The high levels of sex segregation and fragmentation of different populations in Hector's dolphin have been discussed as contributing to the overall population decline, as it becomes more difficult for males to find a female and copulate. The Allee effect begins to occur when a low-density population has low reproductive rates leading to increased population decline. In addition, low gene flow between populations may result from this species' high foraging site fidelity. Hector's dolphins have not been found to participate in alongshore migrations, which may also contribute to their lack of genetic diversity.