November 2025 - MARMAM - devlists.uvic.ca

New publication - Steller sea lion (Eumetopias jubatus) consumption of ocean age-0 Chinook salmon (Oncorhynchus tshawytscha) along the northwest coast of Washington State
by Adrianne Akmajian 13 Nov '25

13 Nov '25

Dear MARMAM community, On behalf of my co-authors, I am pleased to share a new open access publication entitled: Steller sea lion (*Eumetopias jubatus*) consumption of ocean age-0 Chinook salmon (*Oncorhynchus tshawytscha*) along the northwest coast of Washington State. Abstract: The decline of wild Chinook salmon (*Oncorhynchus tshawytscha*) in the Pacific Northwest is concerning due to their critical role in the culture, economy, and ecology of the region, and the endangered species status of some of the evolutionarily significant units. Decline in Chinook stocks has been partially attributed to increases in pinniped abundance. The northwest coast of Washington State, USA, provides year-round habitat to early marine-phase Chinook salmon from multiple stocks and habitat for increasingly abundant Steller sea lions (*Eumetopias jubatus*). We estimated the Chinook salmon biomass consumed by Steller sea lions along the northwest coast of Washington using diet data obtained via DNA metabarcoding from scat and a prey consumption model. Between December 2020 and August 2021, Steller sea lions consumed 284 metric tons (95% PI: 191–417 t) of Chinook salmon. A set of experimental models were used to estimate the consumption of age-0 Chinook salmon, and the base model estimated 146 t (95% PI: 93–221 t) of ocean age-0 Chinook—or approximately 2,064,418 (95% PI: 1,431,524–2,932,922) individual ocean age-0 Chinook— were consumed during the study period. While precise consumption values should be interpreted with caution due to high uncertainty highlighted by sensitivity analyses, our results suggest that Steller sea lions contribute to the low marine survival rates of early marine-phase Chinook salmon at a higher rate than previously estimated. The high uncertainty in model estimates, compounded by assumptions and limitations arising from data gaps, highlights the need for further research on both predator and prey populations in the region. Citation: Lewis ZK, Nelson BW, Akmajian AM, Scordino JJ, Allyn EM, Brown S, Schwarz D, and A Acevedo-Gutiérrez. 2025. Steller sea lion (*Eumetopias jubatus*) consumption of ocean age-0 Chinook salmon (*Oncorhynchus tshawytscha*) along the northwest coast of Washington State. PLoS One 20(11): e0334612. https://doi.org/10.1371/journal.pone.0334612 Adrianne Akmajian Marine Ecologist/ Marine Ecology Division Manager Makah Tribal Organization Phone: (360) 645-3079 Cell: (505) 385-9528 E-mail: marine.ecologist(a)makah.com Website: www.makah.com Office Hours: Monday-Thursday, 8:00 AM – 5:00 PM (Closed for lunch 12:00 – 1:00 PM) *Note: Office hours may vary by department.*

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Unlock the Power of Marine Mammal Community Data: Multivariate Analysis of Ecological Communities Using VEGAN
by Oliver Hooker 13 Nov '25

