September 2022 - MARMAM - devlists.uvic.ca

Short Note: South American sea lion twins
by Renan Lima 17 Sep '22

17 Sep '22

Dear MARMAM community, On behalf of my coauthors, I'm happy to share our new research note reporting a rare case of twinning in South American sea lions: Lima RC, Cebuhar J, Martí L, Franco-Trecu V, Oliveira L, Botta S (2022) FIRST RECORD OF TWIN FETUSES OF SOUTH AMERICAN SEA LION ON THE SOUTHERN BRAZILIAN COAST. Oecologia Australis, vol. 26, no 3, https://doi.org/10.4257/oeco.2022.2603.09 Abstract: We report the first known occurrence of South American sea lion (Otaria flavescens) twins on the South American coast. In January 2021 a female pregnant with dizygotic male and female fetuses was found dead in southern Brazil. The timing of the stranding event suggests that the pregnancy was near-term. However, the total body length and weight of fetuses suggested poor development and growth, which could be due to the advanced age of the mother and/or poor nutrition of the individual during pregnancy. The female fetus was larger and heavier than the male and could have been implanted and developed earlier. The note is open access and is available on the following link: https://revistas.ufrj.br/index.php/oa/article/view/45742 Best regards, Renan Lima --- *Renan Costa de Lima, MSc* Doutorando do Programa de Pós-Graduação em Oceanografia Biológica Laboratório de Ecologia e Conservação da Megafauna Marinha - EcoMega Instituto de Oceanografia Universidade Federal do Rio Grande (FURG) COMNAP Antarctic Fellow 2021 Fone: +55(53)99718994 | e-mail: renancdl(a)gmail.com www.researchgate.net/profile/Renan-Lima-2

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New publication: Evidence of Type A-like killer whale predating on marine mammals in Atacama Desert Coast
by Ana M Garcia Cegarra 17 Sep '22

17 Sep '22

Dear marmam community, I am pleased to announce my recent publication in Aquatic Mammals. García-Cegarra, A.M. 2022. Evidence of Type A-like killer whales (*Orcinus orca*) predating on marine mammals along the Atacama Desert coast, Chile. *Aquatic Mammals * 2, 48(5), 436-448, DOI 10.1578/AM.48.5.2022.436 *Abstract * Killer whales (*Orcinus orca*) are marine apex predators distributed across the world’s oceans. In the last 40 years, researchers have increasingly differentiated killer whales into ecotypes based on genetics, morphology, behaviour, acoustic repertoire, habitat, and trophic ecology. While killer whale ecotypes in the Northern Hemisphere are well studied, the recognition of distinct killer whale forms in the Southern Hemisphere is mainly limited to Antarctic waters. Although present in less studied regions, such as along the Atacama Desert coast in the Southeast Pacific Ocean, limited information is available regarding their biology or trophic ecology. Herein, multiple lines of evidence are presented for killer whale predation on marine mammals in northern Chile. Using information from systematic boat-based surveys, whale-watching tour surveys, and reports from fishermen/citizen scientists, 19 killer whale sightings are reported along the coast of northern Chile (from the Arica and Parinacota region in the north to the Atacama region in the south). Killer whales were photo-identified as corresponding to the Southern Hemisphere Type A-like ecotype according to their dorsal fin shape and white eye patch. One killer whale pod, which included two males, one female, one juvenile, and one calf, was resighted six times from 2016 to 2021 in northern Chile and was observed hunting South American sea lions (*Otaria flavescens*), dusky dolphins (*Lagenorhynchus obscurus*), and long-beaked common dolphins (*Delphinus cf. capensis*). Killer whales were observed taking advantage of large aggregations of sea lions associated with the offshore purse-seine fishery. Adult killer whales used the hulls of fishing vessels to prevent sea lions from escaping. Photo-identification analysis of a fin whale (*Balaenoptera physalus*) catalogue from Mejillones Peninsula showed that 2.6% of all identified whales had apparent rake marks from killer whale teeth on their dorsal fins. These data show that Type A-like killer whales in northern Chile prey on several species of marine mammals. Please do not hesitate to contact me if you want a pdf copy ( albatracu(a)gmail.com) All the best Ana *Ana M. García-Cegarra, Ph.D.*

