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Name: Jim
Status: other
Age: other
Location: LA
Country: N/A
Date: 3/30/2005

My question relates to the Eastern Screech Owl. How are their eggs fertilized? Does his sperm have to penetrate an egg shell or is the shell formed after mating/fertilization? If the shell is formed after, how long does it take to form and how long after mating will the egg be laid? Must the pair mate once for every egg laid or may the usual clutch of three eggs be fertilized after one mating?

In general reproduction in birds follows this pattern: during copulation semen and sperm are put in the female's cloaca, from which sperm swim up the oviduct and fertilize the eggs. Shells form as the eggs develop, and fully formed eggs may be laid by the female within a few days. A clutch of eggs may come from a single or more than one mating. I don't have specific information on screech owls but they follow the basic pattern.

J. Elliott

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