Recently it has been discovered that Black Larks, living on the Eurasian steppes in Kazakhstan, transport dung to their nests to build large 'pavements' . Weird and almost dirty behaviour, but what is the use of it? This spring a team of researchers from the Universities of Wageningen and Münster and the Association for the Conservation of Biodiversity in Kazakhstan (ACBK) will try to answer this question, doing fieldwork in the Korgalzhyn area in Kazakhstan. On this blog we will post on our findings and adventures.

Monday, 23 September 2013

Upcoming presentations

As stated earlier we will give talks on our findings on the Annual Conference of the Deutsche Ornithologen Gesellschaft in Regensburg, Germany on Sunday 6 October (in Englisch). On the 30th of November we will give a talk on the Annual Day of Sovon in Ede, The Netherlands (in Dutch). For a short introduction to the topic, please visit the site of Sovon and of course have a look at other presentations as well.

For the presentation in Sovon we made a short teaser as well. It is in Dutch, but it will give some impression on how it was in the field (don't forget to put it on HD-quality):

Wednesday, 28 August 2013

Back in the office

After a nice field season in Kazakhstan, we're all back at home. Johannes and Thijs have been working together on the analysis in Münster and are almost finished! Now the last parts of the analysis will have to be done and then the writing can start. We have a lot to write about, so it will take some time. If you are curious about the (first) results, please visit us at the DO-G Annual Conference at the University of Regensburg, Germany (2-7 Oktober). We will give a presentation on Sunday afternoon (6th of Oktober)! Another talk is planned at the 30th of November on the Annual Day of Sovon, the Dutch Centre of Field Ornithology in Ede, The Netherlands.

Next to the analysis of the data, we have started a new experiment. To see whether dung has an effect on the nest temperature, we have created artificial nests with plastic cups. We've placed these cups in the soil. We've placed dung around some nests and nothing around others. In this way we exclude all other factors such as vegetation. To measure temperature, we've placed the temperature loggers in these cups for three days, as we did in Korgalzhyn. We'll see how it goes!

Johannes and Thijs are analysing the data. Johannes is very pleased with the results!
We've collected fresh horse dung from the local riding school. As it was fresh, we had to dry it.
The roof of the university building is suitable for experiments. Here we have put trays of soil with the artificial nest cups in it.
An this is how the artificial nest cups with dung look like. The loggers are placed in the middle of the cup.

Saturday, 15 June 2013

Nests in all sizes and colours

We are approaching the end of our field season here in Kazakhstan. Most Black Larks are feeding fledged chicks or have given up nesting after several failed attempts. However, we still have a couple of nests active and even sometimes find more nests. We are now at 92 nests, not our target, but still not bad at all. Also, we repeated the trampling experiment a couple of times. Not a clear pattern in that yet, but we will try it some more times, we also like to work with the cows!

Not only Black Larks are nesting here in the vast amount of steppe. Numerous species, in Dutch many with ‘Steppe’ in their names, benefit from the huge amounts of insects dwelling on the floor or flying in the air. On their turn, raptors love to hunt on those species. It is therefore not surprising that we incidentally find nests of other species than Black Lark.

Already a time ago we found a miniature Black Lark nest, it belonged to a Greater Short-toed Lark. Although it was the only nest that we found (we are not really looking for them), it was surprising that also around this nest we found some pieces of horse and cattle dung! Not only the nest looked like a miniature Black Lark nest, but also the eggs and the chicks were minor versions of their bigger black brothers. We checked the nest a couple of times and it was eventually successful. We also found two Skylark nests. The chicks were not yellow-sandy brown as in Black and Greater Short-toed Larks, but black. Around these nests we didn’t find collected pieces of dung, but pieces of wood and dry clumps of earth were scattered around the nests. Collection behaviour is certainly not new in larks, for example Shore Larks collect small stones. Therefore, results of our project are very likely to hold for a broader spectrum of species than only Black Larks.

On a free afternoon we went to a large lake close to Korgalzhyn. There we found a pair of Pallid Merlins flying around us. There were only two trees, or more to say tall bushes, in the close vicinity so finding the nest wasn’t that difficult. We both agreed, we would like to have a nest there as well: on the border of a cliff on the edge of a large lake with views to beautiful sunsets every day! That day we found two eggs and later we found four eggs.

Today we went south, just south was the aim. At our picknick location (well.. just on the track) a pair of Steppe Eagles was present. Sometimes we could see white balls of fluff peeking over the edge of a shrub. Three beautiful youngsters were watching us whilst a stock of four Little Ground Squirels were waiting on the edge of the nest to be eaten. Both of the parents were watching us from the high sky, so we took some pictures and left again. Amazing how these birds are so exposed to the changeable weather here (we had some severe thunderstorms yesterday and last night). 

