Premier Presentation: From island to subarctic populations: What role do vectors play in the transmission of avian malaria in a naive avifauna?

What can be learned from investigations conducted on the epizootiology of avian malaria (Plasmodium) parasites on the Galápagos and Hawaiian islands? Avian populations have been declining as a direct result of the immunological and geographical isolation from regular exposure to these haemosporidian parasites. Thus, naïve populations have been shown to be particularly vulnerable to the pathogenic effects of invasive parasites. A successful invasion and establishment of Plasmodium spp. in a naïve avifauna is dependent on the species composition of the vector population.  However, the role of vectors in the transmission of avian malaria parasites and their importance in the structuring of Plasmodium-host relationships is currently understudied. This knowledge gap poses a series of risks to naïve avian populations that are experiencing invasion events, especially to avian species that are already facing conservation challenges. Here, I present the avian malaria disease risk predictions for the endemic avian populations on Socorro Island, Mexico, and in the subarctic region of Alaska, USA. Using California-based vector competence studies as a guideline, I will discuss how vectors are structuring Plasmodium-host relationships by serving as both a compatibility filter and as an encounter filter. These are extremely important entomological considerations that must be included in a wildlife conservation and management plan, failure to neglect this component in disease risk assessments could result in the collapse of a fragile endemic avian population.