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New publication: Seasonal distribution of an opportunistic apex predator (Tursiops truncatus) in marine coastal habitats of the Western Mediterranean Sea
by Daniela Silvia Pace 15 Sep '22

15 Sep '22

Dear MARMAM community, on behalf of my coauthors, I'm pleased to announce the recent publication of our paper in Frontiers in Marine Science: Pace DS, Panunzi G, Arcangeli A, Moro S, Jona-Lasinio G and Martino S (2022). Seasonal distribution of an opportunistic apex predator (Tursiops truncatus) in marine coastal habitats of the Western Mediterranean Sea. Front. Mar. Sci. 9:939692. https://www.frontiersin.org/articles/10.3389/fmars.2022.939692/full Abstract Assessing the distribution of marine apex–predators is pivotal to understanding community interactions and defining management goals. However, several challenges arise in both estimates and predictions considering the distinctive and mutable biological/ecological requirements of these species and the influence of human activities. Thus, efforts to study apex–predators’ spatial distribution patterns must deal with inherent uncertainty. Relying on different data sources (research programs and social media reports), physiographic and environmental covariates (depth, slope, surface temperature and chlorophyll–a), and specific source–related detection functions, this study selected a Spatial Log–Gaussian Cox Process to model the distribution patterns of an opportunistic apex–predator, the common bottlenose dolphin (Tursiops truncatus), over 14 years (2008−2021) in the Mediterranean Sea (Italy) using a total of 955 encounters. Both depth and slope showed a significant (95% significance) reduction effect in the encounters when deeper and steeper, respectively. Temperature (parabolic) shows a positive effect (90% significance), while chlorophyll–a values did not seem to have a significant effect on encounter intensities within each season. The estimated posterior mean and the coefficient of variation surfaces for the intensity by season showed higher intensity in summer near the Tiber River estuary than other regions. Almost homogeneous predictions were observed in winter, with marginal greater intensities where lower temperatures and higher chlorophyll–a concentration were observed. The relatively low variance was predicted in the more coastal parts of the study area within each season, while higher uncertainty was instead revealed in the southernmost offshore area. This study highlighted the persistent presence of the common bottlenose dolphin in the investigated area both winter and summer, with a coherent distribution within each season, and rare transient occurrences in deeper waters (where uncertainty increases). Thanks to its versatile characteristics, the species seems to well adapt to different seasonal conditions and maintain its distributional range. With very best wishes, Daniela -- Daniela Silvia Pace, PhD Department of Environmental Biology Marine Ecology Lab Sapienza University of Rome Viale dell’Università 32 00185 Rome, Italy mail: danielasilvia.pace(a)uniroma1.it mobile: +39 346 1039652 office: +39 06 4991 4763 skype: lagenorinco Orcid ID: https://orcid.org/0000-0001-5121-7080 [image: Risultati immagini per logo sapienza] "*Ecology is a contingent science under the broad control of climate and evolutionary change. It is an essential science if we are to achieve conservation successes. There is much left to do*" (Charles J. Krebs) -- **Fai crescere le giovani ricercatrici e i giovani ricercatori* **con il 5 per mille alla Sapienza *Scrivi il codice fiscale dell'Università *80209930587 Cinque per mille <https://www.uniroma1.it/it/node/23149>*

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PhD opportunity
by JEANNIARD DU DOT Tiphaine 15 Sep '22

