Gyrfalcon Health in Alaska: A Temporal and Spatial Assesment of the Risk of Emergent Diseases for an Artic Specialist in a Dramatically Changing Climate

Principal Investigator: Robin Radcliffe

Department of Clinical Sciences
Sponsor: John T. and Jane A. Wiederhold Foundation
Title: Gyrfalcon Health in Alaska: A Temporal and Spatial Assesment of the Risk of Emergent Diseases for an Artic Specialist in a Dramatically Changing Climate
Project Amount: $44,998
Project Period: September 2020 to August 2021

DESCRIPTION (provided by applicant): 

Accelerated climate change in the Arctic is exposing wildlife to an array of emerging threats including the northern expansion of pathogens that are novel to Arctic specialists. The Gyrfalcon (Falco rusticolus), a top avian predator and true Arctic specialist, is among the most vulnerable bird species to climate change due in part to their limited genetic variability and the rapid changes to their circumpolar range. Arctic temperatures are increasing at ca. twice the global average, which can alter local disease ecology and expose Gyrfalcons to pathogens to which they lack defenses. These changes to Gyrfalcon habitat may tip the balance of health and disease in favor of pathogens through changes in vector distribution, host ranges and pathogen life cycles. Warmer Arctic temperatures and accompanied landscape changes may also impact the Gyrfalcon’s prey base, and dietary habits can influence transmission of pathogens. Additionally, captive Gyrfalcons are exceptionally susceptible to novel pathogens, suggesting they are a viable model species to investigate the prevalence and virulence of pathogens in the Arctic. We selected a suite of disease agents of critical importance to the health of Gyrfalcons [haemosporidian blood parasites– avian malaria (Plasmodium species) and leucocytozoons; viral and bacterial pathogens; and endoparasites (Capillaria and Eimeria sp.)] since transmission of these pathogens is likely to expand across Arctic and subarctic Alaska as the Arctic warms. Many viral, bacterial and endoparasitic diseases are transmitted by direct exposure and through predation of infected hosts, whereas Flaviviruses such as West Nile as well as avian blood parasites are transmitted primarily by vectors (mosquitos and black flies). Our broad objective is to evaluate Gyrfalcon vulnerability to disease in their changing climate in western Alaska, using two complimentary disease survey approaches: (1) compare molecular and immunological disease prevalence data in archival Gyrfalcon blood samples with samples collected as part of this study; and (2) examine the link between raptor diet and prevalence of disease by comparing two Gyrfalcon populations differing in their dietary ecology—one breeding on the Seward Peninsula feeding primarily on nonmigratory prey (ptarmigan & squirrel) and the other in southwestern Alaska in the Aleutian Islands feeding on migratory prey (waterfowl). This unique partnership between academia, a non-profit raptor conservation organization and a state game agency will help define the current disease status of the world’s largest falcon as a reflection of changing habitat and prey base in the Arctic ecosystem and provide insight into an important and understudied aspect of global climate change.