Dear members of the MARMAM community, My fifteen co-authors and I are pleased to announce our recent open-access publication in the Journal of Animal Ecology: *Quantitative fatty acid signature analysis reveals a high level of dietary specialization in killer whales across the North Atlantic*. https://doi.org/10.1111/1365-2656.13920 You can find a recap of our main findings aimed at the public, as well as an infographic recap of the paper here: https://whalescientists.com/killer-whales-north-atlantic-diets/. We also created a video abstract here: https://youtu.be/qJh-1XRxTq8 Here is the abstract of the paper: 1- Quantifying the diet composition of apex marine predators such as killer whales (*Orcinus orca*) is critical to assessing their food web impacts. Yet, with few exceptions, the feeding ecology of these apex predators remains poorly understood. 2- Here, we use our newly validated quantitative fatty acid signature analysis (QFASA) approach on nearly 200 killer whales and 900 potential prey to model their diets across the 5,000 km span of the North Atlantic. 3- Diet estimates show that killer whales mainly consume other whales in the western North Atlantic (Canadian Arctic, Eastern Canada), seals in the mid-North Atlantic (Greenland), and fish in the eastern North Atlantic (Iceland, Faroe Islands, Norway). Nonetheless, diet estimates also varied widely among individuals within most regions. This level of inter-individual feeding variation should be considered for future ecological studies focusing on North Atlantic killer whales. 4- These estimates reveal remarkable population- and individual-level variation in the trophic ecology of these killer whales, which can help to assess how their predation impacts community and ecosystem dynamics in changing North Atlantic marine ecosystems. 5- This new approach provides researchers with an invaluable tool to study the feeding ecology of oceanic top predators. Please reach out to me if you have questions/comments. I am also available to collaborate if you wish to test or validate QFASA on other cetacean species or other killer whale populations. You can reach me at anais.remili@mail.mcgill.ca. Cheers, Anais Remili, PhD candidate at McGill University Editor-in-chief of Whale Scientists