15 Sep '22

PhD studentship opportunity - Marine Ecology Title: Increasing our understanding of climate change impacts on a keystone species in the Arctic: the hooded seal Project description: Over recent decades, the Arctic has experienced a warming three times faster than the global average, resulting in major changes in ice and oceanographic conditions. These structural changes impact organisms at every level of the Arctic food web from phytoplankton to top predators. Ice seals are considered bio-indicators of the Artic ecosystem health, yet little is known about how ice seals have responded both horizontally and vertically to seasonal and annual changes in the Arctic ecosystem in the past. As the Arctic continues to lose ice, this study will examine future consequences of these ecosystem changes on ice seals. Successful candidates will combine biologging-derived behavioural and movement data, environmental data and simulation modelling to 1) characterize the foraging behaviours of hooded seals using tri-dimensional movement data, their relation to foraging efficiency, and to their habitat characteristics; 2) assess changes in foraging efficiencies through time-series data and their links to population trajectory; 3) build models that predict the future vertical distribution of the Arctic hooded seal. This research will allow us to infer mechanistic links between the ice seals foraging ecology and their physical environment, and better understand the impacts of environmental changes on ice seal individuals and populations from forecasts of climate induced habitat shifts. Qualifications: We seek candidates with an MSc in Marine Ecology, Biology or Ocean Sciences. Rigorous candidate with creative and collaborative spirit that will help foster a collegial culture that is grounded in equity, diversity and inclusiveness. She/He must be highly autonomous and able to adapt quickly to different lab/team/country settings as this PhD is co-supervised between French and Canadian institutions. Proficiency in English is mandatory. The candidate is expected to complete his PhD in 36mo (France requirements). Research abilities: * Programming (proficient in R and/or matlab) * Advanced statistical modelling * Biologging data analysis * Oceanographic data analysis * Scientific writing and communication Location: The candidate will be registered at La Rochelle University in France but will be co-supervised between Dr Tiphaine Jeanniard du Dot from Centre d'Etudes Biologiques de Chize at La Rochelle University and Dr Ruth Joy from School of Environmental Science at Simon Fraser University in Canada. The candidate will be expected to start their degree in France but to spend time in both institutions/countries in the course of their degree. Start date: March 2023 To apply: Please send CV with references, Statement of Research Interest (1 page) and unofficial copy of transcripts to Dr Tiphaine Jeanniard du Dot tiphaine.jeanniard-du-dot(a)cebc.cnrs.fr<mailto:tiphaine.jeanniard-du-dot@cebc.cnrs.fr> and Dr Ruth Joy r.joy(a)sfu.ca<mailto:r.joy@sfu.ca> or contact us for more information. Application deadline: Oct 15th 2022.

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Job Opportunity: Biometrician
by Lori Polasek 14 Sep '22

14 Sep '22

*The Alaska Department of Fish and Game, Division of Wildlife Conservation is recruiting for a Biometrician 1/2/3 located in either Juneau, Anchorage or Fairbanks !* *What you will be doing:* The department reposting the search for an individual with an interest in marine mammal research and conservation with vision to be part of an innovative and skilled research team, and who aspires to solve scientific problems and address conservation issues. This position provides biometric assistance to mid and upper level wildlife biologists (Wildlife Biologist II, III, and IV) to support the statewide Marine Mammal Program staff and projects and consultations on management level issues. This position works closely on statewide research issues and offers a rare opportunity to provide biometric support to a diverse array of marine mammal projects in beautiful and remote areas of Alaska. The wildlife species associated with these projects include such species as ice seals, polar bears, sea lions, belugas, walrus, otters, and bowhead whales, as well as other marine mammal species. The successful applicant may also have the opportunity to participate in wildlife field work. *To view the full posting please visit: ADFG_Biometrician <ADFG_Biometrician>*

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MARINE ANIMAL REHABILITATION & ENVIRONMENTAL EDUCATION INTERNSHIP
by Gabbie Nicoletta 14 Sep '22

