Title: Ecology and demography of killer whales in the eastern Canadian ArcticWho: Fisheries and Oceans CanadaWhat: Our killer whale field research program has been ongoing since 2009, developed in consultation with Inuit communities about their growing concerns about increasing killer whale presence around their communities. Our planned research program over the upcoming three years (2026-2029) is a continuation of this long-term project, with specific objectives regarding killer whale demographics and predator impacts. Core field work methods including satellite tagging, biopsy, and photo-identification will be used, as well as newer methods including drone recordings of behaviour, body composition, and group composition.[1] Satellite tag deployment: Killer whales will be slowly approached by boat to within 10 m. Satellite tags will be deployed onto the dorsal fin using crossbows, using metal darts to anchor the tag below the skin. Tags will transmit location and dive data up to 300 times daily as the whale surfaces to satellites. Tags using this technique typically last several weeks on killer whales, but have lasted for up to ~120 days. Telemetry data will be used to better understand killer whale distribution and migration patterns.[2] Biopsy: Skin and blubber biopsies will be collected using crossbows or an airgun to fire sterile stainless steel biopsies near the saddle patch (just behind the dorsal fin). Biopsied skin and blubber will be frozen for genetic and chemical analyses (e.g., stable isotopes and fatty acids). Genetics analyses will provide information on killer whale group and population structure, as well as evidence of gene expression in response to local adaptation to Arctic conditions. The microchemistry analyses will provide information on both diet and distribution.[3] Photo-identification: Killer whales will be photographed using digital SLR cameras. Individual killer whales have unique natural features (dorsal fin shape and size, scarring, and saddle patch and eye-patch shape) that can be used to identify them. Photo-identification has been used to match killer whale movements between different areas and therefore understand their distribution. Estimates of killer whale abundance will be updated using statistical models that compare the rates of newly identified and re-sighted whales.[4] Acoustic recordings and behavioural observations: Killer whale calls will be recorded using dip hydrophones from the research boat (i.e., not at the seafloor). At the same time, killer whale behavior will also be recorded using drones from a distance of approximately 300-1000 m for up to 30 minutes per session/focal group. Killer whale behaviors will be evaluated and analysed to better understand correlations between behavior and call type, which will be the first step to using passive acoustic recorders to monitor killer whale presence and activity (e.g., predation) in the Canadian Arctic.[5] Aerial photographs: Aerial photographs taken by drones will be analysed to assess killer whale body size and condition. Aerial photographs may also be used to determine reproductive status (e.g., pregnant females) and demographic information (e.g. group composition, pregnancy rates) for comparison among years to assess growth trends.One of the main goals of our Arctic killer whale research has been to develop scientific research capacity in northern communities. Inuit beneficiaries hired to conduct field research receive training in deploying satellite transmitters, biopsying and storing tissues, photography, and data entry. We typically hire up to five local research assistants and rent local equipment (e.g., boats) for our field work, as we work to establish a network of independent, Inuit-led research teams throughout the region.Why: Killer whales are important predators in marine ecosystems worldwide. Increases in killer whale sightings in the eastern Canadian Arctic over the past decades, most likely associated with decreases in sea ice extent and duration, have raised concerns about their ecological impacts on Arctic ecosystems. Killer whales in the eastern Canadian Arctic prey on marine mammals (narwhal, beluga, bowhead whales, and seals). Greater killer whale predation pressure on ecologically, culturally, and economically valuable marine mammal populations could impact their sustainable use for food by Inuit/Northerners. Moreover, our previous research has shown that killer whale presence alone can drastically alter the distribution and movements of prey species. There is therefore growing concern among Inuit communities that increasing killer whale presence in the Arctic may have adverse impacts on Arctic-endemic marine mammals. Several Inuit communities have asked for population assessments to determine whether killer whale populations can be sustainably harvested or culled. To understand how killer whales in the eastern Canadian Arctic impact populations of marine mammals that are harvested by Inuit, we need more information about their population structure, abundance and population trends, and ecology (e.g., distribution, movements, diet, and hunting behaviour) in the region.Where: Admiralty Inlet (Arctic Bay).When: Generally August, although possibly from July through September when killer whales are seasonally present and weather conditions allow for boat-based field work. Multi-year project (2026-2029).