UC San Diego

Killer whales produce pulsed calls, which are used for communication. Calls are highly stereotyped and repertoires are unique to individual pods. Discrimination amongst these calls and comparison of call repertoires between pods can help determine population structure in killer whales and can be used to track pod movements. Calls were detected in underwater acoustic recordings in August and September 2017 in the Arctic waters of Eclipse Sound, in Nunavut, Canada. We present a repertoire of killer whale calls recorded. Eleven stereotypic call types, three biphonic and eight monophonic, were identified using manual call organization and manual whistle contour extraction. A higher diversity of calls was detected in the hydrophone located in the known narwhal aggregation site in Milne Inlet, than at the second hydrophone deployed at the mouth of Eclipse Sound which is the proposed entrance and exit point for the killer whales. The potential for increased killer whale presence and magnitude of predation on narwhals is a source of concern for management of the population and by Inuit subsistence hunters who rely on narwhals for food and economic benefit. Describing the acoustic repertoire of killer whales seasonally present in the Canadian Arctic may help understand their behavior and seasonal movements. The results presented may provide a basis for future acoustic comparisons across the North Atlantic and aid in characterizing killer whale ecotypes making seasonal incursions into Arctic waters.