U.S. Fish & Wildlife Service Draft Revised Recovery Plan for Hawaiian Waterbirds Second Draft of Second Revision Clockwise from upper left: Hawaiian clacks, Hawaiian stilt, Hawaiian common moorhen, and Hawaiian coot. ©Erie A. VanderWerf. Used with permission. AR00045351 Draft Revised Recovery Plan for Hawaiian Waterbirds, Second Draft of Second Revision (May 2005) (Original approved 1978; First Revision approved 1985; First Draft of Second Revision released May 1999) Region 1 U.S. Fish and Wildlife Service Portland, Oregon Approved: XXXXXXXXXXXXXXXXXXXXXXXXXX Regional Director, Region 1 U.S. Fish and Wildlife Service Date: XXXXXXXXXXXXXXXXXXXXXXXXXX AR00045352 Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision • May 2005 Disclaimer Recovery plans delineate reasonable actions that are believed to be required to recover and protect listed species. We, the U.S. Fish and Wildlife Service, publish recovery plans, sometimes with the assistance of recovery teams, contractors, State agencies, Tribal agencies, and other affected and interested parties. Objectives will be attained and any necessary funds made available subject to budgetary and other constraints affecting the parties involved, as well as the need to address other priorities. Recovery plans do not obligate other parties to undertake specific actions and may not represent the views nor the official positions or approval of any individuals or agencies involved in recovery plan formulation, other than our own. They represent our official position only after they have been signed by the Regional Director or Director as approved. Recovery plans are reviewed by the public and submitted to peer review before we adopt them as approved final documents. Approved recovery plans are subject to modification as dictated by new findings, changes in species status, and the completion of recovery actions. Notice of copyrighted material: Permission to use copyrighted images in this recovery plan has been granted by the copyright holders. These images are not placed in the public domain by their appearance herein. They cannot be copied or otherwise reproduced, except in their printed context within this document, without the written consent of the copyright holder. Literature citation of this document should read as follows: U.S. Fish and Wildlife Service. 2005. Draft Revised Recovery Plan for Hawaiian Waterbirds, Second Draft of Second Revision. U.S. Fish and Wildlife Service, Portland, Oregon. 155 pp. Electronic copies of this document will be made available at: • http://pacific.fws.goviecoservicesiendangeredirecoveryidefault.htm • http://endangered.fws.govirecovery/index.html AR00045353 Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision • May 2005 Acknowledgments Parts I and II of this recovery plan were drafted in 1997 for the U.S. Fish and Wildlife Service by Andrew Engilis, Jr. (then of Ducks Unlimited, currently of University of California, Davis) and Dr. Frederic A. Reid of the Western Regional Office of Ducks Unlimited. Modifications were made by Dr. Ann Marshall of the U.S. Fish and Wildlife Service, which resulted in the Draft Revised Recovery Plan for Hawaiian Waterbirds Second Revision dated May 1999. Since then, substantial revisions to the draft plan have been made by Leilani Takano and Dr. Eric VanderWerf of the U.S. Fish and Wildlife Service, including the addition of figures illustrating the population trend of each species and maps showing their abundance and distribution on each island. The primary authors of this second draft revised plan are Andrew Engilis, Jr., Dr. Ann Marshall, Dr. Frederic A. Reid, Leilani Takano, and Dr. Eric VanderWerf. For valuable input and constructive comments on waterbird recovery issues we thank J. Michael Reed of Tufts University, Kim Uyehara, Sharon Reilly, and Jennifer Crummer of Ducks Unlimited; Fern Duvall, David Smith, John Polhemus, and Meyer Ueoka of the Hawai' i Department of Land and Natural Resources Division of Forestry and Wildlife; and U.S. Fish and Wildlife Service employees Karen Gabble, Colleen Henson, Nancy Hoffman, Susan Machina, Mark Metevier, Lynda Myashita, Arlene Pangelinan, Gina Shultz, Mike Silbernagle, Gordon Smith, Chris Swenson, Ron Walker, and Marilet Zablan for valuable insights into waterbird recovery needs, assistance with graphics, and review of the recovery plan. We also thank the Hawai' i Division of Forestry and Wildlife for providing the biannual waterbird count data and the Hawai'i Natural Heritage Program for compiling the data. AR00045354 Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision • May 2005 Executive Summary Current Species Status: This second draft revised recovery plan addresses four species of Hawaiian waterbirds: the Hawaiian duck