© 2015 by Griffith Wildlife Disease Ecology Group

 

Avian malaria

 

Avian malaria and related parasites belong to a globally distributed group of vector-transmitted intracellular blood parasites (Haemosporida; transmitted primarily by mosquitoes and biting midges).  

 

As is the case in humans, these parasites can cause severe problems for infected birds (Valkiūnas 2005) and have therefore been suggested as model agents to study the affects of parasitism on the distributions and life-history characteristics of their hosts (Ricklefs 2010).

 

Using recently developed molecular techniques (DNA extractions from avian blood) and traditional parasitology methods (microscopy of blood smears), our lab is involved in several projects to describe the diversity, distribution and ecological impacts of avian malaria parasites in south Pacific birds.

 

Specifically, we are aiming to

 

  • Identify ecological and environmental determinants of parasite colonisation and persistence on small islands [using Heron Island, QLD as a model system; (Clark et al. 2014a)].

  • Contribute to and utilise global datasets of parasite genetic lineages [MalAvi database; (Bensch et al. 2009)] to describe large scale patterns in parasite diversity and distribution (Clark et al. 2014b)

  • Investigate patterns of parasite pressure and their potential influence on host divergence across islands in the New Caledonia archipelago

  • Describe spatial gradients in parasite pressure and how they relate to host migration strategies for long-distance migratory shorebirds

  • Identify the roles that invasive species can play to influence prevalence patterns of parasites in native bird species (using the Indian Myna in southeast QLD in and northeast NSW as a model system)

 

Funding

 

These projects have been partly funded by research grants from BirdLife Australia and Birds Queensland (to N. Clark for Australia field and labwork) and the National Geographic Society (to S. Clegg for New Caledonia field and labwork).

 

Image credit: Nick Clark

Image credit: Nick Clark

Collaborators include

 

  • Dr. Sonya Clegg, Oxford University

  • Professor Marcel Klaassen, Deakin University

  • Dr. Rob Adlard, Queensland Museum

  • Dr. Rohan Clarke and Dr. Anders Concalves da Silva, Monash University

 

Useful references for avian malaria

 

Bensch, S., O. Hellgren, and J. Perez-Tris. 2009. MalAvi: a public database of malaria parasites  

     and related haemosporidians in avian hosts based on mitochondrial cytochrome b lineages.

     Molecular Ecology Resources 9:1353-1358.

 

Clark, N. J., R. D. Adlard, and S. M. Clegg. 2014a. First evidence of avian malaria in Capricorn

     Silvereyes (Zosterops lateralis chlorocephalus) on Heron Island. The Sunbird 44:1-11.

 

Clark, N. J., S. M. Clegg, and M. R. Lima. 2014b. A review of global diversity in avian

     haemosporidians (Plasmodium and Haemoproteus: Haemosporida): new insights from

     molecular data. International Journal for Parasitology 44:329-338.

 

Ricklefs, R. E. 2010. Evolutionary diversification, coevolution between populations and their

     antagonists, and the filling of niche space. Proceedings of the National Academy of Sciences

     107:1265-1272.

 

Valkiūnas, G. 2005. Avian malaria parasites and other haemosporida. CRC Press, Boca Raton,

     Florida.

Image credit: Nick Clark