Do You Want to See Polynesian Birds? American Samoa Won't
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National Park Service Pacific Island Network U.S. Department of the Interior Pacific pigeon of purple-capped fruit doves appear Do You Want to See Polynesian Birds? stable in both units which may be NPSA Landbird American Samoa Won't Disappoint. attributed to the species' generalist diet. Survey We expect the 2011 The National Park of American Samoa The wattled honeyeater (Foulehaio distribution 2,516 bird (NPSA) contains the only paleotropical carunculata) was the most conspicuous, of landbirds in rainforest in the U. S. National Park widespread, and abundant species in NPSA to fluctuate detections System. The forest's native birds (and both units with an estimated population over time, fruit bats) are major pollinators and of almost 150,000 birds. A generalist particularly in Banded rail seed dispersers that drive ecological and aggressive forager, this species has areas where processes throughout the Samoan taken advantage of NPSA’s numerous birds frequent 13 detected Archipelago. Their importance to these flowering plants and perhaps forces 13 native species because of foraging forests is profound. other birds, such as the cardinal opportunities. Birds Purple swamphen honeyeater (Myzomela cardinalis), of landbirds tend to follow their 7 detected Agriculture, hunting, logging, to forage in areas closer to villages. food sources, and development, and the introduction naturally, the availability of numerous alien species have had In both park units, the Polynesian of fruit and nectar is Many-colored fruit-dove negative effects on bird populations. starling (Aplonis tabuensis), Samoan dependent on plant 16 detected The birds have also suffered periodic starling (Aplonis atrifusca), collared distributions and weather declines as a result of the high frequency kingfisher (Halcyon chloris), Pacific events.The bird sampling Purple-capped fruit-dove of very destructive hurricanes in the pigeon(Ducula pacifica) and purple- The field team takes a breather after stations used in the 2011 338 detected archipelago. Protection of large sections capped fruit-dove (Ptilinopus a long morning of bird counts survey were broadly of native rainforest, such as in NPSA, porphyraceus) occurred in modest to distributed throughout has been a great benefit to Samoa’s high densities (see sidebar). The banded NPSA, so we consider Blue-crowned lorikeet native birds. rail (Gallirallus philippensis) and purple our estimates to be a good 101 detected swamphen (Porphyrio porphyrio) representation of species Our landbird monitoring team surveyed occurred in low densities (14 and 7 abundance. White-rumped swiftlet NPSA's forests for birds and habitat detections, respectively). Both of these characteristics from June through species, which travel and forage on the This survey also provides 87 detected August, 2011. The survey area was forest floor, may be vulnerable to attacks of these storms, there were less than 50 solid baseline information on landbird comprised of the terrestrial portions of by cats and dogs. many-colored fruit-doves (Ptilinopus distribution and density in the park. Collared kingfisher the Ta‘u and Tutuila Units of the park. perousii) on all of Tutuila Island in The survey will be repeated every five 73 detected Point-transect distance sampling was Unique to the Manu‘a Islands (a group 1995 according to the American Samoa years to detect trends for these bird used to estimate bird abundance. of islands that inlcude Ta'u Island), the Department of Marine and Wildlife populations. Long-term monitoring of blue-crowned lorikeet (Vini australis) Resources (1996). These doves appear to the landbirds and associated habitats Fiji shrikebill We detected a total of 2,516 birds occurred in modest densities, about still be struggling. On the other hand, the of NPSA will help managers ensure 15 detected and 13 species in the park. All species 9,400, within the boundaries of NPSA collared kingfisher, wattled honeyeater, that the unique and colorful birds of are either endemic or indigenous to on Ta‘u. It is also worth noting that and purple-capped fruit-dove have American Samoa will continue to paint Samoan starling American Samoa. Nearly every species only 15 Fiji shrikebills (Clytorhynchus shown stronger signs of recovery. The wattled these tropical landscapes. 354 detected detected was broadly distributed in the vitiensis) were detected on Ta‘u. In honeyeater predominantly native forests of NPSA. addition, there were no detections of was the most In our surveys, the many-colored fruit- The National Park of American Samoa For seven species, a sufficient number the spotless crake (Porzana tabuensis), abundant dove was detected in very low numbers; offers excellent opportunities to Polynesian starling of detections were made to allow us perhaps the rarest landbird in American species however, this species is known to be detected in observe Polynesian birds for scientists 187 detected to make density estimations for those Samoa. the survey. patchily distributed. Opportunities and visitors alike. species (how many birds per hectare). to observe and collect distribution The team Cardinal honeyeater Encouragingly, bird population As we surveyed, we were reminded that estimates information on this species depends on –S. Judge, Wildlife biologist, CESU estimates from our surveys were similar the archipelago is under constant threat nearly 43,000 the availability of fruits, especially Ficus 17 detected to or higher than previous island-wide from destructive hurricanes, which have on Tutuila species. In addition, on Ta‘u the dove surveys on both Tutuila and Ta‘u islands. caused significant periodic declines of Island and may have been negatively impacted by more than Wattled honeyeater every landbird species. Hurricane Tusi the recent Hurricanes Heta in 2004 and 105,000 1111 detected in 1987, Hurricane Ofa in 1990, and individuals on Olaf in 2005. Densities of the majority the very severe Hurricane Val in 1991, Ta‘u. (photo of landbirds detected on Ta'u were caused catastrophic losses to human by Emily lower than estimates from Tutuila, which Pacific pigeon structures, as well as stripped foliage off Weiser). was not as severely impacted by those Collared 197 detected kingfisher large areas of native forests. As a result hurricanes. In contrast, populations Cardinal honeyeater Featured Resource March 2012.