Robustly estimating the demographic contribution of immigration: Simulation, sensitivity analysis and seals.

Identifying important demographic drivers of population dynamics is fundamental for understanding life-history evolution and implementing effective conservation measures. Integrated population models (IPMs) coupled with transient life table response experiments (tLTREs) allow ecologists to quantify the contributions of demographic parameters to observed population change. While IPMs can estimate parameters that are not estimable using any data source alone, for example, immigration, the estimated contribution of such parameters to population change is prone to bias.

Killer whale acoustic patterns respond to prey abundance and environmental variability around the Prince Edward Islands, Southern Ocean.

Killer whales are apex predators with temporally and spatially varying distributions throughout the world's oceans. Their ecology and behaviour are poorly understood in most regions due to limited research, often because of logistical challenges. Here, we used a passive acoustic monitoring device to investigate the seasonal acoustic occurrence and diel vocalizing behaviour of killer whales around the remote sub-Antarctic Prince Edward Islands (PEIs), Southern Ocean.

Reproductive phenology is a repeatable, heritable trait linked to the timing of other life-history events in a migratory marine predator.

Population-level shifts in reproductive phenology in response to environmental change are common, but whether individual-level responses are modified by demographic and genetic factors remains less well understood. We used mixed models to quantify how reproductive timing varied across 1772 female southern elephant seals () breeding at Marion Island in the Southern Ocean (1989-2019), and to identify the factors that correlate with phenological shifts within and between individuals. We found strong support for covariation in the timing of breeding arrival dates and the timing of the preceding moult.

The effect of prey abundance and fisheries on the survival, reproduction, and social structure of killer whales () at subantarctic Marion Island.

Most marine apex predators are keystone species that fundamentally influence their ecosystems through cascading top-down processes. Reductions in worldwide predator abundances, attributed to environmental- and anthropogenic-induced changes to prey availability and negative interactions with fisheries, can have far-reaching ecosystem impacts. We tested whether the survival of killer whales () observed at Marion Island in the Southern Indian Ocean correlated with social structure and prey variables (direct measures of prey abundance, Patagonian toothfish fishery effort, and environmental proxies) using multistate models of capture-recapture data spanning 12 years (2006-2018).