Killer whale () population dynamics in response to a period of rapid ecosystem change in the eastern North Atlantic.

This study investigates survival and abundance of killer whales () in Norway in 1988-2019 using capture-recapture models of photo-identification data. We merged two datasets collected in a restricted fjord system in 1988-2008 (Period 1) with a third, collected after their preferred herring prey shifted its wintering grounds to more exposed coastal waters in 2012-2019 (Period 2), and investigated any differences between these two periods. The resulting dataset, spanning 32 years, comprised 3284 captures of 1236 whales, including 148 individuals seen in both periods.

Decline in abundance and apparent survival rates of fin whales () in the northern Gulf of St. Lawrence.

Estimates of abundance and survivorship provide quantifiable measures to monitor populations and to define and understand their conservation status. This study investigated changes in abundance and survival rates of fin whales () in the northern Gulf of St. Lawrence in the context of anthropogenic pressures and changing environmental conditions.