Nest of Greater Short-toed Lark. It is basically a miniature Black Lark nest. On the left side of the nest some collected dung is visible. The extent Black Larks collect dung seems however to be unique.
Nest with view on the lake. Merlins often use old nests of Hooded Crows.
Nests of Steppe Eagles are often as exposed as this one. Height of the nest, barely to the knee.. On the edge a fresh stock of Little Ground Squirels. 

Friday, 7 June 2013

The silvery sea: steppe in June

With the start of the month of June, summer has officially started in Kazakhstan with temperatures nearing the 30C. The steppe is now a waving sea of silvery feather grass, with a colourful mix of different flowers in between. Grasshoppers and cicades are chirping in the grass, but above all this is the loud high pitch buzz of a million mosquitoes.

Most of the Black Lark nests we found in May are now successful, which means that the chicks have fledged. Although we don’t always encounter the fledged chicks around the nest, it becomes clear that the nest is successful when it is sort of trampled by the big chicks and fledgling droppings lie in and around the nest. Sometimes we also see the fledglings themselves, jumping between the grass and making short gliding flights low over the ground. While driving over the steppe, we see many of these fledglings, of Black Larks as well as Skylarks and Greater Short-toed Larks.

In this region the Black Larks prefer abandoned arable fields to breed in. In these areas there is a large heterogeneity in microclimates: large tufts of grass give shade and shelter, bare patches serve as insect hotspots. In Soviet times large extents of steppe, not comparable to European standards, have been ploughed and turned into arable land. After Kazakhstan became an independent country these fields were more and more abandoned and are slowly turning back in steppe again. As said, these fields are preferred by Black Larks, so it is not necessarily a bad thing. Recently some of these abandoned fields are being used again. Last autumn a formerly abandoned field (5 by 2.5 km) has been ploughed in preparation for this spring sowing season. However, the Black Larks kept trying to nest here. As the season was cold and wet, the fields were only ploughed and sowed from the beginning of June, hereby destroying the current nests. Of course this is a sad thing, but it is also the harsh reality and a result of a higher demand of wheat for bread. On the other hand, this field will be essential in the survival of the male Black Larks that stay here in winter and maybe the field will once be abandoned again. We hope that the larks will try to make a new nest, but it might be that the breeding season is already too short for another breeding attempt. We will see how it goes!

Bird migration is coming to an end, but there are still many interesting birds around. Thousands and thousands of Red-necked Phalaropes can be seen on the small lakes in the area, looking like small flies on the water. The lakes contain many interesting breeding birds, including White-headed Ducks, Dalmatian Pelicans and Flamingo’s, but also smaller birds such as Paddyfield and Great Reed Warblers. On the shore of one of the lakes we found a nest of a Merlin, of which the very pale subspecies pallidus occurs here. We also saw another nice vagrant bird for the area, a Corn Bunting singing on one of the power lines. 

Black Lark chick hiding in the grass. They will be fed by their parents for approximately another 2 weeks after being fledged.
This is what we call 'the valley of 1000 males'. It appears that many bachelor males stay here to forage, show off and take a sun bath. Unfortunately very few females here..

Flowering feather grass  (stipa) has a typical silyery colour. Currently they start to flower and turns the steppe in a silvery sea.

A fledged Skylark

Saturday, 1 June 2013

Watch your step!

Do cows look where they put their foot, and will they avoid their own dung? And might this be a reason for Black Larks to use dung around their nests, to save it from trampling? These are the questions we want to answer by doing our so-called ‘trampling experiment’. As we showed in our last blog post, we made over 200 clay ‘cookies’ to be put in and outside dung piles in a grid, after which we let a herd of cattle graze in the grid.

With the help of the local Kolya on horseback, we managed to let a herd of cattle (91 cows) graze in our 1 hectare grid. Instead of driving them trough the grid, we wanted the cattle to take their time in the grid. We expected that in this way they will be more attentive where they step. The cows took their time in the grid while we waited, relaxing in the grass. After an hour we slowly drove the cows out of the grid and counted the result. About 10% of the cookies had been trampled, and by far most of the trampled cookies were the ones places on bare soil, so not in dung piles. We will definitely repeat this experiment, but for now it seems that cows are careful not to step in their own dung!

Already for some time we are placing temperature loggers in and outside empty nests (either predated or successful) to compare the nest temperature with the outside temperature. This week we took this one step further by adding dung pieces to the side of the nest and repeating the measurements. In this way we hope to get a better idea of the effect dung has on the nest microclimate.

