Managing conservation reliant species: Hawai'i's endangered endemic waterbirds

• Published in: PloS one 2013-06, Vol.8 (6), p.e67872-e67872
• Main Authors: Underwood, Jared G, Silbernagle, Mike, Nishimoto, Mike, Uyehara, Kim
• Format: Article
• Language: English
• Subjects: Anas wyvilliana; Animal behavior; Animals; Aquatic birds; Biology; Birds; Branta sandvicensis; Coastal plains; Coastal waters; Conservation; Conservation of Natural Resources - statistics & numerical data; Earth Sciences; Endangered & extinct species; Endangered species; Endangered Species - statistics & numerical data; Female; Fulica alai; Gallinula galeata sandvicensis; Hawaii; Himantopus mexicanus; Himantopus mexicanus knudseni; Male; Nature reserves; Plains; Population viability; Protection and preservation; Refuges; Seasons; Waterfowl; Wetland management; Wetlands; Wildlife; Wildlife conservation; Wildlife management; Wildlife refuges
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0067872

Hawai'I's coastal plain wetlands are inhabited by five endangered endemic waterbird species. These include the Hawaiian Coot ('alae ke'oke'o), Hawaiian Duck (koloa maoli), Hawaiian Stilt (ae'o), Hawaiian Gallinule (Moorhen) ('alae 'ula), and Hawaiian Goose (nēnē). All five species are categorized as being "conservation reliant." The current strategy to recover these endangered birds includes land protection and active management of wetlands. To assess the effectiveness of the current management paradigm, we compared species population trends across the state to those on six actively managed wetland national wildlife refuges (Refuges) thought to be critical for the survival of these endangered species. To perform the evaluation we relied on systematic semiannual population counts that have been conducted across most wetlands in the state and monthly population counts that have occurred on Refuges during the same time period. We found that statewide and Refuge populations of the Hawaiian Coot, Stilt and Gallinule have rebounded from historic lows and over the last 20 years have slowly increased or remained stable. We also documented that Refuges are important to each species year-round and that a disproportionately larger percentage of the population for each species is found on them. Understanding of why Refuges successfully house a disproportionate percentage of these "conservation reliant" species can inform current and future conservation efforts as well as ensure long-term population viability for these species.