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 M√ľnster 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.

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. 

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