zondag 21 juni 2009

A wish that remains a wish... Badgers (Meles meles)

For years I wanted to see a Badger (Meles meles). Problem is, I live in the west part of the Netherlands and Badgers don't live there. Badgers look like they've been invented by Walt Disney, with their black and white stripes upon their head and their clumsy way of walking. Probably they are one of the most beautiful animals that one can come across in the Netherlands and who wouldn't like to see one? Well, I don't! Since I've found out, they don't exist at all! It's a plot! "Oh didn't you see the badger yet? Well, if you walk down this road, for about 5 miles and then you take the sandy road into the forest for about a mile, there's a big oak tree, with three arms. Walk for 200 meters to the east and you'll find a large sett (= a badger's den). There you wait until dusk. And then you'll see the badger" You walk down the road and all the people in the village are laughing their heads off...

I was one of these fools that still believed in the Badger and went to an area where it was believed to exist. Theo - the man that would guide me- knew a place. He showed me some pictures he took a few days before. Everything seemed good... Too good, I should have known... what a scam... ;-)

Yes, we didn't see badgers. But we did see some good stuff. The setting was fantastic.

A beautiful oak forest, without undergrowth and small but nicely shaped tree trunks. We waited until dusk and then the forest turned into magic. I got Clannad songs in my head of a Robin Hood television series I saw in my youth (by the way, the very best Robin Hood serie ever!). I saw something moving through the trees. At first I couldn't see what it was, but then it appeared to be a Roedeer with her calf. Beautiful, they moved through the forest and Theo and I could follow them with our binoculars without them noticing us. The next animal that appeared was a black male Roe deer, which came really close. Although I've seen hundreds of roedeers in my life, I hadn't seen them in this setting. I fantasized where the badger would appear, how it would walk and what it would do. But nothing happened....

I had a fever and and was thinking of the five miles I had to walk back. It wasn't a happy thought. But then we flushed a large animal, it appeared to be a large Wild Boar (Sus scrofa). The adrenaline and a little fear got me going. Especially when we stood between three tiny piglets. Very nice animals, but I was also thinking of it's mother, which was probably not that nice... We walked on. But then we heard the piglets again.. "oink oink oink.." Unbelievable but they were following us. When we walked a little harder, we were able to lose them. On the way back we crossed our path with some Red Deers, some young foxes and a few Nightjars. But the Badgers weren't our friends that night...

And it could have been so nice... (sorry for that music folks...)
http://www.youtube.com/watch?v=p96qYi8IfwM&feature=related
(if they existed off course..)

The rest of the weekend we spent on some other local specialties, like the Slow Worm (Anguis fragilis), the Adder (Vipera berus) our only poisonous snake in the Netherlands and some other stuff. Even without the Badgers this weekend was good!!!


zondag 11 januari 2009

Dusky Thrush (Turdus eunomus) in Belgium



Yesterday we (Frank van Duivenvoorde, Luuk Punt en me) left for Belgium. A couple of days ago, a Dusky Thrush was reported in Erezée in the middle of the Belgian Ardennes. The bird stayed, and beautiful pictures arrived also in the Netherlands. When Luuk called me if I wanted to join, I didn't hesitate: The Dusky Thrush was a lifer, views were apparently really good and the Ardennes is a very nice area. So I cancelled my other appointments (sorry for that, my friends!) and went to bed, to catch some hours of sleep. We left at 5.20 a.m. for a long drive to Erezée. A major part of it, we had to drive in the dark, temperatures were way below zero. It was years ago, since we had these arctic circumstances in this part of Europe. Especially when we entered the snow covered parts of Belgium, the temperature dropped. Our record was -16 °C. There was one luck however, there were no clouds and no wind. When we saw the sun rise, it was actually a quite pleasant day.



When we arrived in Erezée, there were already about 20 - 30 people present. Different languages were spoken, French, Dutch, German and English: We weren't the only twitchers that wanted to see this species. Many of our Dutch birdwatcher friends had also left for Erezée. Ridiculous if you think of it... without knowing of each other we met in a small place in the Dutch Ardennes. A place that probably no-one had heard of before... but there we stood, waiting for a lost bird to arrive in -15 °C.

