Breeding biology of the Black-bellied Sandgrouse Pterocles orientalis in west-central Morocco

Aspects of the breeding biology of the Black-bellied Sandgrouse Pterocles orientalis were investigated in an arid area of west-central Morocco in the 2003 and 2004 seasons. Back-dating clutches and broods indicated that successful nesting lasted 13–18 weeks from mid-April to late August. The clutch frequency distribution showed two successive high and less important peaks in May and July, respectively. Among 50 nests 10.5%, 36.8% and 52.7% in 2003 and 9.7%, 25.8% and 64.5% in 2004 were found with one, two and three eggs per clutch, respectively. The mean clutch size was 2.55 eggs ± 0.50 (SD). The eggs' mean weight was 25.14 g ± 1.77 and measured 47.31mm ± 1.67 in length and 31.42mm ± 1 in width. The mean egg volume was 23.86 cm³ ± 1.83. The incubation period was about 26 d and the average hatchability rate was 62.5%. The differences in the breeding biology patterns between the population of west-central Morocco and those from other localities could be attributed to the geographic variation in environmental conditions. The data obtained are helpful for the conservation and reinforcement of declining populations of the Black-bellied Sandgrouse in west-central Morocco.