14 Sep '22

MARINE ANIMAL REHABILITATION & ENVIRONMENTAL EDUCATION INTERNSHIP The National Marine Life Center (NMLC) is now accepting applications for the Marine Animal Rehabilitation and Environmental Education Internship for a bridging internship session, running from the first week of November 2022 through the first week of March 2023. The application deadline is October 1, 2022. Animal Care Responsibilities: Depending on need, case load, and time of year, interns may assist with the care of the NMLC rehabilitation patients including seals, sea turtles, and a variety of native turtle species. Animal Care duties may include animal restraint; cleaning; disinfecting tanks, equipment, and environmental enrichment devices; diet preparation; administering feeds (including tube feeding); record keeping; facility maintenance; and water quality testing. Interns may also assist animal care staff with medical procedures, admission exams, animal necropsies, and release events. Education Responsibilities: Interns may assist with environmental education programs, including on-site programs, off-site programs, fairs, and festivals. Programs will focus on marine animals, rehabilitation practices, conservation, and STEM activities. Interns may learn how to effectively interpret and educate guests of NMLC on marine animals and conservation. Interns may be asked to work in the gift shop and assist with various office projects such as fundraising and data entry. There may be opportunities to create different educational materials needed that are aligned with the Massachusetts State Frameworks and Ocean Literacy Principles. Please note that the summer internship session offers the most opportunity for education experience. Fall and Spring sessions offer less opportunity given the time of year, so the focus may shift to operations or administrative tasks. Other Responsibilities: Each intern is assigned to multiple projects in different areas of the organization, e.g. research, fundraising, rehabilitation, marketing, social media or education. A weekly chore will be delegated to each intern to assist with the upkeep of the facility and equipment. Each intern is required to attend regularly scheduled meetings throughout their time at NMLC. At the end of the internship, the intern will deliver a presentation about their experience and projects to staff and volunteers. Positions are unpaid. Interns must have their own transportation. Housing is not provided, but NMLC will offer suggestions. Qualifications * Must be currently enrolled in, or recently graduated from an accredited college or university; preference will be given to students or recent graduates working towards biology, environmental studies, marine science, education, or other related fields. * Must demonstrate strong written and verbal communication skills. * Must be adaptable, responsible, hardworking, willing to learn, and have attention to detail. * Must be able to work independently and as part of a team. * Must be willing to engage in a positive and informative manner with members of the public on a regular basis. * Must be willing to participate in and receive constructive feedback. * Must expect to work approximately 40 hours per week, which can include early morning and/or late-night seal feedings depending on the season. * Interns may be required to work some holidays. * Interns may be required to participate in fundraisers held by NMLC, which may occur outside of normally scheduled hours * International applicants are responsible for their own VISA arrangements, etc. * If an intern plans to receive school credit for an internship they must notify staff prior to the internship start date, and it will be the responsibility of the applicant to ensure all required paperwork is completed and submitted. Physical Requirements: * Must be able to endure some physical exertion, such as long periods of standing; recurring bending, crouching, stooping, stretching, reaching, or similar activities; recurring lifting of moderately heavy items such as medical equipment and boxes of medical supplies. * The work may require specific but common physical characteristics and abilities such as lifting up to 50 pounds, above-average agility, and dexterity. To Apply: Send your resume, cover letter, and one letter of recommendation to internship(a)nmlc.org<mailto:internship@nmlc.org> or P.O. Box 269, Buzzards Bay, Massachusetts 02532. Due to the high number of applications, only qualified candidates will be contacted. Gabriella Nicoletta Animal Care, Necropsy, & Operations Coordinator National Marine Life Center P.O. Box 269, 120 Main Street Buzzards Bay, MA 02532-0269 Office: (508)-743-9888 Cell: (585)-775-5354 Email: gnicoletta(a)nmlc.org www.nmlc.org

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Atlantic spotted and bottlenose dolphin sympatric use of nearshore water at Bimini, The Bahamas
by Kathleen Dudzinski 14 Sep '22

