Dear MARMAM Community, My co-authors and I are pleased to announce our new publication in Micronesica. This work includes contributions of our late colleague, Tom Norris, who was integral to the project and the drafting of this manuscript. Zoidis, A.M., T.F. Norris, P.A. Olson, T.A. Jefferson, K.S. Lomac-MacNair, S.N. Coates & J.K. Jacobsen. Cetaceans of the nearshore environment at Pagan Island, Commonwealth of the Northern Mariana Islands, Micronesica. 2025-03, 25 pp. Published online 08 September 2025. http://micronesica.org/volumes/2025 ABSTRACT Information on the cetacean fauna found in the nearshore waters of Pagan Island, Commonwealth of the Northern Mariana Islands (CNMI), are reported for the first time. In August 2013 visual and acoustic surveys in the nearshore (< 5.6 kilometers; km [3 nautical miles; nmi]) waters surrounding Pagan Island collected data on cetacean occurrence using line transect (visual and towed acoustic), photo-identification, and moored sonobuoy (passive acoustic monitoring) methods. Three species of cetaceans were visually confirmed at Pagan Island: spinner dolphin (Stenella longirostris), common bottlenose dolphin (Tursiops truncatus), and Cuvier's beaked whale (Ziphius cavirostris). Acoustic encounters included spinner, common bottlenose dolphin, Cuvier's beaked whale, Blainville's beaked whale (Mesoplodon densirostris) and sperm whale (Physeter macrocephalus). The moderately high detection rates of beaked whale species at Pagan can likely be explained by the steep bathymetry and deep-water habitat close to shore. Sperm whales were detected on the acoustic recordings from nighttime moored sonobuoys, indicating their presence within 37 km (20 nmi) of Pagan. On 10 of the 11 research days at Pagan, dolphins were visually or acoustically encountered in the study area, during day and nighttime sampling periods. Photo-identification yielded re-sights of individual spinner dolphins at Pagan Island on successive days. A potential breeding population of bottlenose dolphins was documented at Pagan based on the presence of three calves, including two neonates. The visual and acoustic detection rates for dolphins were relatively low. Caution should be used in interpreting any of the detection rate results due to the small sample sizes. The density or abundance of cetaceans in the study area could not be estimated because of small sample sizes. If future surveys are conducted using similar methods the line transect survey data could be pooled to estimate density and abundance. Our paper is available online: http://micronesica.org/volumes/2025 Or via e-mail request: ann.zoidis@tetratech.com<mailto:ann.zoidis@tetratech.com> Ann M. Zoidis, M.S. | Environmental Project Manager, Senior Biologist, Marine Mammal Scientist Direct: CA Office: 510.302.6358 | ME Office: 207-288-0976 | Cell: 510.393.5906 | Fax: 510.433.0830 ann.zoidis@tetratech.com<mailto:ann.zoidis@tetratech.com> Tetra Tech 1999 Harrison Street, Suite 500 | Oakland, CA 94612 | www.tetratech.com<https://protect2.fireeye.com/url?k=5e2ce27c-020ad5df-5e2e1b49-000babda0106-5bfca81c1c3007de&q=1&u=http%3A%2F%2Fwww.tetratech.com%2F> PLEASE NOTE: This message, including any attachments, may include confidential and/or inside information. Any distribution or use of this communication by anyone other than the intended recipient is strictly prohibited and may be unlawful. If you are not the intended recipient, please notify the sender by replying to this message and then delete it from your system.