It had chosen a small orchard with appletrees. One old tree had still a lot of apples on its branches. And about 15 Blackbirds, one Fieldfare, a few Starlings and one Mistle Thrush were feasting on these apples. Especially on the ones that were fallen below the tree.


Then all of a sudden the Dusky Thrush Turdus eunomus arrived. We had magnificent views on this beautiful bird, that originates from central Siberia and eastwards. Dusky thrushes are rare vagrants in Europe. Apparently it was the fifth record for Belgium, but the first since 1956!

The combination of very fine plumage elements made this a very nice bird. The wing pattern, the double breastband, the diamondshaped markings on the sides, it's supercilium, all fantastic! All these different tones of brown colours, wow! The crowd stayed calm, the bird showed off, the snow,... a small vacation in Belgium. All in all it was a fantastic twitch.

We drove through the Ardennes in the direction of the Dutch Province of Limburg. Near Herstal we saw the reported Iceland Gull Larus glaucoides. Inland Iceland gulls are rare and we had some short but good views. After a few minutes the bird flew off together with a couple of thousand Black Headed Gulls. We are quite used to large amounts of gulls, but this was really enormous.

The rest of the day we spent birding and enjoying the nice scenery in the Dutch Province of Limburg. We dipped out on the Eurasian Eagle Owl Bubo bubo on the Pietersberg near Maastricht. But had some magnificent hours at the Hamster nature reserve near Sibbe. This is a large agricultural reserve. Made for the last Dutch wild Hamsters Cricetus cricetus, but many other animals can benefit from this protected area as well. We saw hundreds of Yellowhammers, Linnets, Common Wood pigeons, Jackdaws and Rooks and in betweens these groups we found about 15 Corn Buntings Miliaria calandra. A speciality from this area, they have become really rare in the rest of the Netherlands. A few Northern harriers and splendid views of a hunting Merlin.



All locations and pictures of the birds can be found through http://waarneming.nl/ and http://waarnemingen.be/



A last picture from our very nice day. The scenery from a typical "Holle weg" (= hollow road) in Sibbe in Limburg. Frank and Luuk ahead of me walking towards the car.

vrijdag 2 januari 2009

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!!

vrijdag 5 september 2008

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

dinsdag 15 juli 2008

Montagu's harrier - Circus pygargus

In the North-east part of the Dutch province of Groningen is a small stronghold of a magnificent species: the Montagu's Harrier Circus pygargus. These harriers were quite common in the nineteenth century, but the habitats it inhabited (open dunes, moorland, reedbeds) changed and got apparently useless for the harriers. Above the changing landscapes came the DDT problems. Montagu's harriers feed on rodents and large insects, and the use of DDT as an insecticide took its toll on the harrier population. Apart from the accumulation of poisoness chemicals there were also no large insects left. The numbers of Montagu's Harriers declined in the Netherlands and by 1987 there were only 3 pairs left. Things didn't look very promissing.

By 1990, when everybody probably gave up on the Montagu's Harrier as a Dutch breeding bird, things changed unexpectedly. In that year the European Union decided to no longer subsidize the wheatfarmers in order to get rid of the surplus of wheat and to get a better and more natural wheatprize. Instead of subsidizing the farmers for their production they subsidized the farmers when they took agricultural land out of production. Since the wheatprizes were so low, the farmers could better set-aside some of their land and benefit from the European money. Unexpectedly this set-aside agricultural land, had an amazing side effect. Many species that were having difficulty in surviving in the barren Dutch agricultural landscapes, florished in this newly created mozaic. Two species that were never seen before breeding in agricultural land started to breed in the Oldambt area. One was the Corncrake and the other was the Montagu's Harrier. The area became some kind of surrogate Steppe area. But because this was off course still agricultural land, the birds needed some kind of extra protection. In order to provide the birds with this protection, a Foundation was created: Stichting Werkgroep Grauwe Kiekendief. They were succesful, numbers increased to about 40 breeding pairs, last year! the project co-operates closely with its German counterpart.