13 Nov '25

*Unlock the Power of Marine Mammal Community Data:Multivariate Analysis of Ecological Communities Using VEGAN* https://prstats.org/course/multivariate-analysis-of-ecological-communities-… Marine ecosystems are complex, dynamic, and species-rich—yet challenging to analyse due to patchy detections, wide-ranging movements, variable survey effort, and multi-species interactions. Whether you work on cetacean community structure, pinniped foraging assemblages, acoustic species guilds, or broad-scale biodiversity responses to environmental change, robust multivariate tools are essential. This five-day live online course provides a comprehensive, applied introduction to multivariate analysis using the widely adopted R package *vegan*, with direct relevance to the types of community-level data common in marine mammal science. ------------------------------ What the course covers *Handling ecological community data* Learn how to prepare species-by-site matrices, manage heterogeneous survey data, transform variables, and compute distance measures suited to acoustic detections, transect data, or encounter rates. *Diversity indices and community metrics* Compute and interpret measures such as richness, Shannon diversity, evenness, and species-abundance distributions—useful for assessing community shifts in response to climate, noise, fishing pressure, or habitat change. *Clustering, classification, and ordination* Master PCA, NMDS, RDA, CCA and other techniques to explore patterns in multi-species occurrence data, identify community guilds, detect spatial structure, and quantify ecological gradients in marine systems. *Environmental drivers and gradients* Integrate predictors such as oceanography, bathymetry, prey indices, anthropogenic disturbance, or temporal trends to uncover relationships between marine mammal communities and their environments. *Reproducible analysis workflows in R* Build transparent, publication-ready scripts for analysis, visualisation, and interpretation, enabling consistent workflows across projects and teams. ------------------------------ Why this matters for marine mammal research Marine mammal datasets are often high-dimensional, sparse, and strongly influenced by environmental gradients. This course equips you to: - Identify ecological structure in multi-species detection data - Quantify shifts in community composition across space, seasons, or environmental conditions - Analyse acoustic or visual survey data at a community level - Detect species assemblages, guilds, or habitat associations - Build robust, defensible workflows for conservation and management reporting - Produce ordination and diversity outputs widely used in ecological publications and marine monitoring programmes >From broad-scale biodiversity assessments to targeted multi-species studies, the tools taught in this course help you make sense of complex marine ecological data. ------------------------------ Who should attend Ideal for marine mammal ecologists, conservation practitioners, environmental consultants, MSc/PhD students, and data analysts working with community-level datasets. A basic understanding of R is recommended, including data import, manipulation, and foundational statistics. ------------------------------ Format & practicalities - Five days of live online teaching (approximately 7 hours per day) - Bring your own datasets if you wish; instructors will help tailor methods to your project - All sessions recorded and available for later review - Fee: £485 ------------------------------ *Take the next step in your analytical journey* If you are ready to deepen your understanding of community-level patterns in marine mammal ecology and move beyond simple summaries into powerful multivariate inference, this course provides the structured, practical training you need. -- Oliver Hooker PhD. PR stats

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Advance Your Marine Mammal Research with Bayesian Multilevel Modelling
by Oliver Hooker 13 Nov '25

13 Nov '25

------------------------------ *Advance Your Marine Mammal Research with Bayesian Multilevel Modelling* https://prstats.org/course/bayesian-multilevel-modelling-using-brms-for-eco… Marine mammal science increasingly relies on sophisticated statistical tools to extract robust insights from complex datasets. From photo-identification studies and acoustic monitoring to telemetry and population assessments, the challenges are clear: hierarchical structure, imperfect detection, sparse sightings, zero inflation, individual heterogeneity, spatial dependence, and non-Gaussian responses. To meet these analytical demands, PR Stats is offering: *Bayesian Multilevel Modelling using brms for Ecologists (BMME02)* A 5-day, live online workshop designed for researchers who want to apply modern Bayesian approaches to real ecological data using the *brms* package in R. Developed by ecologists for ecologists, this course provides the skills, understanding, and confidence needed to analyse the kinds of messy, hierarchical, and data-limited systems that define marine mammal research. ------------------------------ What you will learn *Fundamentals of Bayesian inference* Understand priors, posteriors, credible intervals, and how Bayesian reasoning supports transparent and reproducible ecological modelling. *Fitting and interpreting multilevel models in brms* Learn to build models that reflect the real structure of your data, such as repeated sightings of individuals, nested sampling designs, varying detection effort, or multi-year monitoring programs. *Best practices for model evaluation* Develop rigorous habits in posterior predictive checking, residual diagnostics, and model comparison, ensuring your conclusions are well supported. *Tools for zero-inflated, overdispersed, and imperfect detection data* Marine mammal datasets often contain many zeros, sparse detections, or uneven coverage. You will learn to use model families and structures that address these challenges directly. *Application to your own research* Throughout the course, there is a strong emphasis on practical implementation. You will gain experience applying the tools to ecological case studies and be guided on how to adapt these methods to your own datasets and research goals. ------------------------------ Why this course is especially useful for marine mammal researchers Marine mammal ecology routinely involves: - *Photo-ID datasets* with repeated observations of individuals, varying capture probabilities, and long-term resight histories. - *Passive acoustic monitoring* with count, presence–absence, or detection-based outputs that are often zero-inflated. - *Telemetry and movement data* that require hierarchical structures and careful modelling of individual variability. - *Abundance and distribution surveys* with spatially structured effort and imperfect detection. - *Long-term monitoring* where temporal autocorrelation and multilevel variation are central features of the data. Bayesian multilevel models provide a principled framework for analysing all of these data types. The *brms* package allows you to fit sophisticated hierarchical models while writing code that is clear, expressive, and accessible to non-specialists. This course teaches you how to build models that reflect ecological reality, quantify uncertainty, and communicate results with clarity. Whether your work focuses on population dynamics, distribution modelling, acoustic behaviour, or conservation assessments, the tools gained here will allow you to tackle complex analyses with confidence and rigour. ------------------------------ Spaces are limited. Secure your place today and expand your ability to model, interpret, and understand ecological data in marine mammal research. *Register here <https://prstats.org/course/bayesian-multilevel-modelling-using-brms-for-eco…>* -- Oliver Hooker PhD. PR stats

