Notes on status and ecology of the endangered Hawaiian annual 'Āwiwi, Centaurium sebaeoides (Gentianaceae)

Pacific Science
By: , and 

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Abstract

The annual, endemic, coastal herb Centaurium sebaeoides is the only native Hawaiian species in the gentian family. The U.S. Fish and Wildlife Service listed it as Endangered under the Endangered Species Act on 29 October 1991. Before surveys reported here, the total population of this species statewide was estimated at 80-110 individuals in eight populations. During counts made in April and May 1997, following ample winter rains, 12 populations of C. sebaeoides with a total of 6300-6600 plants were noted on five islands (Kaua'i, O'ahu, Lana'i, Moloka'i, and Maui). Five populations were mapped with a global positioning system and counted; in the remaining seven populations, the numbers of individuals were estimated. More recent surveys in 1998-1999 estimated a total of only 60-80 individuals at all sites. Such dramatic population fluctuations are believed to be related to the sporadic occurrence of winter rains. Threats that further contribute to the rarity of the species include (1) displacement and overtopping by salt-tolerant nonnative woody species, especially Casuarina spp., (2) trampling and erosion of habitat by ungulates, and (3) damage caused by off-road vehicles.

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Publication type Article
Publication Subtype Journal Article
Title Notes on status and ecology of the endangered Hawaiian annual Awiwi, Centaurium sebaeoides (Gentianaceae)
Series title Pacific Science
Volume 54
Issue 4
Year Published 2000
Language English
Publisher Pacific Science Association
Publisher location Honolulu, HI
Contributing office(s) Pacific Island Ecosystems Research Center
Description 6 p.
First page 517
Last page 522
Country United States
State Hawaii
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