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Robert J. Shallenberger

Bio: Robert J. Shallenberger is an academic researcher. The author has contributed to research in topics: Hemignathus & Population. The author has an hindex of 1, co-authored 1 publications receiving 27 citations.

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Journal Article
TL;DR: Because the Alaka'i studies were seminal in the development of the current AOU classification of Hawaiian native passerines, they defend that classification against recent challenges and further refine it.
Abstract: We observed, tape recorded, and photographed birds of the Alaka'i Plateau on Kaua'i, Hawai'i for one week during the summer of 1975. We observed all but one of the island's historically known species and compared the Alaka'i Plateau with the more accessible Koke'e area. Ours were the last studies before catastrophic changes in the Kaua'i avifauna and included many observations that cannot now be repeated. This retrospective report presents our findings in the light of subsequent events. Because our Alaka'i studies were seminal in the development of the current AOU classification of Hawaiian native passerines, we defend that classification against recent challenges and further refine it. The controversial genus Hemignathus is shown to be supported by a suite of synapomorphies of plumage, bill morphology, and vocalizations. We advocate removal of the 'Anianiau from Hemignathus and classify it as Magumma parva. Our studies of foraging behavior and vocalizations support the recent recognition of the Kaua'i 'Amakihi (H. kauaiensis) as a separate species and suggest that the 'Elepaio (Chasiempis) is best split into three species (sckzteri, ibidis, and sandwichensis). Major hurricanes in 1983 and 1992 appear to have severely impacted Alaka'i bird populations with the subsequent extinction of the Kaua'i '0'0 (Moho braccatus) and possibly the Kama'o (Myadestes myadestinus), and the island population of 'O'u (Psittirostra psittacea). We report some of the last natural history observations on these species. Formerly adaptive strategies for storm survival, including taking refuge in valleys, are no longer effective because the lowlands are now infested with mosquito-borne avian diseases. The Puaiohi (M. palmen'), a ravine specialist, suffered less from the storms although its population remains perilously low. Other forest birds, especially the 'Akikiki (Oreomystis bairdi), show noticeable declines since 1975. We speculate that intro- duced organisms such as alien plants can have a deleterious effect on ecosystems by altering feeding methods of birds even in areas where the weeds do not occur. We caution against the overly conservative use of species- level taxa for setting conservation priorities on remote islands. Received 24 October 19%, accepted 27 June 1997.

29 citations


Cited by
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Journal ArticleDOI
01 Jul 1997-The Auk
TL;DR: The Auk, Vol.
Abstract: The Auk, Vol. 127, Number 3, pages 726−744. ISSN 0004-8038, electronic ISSN 1938-4254.  2010 by The American Ornithologists’ Union. All rights reserved. Please direct all requests for permission to photocopy or reproduce article content through the University of California Press’s Rights and Permissions website, http://www.ucpressjournals. com/reprintInfo.asp. DOI: 10.1525/auk.2010.127.3.726. R. TeRRy ChesseR,1,12,13 RiChaRd C. Banks,1 F. keiTh BaRkeR,2 CaRla CiCeRo,3 Jon l. dunn,4 andRew w. kRaTTeR,5 iRBy J. loveTTe,6 Pamela C. Rasmussen,7 J. v. Remsen, JR.,8 James d. Rising,9 douglas F. sToTz,10 and kevin winkeR11

100 citations

Journal ArticleDOI
01 Jul 2004-The Auk
TL;DR: The results obtained allowed us to assess the importance of knowing the total number of birds in North and Middle America, not just the number of individuals, as well as the distribution of these birds in the region.
Abstract: 1 U.S. Geological Survey, Patuxent Wildlife Research Center, National Museum of Natural History, Washington, DC, USA 2 Alexandria, Virginia, USA 3 Museum of Vertebrate Zoology, University of California, Berkeley, California, USA 4 Bishop, California, USA 5 Florida Museum of Natural History, University of Florida, Gainesville, Florida, USA 6 Cornell Laboratory of Ornithology, Ithaca, New York, USA 7 Museo de Zoologia, Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, Mexico 8 Michigan State University Museum and Department of Zoology, East Lansing, Michigan, USA 9 Museum of Natural Science, Louisiana State University, Baton Rouge, Louisiana, USA 10 Department of Ecology and Evolutionary Biology, Ramsay Wright Labs, University of Toronto, Toronto, Ontario, Canada 11 Environment, Culture and Conservation, Field Museum of Natural History, Chicago, Illinois, USA 12 University of Alaska Museum, Fairbanks, Alaska, USA * Corresponding author: chessert@si.edu; Chairman of the Committee on Classification and Nomenclature—North and Middle America, of the American Ornithologists’ Union. All authors are members of the Committee and are listed alphabetically after the Chairman.