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PhD/Postdoctoral Positions Available at Aquatic Animal Virtopsy Lab, City University of Hong Kong
by Prof. KOT Brian Chin Wing 13 Nov '25

13 Nov '25

PhD/Postdoctoral Positions Available at Aquatic Animal Virtopsy Lab (AAVL - https://bit.ly/AAVLab) City University of Hong Kong (CityUHK) Project Title: Aquatic Animal Biological Health and Profile Assessment Using Multidisciplinary Approach Research Area and Project Description In the bustling marine crossroads of Hong Kong and its adjacent South China Sea waters―an epicentre of rapid urbanisation, heavy maritime traffic, and intensifying climate pressures―cetaceans and sea turtles emerge as vital sentinels of oceanic and human health under the “One Ocean, One Health” framework. Since 2014, the AAVL has pioneered the world’s first routine application of postmortem imaging and virtopsy to stranded cetaceans and sea turtles, establishing a globally recognised standardised protocol. This has yielded over a decade of high-fidelity, cross-platform data encompassing imaging, pathology, toxicology, nutrition, and demographics―forming a robust regional benchmark for health profiling and threat forecasting. This PhD/postdoctoral project harnesses this unparalleled longitudinal archive to decode how cumulative stressors―chemical contaminants, shifting prey dynamics, emerging pathogens, and climate-driven environmental shifts―disrupt growth, immunity, and reproductive viability in these umbrella species. By translating individual-level virtopsy insights into population-scale biomarkers, the research will empower predictive modelling of emerging threats, inform real-time conservation interventions (e.g., marine protected area design, pollution mitigation), and guide evidence-based policy to safeguard biodiversity and coastal community livelihoods across the Greater Bay Area and beyond. Successful candidates will have flexibility to tailor sub-projects to their expertise and interests, working within a multidisciplinary team that integrates virtopsy, forensic pathology, diagnostic imaging, genetics, and bioinformatics. Required Qualifications (PhD) Candidates must meet CityUHK’s minimum entrance requirements for Doctor of Philosophy (PhD): * A Bachelor’s degree with first-class honours (or equivalent) from a recognised university; OR * A Master’s degree (or equivalent) from a recognised university; OR * A higher degree by research (or equivalent); OR * Current CityUHK MPhil students seeking transfer to PhD candidature. English Proficiency (for applicants whose entrance qualification is from a non-English institution): * TOEFL ≥79 (internet-based, single sitting); OR * IELTS ≥6.5 overall; OR * Equivalent (e.g., CET-6 ≥490); scores valid within 2 years of application. Some departments/colleges may impose higher standards. Added Advantages: * Strong background in genetics and bioinformatics. * Adequate knowledge of forensic pathology and diagnostic imaging. Desirable Qualifications (PhD & Postdoc) * MSc/MPhil (or higher) in marine biology, veterinary science, ecology, bioinformatics, or related fields. * Peer-reviewed publications (especially first-author). * Experience with postmortem examination, tissue sampling, biomarker assays, or large datasets. * Proficiency in R/Python, statistical modelling, or machine learning. * Excellent written/oral communication and teamwork skills. Supervision & Location The candidate will be supervised by Prof Brian Kot and the AAVL team at CityUHK, a globally ranked institution with state-of-the-art virtopsy and imaging facilities. PhD Application Deadlines & Process * Main Round (2026/27 intake): 1 December 2025 (12:00 noon HKT) * Applications accepted year-round; early submission encouraged for outstanding candidates. To Apply PhD: Submit via CityUHK’s online portal (https://www.cityu.edu.hk/pg/research-degree-programmes/apply-now) 1. Cover letter outlining motivation and fit with the project. 2. CV (including GPA, publications, and relevant experience). 3. Brief research proposal (max 2 pages). 4. Official transcripts and degree certificates. 5. English proficiency scores (if applicable). 6. Contact details of two academic referees. 7. Application fee. Shortlisted candidates will be invited for interview (in-person or online). Funding: Competitive CityUHK PhD studentships eligibility. Postdoctoral positions include salary commensurate with experience. Start Date: Flexible (PhD - earliest July 2026; latest September 2026; Postdoc - earliest March 2026). Contact To apply postdoc position, please submit application to Prof Brian Kot (email: brian.kot(a)cityu.edu.hk<mailto:brian.kot@cityu.edu.hk>) directly for review, with cover letter and updated CV. Applications will receive full consideration until the position(s) is filled and only shortlisted applicants will be contacted. For PhD informal enquiries, you are encouraged to contact Prof Brian Kot (email: brian.kot(a)cityu.edu.hk<mailto:brian.kot@cityu.edu.hk>). Full application guidelines: https://www.cityu.edu.hk/pg/research-degree-programmes/steps-and-procedures Act fast and join us in pioneering virtopsy-driven conservation science at the heart of Asia’s world city! Warm regards, Brian Kot On behalf of the Aquatic Animal Virtopsy Lab Ph.D. in Diagnostic Imaging, B.Sc. (Hons) in Radiography, Cert. (RPC), CAS (Forensic Imaging & Virtopsy) Assistant Professor Department of Infectious Diseases and Pubic Health Jockey Club College of Veterinary Medicine and Life Sciences City University of Hong Kong T: (852) 3442 7681 E: briankot(a)cityu.edu.hk W: https://www.cityu.edu.hk/ph/staff/dr-brian-kot-chin-wing Aquatic Animal Virtopsy Lab Website: https://bit.ly/AAVLab Follow us at Facebook: https://www.facebook.com/AAVLab2014 Instagram: https://www.instagram.com/aavlab2014 X: https://x.com/aavlab2014 Disclaimer: This email (including any attachments) is for the use of the intended recipient only and may contain confidential information and/or copyright material. If you are not the intended recipient, please notify the sender immediately and delete this email and all copies from your system. Any unauthorized use, disclosure, reproduction, copying, distribution, or other form of unauthorized dissemination of the contents is expressly prohibited.

