Observation on Nest Building Activity of Siberian Crane

By Maria Vladimirtseva and Sergei Sleptsov

In the course of our research of breeding biology of the Siberian Crane at Kytalyk Resource Reserve (north-east part of Yakutia) in 2004, we managed to monitor the process of nest building by a pair of cranes at a site nearby Djyukarskoye Lake. This pair has been observed since 1991, when their chick was banded.

In the second decade of June 2004, the pair began building a new nest 300 m away from the old one, which still was under the snow. The new nesting site was free from snow, and to all appearances, the construction of the nest base was finished, because one bird sat on the nest while another continued collecting and bringing building material. The collection process seemed interesting. The crane was moving away from the nest, gathering the tufts of grasses, consistently pulling it out and throwing backwards, on each side of its path, thereby creating a trail of “mowed” grass approximately 10 m long. Then the crane began throwing bunches of pulled grass towards the nest, repeating this route several times until all the building material was gathered near the nest, so that it could be used for construction without any further walks back and forth. All this time the second bird sat in the nest (which suggests the presence of hatching eggs) gathering and arranging the vegetation brought by the partner and tucking it under its body.

For several minutes the cranes switched places, and the bird that previously sat in the nest was now bringing the ”mowed” vegetation to the nest.

During the next shift the first crane, more active in the nest-building process, made another “mowed” grass path on the opposite side of the nest.

While throwing the grass backwards the cranes didn’t change the position of the body, just bended the neck and the head backwards at each throw.

Therefore, collecting the nest-building material, the Siberian Cranes used two interconnected techniques: vegetation “mowing” and throwing the “mowed” vegetation towards the nest.

One more recently built nest has been discovered to the east of the Banyl Lake, in an unusual for the Siberian Crane habitat – 70 m away from the “bulgunnyakh” – a knoll of the ground heave. Traces of the vegetation pulled out close to the nest were evenly arranged so that the nest was sitting in the middle of the “mowed” area.

According to our observations, Siberian Cranes in Yakutia sometimes build temporary nests within their nesting territory, if the weather conditions prevent them from using old, permanent nest.

It is possible that the discovered nests belong to such type of constructions.

For more information:

Maria Vladimirtseva and Sergai Sleptsov

Institute of Biological Problems on Cryolitozone, Yakutia