The project is really nice. Everybody seems to co-operate, from politicians, to farmers, to volunteers and to scientists. The birds are ringed, wing tagged and some receive a satellite device. The volunteers build nest-protectors and the farmers don't harm the nests. In order to keep people involved, they name some of the satellite birds after the farmers or the volunteers. The project gathered a massive amount of information about these beautiful birds. Read all about them on the website of the foundation: http://grauwekiekendief.nl/index_eng.php




The satellite tracked birds gave us more insight into their lives, especially during the time they were on migration into Africa. It all started with two females Marion and Beatriz. Read here about their sad but fascinating stories. Every satellite bird tells his or her own story, which makes it really personal and very interesting, more birds got a satellite device and I can advise you to read their stories as well. If this got your interest, there are more projects concerned with satellite telemetry of Montagu's harriers: http://malimbus.free.fr/trakindx.htm

My friend Vincent van der Spek, joined the project for an internship. He invited me and some other friends to help him with his project. It was mutual benefit, since we would be able to enjoy the Montagu's harriers and he would have some company and a car to drive him around. I'm still very thankful, since the two days I was able to visit him, were absolutely fantastic. And especially the first day, was one of the best Birding experiences I ever had.


One of the nesting sites
Nest protector

Vincent showed us that the Montagu's Harrier is colony breeder. Don't think of a colony like that of herons, but think of a couple of nests in the same wheatfield a couple of hundred metres apart. All kinds of interesting facts were told and seen in the field. We saw the adult males bringing food to the nests and females co-operatively chasing away a Marsh Harrier. What beautiful and elegant birds! We heard their calls, saw a young and tagged bird and enjoyed the landscape. Then when our survey time was over, Vincent had another surprise.


There was a nest to be ringed that afternoon and we were allowed to be present. Wow! That was a great wish. It was just as I hoped it would be. We measured, ringed and wingtagged 3 birds. Have a look at the pictures (from both days) and you probably know how I felt.


female of the second day.

The ringer: Erik Visser


The day wasn't over yet. There was a good wader area called Polder Breebaart. A few days before, there was a sighting of two Broad-billed Sandpipers and a Marsh Sandpiper. We (Ben Wielstra, Luuk Punt, Vincent van der Spek and me) had already been there in the afternoon, but then things weren't really promissing. When we returned in the evening, with the right tide, things were completely different, there were many, many birds. At least a thousand Dunlins and a couple of hundred Spotted Redshanks. We scanned the area and saw a few Curlew Sandpipers in breeding plumage, a few Red Knots and then Ben discovered a Broad-billed Sandpiper. We didn't have much time to enjoy watching it, because Vincent discovered an odd looking Golden Plover. It was indeed odd and after an identification discussion (small bird, long-legged impression, dark undertail coverts, barring on the sides, yes, ...dark underwings, ...) we agreed it was a Pacific Golden Plover! A bird that can look much the same as an American Golden Plover, with which it was considered conspecific in the past and as a Golden Plover, so we had to be careful with the ID. But everything was alright for this species. What a discovery and what a day!!

The second day I was with Kasper Hendriks, Rob van Bemmelen and Maarten Verrips. We weren't as lucky as the first day, but this was also a very nice day. We could join two ringing sessions of two different nests. But this time much more people were present. A nice thing was that the proud farmer was also invited. The wader area was however less succesful. We weren't there with the right tide, which did matter! I did see about 75 Common seals and a couple of thousand Common Shelducks, which was also nice.

The farmer, who owned the land where this bird hatched.

Common Seals at the Dollard.

The Montagu's harriers might be under pressure again. This year, for the first time in 18 years, there were hardly any lands set-aside. The European Union stopped subsidizing this out of production taking, since there is a shortage of wheat and other agricultural food products on the world market. This year will therefore be a very important year for the harriers. How will they cope with this change of land use? Will they be able to get enough food? And will they be able to adapt? Please contact the foundation if you like to support them!

zondag 13 juli 2008

Balearic Shearwater - critically endangered

Sorry for my low output lately. I just couldn't make time to write and also lost a bit of interest in writing (June is always a bit of a quiet period for birds in the Netherlands). But things changed completely yesterday!

My friends (Luuk, Frank and Ben) called me to go birding in the province of Noord-Holland. Their main goal was to try to get a view of a Balearic shearwater Puffinus mauretanicus. Problem with Balearic Shearwaters is, it takes hours and hours of watching over an empty sea to get a short glimpse of this bird. The species is really hard to get in the Netherlands. Not really promissing, certainly not when the weatherforecasts were also not really nice. I had plans visiting some Musea and said no to them. After an hour, fear took over me. Ben was quite convincing, Lucky Luuk was part of the team and although early in season it was the right time of the year: Saturdaymorning 5.20 a.m. I stepped in Luuk's car to visit Camperduin (the best place to see this species in the Netherlands!). On the way, clouds became darker and darker and there was heavy rain. When we arrived at the spot, there was no way we would go and watch this empty sea for hours in the rain. We decided to change plans and visit a sad grounded Eurasion Griffon Vulture in Wieringen. (our luck with the Balearic Shearwater would change later that day, please read on!)