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Epigenetic Clock for Common Dolphins, new paper
by Evi Hanninger 13 Nov '25

13 Nov '25

Dear colleagues, My coauthors and I are excited to announce our new open-access publication reporting the first species-specific epigenetic clock for common dolphin (Delphinus delphis), developed entirely from stranded and bycaught individuals using dental ageing as the calibration framework. Our results show that discrepancies between dental and epigenetic ages in older dolphins do not reflect dental ageing error, and that decomposition state (DCC 1–3) had no effect on the accuracy of methylation-based age estimates, demonstrating the robustness of post-mortem samples for clock development. Hanninger, E.-M. F., Peters, K. J., Gerber, L., Barratclough, A., Betty, E. L., Palmer, E. I., Horvath, S., & Stockin, K. A. (2025). “ Dental Ageing Offers New Insights Into the First Epigenetic Clock for Common Dolphins (Delphinus delphis).” Ecology and Evolution 15, no. 11: e72424. https://doi.org/10.1002/ece3.72424. Abstract: Determining exact age in wild odontocetes is essential for understanding population dynamics, survival, and reproduction, yet remains logistically challenging. Although epigenetic ageing is emerging as a valuable approach, only nine species-specific clocks currently exist. Most have been calibrated using known-age animals in human care or well-studied wild populations. Only three previous studies have used dental ages from stranded or bycaught individuals. This is due to concerns that dental age inaccuracies, especially in older animals, may affect epigenetic clock performance. To explore this, we developed the first species-specific epigenetic clock for common dolphins (Delphinus delphis), analysing DNA methylation at 37,492 cytosine-phosphate-guanine sites in skin samples from stranded and bycaught dolphins with estimated dental ages. Elastic net models with Leave-One-Out Cross-Validation were applied to three subsets: the ‘relaxed’ subset (all individuals; n = 75, median absolute error (MAE) = 2.02, r = 0.81, R2 = 0.66), the ‘strict’ subset (excluding individuals with minimum dental age estimates only; n = 73, MAE = 2.29, r = 0.81, R2 = 0.66), and the ‘restricted’ subset (excluding outliers with prediction errors > 6 years; n = 63, MAE = 1.80, r = 0.91, R2 = 0.82) to compare performance. Our models consistently underestimated the age of dolphins > 16 years, even when minimum dental ages were applied, suggesting that absolute errors between dental and epigenetic estimates are unlikely to reflect the dental ageing error. Additionally, post-mortem decomposition condition code (DCC 1 to 3) did not affect age prediction, signalling promise for future epigenetic clocks calibrated with strandings and bycaught individuals. Best regards, Evi Hanninger

