July 2023 - MARMAM - devlists.uvic.ca

[New paper] Escape response of Guiana dolphins to bottlenose dolphin playback (Julia Cavalli Pierry)
by Julia Cavalli Pierry 06 Jul '23

06 Jul '23

Dear MARMAM community On behalf of my co-authors, I am pleased to share our manuscrit titled "Escape response of Guiana dolphins to bottlenose dolphin playback". Links to access and download the paper:- https://authors.elsevier.com/a/1hMwz51aUnOi0- https://doi.org/10.1016/j.jembe.2023.151925 AbstractAn individual reaction to natural threats, such as the presence of predators or aggressors, can shape the social behaviour of an entire population. In southern Brazil, two coastal Delphinid species, Guiana dolphin (Sotalia guianensis) and Lahille's bottlenose dolphin (Tursiops truncatus gephyreus) co-occur on a regional scale. However, within Baía Norte, there is a clear spatial segregation between these dolphins at a fine-scale that, combined with records of bottlenose dolphins displaying agonistic behaviours towards Guiana dolphins, raised the hypothesis that such aggressive behaviours may contribute to shape this segregated distribution. Here, to investigate this hypothesis, we carried out a controlled exposure experiment in which surface behavioural responses of Guiana dolphins were evaluated before, during and after acoustic playbacks of bottlenose dolphins. Through aerial footages, collected with an unmanned aerial vehicle, we accessed significant behavioural responses of Guiana dolphins in terms of group organization and behavioural states. During playbacks, we observed a decrease in the cohesion index between individual Guiana dolphins and an increase in group synchrony, indicating that individuals coordinate their movements to aggregate when exposed to playback. In addition, time spent in foraging behaviours decreased significantly during playbacks, suggesting that foraging activities are interrupted, and individuals start to travel. These results demonstrate that Guiana dolphins perform a collective escape behaviour when facing bottlenose dolphins, a potential aggressor, reinforcing the hypothesis that such defensive behaviour is mediating the spatial segregation between these dolphins' populations. We hope you enjoy the reading. Please feel free to contact me to request a PDF version or for any question or comment regarding our work at: juliapierry(a)yahoo.com.br Best wishes. Julia Cavalli Pierry PhD Student Universidade Federal do Paraná, Brasil.

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Eulogy for Dr. Roger Payne
by Reynolds, Joel 06 Jul '23

06 Jul '23

Dear MARMAM Community - Linked here for posting (and attached) is my July 5, 2023 remembrance of the great scientist, colleague, and friend Dr. Roger Payne: https://www.nrdc.org/bio/joel-reynolds/remembering-roger-payne-maestro-seas With thanks and best regards, JOEL REYNOLDS Western Director Senior Attorney NATURAL RESOURCES DEFENSE COUNCIL 1314 SECOND STREET SANTA MONICA, CA 90401 T 310.434.2300 F 310.434.2399 JREYNOLDS(a)NRDC.ORG<mailto:jreynolds@nrdc.org> NRDC.ORG<http://www.nrdc.org/> Please save paper. Think before printing.

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New paper on energy expenditure in southern right whales
by Fredrik Christiansen 05 Jul '23

