Seyed Mehdi Amininasab; Seyed Masoud Hosseini-Moosavi; Seyed Hossein Khazaei
Abstract
The current study stablished to determine reproductive characteristics of the Little Egret Egretta garzetta in Ali-Siyah Island in Karoon River during 2007-2008. The breeding phenology started in March 28 with nest making and ended with last fledglings in June 24, 2008. Thirty nests were selected randomly ...
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The current study stablished to determine reproductive characteristics of the Little Egret Egretta garzetta in Ali-Siyah Island in Karoon River during 2007-2008. The breeding phenology started in March 28 with nest making and ended with last fledglings in June 24, 2008. Thirty nests were selected randomly using boats. In total 100 eggs with mean of 3.33 (3-5) eggs per nest were found. The average breeding success in hatching, nestling and post-nestling stages were 62%, 65% and 75% respectively. The mortality rate in mentioned stages were measured 25%, 10% and 3% as well. The mortality rate showed significant difference before hatching stage in comparison with other breeding stages. Clutch size, brood size and nest parameters did not have significant effect on the breeding success. Natural factors had most negative effect on the breeding success regarding to the special geographical position and limited access to the Island.
Seyed Mehdi Amininasab; Seyed Masoud Hosseini-Moosavi; Seyed Hossein Khazaei
Abstract
Abstract
The current study carried out on the reproductive biology and breeding success of Crowned Night Heron Nyctiocorax nyctiocorax in Ali-Siyah island in Karoon River during 2007-2008. During the study, 30 nests were selected randomly using visits by boats. The reproductive phenology of Crowned ...
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Abstract
The current study carried out on the reproductive biology and breeding success of Crowned Night Heron Nyctiocorax nyctiocorax in Ali-Siyah island in Karoon River during 2007-2008. During the study, 30 nests were selected randomly using visits by boats. The reproductive phenology of Crowned Night Heron was started with the behaviour of nest building in March 22 and finished with last fledglings in June 19. From 91 eggs in 30 randomly selected nests, 3.03 eggs were found and the clutch size was varied from 2 to 5 eggs. The mean of breeding success in hatching, nestling and post-nestling breeding stages were 63.73% (n=58), 49.45% (n=45), 45.05% (n=41), respectively. The total breeding success during the breeding season was measured 52.74%. Clutch size, brood size and nest parameters did non-significant effects on the breeding success. Most mortality rate occurred before the hatching stage (36.26% (n=33)) mostly due to the natural factors.
