‘Ua‘u (Hawaiian Petrel)

Endemic, Endangered
Hawaiian Name: ‘Ua‘u
Scientific Name: Pterodroma sandwichensis
Family: Procellariidae

Population

World: possibly 20,000 individuals (based on at-sea surveys)
Maui: 450-600 breeding pairs

Feeding

• Highly pelagic

Diet: Squid, goatfish, lantern fish, crustaceans
Feeding techniques:

• Surface-seizing: grabbing fish while sitting on surface
• Contact-dipping: Flies low over water and catches fish while flying

Breeding

Known breeding colonies: Maui (Haleakalā Summit), Lāna‘i (Lāna‘ihale), Kaua‘i (Interior steep slopes in forests) and Hawai‘i Island (Mauna kea, Mauna loa & Kohala Mountains)

• Long-term pair bonds
• Bi-parental care
• Often return to natal colonies and or the same site year after year
• Lay 1 egg per breeding season

Incubation period: 56 days
Chick period: 100-115 days
Nest habitat: Excavate burrows in high elevation rock crevices or wet, dense forests

Life Cycle

Note: Lāna‘ihale breeding season happens 1 month later than Haleakalā breeding season, the dates below span both colonies
Mid-March-Late April: Adults arrive at colonies at night.

• Clean out nests/Dig new nests
• Re-establish pair bond via calling

May: Pre-laying exodus – adults leave colonies
June: Egg-laying
June – July: Incubation
Early August: Chick hatching

• Parents take turns feeding chick by regurgitation
• Feeding decreases with time

October-December: Chick fledging

‘Ua‘u Brochures

For even more detailed information about this seabird, download:

Hawaiian Petrel.pdf

MNSRP ‘Ua‘u Brochure (pictured below)