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Induced Ovulators

North American River Otters Mating and Giving Birth

North American River Otters are induced ovulators – copulation releases the female’s egg from the ovary.  Once the egg is released and fertilized, however, there is a nine to eleven month delay before the embryo begins actively developing (delayed implantation). Actual gestation takes about two months. Thus, otters sometimes give birth up to a year after mating, just before their next breeding cycle.  April and May are busy months for this semiaquatic mammal.

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