The Eurasian Griffon Vulture Gyps fulvus, was discovered two days before. Probably due to the bad weather the bird had stayed here. Vultures need thermal vents to fly without using too much energy. It was a sad sight, the bird didn't move at all and looked more like a beheaded stuffed bird than a large fearcefull scavenger. A bit boring, but it was at least something.

The wheather changed a bit and things looked more promising. We went to Den Oever, where a few White-winged terns had been seen lately. There were loads of beautiful Black terns (it's closest relative). They were foraging in flocks, have a look at Luuk's weblog to see a picture of the Black terns: http://vogelverslagen.web-log.nl/mijn_weblog/2008/07/vaal.html
We didn't see the White-winged terns, however.

We visited some more bird areas (Saw a nice juvenile Little owl and some breeding plumage Sanderlings) and then we decided to have another try at Camperduin. There's a hut (without a roof though...) built as migration point where we settled ourselves. Within half an hour we were succesful! Incredible, I discovered the bird at really close distance, only about 150m away. We had splendid views, better than this you probably won't see a Balearic Shearwaters in the Netherlands. We followed the bird until we lost it behind the dike. We just couldn't believe it and we were really happy with this sighting.

To read something about their identification: http://www.noc.soton.ac.uk/gg/SWSW/id_guide.html (sroll down to the Balearic Shearwater identification article)

The hide:

The dike where the bird vanished (called Hondsbossche zeewering):

As I already said, Balearic Shearwaters are really hard to see in the Netherlands. The only place where you probably have a reasonable chance to see one is Camperduin. But only if you are willing to put time and effort into it. There's another thing, which makes it more complicated to see one: Balearic Shearwaters are rare on worldscale, and they become rarer and rarer everyday! The total population is probably about 2000 breeding pairs, they breed on the Baleares (Mallorca, Minorca, Ibiza, Formentera and Cabrera). Predation by feral cats and rats takes a large toll at the breeding grounds. After breeding the birds leave the Mediterranean Sea and forage in the Atlantic. Adult mortality is also unusually high, probably due to long line fishing. The birds live close to the shores, closer than other close relatives. They have learned to follow fishingships to profit from fish discards, but with long-line fishing this trait is not very profitable to the birds... Read this interesting article to get a better insight into the problems Balearic Shearwaters are facing: http://bycatch.env.duke.edu/species/balearic-shearwater
If things aren't changed the bird might go extinct within 40 years!

Although the birds become rarer, chances of seeing one in the Netherlands might paradoxically increase. The birds are actually cold water specialists. The cold waters are much more productive in food for the Balearic Shearwaters than the warm parts of the oceans. Since the temperature in the oceans is increasing due to Global Warming, the birds have to travel further north to get their food: http://www.birdlife.org/news/news/2006/09/balearic_shearwater.html

See also:
But things are probably more complicated than this and a lot of research is still needed:
For more overall information and some pictures:
http://www.birdguides.com/species/species.asp?sp=011074
and:

zondag 15 juni 2008

Tiengemeten, Kinderdijk and other bird areas - Views in the past and in the future.


Yesterday we left for Tiengemeten: a small isle in the province of Zuid Holland. None of us (Luuk, Frank, Ben and me) had ever been there, but we had heard some good reports of other birdwatchers about this place. Tiengemeten is an island in the Haringvliet. It is the last true island that is left of the Dutch Delta (a large delta where several large rivers end in the Northsea), all the other islands of the Delta are connected by bridges to the mainland nowadays. If you want to read more about the history of the island, read this nice and very readable report: http://islas.ruudbijlsma.nl/tgm_en.htm


