Avian Malaria/Pox

The Iiwi is one of the colorful Hawaiian forest birds threatened by avian malaria.

 

Accidental introduction of mosquito-borne avian malaria and pox virus to Hawaii provides an outstanding example of how introduced diseases can have a profound effect on endemic biota.

Co-infection with avian malaria and pox complicates the population health challenges to Hawaii’s forest birds.

The geographic distribution, density, and community structure of endemic Hawaiian avifauna has changed dramatically in the last century, in large part because of the spread of these diseases and their introduced mosquito vector.  This disease system is dynamic and biologically complex, involving both direct and indirect interactions among endemic and introduced avian hosts, mosquito vector, parasites, and environmental conditions that extend across multiple temporal and spatial scales. An integrated, multi-disciplinary research project is studying the demography of exotic and endemic forest birds, mosquito vectors, and pox and malaria parasites across a range of climate, hydrology, and vegetation patterns. Within this project Dr. Samuel leads a holistic modeling effort designed to study this complex system by integrating across scales ranging from the gene to the landscape.

A microscopic image of the avian malaria parasite – Plasmodium relictum.

This modeling effort will be used to integrate the diversity of research studies being conducted within the overall project and to evaluate broad hypotheses about the dynamics of the Hawaiian forest bird ecosystem, including how biocomplexity associated with biotic and abiotic components at multiple scales affect persistence of the disease.  Complementary field and laboratory studies are being conducted by other investigators that focus on genetic variation of hosts, vectors and parasites and epidemiological factors such as host susceptibility and resistance, parasite virulence and vectors competency.

Introduced feral pigs are just one of the biotic factors creating challenges for malaria management in the Hawaiian ecosystem.

When feral pigs feed on tree fern trunks they make ruts that create ideal water cavities for mosquito breeding – maintaining a strong malaria vector population.

 

 NSFlogoThis work is part of the larger Biocomplexity Project studying introduced avian diseases in Hawaii.  This is a large interdisciplinary and multi-institutional project funded by the National Science Foundation.

People

Michael D. Samuel, PhD
(Lab Leader)

 

Joy Rose, PhD
(Postdoc)

 

Peter Hobbelen, PhD
(Former Postdoc)

 

Publications

Hobbelen, P. H. F., M. D. Samuel, D. A. LaPointe, and C. T. Atkinson.  Modeling future conservation of Hawaiian honeycreepers by mosquito management and translocation of disease-tolerant Amakihi.  PLos ONE 7(11): e49594. doi:10.1371/journal.pone.0049594.

Hobbelen, P. H. F., M. D. Samuel, D. Foote, L. Tango, and D. A. LaPointe.  2012.  Modeling the impacts of global warming on predation and biotic resistance: mosquitoes, damselflies, and avian malaria in Hawaii.  Theoretical Ecology.  DOI 10.1007/s12080-011-0154-9.

LaPointe, D. A., C. T. Atkinson, and M. D. SAMUEL.  2012.  Ecology and conservation biology of avian malaria.  Annals of the New York Academy of Sciences 1249:211-226.

Paxton, E. H., J. Burgett, E. McDonald-Fadden, E. Bean, C. T. Atkinson, D. Ball, C. Cole, L. H. Crampton, J. Kraus, D. A. LaPointe, L. Mehrhoff, M. D. SAMUEL, D. C. Brewer, S. J. Converse, and S. Morey.  2012.  Keeping Hawai’i’s Forest Birds One Step Ahead of Avian Diseases in a Warming World: a focus on Hakalau Forest National Wildlife Refuge:  A Case Study from the Structured Decision Making Workshop, February 28-March 4, 2011, Hawai’i Volcanoes National Park, Hawaii USA. 

Hart, P. J., B. L. Woodworth, R. Camp, K. Turner, K. McClure, K. Goodall, C. Henneman, C. Spiegel, J. LeBrun, E. Tweed, J. Citta, and M. Samuel.  2011.  Bird and resource variability across and elevational gradient in Hawaii.  The Auk 128:113-126.

Samuel, M. D., P. H. F. Hobbelen, F. DeCastro, J. A. Ahumada, D. A. LaPointe, C. T. Atkinson, B. L. Woodworth, P. J. Hart, and D. C. Duffy. 2011. The dynamics, transmission, and population impacts of avian malaria in native Hawaiian birds: a modeling approach. Ecological Applications 21:2960-2973.

Atkinson, C.A., and M.D. Samuel. 2010. Avian Malaria (Plasmodium relictum) in Native Hawaiian Forest Birds: Epizootiology and Dempgraphic Impacts on Apapane (Himatione sanguinea). Journal of Avian Biology 41:357-366.

Ahumada, J. A., M. D. Samuel, D. C. Duffy, A. Dobson, and P. H. F. Hobbelen.  2009.  Modeling the epidemiology of avian malaria and pox Hawaii.  Page 331-335 in Conservation Biology of Hawaiian Forest Birds.  T. K. Pratt, C. T. Atkinson, P. C. Banko, J. Jacobi, and B. L. Woodworth (eds.). Yale University Press, New Haven.

Woodworth, B. L. et al. 2005. Biocomplexity of introduced Avian Diseases in Hawaii. Threats to biodiversity of native Forest Ecosystems. Fact Sheet