The colonial nesting birds begin returning to Anaho Island in late February or early March. By April into May, the maximum number of American white pelicans, double crested cormorants, California gulls, and great blue herons have returned to Pyramid Lake. The mature breeding adults have formed their pair bonds, established nests and are incubating their eggs. The earliest arrivals are already tending to nestlings. The air around the island is busy with the comings and goings of birds as they travel back and forth form their feeding grounds.
As summer progresses, the chicks grow quickly, and the adult birds begin spending less time at the island, returning only enough to feed the chicks, but not staying to tend to them. By middle to late August, most of the chicks have learned to fly and leave the island with the adults for the foraging areas. Once the chicks leave the island, neither the chicks nor the adults return until the following year. As the air temperatures rises during late spring and early summer, the lizards and snakes that live on the island become more active.
By September, very few colonial nesting birds remain at Anaho Island. The reptiles remain active until the temperatures begin to cool.
Anaho Island is very quiet during the winter as most wildlife is in hibernation or wintering further south.