Breeding success and daily survival rate of the Great Cormorant (Phalacrocorax carbo sinensis) in Amirkelayeh International Wetland, Iran

Great cormorant is dependent on aquatic ecosystems. The breeding success and daily survival rate of the Great Cormorant Phalacrocorax carbo sienensis (early April until late of July) was studied in 2009 in a colony at Amirkelayeh international wetland, south of the Caspian Sea, Iran.
In this study, Mayfield method was use to estimated nest survival during incubation and nestling and post- nestling stages.
Findings: The mean of clutch size was 2.88±0.8 eggs in each nest Based on this method, daily survival rate nests in incubation period was 98.3%,in nestling and post-nestling were 99.4%and 100% respectively. The overall breeding success was 56.4%.
Discussion and Results of this study showed there were higher stages of chick rearing than the incubation period and no losses occurred in fledged chicks. Some climatic factors such as high wind and prolonged rain had more impacts and losses in incubation period (30.7%).In other hand, chicks are more sensitive in nestling stage. Results suggest that Amirkelayeh colony site needs more improvement mitigation for better conservation of the cormorant colony in breeding period.