14 Sep '22

To our Colleagues, We are pleased to announce the publication of our most recent paper detailing the sympatric distribution of Atlantic spotted and common bottlenose dolphins in the nearshore water around Bimini, The Bahamas. Levengood, A, Melillo-Sweeting, K, Ribic, CA, Beck, AJ, Dudzinski, KM (2022) Shoreline distribution of dolphins along North Bimini Island, The Bahamas. Caribbean Journal of Science, 52(2), 162-176. https://doi.org/10.18475/cjos.v52i2.a3 <https://doi.org/10.18475/cjos.v52i2.a3> Abstract—Within nearshore waters off Bimini, The Bahamas, Atlantic spotted (Stenella frontalis) and common bottlenose (Tursiops truncatus) dolphins are sympatric but separated spatially in different geographic areas and water depth ranges. Afternoon surveys during summer months across a 16-year period showed S. frontalis used the northern part of the nearshore area more, while T. truncatus used the southern area more. Generally, examination of geographic zones and water depth distributions of both species before and after construction of a pier in the study area suggested these dolphins were not impacted, long-term, by this anthropogenic activity. Still some differences in use of the nearshore area were identified. For water depth, S. frontalis varied use between 5–<12 m and 12–<20 m, depending on location along the coast. In contrast, T. truncatus consistently used the 5–<12 m depths. This difference may be related to how each species used the nearshore area, with T. truncatus feeding more and S. frontalis travelling and doing other activities. A small change in the distribution of S. frontalis by water depth off the northern coast of Bimini was found, specifically an increased use of deeper (12–20 m) water post 2014, which is unlikely an effect of pier construction as S. frontalis continued to use the 5–12 m depths as they had before pier construction. How this change might be related to an unprecedented 2013 S. frontalis immigration event, which might have disrupted the social structure, habitat/resource use, and distribution of both species, is discussed. The publication is available as pdf and html text: https://bioone.org/journals/caribbean-journal-of-science/volume-52/issue-2/… <https://bioone.org/journals/caribbean-journal-of-science/volume-52/issue-2/…> Please let us know if you have questions. Thank you. Cheers, Kathleen (on behalf of my co-authors: Alexis Levengood, Kel Mellilo-Sweeting, Christine Ribic and AJ Beck) Kathleen M. Dudzinski, Ph.D. Director, Dolphin Communication Project kathleen(a)dcpmail.org www.dolphincommunicationproject.org

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New publication: Assessment of social mixing and spatial overlap as a pathway for disease transmission in a northeast Florida estuarine dolphin community
by Kristy Brightwell 14 Sep '22

14 Sep '22

Hello, My coauthors and I are pleased to share our new publication. Our article “Assessment of social mixing and spatial overlap as a pathway for disease transmission in a northeast Florida estuarine dolphin community” has been published in Mammalian Biology as a contribution to the special issue on “Individual Identification and Photographic Techniques in Mammalian Ecological and Behavioural Research – Part 2: Field Studies and Applications” — Editors: Leszek Karczmarski, Stephen C.Y. Chan, Scott Y.S. Chui, and Elissa Z. Cameron. Szott, E.A., Brightwell, K. & Gibson, Q. Assessment of social mixing and spatial overlap as a pathway for disease transmission in a northeast Florida estuarine dolphin community. *Mamm Biol* (2022). https://doi.org/10.1007/s42991-022-00282-y Abstract Common bottlenose dolphins (Tursiops truncatus) in estuarine systems are often subjected to natural and anthropogenic risks, which may impact their health and behaviors. Effective management for this species should incorporate continual, updated information on behavioral patterns of the individuals within populations. Currently, the Jacksonville Estuarine System stock assessment report, which includes dolphins in the St. Johns River (SJR) in northeast Florida, is based on data from the 1990s. Since then, dolphins’ use of the SJR has shifted, and the community has been impacted by two unusual mortality events (UME). This study analyzed site fidelity, space use and overlap, and social mixing with respect to the epizootic 2013–2015 UME, whose infectious agent was cetacean morbillivirus (CeMV). Examination of residency status determined that most dolphins sighted in the river were year-round residents (x̄=45%, SD = 3.20). Space use and overlap of core areas occurred among residency categories but varied between cold and warm seasons and across time periods. There were key, highly connected individuals in the social network, which may have influenced disease transmission during the UME. Individuals infected by CeMV that stranded during the UME shared overlapping core areas with each other and with individuals from different residency categories. Altogether, this information on site fidelity, spatial overlap, and social mixing will help improve management plans for SJR dolphins, lead to better response efforts to future unusual mortality events, and increase the understanding of disease transmission in social species. You can access a view-only version of the article using the following link: https://rdcu.be/cVeFR Please contact the corresponding author, Emily Szott (es.unf.3(a)gmail.com) with any questions. Best, Kristy Brightwell UNF Dolphin Research Program

