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Project Information

The biocomplexity project is divided into subprojects, each of which focuses on a different aspect of introduced avian disease.

Contents


Administration
Contact Person: David Cameron Duffy
Phone: (808) 956-8218

Project: If you have questions about the project, please mail

David Cameron Duffy
Professor of Botany and Unit Leader
Pacific Cooperative Studies Unit (PCSU)
Department of Botany
University of Hawaii
3190 Maile Way St. John 410
Honolulu, HI 96822-2279

Current Personnel: David C. Duffy (Principal Investigator)

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Food Resources
Contact Person: Paul Banko
Phone: 808--967-7396 ext. 235

Project: The role of food availability in constraining Hawaiian forest bird populations has not been investigated as extensively as disease and predation, but there are valid reasons to believe that it affected populations historically and continues to do so presently. Native insects, including Lepidoptera, have suffered greatly from alien predators and parasites, including biocontrol agents intended for pests of sugarcane and pasture grasses. While it is likely that changes in food availability have influenced the distribution and abundance of Hawaiian forest birds, food availability is also likely to affect the exposure and susceptibility of birds to disease. Birds that track the availability of nectar, fruit, and seeds over large areas may enter regions where mosquitoes and disease transmission occur. For example, Apapane track flowering ohia lehua trees along elevation gradients and over large tracts of forest. Ou and Alala once tracked fruit. Palila track mamane seeds. Birds that may be nutritionally stressed, especially growing nestlings and juveniles, may suffer the effects of malaria and pox to a greater degree than robust individuals. Conversely, diseased individuals may be less capable of foraging.

The Food Resources Subproject is investigating 1) what foods, especially insects, are used by birds in different study sites throughout the year, and what resources are most likely to limit bird populations, 2) whether food availability differs among study sites and over the course of the year, 3) whether birds more susceptible to diseases when critical food resources are less available and they are nutritionally stressed, 4) whether the Japanese White-Eye, the most common non-native forest bird in Hawaii, competes with native birds for food resources, and 5) whether birds produce more fledglings in areas where food resources are more available.



Current Personnel: Paul Banko (Principal Investigator)
Robert Peck (Food Resource Biologist)

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Host Demographics
Contact Person: Bethany L. Woodworth
Phone: 207-799-7805

Project: In 2002, the Host Demography Subproject began full-scale sampling of forest bird communities in 9 study areas distributed along an elevational gradient from 15 to 1700 m on the eastern flank of Mauna Loa Volcano, Hawaii. Forest bird sampling was conducted using two complementary techniques, mist-netting and bird censusing (variable-circular plot counts). In addition, we also studied the phenology of ohia (Metrosideros polymorpha), the primary canopy tree in Hawaiian forests, and the primary nectar source for several birds of concern in this study. The phenology of ohia across the landscape is thought to drive daily long-distance foraging flights by apapane (Himatione sanguinea) and iiwi (Vestiaria coccinea), with implications for the disease system.

Current Personnel: Bethany W. Woodworth (Principal Investigator)

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Host Genetics
Contact Person: Rob Fleischer or Sue Jarvi
Phone: 808-974-7358 (Jarvi), or 202-673-4842(Fleischer)

Project: We are assessing genetic variation in several species of host birds across the Biocomplexity Project field sites to document differences between populations normally subject to malarial infection (low elevation) versus those that are not (high elevation). We are looking at both functional genes (i.e., Mhc, G6PDH) that could be directly involved in malaria resistance, and also likely neutral genetic markers (microsatellites, AFLP, mtDNA). The latter markers are used for a variety of purposes: they may be linked to important functional genes; their use in population structure analyses can tell us about gene flow and population histories; and they are important markers for assessing species and individual identifications from mosquito blood meals. We are also examining these same genetic markers in birds which have survived or not survived malarial challenge experiments.

Current Personnel: University of Hawaii at Hilo:
Susan I. Jarvi (Principal Investigator)
Margaret Farias (Graduate Student)
Kim Weigand (Project Specialist)
Alexis Giannoulis (Student Intern)

Smithsonian Institution:
Robert C. Fleischer (Principal Investigator)

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Modeling
Contact Person: Michael Samuel, Andrew Dobson, Jorge Ahumada
Phone: 608-270-2441 (Samuel); 609-258-1334 (Dobson); 608-270-2458 (Ahumada)

Project: Information generated by the biocomplexity project will be integrated in a computer modeling framework which will be used to simulate and forecast the dynamics of the system and to evaluate broad hypothesis on how biocomplexity associated with biotic and abiotic components affects the persistence of disease in forest bird populations. The model will also allow us to simulate how changes in land use and environmental conditions affect the stability of the system, and how habitat changes and specific conservation strategies might alter long-term trends in the decline and extinction of the endemic Hawaiian avifauna.

