Tan Gim Cheong came across an active nest of the Zitting Cisticola (Cisticola juncidis) on 3rd May 2009 that ended in the fledging of three chicks on the 17th. The nest was built within a clump of sedges (Fimbristylis schoenoides), some of whose stems were up to 60 cm high. The slender vertical nest was about 15 cm from the ground (above left). The opening of the nest was at the top and the egg chamber is neatly lined with whitish plant floss held together by spider silk (above right).
He encountered another nesting, this time with a brood of four on 11th May. On 26th May he further came across yet another active nesting, again with four chicks. He collected all three nests after the chicks fledged and deposited them with the Raffles Museum of Biodiversity Research, National University of Singapore.
One disused nest was made available for study, the details of which are presented below. The image below (left) shows the outline of the oval basal portion of the nest surrounded by stems of the sedges. Note that the nest proper is constructed with grass or sedge leaves, with numerous strands of spider silk used to attach it to the stems (below middle). In the image below (right), the nest has been pulled apart somewhat to show the inner lining of plant down and spider silk. Note the brown-orange masses, probably also of plant origin.
A total of 279 sedge stems were used to support the nest, most passing through the periphery. Of these about 47% were attached to the nest with the aid of spider silk. The fragments of silk were either wound round the stem or passed through an opening made on the surface (below).
The actual nest, 10 cm high and 5 cm wide at the base, narrows somewhat to a width of 3 cm at the top opening. The inner layer is a neat lining of white down weaved together into an elastic layer with the aid of spider silk.
Images of nest in the field and view of the egg chamber by Tan Gim Cheong (top two). Others by YC.
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