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New publication: Stranding data can significantly bias marine mammal habitat suitability models
by Meirelles, Carol 12 Nov '25

12 Nov '25

Dear colleagues, My co-authors and I are happy to share a new open access publication on the use of stranding data in marine mammal habitat modelling. Meirelles, A.C.O., Normande, I.C., Alves, M.D.O., Choi, K.F., Carvalho, V.L., Borges, J.C.G., Trites, A.W. 2026. Stranding data can significantly bias marine mammal habitat suitability models. Ecological Modelling, 512, 111394. https://doi.org/10.1016/j.ecolmodel.2025.111394 https://www.sciencedirect.com/science/article/pii/S0304380025003801 Abstract In the absence of sightings, stranding records can be used to parameterize habitat models for marine mammal conservation. However, their reliability for identifying suitable habitat remains uncertain. We assessed how stranding data influence the habitat predictions for American manatee (Trichechus manatus) in the Potiguar Basin, Brazil. Using MaxEnt, we compared models built using: (1) sightings and telemetry data, (2) stranding records alone, and (3) all three data sources combined. We found that the first model based solely on sightings and telemetry produced the most accurate and ecologically meaningful predictions. In contrast, the stranding-only model overestimated suitable habitat by more than threefold, while the combined model overpredicted it by more than twofold. These differences between model predictions are best explained by carcass drift and detection biases and indicate that stranding locations do not reliably reflect areas of actual habitat use. This quantitative assessment provides new insights into the significant biases stranding data can introduce into habitat suitability models. Our findings also highlight the need to prioritize direct observations, and to apply drift modeling and validation against direct observations when using stranding data, to ensure accurate and actionable conservation planning. Enjoy the reading, Carol.

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ISM Manatee Management Job Opportunity
by Pasawicz, Michelle 12 Nov '25

12 Nov '25

Greetings everyone, The Florida Fish and Wildlife Conservation Commission (FWC) Imperiled Species Management Section is seeking an OPS Fisheries and Wildlife Biological Scientist III to aid the section's Manatee Management Program. The Manatee Rules Biologist is responsible for assisting rule development, map development, and permit issuance for Manatee Protection Zones. This position will aid in data management, interpretation of data, and report writing. If you're passionate about wildlife and data-driven conservation, this position offers a unique chance to make a real impact. Please follow this link to the job posting to learn more about this opportunity: https://jobs.myflorida.com/job/TALLAHASSEE-OPS-Fish-&-Wildlife-Biological-S… Sincerely, Michelle R. Pasawicz Manatee Management Program Coordinator Imperiled Species Management Section Florida Fish and Wildlife Conservation Commission<https://myfwc.com/wildlifehabitats/wildlife/manatee/> 620 South Meridian Street - 6A Tallahassee, FL 32399-1600 (850) 922-4330 Michelle.Pasawicz(a)MyFWC.com<mailto:Michelle.Pasawicz@MyFWC.com>

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Call for Papers – Innovative Approaches to Addressing Human Impacts on Marine Mammals
by simone antichi 12 Nov '25