During May we were lucky to have Gera with us one the project, who was an enthousiastic field worker and provided us with essential help for contact with locals. Yesterday she went back home, to continue working on a project on bird victims due to power lines. Thank you very much, Gera! Thijs and Thomas still have a month to work on experiments and find nests – up to the 100!

Most nests have 3 to 4 eggs, but this nest surprised us with 5 eggs!
While the cattle grazed, we could relax

Cowboy Thijs
Kolya helped us with getting the cattle into the grid, many thanks!
And another team picture :)

Sunday, 26 May 2013

Clay cookies

With two experiments already running, we are now making a headstart with the trampling experiment. With this experiment we want to test the hypothesis that cattle do not step in their own dung while grazing. For Black Larks this would mean that using dung around their nest would reduce the chance that their nest is being trampled. For the experiment we will slowly herd a group of cattle trough an area in which we placed fake nests, which are places either in dung piles or on bare soil.

For the fake nests we were planning to use small balls or eggs, made out of papier maché, as we showed in one of the earlier blog posts. Strong wind is however a constant factor here on the steppe, and these fake eggs would probably quickly fly off as soon as we would put them on the ground. Therefore we thought of a different material for fake nests, namely clay! Yesterday we moulded 200+ clay ‘cookies’ more or less the size of a Black Lark nest. We baked them at 35 degrees on the car for about two hours and now they are ready to use!

Making the cookies

Drying them on the car, 220 in total

This Greater Spotted Eagle flew over our heads. It's a late migrant or a rare summer visitor.

Wednesday, 22 May 2013

Being a good mother in changeable weather

The weather is rather changeable, now we have windforce 6-7 and sometimes rain and yesterday we still had nightfrost. However, we also had quite warm days. Higher temperatures are beneficial for the Black Larks, however, the anti-kamari (insect repellent) is then very much needed! But no complaints as we now have 69 nests! The finding strategy has slightly changed now. Before we flushed females with the car by driving over the steppe and steppe tracks. Now we regularly find males and females with insects in their bill, a clear sign that they are feeding their chicks. In a matter of time they will fly to their nest and take off without food. Then the nest is rather easily found. With more and more nests having chicks, the number of successful nests are also increasing. For us, a nest is successful when the chicks have left the nest. We are unfortunately unable to see whether chicks survive leave the nest.

In an earlier blog post we wrote about the Ibuttons (temperature loggers) in the nest while the female is incubating. This is doing fine now and we have put loggers in 28 nests. We already see nice incubation patterns, but also strange things. For example in the morning of 12 May there was heavy rain. During the rain all the females stayed on the nest (good parenting). After the rain, when the females must have been soaked, all birds with loggers left the nest for about 1.5 hours! The need for foraging apparently was very high. During normal days we see different strategies. Some birds leave the nest for a long period in the early morning and in the evening, some birds only leave the nest for shorter periods. Very interesting stuff to look into!

Another way to see whether dung is beneficial for the microclimate we have put 12 loggers inside left (predated or successful) nests and 12 loggers just 30 cm outside the nest. In this way we see how the microclimate differs between the cups and a random spot outside the nest. Preliminary results are that the minimum temperature is about 2 degrees higher in nests than outside the nest and the maximum temperature is 7 degrees lower in the nests. Both is beneficial for the female, eggs and chicks. We do not know the main cause behind this buffering effect yet.

Then a short note on the other things than Black Larks. We keep our eyes open during the fieldwork and afterwards. In this way we found Caspian Plovers on migration (rather scarce here), many many White-winged Terns and Little Stints and the Ruffs are becoming very numerous. Also, there is a nice group (approx. 300 ind) of Rosy Starlings around the village. The most stunning bird we saw was a male Crested Honey-buzzard on the 16th, which was only the second record for this area or more to say Central Kazakhstan. More to follow soon!

We can imagine that people are also interested in how the non-project things happen. Well, we all stay in so called homestays, so at home with locals. Here, we are adopted as family and provided with good local food and the occasional banja (sauna). Thomas and Thijs are living together with Timur and Ruslan. Ruslan is the project coordinator on Sociable Lapwings (ACBK), from which we get much assistance on logistics and information about the use of dung in Sociable Lapwings. Timur also works for the Sociable Lapwing project and also works at the Korgalzhyn Nature Reserve. Gera is staying in another homestay with Boris, who works at the Korgalzhyn Nature Reserve and there a lot people from the Sociable Lapwing project stay for one or few days. 

