Hawaii

Jen Rothe and Alex Wang, Regional Report Compilers

The Hawaii region includes the entirety of the Hawaiian Archipelago, a remote chain of 137 volcanic islands stretching 1500 miles across the central North Pacific. The archipelago itself is mostly part of the U.S. State of Hawaii, but it also includes Midway Atoll, which is an unincorporated territory of the U.S. For ornithological purposes, the Hawaii region is often divided into two subregions: the Main Hawaiian Islands and the Northwestern Hawaiian Islands.

The Northwestern Hawaiian Islands are a scattered collection of ancient, eroded pinnacles and atolls, many of which barely protrude above sea level. Remote and rarely visited (only Midway and Kure Atolls see year-round human habitation), the entire subregion provides vital nesting habitat for 14 million seabirds of 22 species and is also home to three endemic passerines and Laysan Duck. The islands themselves, as well as surrounding waters, are protected within Papahānaumokuākea Marine National Monument, one of the largest marine reserves in the world.

The eight main Hawaiian Islands lie at the southeastern end of the archipelago. They include Hawaiʻi (also known as “the Big Island”), Maui, Kahoʻolawe, Lānaʻi, Molokaʻi, Oʻahu, Kauaʻi, and Niʻihau. Most of these islands are well-populated, with often-dense vegetation that strongly correlates with the diverse climate subtypes present in the islands. Prevailing northeast trade winds result in windward-facing slopes being some of the wettest places in the world, whereas leeward “Kona” coasts are typically more arid. Geologically, the main islands are the youngest and least eroded: most rise thousands of feet above the ocean. Mauna Kea, on the Big Island, towers nearly 13,800 feet above sea level and occasionally sees snow deposited at its summit.

This astounding diversity of habitats gave rise to an array of avifauna as unique as Hawaii’s biogeography. The famed branch of cardueline finches known as the Hawaiian honeycreepers—including the cross-billed ‘Akepa and iconic scarlet ‘I’iwi—is one of the planet’s most dramatic examples of adaptive radiation. However, with high rates of single-island endemism comes extreme vulnerability to introduced threats, such as predators and mosquito-borne disease. Indeed, Hawai’i accounts for fully one third of all birds protected by the U.S. Endangered Species Act. Often called “the extinction capital of the world,” the islands have a grim history and have already lost some 70 bird species and an entire endemic bird family (Mohoidae). Today, 34 Hawaiian endemics still brighten the landscape. These include the charismatic Nēnē (Hawaiian Goose), several native waterbirds, the ‘Elepaios (monarch flycatchers), heterobill “honeycreepers”, and the montane-breeding ‘Ua’u (Hawaiian Petrel) and ‘A’o (Newell’s Shearwater).

The ABA gratefully acknowledges the contributions of Hawaii Regional Report Compilers Jen Rothe and Alex Wang to promoting knowledge and understanding about the birdlife of the continent.