The Gyrfalcon and Tundra Conservation Program
Methods
Aerial Surveys
We conduct helicopter surveys, lead by Alaska Department of Fish and Game, that span approximately 6,500 sq. km and survey roughly 550 cliff nesting sites. These surveys take three full days of flying time and occur twice a year, once to assess how many birds are breeding (occupancy) and again to determine how many your were produced (productivity). This monitoring effort focuses on all cliff nesting raptors and includes Golden Eagles (Aquila chrysaetos), Gyrfalcons (Falco rusticolus), Rough-legged Hawks (Buteo lagopus), Peregrine Falcons (Falco peregrinus), and Common Ravens (Corvus Corax; included as a nest builder and competitor). This effort started in the early 2000s and is among the most important datasets available to us to understand changing population dynamics and altered community structure among Artic raptors. Additinal video credits: Hayden Hutcherson, Travis Booms.
Nest Cameras Installation
We install nest cameras near raptors sites to learn about their diet, behaviors, and to monitor a subset of the population in fine detail (e.g., fine scale nestling mortalities, hatch date and fledge date). These cameras have provided data for three graduate students and two undergraduate students and are a wealth of information for future research as well. All research is conducted with appropriate permits by experienced climbers and raptor handlers. All caution is give to ensure safety of personnel and wildlife. Additional video credits: Devin L. Johnson.
Genotyped Feathers
​
Annual survival is a critical component of population maintenance and there exists no estimates of survival for Gyrfalcons in North America, to the best of our knowledge. Collecting feathers dropped naturally by breeding adults and sampling body feathers from nestlings allows us to perform micro-satellite analysis to genetically identify individuals (genotype), track them over time, and calculate survival and breeding dispersal. From adults, we only collect naturally dropped feathers, minimizing disturbance. We collect nestling feathers by removing two feathers from the back and dry storing them in individual paper envelopes with desiccant. We send feathers to Wildlife Genetics International for genetic analysis. Photo credit: Devin Johnson
Banding/Sample collection​
​
Blood samples provide valuable information about animal physiology, health, and disease ecology. From blood samples we quantify physiological parameters, like stress responses and hematocrit, to reveal sub-lethal effects that can have significant effects for young birds and can be an important indicator of future fitness. We quantify the ratio of heterophils:lymphocytes (H:L; white blood cells) as a composite measure of avian stress that increases with the release of corticosterone and is more sensitive to subtle stimuli. We also quantify hematocrit, the proportion of red blood cells in packed whole blood, to represent the oxygen-carrying capacity of an individual. By collecting these data, we are able to correlate nestling health to important causal agents like inclement weather. To quantify disease-causing pathogens, we sample blood plasma and fecal samples. Disease causing pathogens are encroaching northward and beginning to interact with naïve Arctic wildlife, which can have dramatic effects on populations (Bradley et al. 2005). The Gyrfalcon can serve as an effective indicator species for changes in disease ecology because they are notoriously susceptible to disease and are resident species; indicating that the detected pathogens was transmitted within the Arctic (Radcliff and Henderson 2023). Raptor biologists have indicated that they believe novel pathogens are the most direct and substantial threat to Gyrfalcon populations (Booms personal communication). Video Credit: Travis Booms.
Gyrfalcon Fall Trapping
​
Since 2020, we have been trapping juvenile and adult Gyrfalcons in the fall to test for diseases, since free-flying birds are more likely to contract diseases compared to nestlings. Further, the risk of disease is likely greater in the fall resulting from greater exposure for juveniles and a greater reliance on migratory prey that congregate in large numbers and serve as reservoir hosts for many disease. Additional video/image credits: Travis Booms and Chris Barger
Ptarmigan Surveys
​
Biannually, we drive road transects covering 160 miles of tundra ecosystem to delineate trends in Ptarmigan population dynamics and understand how they affect raptor demographics and diet selection. We started this effort in 2016. Photo credit: Hayden Hutcherson.