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SAMUEL M. GON, III 
The Nature Conservancy of Hawai‘i

ALLEN ALLISON
Bernice Pauahi Bishop Museum

RONALD J. CANNARELLA
Hawai‘ i State Department of Land and Natural Resources

JAMES D. JACOBI
U. S. Geological Survey, Biological Resources Division

Because of Hawaii’s unique geography as a tropical island archi-
pelago, the national GAP methodology will be augmented in a few
key areas. First, our analysis of biodiversity will expand the focus
beyond vertebrate indicators to include representative plant and in-
vertebrate taxa. We recognize that the spatial resolution for land
cover mapping in Hawai‘i will have to be at a higher resolution
than on the mainland in order to capture significant areas of
biodiversity, which on a per unit area basis is higher in Hawai‘i
than in any other place in the US. We will also expand the concept
of land stewardship to include protection from emerging threats,
particularly the impact of invasive non-native species. Finally, we
will incorporate and integrate Aquatic GAP into our primary ef-
forts.

Hawaiian Biodiversity and Its Loss
Approximately 90% of Hawaii’s 1,000 native species of flowering
plants are found nowhere else on earth (Wagner et al. 1999). It is
estimated that Hawai‘i has over 10,000 species of endemic insects
(Eldredge and Miller 1995). All 80 species of land birds once found
in Hawai‘i are endemic to these islands (Jacobi and Atkinson 1995).
Given the extraordinary level of endemism, Hawai‘i is regarded as
a globally significant “hot spot” of biodiversity.

However, with the arrival of the Polynesian explorers approximately
2,000 years ago and, more recently, with the “discovery” of Hawai‘i
by Westerners in 1778, major impacts have been brought to Hawai-
ian ecosystems and their unique biota. Today, Hawai‘i is home to
approximately 33% of the nation’s total endangered species
(USFWS 1998), and nearly 75% of the recorded extinctions in the
United States have involved endemic Hawaiian species. This pro-
cess continues and may be accelerating. Federal, state, and private
conservation organizations currently working in Hawai‘i agree that
nearly all of Hawaiian native biota should be regarded as threatened.

The loss of biodiversity is directly linked to landscape alteration
(e.g., agriculture, urbanization, resort development, and recreation)
and the growing number of non-native, injurious species. Weeds in
particular are widely regarded as posing the greatest threat to
biodiversity and native ecosystems in Hawai‘i. Nearly half the to-
tal land area of the archipelago is now occupied by altered land-
scapes or alien-dominated ecosystems that have displaced native
species (Pratt and Gon 1998). Alien species now comprise nearly
20% of the overall biota in Hawai‘i (Eldredge and Miller 1995).

Hawai‘i GAP
The national GAP program grew out of the Hawai‘i Forest Bird
Survey, which was an innovative project initiated in the 1970s to
evaluate the distribution, status, and threats to habitats of endan-
gered Hawaiian forest bird populations (Scott et al. 1986, Scott et
al. 1987). Since then, research and management efforts in Hawai‘i
have expanded to include taxa other than birds. In 1995, the Ecodata
Group (EDG) was established by several federal, state, and private
organizations to facilitate the sharing of environmental data and to
coordinate data collection efforts statewide. EDG was instrumen-
tal in developing the Hawai‘i GAP project to take advantage of its
well-tested methodologies and rigorous data quality standards.

Hawai‘i GAP will follow closely the standard methodology, with a
couple of noteworthy innovations. Most significantly, because much
of Hawaii’s extraordinary biodiversity is expressed in its flora, we
will be looking at the distribution of key plant and invertebrate taxa
in addition to the distribution of vertebrates when developing our
species distribution maps. Second, we will be mapping the biologi-
cal elements in our freshwater streams. Finally, we will be map-
ping key threats to biodiversity, including the distribution of feral
ungulates, avian disease, weeds, and fire. While we recognize the
importance of the marine aspects of biodiversity in Hawai‘i, our
initial GAP effort will not include a marine component. In the course
of the terrestrial/aquatic GAP project, we will consider the feasibil-
ity of developing coral reef and nearshore marine coverage and other
important biodiversity elements.

Conclusions
Studies in Hawaiian avifauna during the 1970s contributed to the
development of the current GAP framework. It is our hope that we
can continue to further the process of refining the GAP methodol-
ogy by including nonvertebrate taxa and environmental threats when
evaluating the implications for conservation of Hawaii’s biodiversity.

Literature Cited
Eldredge, L., and S. Miller. 1995. How many species are there in
Hawai‘i? B.P. Bishop Museum Occasional Papers 41:3-18.

Jacobi, J.D., and C.T. Atkinson. 1995. Hawaii’s endemic birds.
Pages 376-381 in E.T. LaRoe et al., editors, Our Living Re-
sources. U.S. Department of the Interior, National Biological
Service, Washington, D.C. 530 pp.

Pratt, L., and S.M. Gon III. 1998. Terrestrial ecosystems. In: S.P.
Juvik and J.O. Juvik, editors, Atlas of Hawai‘i. University of
Hawai‘i Press.

Scott, J.M., B. Csuti, J.D. Jacobi, and J.E. Estes. 1987. Species
richness: a guide to protecting future biological diversity. Bio-
science 37(11): 782-788.

Scott, J.M., S. Mountainspring, F.L. Ramsey, and C.B. Kepler.
1986. Forest bird communities of the Hawaiian Islands: Their
dynamics, ecology, and conservation. Studies in Avian Biology
9. 431 pp.

U.S. Fish and Wildlife Service. 1998. Endangered and threatened
wildlife and plants. 50 CFR 17.11 and 17.12.

Wagner, W.L., D.R. Herbst. and S.H. Sohmer. 1999. Manual of
the flowering plants of Hawai‘i. B. P. Bishop Museum Spec. Pub.
97. University of Hawai‘i Press and Bishop Museum Press.