05 Jul '23

Dear colleagues, My co-authors and I are happy to announce the publication of the following paper in the Journal of Experimental Biology: Christiansen, F., Sprogis, K.R., Nielsen, M.L.K., Glarou, M. & Bejder, L. 2023. Energy expenditure of southern right whales varies with body size, reproductive state and activity level. Journal of Experimental Biology 226: jeb245137. doi: 10.1242/jeb.245137. Abstract: Quantifying the energy expenditure of animals is critical to understanding the cost of anthropogenic disturbance relative to their overall energy requirements. We used novel drone focal follows (776 follows, 185 individuals) and aerial photogrammetry (5372 measurements, 791 individuals) to measure the respiration rate and body condition loss of southern right whales (Eubalaena australis) on a breeding ground in Australia. Respiration rates were converted to oxygen consumption rate and field metabolic rate (FMR) using published bioenergetic models. The intra-seasonal loss in body condition of different reproductive classes (calves, juveniles, adults, pregnant and lactating females) was converted to blubber energy loss and total energy expenditure (TEE). Using these two metrics, we tested the effects of body size, reproductive state and activity level on right whale energy expenditure. Respiration rates and mass-specific FMR decreased exponentially with an increase in body size, as expected based on allometric scaling. FMR increased curvilinearly with an increase in swim speed, probably as a result of increased drag and increased locomotion costs. Respiration rates and FMR were 44% higher for pregnant and lactating females compared with those of adults, suggesting significant costs of fetal maintenance and milk production, respectively. The estimated FMR of adults based on their respiration rates corresponded well with the estimated TEE based on body condition loss. The rate of decline in body condition of pregnant and lactating females was considerably higher than expected based on respiration rates, which probably reflects the milk energy transfer from mothers to calves, which is not reflected in their FMR. The paper can be accessed from the following link: https://journals.biologists.com/jeb/article-abstract/226/13/jeb245137/32268… Also, check out the pedunculate oak tree that was planted by JEB for this article: https://forest.biologists.com/landscape/?id=84372 What a great initiative! Best regards, Fredrik Christiansen Senior Researcher Marine Mammal Research, Department of Ecoscience, Aarhus University Frederiksborgvej 399, 4000 Roskilde, Denmark f.christiansen(a)ecos.au.dk<mailto:f.christiansen@ecos.au.dk> http://scholar.google.com.au/citations?user=vkA5Y3EAAAAJ&hl=en&oi=sra http://www.researchgate.net/profile/Fredrik_Christiansen3/?ev=hdr_xprf

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Research volunteer project
by inma rivas 01 Jul '23

01 Jul '23

Dear MARMAM members, I am pleased to announce an exciting research opportunity in the study of cetacean population dynamics in the Alboran Sea, Strait of Gibraltar, and Gulf of Cadiz as part of CIRCE's research programs. We are seeking highly motivated and enthusiastic students to join our team and participate in this thrilling project. Project Description: Research Topic: Study of cetacean population dynamics in the Alboran Sea, Strait of Gibraltar, and Gulf of Cadiz. Species of Interest: Pilot whales, orcas, common bottlenose dolphins, and sperm whales. Project Objectives: Investigate and understand the distribution, abundance, migration, and behavior of these species in the mentioned region. Location: At CIRCE's facilities (Conservation, Information, and Research on Cetaceans, circe.info). Duration: The program has already begun and will run until December 2023. Priority will be given to students who can commit to a longer duration. Stays of less than 3 weeks will not be considered. Students will be incorporated as applications are received, up to a total of 4 students in total. Methodology: Use of cetacean sighting techniques, photo-identification, acoustic recording, data analysis, telemetry tracking, and population modeling. Student Responsibilities: Participate in field research campaigns, collect and analyze data, contribute to individual identification efforts, collaborate in the analysis of behavior and migration patterns, and assist in writing scientific reports. Requirements: Students enrolled in internships or master's degree programs in marine biology, ecology, conservation, or related fields. Previous experience in marine research or fieldwork. Basic knowledge of cetacean sighting techniques, photo-identification, and data analysis. Ability to work in a team and adapt to challenging marine environments. Availability to participate in research campaigns in the Alboran Sea, Strait of Gibraltar, and Gulf of Cadiz during specific periods. We Offer: The opportunity to participate in a high-level research project with a focus on iconic cetacean species. Hands-on experience in the field of marine research and conservation. Collaboration with experts in cetacean studies and the opportunity to contribute to the protection of these species. Possibility to develop skills in cetacean sighting techniques, photo-identification, data analysis, and population modeling. Letters of recommendation and networking opportunities in the field of marine research. The project will cover accommodation expenses, and no fees are required. Participants will be responsible for their own meals. CIRCE provides accommodation at its facilities, which include offices and a 250-square-meter house, as well as access to cooking facilities, etc. Embarkation costs will also be covered by CIRCE. If you are interested in this exciting opportunity and would like to obtain more information, please send an email to [inma(a)circe.info] attaching the following documents: Updated CV. Cover letter stating your interest in the project, relevant experience, and motivations for participation. We appreciate your interest in this research opportunity. If you know anyone who might be interested in this project, we kindly ask you to share this information with them. We look forward to receiving your application and working together on the study of cetacean population dynamics in the Alboran Sea, Strait of Gibraltar, and Gulf of Cadiz! Best regards, Inmaculada Rivas García [Your Name] [Your Title/Affiliation] [Your Email Address] [Your Phone Number]

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