Friendly Ground-dove, Tuaimeo Alopecoenas [Gallicolumba] stairi American Samoa Population Species Report May 2020 U.S. Fish and Wildlife Service Pacific Islands Fish and Wildlife Office Honolulu, HI Cover Photo Credits Photograph of first year Friendly Ground-dove, Tuaimeo, Alopecoenas [Gallicolumba] stairi, on the island of Ofu, courtesy of Kimiko Kayano. Suggested Citation USFWS. 2020. Species Status Assessment for the American Samoa Population of the Friendly Ground-dove (Alopecoenas [Gallicolumba] stairi, Tuaimeo). May 2020 (Version 1.1). U.S. Fish and Wildlife Service, Pacific Islands Fish and Wildlife Office, Honolulu, HI. 50 pp Primary Authors Version 1.1 of this document was prepared by Fred Amidon and James Kwon of the Pacific Islands Fish and Wildlife Office, Honolulu, Hawaii. Preparation and review was conducted by Gregory Koob, Megan Laut, and Stephen E. Miller of the Pacific Islands Fish and Wildlife Office. Acknowledgements We would like to thank N. Arcilla, C. Caruso, and T. Togia for providing information on the threats to the Friendly Ground-dove. We would especially like to thank K. Kayano and P. Pyle, Institute for Bird Populations for use of their Friendly Ground-dove photographs. ii Executive Summary The Friendly Ground-dove or Tuaimeo (Alopecoenas [Gallicolumba] stairi) is a medium-sized dove native to the Samoan, Fijian and Tongan archipelagos and Wallis and Futuna Islands. The American Samoa population of the Friendly Ground-dove was listed as endangered and a Distinct Population Segment (DPS) under the Endangered Species Act in 2016. Historically and currently, this DPS is restricted to the islands of Ofu and Olosega in American Samoa. Population trend information is unavailable, but the ground-dove has persisted in small numbers (< 100 individuals) since at least the late 1970s. The primary threats to this DPS are habitat loss and degradation, increased nest failure, and reduced juvenile survival. Habitat loss and degradation is attributed several sources: human development (e.g., agriculture); an increase in the distribution and number of invasive plant species and feral ungulates; and forest impacts from naturally occurring tropical cyclones (hurricanes). Increased nest failures and reduced juvenile survival are attributed to nest predation by introduced rats, depredation of juveniles by feral cats, and nest loss due to naturally occurring tropical cyclones (hurricanes). This Species Report evaluates the viability of the Friendly Ground-dove DPS, defined as the likelihood that it will persist over time. Viability is assessed by the resiliency, representation, and redundancy of the Friendly Ground-dove DPS in American Samoa. Each of these terms, and the DSP’s resultant viability, under current conditions are described below. Resiliency is the capacity of a population to withstand stochastic disturbance events. Currently and historically the species was only recorded on the islands of Ofu and Olosega at low numbers, with more birds sighted on Ofu. The resiliency of the Ofu population is considered to be low to moderate while the Olosega population is low. Both of these resiliency ratings are based on the limited distribution of the species in the DPS and their low numbers. These rankings are expected to continue or decline if the threats to the species continue at current levels or worsen. Representation is having one or more populations of a species occupying the full range of habitat types used by the species. There are no historical population estimates for the Fiendly Ground- Dove. Currently, the American Samoa DPS is considered to have moderate to high representation due to its consistent range and habitat use. However, the range of this DPS is expected to decline if the threats to the species continue at current levels or worsen, resulting in decreasing representation and increased risk to its resiliency and redundancy. Redundancy is minimizing the risk of extinction of the species by establishing multiple populations across a landscape so some populations will always survive catastrophic events. Currently, the species is considered to have low redundancy as the species occurs in only two, closely spaced populations in the DPS. Redundancy is expected to decrease in the future if threats to the species continue at current levels or worsen, potentially resulting in the extirpation of one or both of the two remaining populations. iii Table of Contents Cover Photo Credits ........................................................................................................................ ii Suggested Citation .......................................................................................................................... ii Primary Authors .............................................................................................................................. ii Executive Summary ....................................................................................................................... iii List of Figures ..................................................................................................................................v List of Tables ................................................................................................................................. vi Introduction ......................................................................................................................................1 Regulatory History ...........................................................................................................................2 Methodology ................................................................................................................................ 2 Part 1. Life History and Historical Status ........................................................................................5 Geography ................................................................................................................................... 5 Species Description ................................................................................................................... 11 Life History................................................................................................................................ 13 Historical Range, Distribution, and Population Status .............................................................. 17 Part 2. Current Conditions and Species Status...............................................................................21 Current Range and Distribution ................................................................................................. 21 Factors Affecting Viability ........................................................................................................ 22 Resiliency, Representation, and Redundancy of the Species ........................................................29 Resiliency of Current Populations ............................................................................................. 29 Current Representation and Redundancy of the Species ........................................................... 30 Literature Cited ..............................................................................................................................32 iv List of Figures Figure 1. Samoa, Fiji, and Tonga archipelagos and Wallis and Futuna Islands. ............................ 1 Figure 2. The three conservation biology principles of resiliency, redundancy, and representation, or the “3Rs”. ........................................................................................................... 3 Figure 3. Islands and political entities of the Samoan archipelago. ................................................ 5 Figure 4. Monthly mean precipitation for selected areas of the Samoan archipelago. All data PCCSP (2019). ................................................................................................................................ 6 Figure 5. Monthly mean temperatures for selected areas of the Samoan archipelago. All data PCCSP (2019). ................................................................................................................................ 7 Figure 6. Cyclone (hurricane) tracks for the central South Pacific from 1898 to 2019. All data from Knapp et al. (2010) and NOAA IBTrACS (2019). ................................................................ 7 Figure 7. Locations of roads in the Samoan archipelago. ............................................................... 8 Figure 8. Map of vegetation on American Samoa. Developed from data by Meyer et al. (2017). ....................................................................................................................................................... 10 Figure 9. Photographs of an adult male (A) and female (B) Friendly Ground-dove from American Samoa. All photos by the Institute of Bird Populations. .............................................. 12 Figure 10. Breeding cycle of the Friendly Ground-dove. All data based on Baptisa et al. 1997 (pp. 180-186), Myers (2002, p.11), and Kremer et al. (2014, pp. 70-71). .................................... 15 Figure 11. Generalized life stages of the Friendly Ground-dove. ................................................. 17 Figure 12. The estimated historic range of the Friendly Ground-dove. Locations are based on Watling (2001, p. 118). ................................................................................................................