Island Birds Depend on Essential—But Sometimes Rare—Public Lands
• Among declining Hawaiian forest birds on Kaua‘i, such as Puaiohi and ‘Anianiau, an average of 78% of their distribution is on state land. Four endangered species in the Northwest Hawaiian Islands occur entirely on federal lands.
• Eighty-five percent of state land in
Hawai‘i is open to uses incompatible with bird conservation, undermining efforts to manage, protect, and restore critically important habitat for endangered birds.
• Continued conservation efforts are
needed by DoD in cooperation with
USFWS and NOAA’s National Marine Fisheries Service in Guam and the Commonwealth of the Northern Mariana Islands, especially in light of planned expansion of military bases.
• In Puerto Rico, the endangered Puerto Rican Parrot and Elfin-woods Warbler are highly dependent on the small amount of public land. The future of birds on public lands depends on cooperative projects with adjacent
private landowners and the expansion of public protected areas.
|Image: Hanawi Natural Area Reserve, Hawai'i, by Ashey Dayer|
Birds on Public Lands in Hawai‘i
One-third of all birds listed under the Endangered Species Act (ESA) are native to Hawai‘i. Ten of these may already be extinct. Public lands in Hawai‘i are vitally important, with more than 50% of land area under state or federal management. Averaged across Hawai‘i, public land supports about 73% of the distribution of upland/forest birds. State lands support 45% of the average proportion of species’ ranges, mostly managed by the Department of Lands and Natural Resources. State lands are particularly important for declining forest birds on Kaua‘i, with 78% of the distributions of species such as Puaiohi and ‘Anianiau.
In the Northwest Hawaiian Islands, 100% of all endangered Laysan Ducks, Laysan and Nihoa finches, and Millerbirds are under federal management. Nearly 50% of high priority wetlands for endangered waterbirds is federally managed in National Wildlife Refuges (NWRs). Recent restoration at Hanalei and Huleia NWRs on Kauai is having a dramatic, positive impact on populations of endangered Hawaiian Duck (Koloa), Hawaiian Coot (‘Alae ke‘oke‘o), the Hawaiian subspecies of Black-necked Stilt (Ae‘o) and Common Moorhen (‘Alae ‘ula), and Nēnē (Hawaiian Goose).
Invasive nonnative species are pervasive problems. Intensive
management is necessary, especially fencing and removing grazing
mammals such as pigs, goats, and mouflon/sheep, and controlling
predators such as cats, rats, and mongooses. Haleakala and Hawai‘i
Volcanoes national parks have been fenced and nonnative grazing mammals
almost completely excluded, benefiting forest recovery.
The U.S. Army conducts predator control on 250 acres of O‘ahu ‘Elepaio habitat and the state conducts predator control in Palila habitat in Mauna Kea Forest Reserve. However, 85% of state land is open to uses known to be incompatible with bird conservation. The needs of protecting birds listed under the ESA often come second to management for hunting. Proposals to fence land for ungulate removal often cause agency-public conflict over reduced hunting opportunities. Better outreach is needed to build public understanding and support for fencing lands important to endangered birds and for eradicating nonnative grazing mammals in fenced areas.
|Rufous Fantail by Jack Jeffrey|
Invasive, nonnative species and military expansion are two of the greatest threats to the nine endangered bird species and six other species of conservation concern. Nearly 50% of land in Guam and 80% in CNMI is under public management. The average percentage of bird species’ distributions on territorial and federal lands is 58% on Guam and 18% on CNMI. Public land is very important on Rota, CNMI, where 81% of the range of an experimental Guam Rail population and 69% of the distribution of the endangered Mariana Crow are on territorial land. On Guam, the rail has been extirpated and only two male crows remain, so Rota populations are essential for the species' survival. DoD is the leading federal land manager in Guam and CNMI, managing 20% of the land area, including about two-thirds of Tinian, CNMI, where the Tinian Monarch, delisted in 2004, may face new threats from military expansion. The nonnative brown tree snake has extirpated all native forest birds on Guam, and is a major threat to remaining species if it spreads to CNMI. The DoD-funded Micronesia Biosecurity Plan is important to identify threats from brown tree snakes and other invasive species and to prevent their accidental exportation to other islands. It will require concerted efforts from DoD and partner agencies and organizations to implement appropriate prevention, early detection, and rapid responses. DoD is also trapping brown tree snakes at cave sites of the endangered Guam Swiftlet.
In American Samoa, 73% of the land is territorial and the NPS is the most significant federal land manager, with 27% under lease as the National Park of American Samoa. The NPS controls invasive species and monitors bird populations there. An average of 86% of bird distributions is on territorial land. The Fiji Shrikebill and the Blue-crowned Lorikeet have more than 27% of their distribution in Guam, CNMI, and American Samoa, an ongoing challenge is increasing the amount of land managed for birds in cultures that generally have a utilitarian view of wildlife. In light of planned military base expansion in Guam and CNMI, continued collaboration and cooperation by DoD with USFWS and the National Marine Fisheries Service is needed to enhance conservation.
|Puerto Rican Parrot by Tom MacKenzie,
With 16 endemic species and six listed under the ESA, these islands give the U.S. a significant stake in the conservation of West Indian biodiversity. Only 8% of the Commonwealth of Puerto Rico and 11% in the U.S Virgin Islands (USVI) are under public management. Seventeen percent of the distribution of forest birds such as the endangered Puerto Rican Sharp-shinned Hawk and endemic Puerto Rican Tody is protected on commonwealth or federal land. The El Yunque National Forest and commonwealth forests include 97% of the ranges of the Puerto Rican Parrot and 51% of the Elfin-woods Warbler. The average distribution of 25 other forest species on public land is just 9%. Among waterbirds such as West Indian Whistling-Duck and White-cheeked Pintail, the percentage is much higher, with 44% in coastal commonwealth refuges and NWRs offering significant protection.
In Puerto Rico, the commonwealth manages 58% of public land. The USFS is the largest federal landholder, managing 28,242 acres in the El Yunque National Forest (16% of lands in Puerto Rico managed by state and federal agencies). The NPS manages 72% of public land in the USVI as Virgin Islands National Park, important for many bird species. In Puerto Rico and the USVI, the vast majority of land is private and open to development. Wind farm and cell tower construction clear forests important for species such as Puerto Rican Nightjar and Elfin-woods Warbler. Species with ranges largely on private land are especially vulnerable, such as the endangered Plain Pigeon. Their future depends on cooperative projects with private landowners and increases in public protected areas.
• Hanawi Natural Area Reserve and Hakalau Forest National Wildlife Refuge are two of the very few sites in Hawai‘i where native forest birds are stable or increasing. Endangered species such as Maui Parrotbill (Kiwikiu), Crested Honeycreeper (Ākohekohe), Ākepa, and Hawai‘i Creeper benefit from intensive ungulate control and reforestation.
• On Saipan, CNMI, an upland mitigation bank was established on territorial land to offset impacts of development on the endangered Nightingale Reed-Warbler.
• In Puerto Rico, the persistence of the Puerto Rican Parrot is due almost entirely to provision of nest boxes, control of predators and competitors, and captive breeding and reintroduction in El Yunque National Forest and adjacent forests.
• Shiny Cowbirds in Puerto Rico often lay their eggs in the nests of endangered Yellow-shouldered Blackbirds. Intensive control of cowbirds on Cabo Rojo and Laguna Cartagena NWRs is improving reproductive success of the blackbirds and other species.