Breeding ecology and behaviour of the Great Reed Warbler, Acrocephalus arundinaceus, in Poyrazlar Lake, Turkey

In this study, the breeding ecology and behaviour of the Great Reed Warbler, Acrocephalus arundinaceus, was studied at Poyrazlar Lake, Turkey. The breeding period started in the first week of May. The incubation period lasted 14 days. As clutch size increased, the diameter of the nests became larger (r = 0.65). Diameters of nests containing different clutch sizes varied significantly from one another (P 0.01). However, their height did not change (r = 0.24). There was no significant height difference between nests containing different clutch sizes (P 0.05). As the nests became farther from the shore, the clutch size and the egg weight increased, because mature adults built their nests on the reeds in deeper areas (r = 0.59, r = 0.73). On the other hand, young breeders showed no location preference in their choice of nest site. The number of the nests showed a positive correlation with the height of reeds (r = 0.80). In all nests, 4 different behaviours (Nest Empty, Sitting, Edge of Nest Waiting, Feeding Nestlings) were observed from the appearance of the first egg until the female left the nest. On average, a given female spent 38.11% of her time away from the nest, 51.84% of her time in incubation, 0.91% of her time around the nest, and 9.24% feeding her nestlings per day.