Current Personnel: At National Wildlife Health Center:
Michael Samuel (Principal Investigator)
Francisco de Castro (Post-doctoral Researcher)

At Princeton University:
Andrew Dobson (Principal Investigator)

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Pathogen Genetics
Contact Person: Sue Jarvi, Rob Fleischer, Dina Fonseca
Phone: 808--967-7396 ext. 269; 202-673-4842; 215-299-1177

Project: Both avian pox virus and malaria were introduced to Hawaii and it is unclear what level of genetic diversity exists in these pathogens and whether it is correlated with possible phenotypic differences in host specificity or virulence. The pathogen genetics subproject is 1)looking at diversity of ribosomal and TRAP (a sporozoite cell surface molecule) sequences from isolates of malaria here in Hawaii, 2) developing microsatellite markers for Plasmodium relictum for studies of parasite population struction 3) developing PCR assays for avian pox virus and investigating genetic diversity of selected sequences, and 4) attempting to establish a possible date for the introduction of these pathogens through analysis of museum skins dating back to the turn of the century.

Current Personnel: At University of Hawaii-Hilo:
Susan I. Jarvi (Principal Investigator)
Margaret Farias (Graduate Student)

At Smithsonian Institution:
Robert C. Fleischer (Principal Investigator)
Dina Fonseca (Principal Investigator)

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Pathogens
Contact Person: Carter T. Atkinson
Phone: 808-967-8119, ext. 271

Project: The Pathogens Subproject seeks to develop a more detailed understanding of the biological characteristics of avian malaria (Plasmodium relictum) and avian pox virus (Poxvirus avium) - two disease agents that were introduced into Hawaiian forest bird populations. Goals of this subproject include 1) providing diagnostic information and analysis for all blood samples collected from the 9 biocomplexity study sites, 2) determining whether low elevation native birds are developing genetic resistance to malaria through experimental aviary infections, 3) determining whether genetically distinct malarial isolates from different elevations and areas differ in virulence or other life history traits, 4) developing improved diagnostic methods for avian pox virus, 5) characterizing different pox virus isolates from native and non-native forest birds by genetic methods, 6) determining the susceptibility and role that non-native forest birds may play as disease reservoirs through experimental aviary studies, 7) determining host range and virulence of genetically distinct pox virus isolates from the 9 study areas, 8) determining how dual or sequential infections of avian pox and malaria interact and affect morbidity and mortality of native forest birds through experimental aviary studies.

Current Personnel: Carter T. Atkinson (Principal Investigator)

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Vector
Contact Person: Dennis LaPointe
Phone: 808--967-7396 ext. 273

Project: Mosquito vectors are the central component to this disease system linking the pathogens with the host. They are also the component most greatly impacted by human activity and therefore, perhaps, the key in controlling these diseases. To address many of the vector related questions we monitor and sample mosquito populations across our study landscape. Monthly mosquito trapping provides data on species composition, infection status and estimates of relative abundance, seasonality, and survivorship. Surveys on study sites document the abundance and nature of larval mosquito habitat and its relationship to feral pig and/or human activites. As climate has such a profound effect on mosquito abundance and potential to vector disease, weather stations at each elevation collect detailed data on precipitation, canopy and ground temperature, wind speed and wind direction. Laboratory experiments will determine possible variation in the innate ability of vectors to acquire and transmit disease and differences in hosts' mosquito-avoidance behavior and the subsequent success of mosquito blood-feeding. All these parameters relate to the intensity of disease transmission across the landscape and through time.

Current Personnel: Dennis LaPointe (Principal Investigator)

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Vector Genetics
Contact Person: Dina Fonseca
Phone: 215 299 1177 (1195 lab)

Project: Our group is examining fine-scale population genetic structure of the southern house mosquito, Culex quinquefasciatus, within and among the Biocomplexity Project study sites, and more generally across the island of Hawaii. Our aim is to describe spatial population structure, source-sink population dynamics, and movement patterns of this vector of avian disease. To this end, we have developed and are applying highly variable microsatellite DNA markers for population studies in this species. We are particularly interested in the extent to which various aspects of landscape structure, including elevation, the presence of human settlements, and feral pig habitat, affect mosquito population structure and movement. These results will have implications for how land-use patterns may determine disease dynamics in populations of native Hawaiian birds.

Current Personnel: Dina Fonseca (Principal Investigator)

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This material is based upon work supported by the National Science Foundation under Grant No. 0083944 and by the U.S. Geological Survey, Invasive species and wildlife programs. Any opinions, findings and conclusions expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation or the U.S. Geological Survey.

The Biocomplexity Project thanks the following organizations for their support:
United States Geological Survey, University of Hawaii at Manoa, University of Hawaii at Hilo, Smithsonian Institution, Princeton University, and many other collaborators
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