In terms of MPAs showing effectiveness in protecting marine mammal populations, the Banks Peninsula Marine Mammal Sanctuary was established in 1988 along the east coast of New Zealand’s South Island to reduce the number of endemic, endangered New Zealand Hector’s dolphins (Cephalorhynchus hectori) dying in nets. The area protected was 1170 km2 . Drawing on 21years of photo-identification surveys, researchers Andrew M. Gormley and colleagues determined that the mean annual survival rate had improved and that the population had shown a 6% increase in mean annual population growth.