or koloa maoli (Anas wyvilliana), Hawaiian coot or 'alae ke oke' o (Fulica alai), Hawaiian common moorhen or 'alae 'ula (Gallinula chloropus sandvicensis), and Hawaiian stilt or ae' o (Himantopus mexicanus knudseni), all listed as endangered. Historically, these four species were found on all of the main Hawaiian Islands except Lana i and Kaho' olawe. Currently, Hawaiian ducks are found on the islands of NF ihau, Kaua'i, 0' ahu, Maui, and Hawai' i; Hawaiian coots and stilts are found on all of the main Hawaiian Islands except Kaho' olawe; and Hawaiian common moorhens are found only on the islands of Kaua'i and 0' ahu. Population estimates based on the biannual waterbird count indicate the numbers of birds fluctuate among years and that currently none of these species consistently number more than 2,000 individuals, with the exception of the Hawaiian coot, but these estimates are reliable only for the coot and the stilt. Trend data collected over the past three decades show that Hawaiian coot, moorhen, and stilt populations are either stable or increasing. The status of the Hawaiian duck is difficult to judge due to the difficulty of distinguishing between Hawaiian ducks, feral mallards (Anas platyrhynchos), and hybrids. Hawaiian common moorhen numbers are difficult to estimate due to their secretive habits and use of densely vegetated wetland habitats. Habitat Requirements and Limiting Factors: These endangered Hawaiian waterbirds are found in a variety of wetland habitats including freshwater marshes and ponds, coastal estuaries and ponds, artificial reservoirs, taro (Colocasia esculenta) patches, irrigation ditches, sewage treatment ponds, and in the case of the Hawaiian duck, montane streams and swamplands. The most important cause of decline of the four species of endangered Hawaiian waterbirds is loss of wetland habitat. Other factors that have contributed to waterbird population declines, and which continue to be detrimental, include predation by introduced animals, altered hydrology, alteration of habitat by invasive nonnative plants, disease, and possibly environmental contaminants. Hunting in the late 1800's and early 1900's took a heavy toll on Hawaiian duck populations, and to a lesser extent on populations of the other three endemic waterbirds (Swedberg 1967). Currently, predation by introduced animals may be the greatest threat to the coot, moorhen, and stilt, and hybridization with feral mallards is the most serious threat to the Hawaiian duck. Recovery Priority Number: The recovery priority number for the Hawaiian duck is 2, on a scale of 1C (highest) to 18 (lowest; see Appendix D) reflecting a high degree of threat, a high potential for recovery, and the Hawaiian duck's taxonomic rank as a full AR00045355 Second Draft Revised Recovery Plan for Hawaiian Waterbirds, 2nd Revision • May 2005 species. The moorhen and stilt each have a recovery priority number of 9, reflecting a moderate degree of threat, a high potential for recovery, and their taxonomic rank as a subspecies. The recovery priority number of 14 for the Hawaiian coot reflects a low degree of threat, a high potential for recovery, and taxonomic rank as a full species. The Hawaiian coot was considered a subspecies of the American coot (Fulica americana) at the time it was listed, but it was recently split from the American coot and is now regarded as a distinct species (Fulica alai; American Ornithologists' Union 1989). Recovery Goal: The ultimate goal of the recovery program is to restore and maintain multiple self-sustaining populations of these Hawaiian waterbirds within their historical ranges, which will allow them to be reclassified to threatened status and eventually removed from the Federal List of Endangered and Threatened Wildlife and Plants. Recovery Objectives: The recovery of the endangered waterbirds focuses on the following objectives: 1) increasing population numbers to statewide baseline levels (consistently stable or increasing with a minimum of 2,000 birds for each species); 2) establishing multiple, self-sustaining breeding populations throughout each species' historical range; 3) establishing and protecting a network of both core and supporting wetlands that are managed as habitat suitable for waterbirds, including the maintenance of appropriate hydrological conditions and control of invasive nonnative plants; 4) for all four species, eliminating or controlling the threats posed by introduced predators, avian diseases, and contaminants; and 5) for the Hawaiian duck, removing the threat of hybridization with feral mallards. Recovery Criteria: For consideration of downlisting to threatened status, the following conditions must be met: Hawaiian Duck downlisting criteria Criterion 1. All core wetlands