Dear MARMAM community, My co-authors and I are pleased to inform you about a new publication titled “Spatial and temporal distribution patterns of marine mammals in the southern Sea of Okhotsk around Hokkaido, Japan” recently published in Regional Studies in Marine Science. Furumaki, S., Li, H., Suzuki, M., Mitani, Y. (2026). Spatial and temporal distribution patterns of marine mammals in the southern Sea of Okhotsk around Hokkaido, Japan. Regional Studies in Marine Science 95: 104853. https://doi.org/10.1016/j.rsma.2026.104853 Abstract Conserving biodiversity and ecosystems require continuous monitoring to ensure effectiveness, and marine mammals serve as effective biodiversity indicators. The southern Sea of Okhotsk around Japan are waters with high biodiversity and conservation importance. Determining the comprehensive spatial-temporal distribution of marine mammals can be used as a baseline to identify critical habitats. This study aimed to reveal the spatial- temporal distribution patterns of marine mammals using a ship-based sighting survey and species distribution models. Between spring and fall, three baleen whale species, six toothed whale species, and one pinniped species were identified. Baleen whales, killer whales, and Dall’s porpoises appeared primarily in spring, followed by sperm whales appeared in summer, and Pacific white-sided dolphins appeared in fall. Maximum entropy models were developed for six species, revealing heterogeneous spatial patterns. Fin and minke whales were concentrated on the western side of the Shiretoko Peninsula. Sperm and killer whales were distributed on both sides in deep and steep slope waters. Dall’s porpoise occurs more frequently in deeper waters and Pacific white-sided dolphins in shallow waters, with both species being distributed across the study area. By combining ship- based sighting surveys with species distribution models, it was possible to evaluate spatial distributions, including unobserved areas on the western side of the Peninsula. Different species occupy distinct marine regions, highlighting that not only the waters around the Shiretoko Peninsula, a World Natural Heritage Site extending 3 km offshore around the Shiretoko Peninsula, but also the surrounding waters are crucial for marine mammals. The paper can be freely accessed until 3 April 2026 via the publisher ShareLink: https://authors.elsevier.com/a/1mbym8MvAu7TN0 <https://kwnsfk27.r.eu-west-1.awstrack.me/L0/https:%2F%2Fauthors.elsevier.com%2Fa%2F1mbym8MvAu7TN0/1/0102019c53fafe63-4e950385-be94-43fd-ab15-c73cb29efb30-000000/5NqQV-ryOXt98lYFwsSWoKdRHx8=465> Please feel free to contact us if you have any questions. Best regards, Shiho Furumaki Japan Fisheries Research and Education Agency Mail: furumaki96@gmail.com