The expedition began with the goal of exterminating domestic rabbits that had been introduced to Laysan island by the guano industry in 1902. Since that time, the rabbits had devoured Laysan's vegetation and led to the extinction of several endemic species. The rabbits were eventually eliminated on Laysan, and the crew witnessed the extinction of the Laysan honeycreeper (ʻapapane). Throughout the expedition, new species were discovered and named, and unique specimens were captured and returned to laboratories for further study. Over 100 archaeological sites were found, including ancient religious sites and prehistoric settlements on Nihoa and Necker Island.
The first expedition departed Honolulu on April 4, 1923, and returned on May 4.[2] The team visited the island of Laysan, Pearl and Hermes Atoll, Midway Atoll, and Kure Atoll. When they spent a month on Laysan studying the endemic Laysan honeycreeper, a violent and sudden storm ravaged the island. After the storm, the crew concluded that the last three specimens of the honeycreeper had been killed.
The third expedition departed Honolulu on June 9.[2] The team visited the islands of Necker, Nihoa, and the French Frigate Shoals. An attempt was also made to visit Kaula. Tanager arrived at Nihoa on June 10 and dropped off scientists for a ten-day visit and moved on to Necker the following day to drop off a second team. Both teams used radio to keep in constant communication between the two islands.[3] On Nihoa, botanist Edward Leonard Caum collected the first specimen of Amaranthus brownii and Alexander Wetmore discovered the Nihoa millerbird and named it Acrocephalus familiaris kingi, in honor of Captain Samuel Wilder King.[4] Evidence of an ancient settlement on Nihoa was discovered, along with platforms, terraces, and human remains.[5]
On June 22, the Tanager arrived in the French Frigate Shoals and remained for six days, completing the first comprehensive survey of the atoll.[6] The expedition returned to Honolulu on July 1.[2]
The fourth expedition consisted of two teams, with the first departing Honolulu on July 7.[2] Destinations included Johnston Atoll and Wake Island. The first team left on the Whippoorwill (AM-35), which made the first survey of Johnston Island in the 20th century. Aerial survey and mapping flights over Johnston were conducted with a Douglas DT-2 floatplane carried on her fantail, which was hoisted into the water for take off. Two destroyer convoys accompanied the expedition from Honolulu. The Tanager (AM-5) left Honolulu on July 16 and joined up with the Whippoorwill to complete the survey. From July 27 to August 5, the expedition surveyed Wake Island and named its islets: The southwest islet was named after Charles Wilkes who had led the United States Exploring Expedition in 1841 and determined the location of Wake Island. The northwest islet was named after Titian Peale, the chief naturalist for the 1841 expedition.
The fifth expedition visited Nihoa and Necker Island in 1924.[7] Archaeologist Kenneth P. Emory of the Bishop Museum cleared out 60 sites on Nihoa and collected and cataloged artifacts.[5] The expedition visited Necker from July 14–17.
In 1990, the U.S. congress passed the Native American Graves Protection and Repatriation Act which requires federal agencies and institutions that receive federal funding to return Native American cultural items and human remains to their people. In the 1990s, Hui Mālama (Hui Mālama I Na Kūpuna O Hawaiʻi Nei), a Native Hawaiian group, spent two years petitioning the United States Fish and Wildlife Service for the release of the bones (iwi) from seven Hawaiian skeletons originally taken from Nihoa and Necker Island by the Tanager Expedition in 1924. Although the bones were owned by the USFWS, the Bishop Museum acted as custodian.[8] The bones were finally released to the group, and in November, 1997, Hui Mālama chartered a yacht and travelled to Nihoa and Necker to rebury the remains.[9]
Christophersen, Erling; Caum, Edward L. (1931-07-01). Vascular plants of the Leeward Islands, Hawaii. Bernice P. Bishop Museum Bulletin No. 81; Tanager Expedition Publication No. 7. Honolulu, Hawaiʻi: Bishop Museum Press.
Emory, Kenneth P. (2002) [1928]. Archaeology of Nihoa & Necker Islands. Mutual Publishing. ISBN1-56647-565-1.
Evenhuis, Neal L.; Eldredge, Lucius G., eds. (2004). Natural History of Nihoa and Necker Islands. Bishop Museum Bulletin in Cultural and Environmental Studies; No. 1. Honolulu, Hawaii: Bishop Museum Press. ISBN1-58178-029-X.
Gregory, H. E. (1924). "Report of the Director for 1923". Bernice P. Bishop Museum Bulletin (10).
Gregory, H. E. (1925). "Report of the Director for 1924". Bernice P. Bishop Museum Bulletin (21).
Kirch, Patrick Vinton (1985). Feathered Gods and Fishhooks: An Introduction to Hawaiian Archaeology and Prehistory. University of Hawaii Press. ISBN0-8248-0981-5.
Rauzon, Mark (2001). Isles of Refuge: Wildlife and History of the Northwestern Hawaiian Islands. University of Hawaii Press. Honolulu, Hawaii: Bishop Museum Press. ISBN0-8248-2330-3.
Ayau; T. K. Tengan (2002). "Ka Huakaʻi o Na Oʻiwi - The Journey Home". In Cressida Fforde; Jane Hubert; Paul Turnbull (eds.). The Dead and Their Possessions: Repatriation in Principle, Policy, and Practice. Routledge. pp. 171–189. ISBN0-415-34449-2.
Palmer, H. S. (1927). "Geology of Kaula, Nihoa, Necker and Gardner Islands, and French Frigate Shoals". Bernice P. Bishop Museum Bulletin. Tanager Expedition Publication Number 4. 35.
Wetmore, Alexander (July 1925). "Bird Life among Lava Rock and Coral Sand; Photographs Taken on a Scientific Expedition to Little-known Islands of Hawaii". National Geographic. 48 (1). National Geographic Society: 76–108.