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.

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

2 comments:

  1. Well done guys for finding so many nests and putting out a lot of loggers. The variation in incubation strategies seems remarkable, some females seem to be off the nest a heck of a long time! The pattern above looks as if actually overheating of the clutch during mid-day was more of a problem for them than low temperatures. Will be very interesting to relate dung abundance and cover to these patterns later.
    Keep on the good work - Johannes

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