The following are the main threats to the remaining species: non-native diseases and predators (such as rats, barn owls, feral cats, and mongooses), invasive plants that change the environment, habitat degradation caused by humans and introduced ungulates, and Avian malaria and avian pox, which have devastating effects on forest bird populations that have evolved without these threats, are spread by non-native mosquitoes. Because of this, the majority of Hawaii’s remaining forest birds, or passerines, are confined to high elevation forests (above 1400 meters) or isolated islands where mosquitoes are either completely absent or have limited range due to temperature. Numerous logistical obstacles must be overcome in order to manage and study birds in these regions, including high costs, challenging field conditions, and the requirement for continuous management.
The forest birds of Hawaii are well-known throughout the world for their beauty, diversity, and (sadly) rarity. Of the 84 forest bird species that are known to exist, 28 are regarded as “prehistoric,” meaning that the only evidence for them comes from the fossil record and that they went extinct before the modern era of bird observation record keeping began. Thirty of the 56 species that were present in Hawaii during the time that people were there are either extinct or thought to be extinct. There are now only 26 species of forest birds remaining, and 24 of those have been classified as vulnerable, near-threatened, threatened, endangered, or critically endangered by the International Union for the Conservation of Nature. The ?apapane and the Hawai?i ?amakihi are the only two native forest bird species deemed to have healthy populations and to be at “least concern” for extinction risk.
At least 113 endemic species made up the extraordinarily unique and diverse avifauna of the Hawaiian archipelago before humans arrived. These species included flightless geese, ibis, rails, and the Hawaiian Honeycreepers (subfamily Drepanidinae), of which at least 59 species have been described. This is one of the most well-known examples of adaptive radiation. Hawaii bears the regrettable distinction of being among the epicenters of its species’ extinction. 48 birds were lost before European settlers arrived, and 23 birds have been confirmed lost since Captain Cook’s initial arrival in 1778. Of the 42 extant endemic taxa, 31 (29 species and 2 subspecies) are federally listed; however, the status of 10 of these have not been observed for up to 40 years.
Some of the audio used on this page was mixed from original tracks at xeno-canto.org, including XC216038 Akikiki Oreomystis bairdi- Patrick Blake; XC27320 Akekee Loxops caeruleirostris Dan Lane; XC144892 Puaiohi Myadestes palmeri- Eric Vanderwerf; XC27338 Anianiau Magumma parva- Dan Lane; XC27316 Kauai Amakihi Chlorodrepanis stejnegeri- Daniel Lane; XC27337 Kauai Elepaio Chasiempis sclateri- Daniel Lane; XC58937 Iiwi Drepanis coccinea- Frank Lambert; XC505432 Apapane Himatione sanguinea- Rich Sharloch; XC454888 Oahu Amakihi Chlorodrepanis flava- Sean Erroll MacDonald; XC410155 Oahu Elepaio Chasiempis ibidis- Dan Lane; XC122342 Akohekohe Palmeria dolei- Brooks Rownd; XC123887 Maui Parrotbill Pseudonestor xanthophrys- Brooks Rownd; XC58973 Maui Alauahio Paroreomyza montana- Frank Lambert; XC503722 Hawaii Amakihi Chlorodrepanis virens- Pheonix birder; XC124707 Hawaiian Hawk Buteo solitarius- Brooks Rownd; XC124794 Hawaii Akepa Loxops coccineus- Brooks Rownd; XC175246 Hawaii Elepaio Chasiempis sandwichensis bryani- Dan Lane; XC145608 Palila Loxioides bailleui- Eric Wanderwerf; XC747456 Akiapolaau Hemignathus wilsoni- Brooks Rownd; XC127667 Alawai Hawaii Creeper Loxops mana; XC27372 Short-eared Owl Asio flammeus- Dan Lane; XC58932 Omao Myadestes obscurus- Frank Lambert
The I’iwi, Kiwikiu, and Akikikiki are among the remaining birds that are threatened by a variety of factors, including the loss of their breeding and feeding grounds as well as direct predation by invasive species. Mosquito-borne diseases have further decimated populations of Hawaiian birds. Numerous of these birds are extremely vulnerable to diseases that are not native to the area, like avian malaria and pox, which are transmitted by imported mosquitoes.
This example of conservation success from the Northwestern Hawaiian archipelago is uncommonly as evident as it is. In 2011 and 2012, two small groups of critically endangered Millerbirds were successfully relocated from Nihoa to Laysan. With over 160 members, the Millerbird population on Laysan is growing and acting as a safety net against more natural disasters. (Photo: Megan Dalton) Read more.
Palila are now limited to a small area of m?mane forest high on Mauna Kea’s southwest slope; their former forest habitat was either overgrazed by sheep or converted to pasture. Along with our partners, we have planted over 90,000 trees on Mauna Kea in an effort to restore their habitat. Additionally, we are defending the forest from invasive species. (Photo: Michael Walther).
Effective fences help conserve birds throughout the Hawaiian islands by establishing sanctuaries where endangered species can reproduce in safety. Six acres of Kaua’i’s K?lauea Point National Wildlife Refuge are protected by a predator-proof fence funded by ABC, offering a secure environment for nascent seabird populations like Hawaiian Petrels (‘Ua’u) and Newell’s Shearwaters (‘A’o). (Photo: Jessica Behnke) Read more.