NIDIFICATION ET PONTE DE GANGA UNIBANDE Pterocles orientalis (LINNEAUS, 1758) DANS LA RÉGION DE BISKRA, ALGÉRIE

Abstract

ABSTRACT This study focuses on the Breeding biology of the Black-bellied Sandgrouse which located in the Ziban steppes. It aims to describe the clutch size during two successive breeding seasons, and the main characteristics of nests occupied by the parents during this period. Also the biometric measurement obtained on the samples encountered in the field. Over two years (2013-2014) a sample of N = 33 nests, the mean diameter nests is 156.90 (mm) ± 3.56 and the average depth is 24.30 (mm) ± 1.62. The average clutch size is 2.96 ± 0.17. Biometric measurements covered a sample of N = 98 eggs. The average length is 47.97 (mm) ± 1.25 and the average width is 32.47 (mm) ± 1.13, with an average weight of 24.78 (g) ± 1.74. The average volume is 25.86 (cm3) ± 2.24, the average density equal to 0.96 (g / cm3) ± 0.068, the average aspect ratio is 67.69 ± 2.12 and the average shell index is 0.51 ± 0.03. The spearman correlation test results showed that the density "D" is negatively correlated with the volume and the shape index , however there is a positive correlation between those two variables and the rest of parameters.