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Aquatic Mammals issue 48.5 available online
by Kathleen Dudzinski 14 Sep '22

14 Sep '22

Dear MARMAM and ECS Talk Subscriber, Happy September! The 5th issue of volume 48 (48.5) of Aquatic Mammals journal is now published online. Further information about the journal can be found at: http://www.aquaticmammalsjournal.org/ <http://www.aquaticmammalsjournal.org/> To submit a manuscript for publication consideration, please visit: http://am.expressacademic.org/actions/author.php <http://am.expressacademic.org/actions/author.php> With regards, Kathleen M. Dudzinski, Ph.D. Editor, Aquatic Mammals Journal business(a)aquaticmammalsjournal.org <mailto:business@aquaticmammalsjournal.org> Volume 48, Issue 5 (Items preceded by an ** are open access) Noppakarn Singkhum, Patharapol Piamsomboon, Nitiwadee Keschumras, Thitiorn Ussavarangsi, Sirawich Srisiri, Junpen Suwimonteerabutr, Nantarika Chansue, and Thanida Haetrakul. (2022). Semen Quality and Electron Microscopy of Captive Irrawaddy Dolphin (Orcaella brevirostris) Sperm. Aquatic Mammals, 48(5), 395-400. DOI: https://doi.org/10.1578/AM.48.5.2022.395 <https://doi.org/10.1578/AM.48.5.2022.395> Meghan E. Rickard, Kate S. Lomac-MacNair, Darren S. Ireland, Sarah M. Leiter, Mitchell D. Poster, and Ann M. Zoidis. (2022). Evidence of Large Whale Socio-Sexual Behavior in the New York Bight. Aquatic Mammals, 48(5), 401-417. DOI: https://doi.org/10.1578/AM.48.5.2022.401 <https://doi.org/10.1578/AM.48.5.2022.401> Juan José Alava, Marjorie Riofrío-Lazo, Gabriel Reygondeau, Patricia Rosero, Isabel C. Avila, Daniel Lara, Fernando Gil, Carlos F. Yaipen-Llanos, Fernando R. Elorriaga-Verplancken, and Diego Páez-Rosas. (2022). Southern Elephant Seals (Mirounga leonina) in the Galapagos Islands and the Eastern Tropical Pacific Amid Ocean Environmental Changes: Towards a Habitat Suitability Index. Aquatic Mammals, 48(5), 418-431. DOI: https://doi.org/10.1578/AM.48.5.2022.418 <https://doi.org/10.1578/AM.48.5.2022.418> Robin W. Baird, Jesse James, Chad Mata, and Marc Hughes. (2022). Two Gray Whale (Eschrichtius robustus) Sightings off Hawaiʻi Island: The First Records for the Central Tropical Pacific. Aquatic Mammals, 48(5), 432-435. DOI: https://doi.org/10.1578/AM.48.5.2022.432 <https://doi.org/10.1578/AM.48.5.2022.432> Ana M. García-Cegarra. (2022). Evidence of Type A-Like Killer Whales (Orcinus orca) Predating on Marine Mammals Along the Atacama Desert Coast, Chile. Aquatic Mammals, 48(5), 436-448. DOI: https://doi.org/10.1578/AM.48.5.2022.436 <https://doi.org/10.1578/AM.48.5.2022.436> **Tiu Similä, Tore Haug, Lotta Lindblom, Christina Lockyer, and Seán A. O’Callaghan. (2022). Stomach Contents of Three Sperm Whales (Physeter macrocephalus) Stranded on Andøya, Northern Norway. Aquatic Mammals, 48(5), 449-455. DOI: https://doi.org/10.1578/AM.48.5.2022.449 <https://doi.org/10.1578/AM.48.5.2022.449> Jure Miočić-Stošić, Maša Frleta-Valić, and Draško Holcer. (2022). The Camera Does Not Lie: Superimposed Dorsal Fins Introducing Error in Cetacean Photo-Identification. Aquatic Mammals, 48(5), 456-461. DOI: https://doi.org/10.1578/AM.48.5.2022.456 <https://doi.org/10.1578/AM.48.5.2022.456> Jared R. Towers and Paul Tixier. (2022). Indian Ocean Sighting of Shepherd’s Beaked Whale (Tasmacetus shepherdi) Helps Confirm Circumpolar Distribution in Southern Hemisphere.Aquatic Mammals, 48(5), 462-467. DOI: https://doi.org/10.1578/AM.48.5.2022.462 <https://doi.org/10.1578/AM.48.5.2022.462> **Jason N. Bruck and Elizabeth Henderson. (2022). In Memoriam: Sam Ridgway (1936 to 2022). Aquatic Mammals, 48(5), 468-471. DOI: https://doi.org/10.1578/AM.48.5.2022.468 <https://doi.org/10.1578/AM.48.5.2022.468>