12 Nov '25

Dear colleagues, I am pleased to announce the Research Topic "Innovative Approaches to Addressing Human Impacts on Marine Mammals <https://www.frontiersin.org/research-topics/75174/innovative-approaches-to-…>" in Frontiers in Mammal Science. We invite submissions that apply innovative monitoring tools to detect human impacts on marine mammals, as well as studies that develop, test, or evaluate the effectiveness of mitigation measures. *Manuscript Summary Submission* *Deadline*: 1 February 2026 *Manuscript Submission Deadline*: 22 May 2026 *Guest Editors*: Simone Antichi PhD (Syracuse University, USA) Lorena Viloria-Gómora PhD (Universidad Autónoma de Baja California Sur, Mexico) For more information or questions, please contact me at santichi(a)syr.edu We look forward to receiving your contributions! Best regards, Simone Antichi Postdoctoral Researcher Department of Biology, Syracuse University, USA

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New Paper: Repeated narwhal interactions with moorings (Podolskiy et al.)
by Evgeniy Podolskiy 12 Nov '25

12 Nov '25

Dear colleagues, Our new paper, "Repeated narwhal interactions with moorings challenge safety assumptions of passive acoustic monitoring in the Arctic," has just been published and is available in Open Access here: https://www.nature.com/articles/s42003-025-09106-4 [Abstract] Passive-acoustic monitoring is known as a non-intrusive and transformative tool for ecology and has been increasingly used for conservation and biodiversity monitoring. This study, however, identifies a high level of curiosity in narwhals (Monodon monoceros) with respect to scientific moorings and partially explains recent cases of narwhal entanglements. Using acoustic data from different locations and years together with stomach content analysis, it is shown that foraging narwhals engaged in repeated hits on seafloor moorings (11 times per day), presumably out of curiosity or due to confusion with food items. It is a behavior previously unknown for odontocetes. These results imply that oceanographic monitoring might alter the behavior of whales and poses a risk to their well-being, which should be investigated and accounted for in design. Our findings reveal the intrusive nature of a key scientific method, with implications for the management and conservation of vulnerable marine mammals. Best regards, Evgeny Podolskiy, Assoc. Prof. Arctic Research Center, Hokkaido University, Japan

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New publication: Vessel traffic disrupts walrus vocal behavior in a proposed marine protected area
by Veronica Coppolaro 12 Nov '25

12 Nov '25

Dear colleagues, My co-authors and I are happy to share with you our study of walrus vocal reactions to vessel traffic in a proposed marine protected area in Nunavut, Canada. Our results indicate that ship traffic disrupted walrus vocal behavior and that belugas might show motorboat avoidance. Coppolaro, V. L., Ausen, E. L., Loseto, L., & Marcoux, M. (2025). Vessel traffic disrupts walrus vocal behavior in a proposed marine protected area. Frontiers in Marine Science, 12, 1658328 https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.… Abstract Vessel traffic and underwater noise pollution are increasing in the Arctic. Marine mammals are sensitive to underwater noise from vessels which can negatively impact them at the individual and population levels. The marine region of Southampton Island, Nunavut, Canada, is a recognized key area for many marine mammal species and is under consideration to become a marine protected area. Given the increase in vessel traffic in the region, this study explores the potential impact of vessel traffic noise on the vocal behavior of walruses and belugas. This represents the first study to investigate walrus vocal behavior during exposure to vessels. Underwater acoustic data were collected near Southampton Island from June to November 2018. Vessel movements were tracked using the Automatic Identification System (AIS) data and compared with underwater recordings to identify noise sources by vessel type (ship or motorboat). Generalized linear mixed models were used to assess changes in walrus vocalization rates before, during, and after vessel encounters across vessel type. The results showed that walrus vocalization rates decreased during and after vessel encounters and were significantly lower in the presence of ships than motorboats. Belugas were never recorded during motorboat transits, which may indicate avoidance behavior. However, there was not enough data to investigate this hypothesis further. Our findings demonstrate that vessel traffic influences walrus vocal behavior and highlight the need for updated maritime navigation mitigation measures in the study area. Happy reading, Veronica L.M. Coppolaro ____________________________________________________ Veronica L.M. Coppolaro [cid:67250c42-98c5-4b70-8cd2-0bb0bf81a2a6] ___________________________________________ Our working hours may not be the same. Please don’t feel the need to respond outside of your working schedule. | Nos horaires de travail ne sont pas forcément les mêmes. Ne vous sentez pas obligé de répondre en dehors de vos heures de travail. | I nostri orari lavorativi potrebbero essere diversi. Non sentitevi obbligati a rispondere fuori dal vostro orario di lavoro.

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