98 citations

Journal ArticleDOI
TL;DR: Increasing mean air temperatures, declining precipitation, and changes in streamflow that have taken place over the past 20 years are creating environmental conditions throughout major portions of the Alaka'i Plateau that support increased transmission of avian malaria.
Abstract: Transmission of avian malaria in the Hawaiian Islands varies across altitudinal gradients and is greatest at elevations below 1500 m where both temperature and moisture are favorable for the sole mosquito vector, Culex quinquefasciatus, and extrinsic sporogonic development of the parasite, Plasmodium relictum. Potential consequences of global warming on this system have been recognized for over a decade with concerns that increases in mean temperatures could lead to expansion of malaria into habitats where cool temperatures currently limit transmission to highly susceptible endemic forest birds. Recent declines in two endangered species on the island of Kaua’i, the ‘Akikiki (Oreomystis bairdi) and ‘Akeke’e (Loxops caeruleirostris), and retreat of more common native honeycreepers to the last remaining high elevation habitat on the Alaka’i Plateau suggest that predicted changes in disease transmission may be occurring. We compared prevalence of malarial infections in forest birds that were sampled at three locations on the Plateau during 1994–1997 and again during 2007–2013, and also evaluated changes in the occurrence of mosquito larvae in available aquatic habitats during the same time periods. Prevalence of infection increased significantly at the lower (1100 m, 10.3% to 28.2%), middle (1250 m, 8.4% to 12.2%), and upper ends of the Plateau (1350 m, 2.0% to 19.3%). A concurrent increase in detections of Culex larvae in aquatic habitats associated with stream margins indicates that populations of the vector are also increasing. These increases are at least in part due to local transmission because overall prevalence in Kaua’i ‘Elepaio (Chasiempis sclateri), a sedentary native species, has increased from 17.2% to 27.0%. Increasing mean air temperatures, declining precipitation, and changes in streamflow that have taken place over the past 20 years are creating environmental conditions throughout major portions of the Alaka’i Plateau that support increased transmission of avian malaria.

90 citations

Journal ArticleDOI
TL;DR: Kaua’i represents an early warning for the forest bird communities on the Maui and Hawai‘i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing.
Abstract: The viability of many species has been jeopardized by numerous negative factors over the centuries, but climate change is predicted to accelerate and increase the pressure of many of these threats, leading to extinctions. The Hawaiian honeycreepers, famous for their spectacular adaptive radiation, are predicted to experience negative responses to climate change, given their susceptibility to introduced disease, the strong linkage of disease distribution to climatic conditions, and their current distribution. We document the rapid collapse of the native avifauna on the island of Kaua‘i that corresponds to changes in climate and disease prevalence. Although multiple factors may be pressuring the community, we suggest that a tipping point has been crossed in which temperatures in forest habitats at high elevations have reached a threshold that facilitates the development of avian malaria and its vector throughout these species’ ranges. Continued incursion of invasive weeds and non-native avian competitors may be facilitated by climate change and could also contribute to declines. If current rates of decline continue, we predict multiple extinctions in the coming decades. Kaua‘i represents an early warning for the forest bird communities on the Maui and Hawai‘i islands, as well as other species around the world that are trapped within a climatic space that is rapidly disappearing.

73 citations

Journal ArticleDOI
TL;DR: The monophyly and phylogeny of the adaptive radiation of Hawaiian finches were studied using parsimony analysis of comparative osteology and Templeton tests of alternative phylogenetic hypotheses, providing a framework for incorporating morphological and palaeontological information in evolutionary studies of the Drepanidini.
Abstract: The monophyly and phylogeny of the adaptive radiation of Hawaiian finches (Fringillidae: Drepanidini; honeycreepers, auct.) were studied using parsimony analysis of comparative osteology, combined with Templeton (Wilcoxon signed-ranks) tests of alternative phylogenetic hypotheses. Eighty-four osteological characters were scored in 59 terminal taxa of drepanidines, including 24 fossil forms, and in 30 outgroup species. The optimal phylogenetic trees show considerable agreement, and some conflict, with independently derived ideas about drepanidine evolution. The monophyly of a large Hawaiian radiation was upheld, although one fossil taxon from Maui fell outside the drepanidine clade. The finch-billed species were placed as basal drepanidine taxa, and continental cardueline finches (Carduelini) were identified as the radiation’s closest outgroups. The study found anatomical as well as phylogenetic evidence that the radiation had a finch-billed ancestor. The optimal trees identify the red-and-black plumage group as a clade, and suggest that the tubular tongue evolved only once in the radiation. Because comparative osteology provides too few characters to strongly support all the nodes of the tree, it was helpful to evaluate statistical support for alternative hypotheses about drepanidine relationships using the Templeton test. Among the alternatives that received significant statistical support are a relationship of the drepanidines with cardueline finches rather than with the Neotropical honeycreepers (Thraupini), classification of the controversial genera Paroreomyza and Melamprosops as drepanidines, and a secondary loss of the tubular tongue in Loxops mana. The hypothesis of monophyly for all the Hawaiian taxa in the study was not rejected statistically. The study provides a framework for incorporating morphological and palaeontological information in evolutionary studies of the Drepanidini. © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society, 2004, 141, 207‐255. ADDITIONAL KEYWORDS: adaptive radiation ‐ comparative anatomy ‐ evolution ‐ fossils ‐ Hawaiian honeycreepers ‐ island biogeography ‐ morphology ‐ palaeontology ‐ Passeriformes.

62 citations