Regional Ecosystems Research

Hawaiian forests are beset by many stressors, resulting in a complex pattern of altered ecosystems, impeirled species, and (in some areas) substantial protection and restoration. Short-term studies focused on specific sites or biota have limited value in understanding landscape-level change. Long-term and spatialy extensive data are needed to understand how ecosystems are reacting to both stressor...

The Keamuku Maneuver Area (KMA) is a 9,227 ha. unit of Army Pohakuloa Training Area (PTA) on Hawai‘i Island. The Army’s mission at KMA is threatened by erosional processes that could make parts of the training area too hazardous or too degraded for sustained use. These processes depend on vegetation dynamics and the nature of the soils underlying KMA. Knowledge of the training area was...

Restoration of ecological systems in wildland areas often involves restoring species to habitats degraded by invasive plant and animal species. Often, such invasive species exert community level impacts, such as direct competition, but may also alter ecosystem function. For example, invasive plants have been documented to alter fire regimes, soil nutrients and microbes, food webs, and/or...

The Laysan teal has the most restricted range of any duck species and is especially vulnerable to extinction because of its small population size and vulnerability to climate change. The species was believed to be endemic to one island until new sub-fossil evidence and ancient DNA-testing revealed Laysan teal were widespread across the Hawaiian archipelago. Despite its previously wide distribution...

USGS and Oregon State University (OSU) have joined forces to support USFWS with research needed help manage and recover the endangered Hawaiian duck, locally known as koloa maoli. Hybridization of koloa with feral Mallards on O‘ahu and Maui is believed to have resulted in complete introgression in those populations (Engilis et al. 2002), and Kaua‘i is the only island that likely supports a viable...

The federally endangered nēnē, or Hawaiian Goose, once present on most of the Hawaiian Islands, was found only on Hawai‘i Island by 1900. This remnant population was reduced to as few as 30 individuals by 1952 due to the combination of unregulated hunting, introduced mammalian predators, and large-scale habitat degradation. Nēnē have been restored to a few places like Hawai‘i Volcanoes National...

The palila is an endangered species of Hawaiian honeycreeper which exists only in subalpine forests dominated by māmane and naio on Mauna Kea Volcano. The diet of this finch-billed bird is unusually restricted; immature seeds, flowers, and insects found on māmane trees are critical to its existence. Māmane also is the preferred nesting substrate of the palila. Federal court orders have resulted in...

This project examined altitudinal movements of the endangered Hawaiian hoary bat and their use of high elevation caves on the slopes of Mauna Loa volcano on the island of Hawai‘i.

The Samoan swallowtail is a large and strikingly marked butterfly endemic to the Samoan Archipelago. Once widespread and common, its populations have declined dramatically, and it now appears restricted to the island of Tutuila, an area representing approximately 5% of its former range. There are few insects that are commonly thought of as indicators of ecosystem health, but the Samoan swallowtail...

‘I‘iwi populations have severely declined in recent decades in Hawai‘i Volcanoes National Park (HAVO) and elsewhere in the Hawaiian Islands due to the cumulative impacts of many invasive threats that have degraded habitats, disrupted food webs, competed for resources, depredated nests and birds, and transmitted diseases.

Conduct research needed to provide the information and knowledge necessary for decision-makers to make informed decisions pertaining to management of biological resources in Hawai‘i and the Pacific island ecosystems relative to changing climate conditions.

Hawai‘i has more endangered species than any other state - over 394 species. In spite of this fact, there is not a central clearing house for information on the status and trends of these species. Information is spread over the following areas: 1. USGS maintains some information on Forest Birds. 2. USFWS maintains summary data on listed and proposed plants. 3. The University of Hawai‘i maintains...