Midway Population

In 1984, about 6,000 nesting pairs were documented on Sand Island. Largest population in the Hawaiian Islands. Widely distributed in tropical Pacific and Atlantic Oceans.

Feeding Habits

Inshore surface feeders. Change diet with seasons. Feed on small fish brought to the surface by predatory fish such as tuna and jacks.

Breeding

Courtship consists of head nodding and fish transfers. Extensive nests are built in trees with grasses, leaves, and twigs. Old nests are sometimes renovated and reused. On Midway, noddies have adapted to nesting in tall ironwood trees (Casuarina equisetfolia). In the absence of ironwood trees, noddies nest in naupaka (Scaevola sericea) and beach heliotrope (Tournefortia argentea) shrubs in the Northwestern Hawaiian Islands. One speckled egg is laid. Incubation lasts approximately 36 days. Incubation shifts average about one half day.

Chicks are brooded for several days after hatching with feedings approximately once every 11 hours. After about three weeks adults spend little time with chicks, except for feeding. Chicks are fed regurgitated fish or whole fish as they get older.

Fledging occurs approximately 36 days after hatching. Post-fledging feeding continues for several weeks.

Nesting occurs throughout the year on Midway, with peak activity in January, February and July and August.