Nest attendance of one nest during one day (12th of May). In the morning she leaves  the nest for a long time (after the rain), in the afternoon she leaves the nest for only short periods. To get through the night, she leaves the nest again for a long period before the sun sets. 

Group of Rosy Starlings in the garden of the place where Gera stays

Lunch in the field!
We are still happy :)

Adult male Crested Honey-Buzzard

Monday, 13 May 2013

Already at 50% of the target

We first want to kick of with the good news: we already found 49 nests and with 100 being the target this is almost the half. However, nest finding becomes harder and harder as the vegetation grows very quickly and the temperatures are in general rising. In general, because we unfortunately lost three nests due to frost in the night, very sad but it happens. The females of these nests will try it one or two more times. The same holds for all the nests that are predated, which is very common. About 50% of the nests are currently predated and we haven't had a succesfull nest yet, but that might be expected tomorrow. This is somewhat later than usual, but this year is an unusual wet and cold year.

We have two main study areas around Korgalzhyn and it means that we drive for about 80 kilometers over the steppe tracks each day, the scale is quite coarse here. We have an old Soviet state farm map where all tracks are drawn. It looks like a normal agricultural infrastructure, however the fields are 3 by 3 kilometers large. We use a Lada Niva from the ACBK for our fieldwork, a great car for the steppe! Although we sometimes have to tweak it a bit to make it work, it does a great job on the bumpy field rides.

A few days ago we dug 80 pitfalls in the two study areas. We do this to see if the dung around the nest is collected is beneficial to the amount of insects (mainly beetles) around the nest. If this is the case, females don't need to leave the nest for a long time and far distance to (shortly) feed. Therefore we paired the pitfals: one in a existing dung pile and one 5 meters away from that dung pile in the bare soil. In 2 weeks we will collect the pitfalls and count, indentify and weigh the insects.

And then, we are not always in the field and sometimes we are unable to go onto the steppe due to rain. In that case we spent some time birdwatching in the village or the near surroundings. Currently the Siberian Chiffchafs are replaced by Greenish Warblers (very numerous) and we see many many Lesser Whitethroats. Already for a few days there is massive migration of White-winged Terns and we had one day of massive migration of Black-winged Pratincoles. Everything is a bit late, but that doesn't matter to us, we have the time. This morning we saw one of the predators of the nests: a steppe polecat, we often see foxes as well. We also see many birds of prey, mainly Pallid Harriers, but also quite a few Short-eared Owls and sometimes Steppe Eagles. This year seems to be a good year for voles, which is good for the harriers and owls.

Male Black Lark

Chicks of about 6 days old

Female stays on the nest for only the last moment. When she flies of she will try to fool us by pretending if she is hurt. Just like many waders.

Tulips make place for Lillies. In the background our Lada Niva

Pallid Harrier, photographed from the car at 40 km/ph. It seemed to play with us!

Sunday, 5 May 2013

First week

Nest searching (and finding) has started! This week we all arrived in the village of Korgalzhyn, right in the middle of the Kazakh steppe and the Black Lark’s breeding area. We directly started of finding nests, since the Black Lark breeding season has already started. To the steppe!

The steppe is often described as an endless sea of grass, which implies that it is very monotone. Although endless, the steppe is far from monotone. Currently the wild tulips are flowering and color the steppe with yellow, white and pink flowers. Orange tulips are rare and finding one will bring happiness for the rest of your life! We already found some orange ones, we hope this will give us luck in finding nests.
Black Larks are ground breeders and make deep cup-shaped nests (7 cm deep) in small scrapes in the soil. These nests are often located next to tufts of grass. The female scrapes out the nest, then adds small pieces of grass as lining. Often she adds pieces of dung as a pavement. During this study we want to find out why the birds do that.

Finding the nests is a time consuming business. In an old Lada Niva, we drive across tracks over the steppe. Black Larks often nest close to these tracks, and by driving we hope to flush the females from their nests. When a female flies off, we start looking for the nest on the spot she flew off. Sometimes we indeed flushed her from the nest and the nest is quickly found, but often she was either foraging or doing something else and finding the nest requires a bit more luck. So far we have found 22 nests with eggs and 13 nests which were still in the building phase. These latter nests might be used, but the birds might also decide to build a new nest somewhere else.

