a juvenile bird, which lacks the white tips of the undertail feathers. On the right you see a bird that was photographed in October. It shows white tips of the undertail feathers. Is it then an adult? No, sorry, you can't tell. First calenderyear birds (1cy) moult their body feathers in the end of summer (so also their undertail feathers). Once moulted, there's no difference between the undertail feathers of adults and of juveniles.

So during CES you constantly have to be alert to make the right ageing decissions. As I help as a volunteer on the Bird ringing station Meijendel, I will try to show you more often what we are doing over there and how you could age, sex or identify different birds.

During CES, we spend quite some time around the ringing area, in the middle of a beautiful nature reserve. As a bonus for our efforts, we often get to see a lot of other nice birds, plants, mammals and amphibians. Today was really special, I got a magnificent view of two Golden Orioles (male and female) Oriolous oriolus. We heard the male calling all morning long. But getting to see them is something different. Orioles spent most of their time high up in the canopy. Deeply hidden between the leaves and branches of the trees. But if you're willing to put some time into it, there's a good possibility of seeing them. So I decided to wait and search the canopy. Then all of a sudden the male showed itself. It was singing completely free on a dead branch (I made a painting, so you get an impression of the splendor of this species). There we no leaves or branches blocking the view. It was absolutely marvellous! Then I even got to see the female. I was daydreaming of catching them on our ringing station, but off course this will never happen. Ah well... it's always good to keep something to wish!