Dear Marmam community, On behalf of my co-authors, I am happy to announce the publication of our recent paper in Mammalian Biology: "Adapting photo‑identification methods to study poorly marked cetaceans: a case study for common dolphins and harbor porpoises" Full view-only access to the article can be found here: https://rdcu.be/cKKEK This article is a contribution to the special issue on “Individual Identification and Photographic Techniques in Mammalian Ecological and Behavioural Research – Part 1: Methods and Concepts” — Editors: Leszek Karczmarski, Stephen C.Y. Chan, Daniel I. Rubenstein, Scott Y.S. Chui and Elissa Z. Cameron. Abstract: Historically, traditional photo-identification (photo-ID) methods have been applied to cetaceans with relatively small group sizes, closed and/or small populations, distinctive dorsal fin nicks and/or notches and behavior allowing for photographic capture. Conversely, species with larger group and/or population sizes that often occur in open populations, which have less distinctive natural markings and/or whose behavior is prohibitive for photographic capture, have not been the focus of many photo-ID studies. We review two successful photo-ID studies on species that have less distinctive markings, but differ in habitats and behavior: (1) common dolphins (Delphinus delphis) that live in oceanic environments, have large group sizes, occur in open populations and are easily observed and (2) harbor porpoises (Phocoena phocoena) that live in coastal environments, have small group sizes, but are behaviorally cryptic and elusive. We discuss how traditional photo-ID methods were adapted by incorporating different: (1) identification sides; (2) identification features; (3) levels of photo quality (PQ); (4) distinctiveness and; (5) methods for error checking. Adaptations include: using symmetry of the identification features to determine if both sides of the animal are used, using more than one identification feature, developing a matrix for describing/ sorting by the identification features, using three levels of distinctiveness, incorporating PQ and distinctiveness into a flowchart to identify distinctively marked individuals (DMIs) and applying a more rigorous review process to identify possible errors in cataloguing. We discuss how adapting traditional photo-ID methods will improve our ability to use photo-ID for species not traditionally studied using this method. Feel free to contact me with any questions. Best, Cindy Cindy Elliser, PhD Research Director Pacific Mammal Research www.pacmam.org 360-202-2860