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New paper: Seasonal and diel patterns in singing activitiy of humpback whales in Bermuda
by Denise Risch 14 Sep '22

14 Sep '22

Dear All, on behalf of Tamara Narganes Homfeldt and all the co-authors I would like to let you know about our recently published paper in Frontiers of Marine Science (Research Topic: Managing Deep-sea and Open Ocean Ecosystems at Ocean Basin Scale - Volume <https://www.frontiersin.org/research-topics/26134#articles>): Narganes Homfeldt, Tamara; Risch, Denise; Stevenson, Andrew and Henry, Lea-Anne *"Seasonal and diel patterns in singing activity of humpback whales migrating through Bermuda"* Abstract Humpback whales (Megaptera novaeangliae) produce song and non-song vocalisations, which allows their presence to be detected through passive acoustic monitoring. To determine the seasonal and diel acoustic presence and acoustic behaviour of humpback whales at the migratory stopover site off Bermuda, three hydrophones were deployed between March 2018 and April 2019 on Challenger Bank and the Bermuda platform. Song was the predominant vocalisation type encountered, with 65% of song recordings containing whale chorus and a clear seasonal trend of humpback whale occurrence in the spring and winter months from late December to mid-May. A strong diel pattern in singing activity was detected. Singing activity significantly increased at night relative to the daytime (p<0.01), whilst twilight periods were characterised by intermediate levels of singing. The song structure encountered in spring 2018 consisted of 18 units, 6 themes and 5 transitional phrases. The high occurrence of whale chorus and the strong seasonal and diel patterns of male humpback whale singing activity highlights the importance of Bermuda not just on their northward migration during spring, as described historically, but also on their southward migration during winter. Bermuda therefore constitutes a two-way migratory stopover site for humpback whales. The present study also provides Bermuda’s planning authorities with better constraints on the duration and intensity of anthropogenic activities in these waters. The article is open access and can be downloaded following the link below: https://doi.org/10.3389/fmars.2022.941793 For further information please contact the first or last authors: tamaranarganes(a)web.de; l.henry(a)ed.ac.uk All the best, Denise

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