Work

Sea ice dynamics structure narwhal presence and seasonal movements in a Northwest Greenland fjord system

Year: 2026

Type: article

Abstract: The Arctic is experiencing unprecedented environmental change, with diminishing sea ice reshaping marine ecosystems. The narwhal (Monodon monoceros) exhibits strong site fidelity during seasonal movements and continued sea-ice decline has the potential to alter important habitats. This study aimed to understand narwhal presence at different sea-ice stages by combining long-term passive acoustic monitoring (PAM) with satellite-derived sea ice data from Inglefield Bredning, Northwest Greenland (June 2022-September 2025). Generalized linear mixed models (GLMMs) revealed a highly significant effect of sea-ice stage on narwhal acoustic activity (p < 0.001). Activity peaked during partial ice cover (β = 1.73 ± 0.17, p < 0.001) but declined sharply under open-water and freeze-up conditions (β = - 0.98 ± 0.19, p < 0.001). These results demonstrate that narwhal presence is closely synchronized with sea-ice timing and extent, emphasizing the marginal ice zone as a key ecological feature that narwhals exploit, likely because it provides both feeding opportunities and refuge from predators. Continued loss of seasonal sea ice is therefore expected to alter narwhal movement patterns, potentially increasing fjord residency and reducing inter-fjord movements. Such behavioural shifts could have cascading ecological effects, altering prey dynamics and reducing genetic exchange among regional narwhal groups.

Source: Scientific Reports

DOI: 10.1038/s41598-026-53787-8

Authors: Julie Sofie K. Larsen, Michael Ladegaard, Peter T. Madsen, Steffen M. Olsen, Malene Simon

Institutions: Aarhus University, Grønlands Naturinstitut, Danish Meteorological Institute

Language: English

Topic: Marine animal studies overview

Subfield: Ecology

Field: Environmental Science

Domain: Physical Sciences

SDGs: Life below water, Climate action

Open Access status: gold

Estimated APC paid: $2,690