Tiengemeten was bought by Natuurmonumenten (an organisation concerned with nature conservation) with aid of the Dutch Government. The main idea was to create a Nature island, with some low-profile recreation. (A fantastic choice since there were all kinds of plans with the island in the past, like the creation of a nuclair power plant or plans for a second airport for the city of Rotterdam). The new plans are immense. Not only is the entire area large (the total surface of the island and the area outside the dikes is over 1000 hectares), the plan also includes to break open some of the dikes, to relocate all inhabitants (the last farmer left in 2006) and in the future there are also plans to get back the tidal movements of the sea by periodically opening the sluices of the Haringvlietdam. This will mean the water will also become brackish again. We only visited the North-east part of the island. There was a strange historic atmosphere with the abandoned houses still present. The fields were gone, the ground lowered and a large part was inundated. The inundated fields were full of birds: about 50 Spoonbills, 30 Little egrets, 4 Black-necked Grebes, 1 summer plumage Dunlin, 4 Grey Plovers, about 10 Mediterranean Gulls, 12 Little Gulls (we even heard them calling), over 500 Black-tailed Godwits (not a good sign, these birds probably lost their nests), numerous Redshanks and several species of ducks.
But the 15 Black-winged Stilts Himantopus himantopus were the best treat of this island. Black-winged Stilts are rare in the Netherlands, to see 15 birds is even rarer. The birds were breeding, we saw at least 4 nests! Then we had to quit our visit, a heavy thunderstorm and rain came closer and closer and we decided it would be safer to leave the open fields and return to the visitors centre.



We took the little ferry and returned to our car.












In the meantime the weather had improved and we decided to continue our trip. We tried the Scherpenissepolder. A Marsh Sandpiper had been reported and we quickly found the bird. Areas like the Schakerloopolder, Het Stinkgat, Krammersluizen were visited. Het Stinkgat looked nice when we arrived. There were some waders present near the viewing point, but when we walked towards it, a group of bored cows decided to bully our day. They decided to take a walk and scare away the birds... On the right, in the picture you can still see the flock of birds flying off...

Yellow-wort Blackstonia perfoliata along the path to the hut of the Krammersluizen:
Kinderdijk:


Our last destinastion of today was Kinderdijk. Kinderdijk got worldfame by it's Dutch mills, but also have a look at the way it got its name (it's a nice legend!). Nowadays these mills are UNESCO world heritage. It's the only place in the world where you can see so many of these types of mills together and it therefore attracts many visitors from all over the globe. To help you out of your dreams: Holland is not full of tulips, we don't walk on wooden shoes and most of the old windmills have already vanished long ago. Nevertheless the mills and hydraulic systems are an important part of our history and it is a good thing this site got on the UNESCO list. I had never been to Kinderdijk before and I must say, I was impressed by the view of so many old windmills. We stood between two newly built houses next to a busy road and looked over the fields towards the mills. It was like watching through a keyhole into the past.

Our goal was not the mills though. A white-winged tern Chlidonias leucopterus had been reported on the ponds right behind the houses. The pond was filled with floating leaves of Yellow Water-lily Nuphar lutea and on these floating leaves there were nests of the closely related Black Tern Chlidonias niger. Black Terns breed in small colonies and prefer to breed on floating plants in fresh water marshes. Sometimes they breed on man-made small rafts, specially created for this species. In winter they stay in large flocks at sea in Western Africa. The numbers of Black Terns decline. In the breeding atlas "Teixeira R.M. 1979. Atlas van de Nederlandse Broedvogels. Pp. 182-183. Natuurmonumenten, 's Graveland" a couple of reasons are hypothesized: Most important reasons are probably the fact that marsh areas and agricultural grassfields were drained and waterlevels were lowered. Other reasons probably are the strong decline of the plant Water Soldier Stratiotes aloides, the decline of large insects, and increased watertourism. I can understand the watertourism problem; when we arrived there were two people fishing, their boat was very close to a nest of a black tern. The fisherman probably weren't even aware of it. The nests are not strong at all and a large wave would probably make it sink...
Just immediately after we parked the car, we saw the White-winged Tern. We were very lucky, since 2 minutes later a Marsh harrier (a bird of prey) arrived. All the terns were alarming and trying to get the harrier away from their nests. The White-winged Tern joined the other terns. But then when the Harrier flew off, so did the White-winged Tern without any obvious reason. We waited for about half an hour (and enjoyed the still present Black terns), but the White-winged didn't return. We decided to leave it, and went home.