Once we find a nest we note down the location, the number of eggs, and data on the surrounding vegetation. Also we count the number of dung pellets and the direction in which the dung pavement is build. Dung might help to protect the nest against cold wind. If dung buffers the nest against the cold, this might have effect on the time a female can be off the eggs to feed. For this reason we want to keep track for how long the female leaves the nest in between incubation. We measure this using temperature loggers placed in the nest. We modified Ibuttons (as you can read in our last blog post) to fit on nails. We push a nail trough the nest into the soil and put the Ibutton on the nail with Velcro. In this way the Ibuttons fit snuggly on the bottom of the nest and the bird is unable to remove them. 
Next to black Larks we keep our eyes open for other birds. Bird migration is still in full swing, with hundreds of Yellow Wagtails (subsp. beema) and large numbers of others birds, including one of the largest fall in recent years (according to the local birders) of Lesser Whitethroats , Siberian Chiffchaffs, Common Redstarts and Wrynecks.

Female Black Lark

Demoiselle Crane

Eurasian Wryneck

How the buttons fit in the nest. We now fit the buttons under the lining

Huge fields of wild Tulips

Huge fields of wild Tulips

Enjoying free time

Friday, 26 April 2013

Few days to go - equipment modifications

All is set! Equipment is ready, the visas have been arranged and within a week we'll be searching for Black Lark nests in Korgalzhyn, Kazakhstan. Johannes leaves a bit earlier and will meet Ruslan and Gera in Astana on Saturday. Thijs and Thomas will follow on Monday.

We did some interesting modifications on the equipment. The Ibutton temperature loggers we use to investigate incubation patterns and a possible isolating effect of dung are tiny (about the size of a penny or a 5-cent-piece, 16 mm) and very light. No chance that we would find them again in the steppe if the bird decided to remove it, and why wouldn't they. The larks for sure are capable to remove it, as carrying pieces of horse dung is not a problem for them! Digging into the literature we found some clever ideas to overcome this problem. What we now did (at least for one temperature logger for the moment) is to attach Velcro to the top of the button and to the top of a 16 cm long nail. We will push the nail into the soil beneath the nest, so that only the button sticks out. For sure the larks will not remove it now, at least that's what we hope. By using Velcro we can easily detach the buttons to be able to read them more easy.

Ibutton temperature logger with velcro

They fit snugly to this nail!

We were wondering if the metal of the nail had an influence on temperature measurements, so we tested temperature logging with loggers mounted on nails versus loggers put on the soil. There seems to be a small temperature buffer effect of the velcro/nail combination when compared to loose Ibuttons, i.e. temperatures were approximately 0.5 degrees higher when using our construction. So we decided to mount all Ibuttons on nails, also those that are used outside nests. In this way the buffering applies to all Ibuttons and won't cause any problems in comparative analyses.

The green and blue lines (which largely overlap) are temperature curves from loose Ibuttons
put on the ground, the red and purple lines (also a large overlap) of Ibuttons attached to nails
 with velcro. As you can see, the temperature logged by Ibuttons on a nail is about 1° celcius higher,
a little more than the variation expected in these Ibuttons (half a degree).

For our planned experiment that looks into whether dung helps to avoid nest trampling by cattle, we would need to use an aweful lot of eggs! Using chicken eggs might be a good idea, but this is very wasteful. That's why we decided to try something with small (water) balloons and papier-mache. Easy to make, low costs, and no eggs are harmed in the process. Here the first try-out: They are pretty solid but still easy to "trample". Now we only need to make sure they are not blown away by the wind! We also discussed using plasticine eggs, since this material is heavier and can be molded / re-used more easily. It does increase the costs, so we might stick with the idea of using papier-mache eggs.

The papier-mache eggs before...
...and after a herd of students passed trough!

Using small wooden sticks to pin the "eggs" into the soil so they are not blown away.

Friday, 12 April 2013

More funding received and publicising our project

We recently heard that the Deutschen Ornithologen-Gesellschaft e.V. (DO-G) has provided us with funding for our fieldwork, for which we are very grateful. We now have enough funding for two months of fieldwork and analysis afterwards! A summary of the study will appear in the next issue of Vogelwarte, the German journal of DO-G.

See also here for a well-received recent report about the project on Birdguides. Feel free to comment!

Tuesday, 26 March 2013

Fieldwork is approaching

Spring has officialy started and our departure to Kazakhstan is coming ever closer! We had our final meeting last week in Wageningen and we will meet each other again in Korgalzhyn. Preparations are in full swing, accomodation is fixed, car is fixed (a traditional Lada Niva!), one Kazakh student will be joining us for the fieldwork, we heard from almost all grants we have applied for and almost all of the field equipment is inhouse. We are working on our visa, but that will work out fine. The field equipment (Ibuttons - small loggers for temperature measurements) need to be checked, installed and manipulated, exciting stuff!
On the 16th of April, Thijs will give a short presentation on the project in Wageningen and we even have planned our first 'real' talk about the project in October at the conference of DO-G in Regensburg.