September 2020 - MARMAM - devlists.uvic.ca

Request to fill out a short survey (8 mins) for a study about potential cetacean collision risk with tourist vessels
by Dalia Carolina Barragán Barrera 10 Sep '20

10 Sep '20

Greeting MARMAM, please consider this email, not the one I sent before. Thanks! Greeting MARMAM, As researchers of Colombian Maritime Directorate, currently we are conducting a study to evaluate potential collision risk for five cetacean species with touristic vessels. We really appreciate your support as marine mammals specialists to complete a short survey (8 mins) and send me by *September 20*. Please find attached the survey as an excel file and its instructions in pdf. Let us clarify that we request your opinion as specialists based on your experience working with marine mammals anywhere, not specifically in Colombia. Please feel free to share this survey among your colleagues. We greatly appreciate your time and collaboration in our work. Thanks in advance, All the best, Dalia *Dalia C. Barragán Barrera* Marine Biologist, Universidad de Bogotá Jorge Tadeo Lozano PhD Biological Sciences, Universidad de los Andes Researcher, Fundación Macuáticos Colombia <http://www.macuaticos.org/> Researcher, R&E Ocean Community Conservation Foundation <https://www.oceancommunityconservation.org/> General Editor, Revista Digital *Fulica* <https://www.revistadigitalfulica.com/>, @rdfulica CvLAC Colombia <http://scienti.colciencias.gov.co:8081/cvlac/visualizador/generarCurriculoC…> | ResearchGate <https://www.researchgate.net/profile/Dalia_Barragan-Barrera> | LinkedIn <https://www.linkedin.com/in/daliacbarraganbarrera/?originalSubdomain=co> ORCiD <https://orcid.org/0000-0003-4023-9908> | SCOPUS <https://www.scopus.com/authid/detail.uri?authorId=57193270664> | Google Scholar <https://scholar.google.com/citations?user=1rNoJ0EAAAAJ&hl=en>

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New paper: Drivers and consequences of polar bear diet in the Canadian Beaufort Sea
by Katie Florko 10 Sep '20

10 Sep '20

Dear MARMAM, My co-authors and I are pleased to announce the publication of our paper in Oecologia: Florko, K.R.N, Thiemann, G.W., Bromaghin, J.F. Drivers and consequences of an apex predator diet composition in the Canadian Beaufort Sea. *Oecologia*, doi: 10.1007/s00442-020-04747-0 https://link.springer.com/article/10.1007/s00442-020-04747-0 Abstract: Polar bears (*Ursus maritimus*) rely on annual sea ice as their primary habitat for hunting marine mammal prey. Given their long lifespan, wide geographic distribution, and position at the top of the Arctic marine food web, the diet composition of polar bears can provide insights into temporal and spatial ecosystem dynamics related to climate-mediated sea ice loss. Polar bears with the greatest ecological constraints on diet composition may be most vulnerable to climate-related changes in ice conditions and prey availability. We used quantitative fatty acid signature analysis (QFASA) to estimate the diets of polar bears (*n *= 419) in two western Canadian Arctic subpopulations (Northern Beaufort Sea and Southern Beaufort Sea) from 1999 to 2015. Polar bear diets were dominated by ringed seal (*Pusa hispida*), with interannual, seasonal, age- and sex-specific variation. Foraging area and sea ice conditions also affected polar bear diet composition. Most variation in bear diet was explained by longitude, reflecting spatial variation in prey availability. Sea ice conditions (extent, thickness, and seasonal duration) declined throughout the study period, and date of sea ice break-up in the preceding spring was positively correlated with female body condition and consumption of beluga whale (*Delphinapterus leucas*), suggesting that bears foraged on beluga whales during entrapment events. Female body condition was positively correlated with ringed seal consumption, and negatively correlated with bearded seal consumption. This study provides insights into the complex relationships between declining sea ice habitat and the diet composition and foraging success of a wide-ranging apex predator. Keywords: Foraging ecology, Fatty acids, Sea ice, Climate change, Polar bear Best regards, Katie Florko -- Katie R.N. Florko, PhD Candidate Statistical Ecology Research Group Institute for the Oceans and Fisheries University of British Columbia Twitter: @kflorko Email: katieflorko(a)gmail.com

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New publication: The diel pattern in harbour porpoise clicking behaviour is not a response to prey activity
by Anna Osiecka 10 Sep '20

10 Sep '20

Dear colleagues, Me and my co-authors are happy to share our newest work on diel clicking patterns in the harbour porpoise: Osiecka, A.N., Jones, O. & Wahlberg, M. The diel pattern in harbour porpoise clicking behaviour is not a response to prey activity. *Sci Rep* *10, *14876 (2020). https://doi.org/10.1038/s41598-020-71957-0 *Abstract* Wild harbour porpoises (*Phocoena phocoena*) mainly forage during the night and, because they rely on echolocation to detect their prey, this is also when they are most acoustically active. It has been hypothesised that this activity pattern is a response to the diel behaviour of their major prey species. To test this hypothesis, we monitored the acoustic activity of two captive harbour porpoises held in a net pen continuously during a full year and fed by their human keepers during daylight hours, thus removing the influence of prey activity. The porpoises were exposed to similar temperature and ambient light conditions as free-ranging animals living in the same region. Throughout the year, there was a pronounced diel pattern in acoustic activity of the porpoises, with significantly greater activity at night, and a clear peak around sunrise and sunset throughout the year. Clicking activity was not dependent on lunar illumination or water level. Because the porpoises in the pen are fed and trained during daylight hours, the results indicate that factors other than fish behaviour are strongly influencing the diel clicking behaviour pattern of the species. The article is available open access at: https://www.nature.com/articles/s41598-020-71957-0 Kindest regards, Anna N Osiecka

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New publication: Near real-time marine mammal monitoring from gliders
by Katie Kowarski 08 Sep '20

08 Sep '20

My co-authors and I are pleased to announce our recent publication available online! Kowarski, K. A., Gaudet, B. J., Cole, A. J., Maxner, E. E., Turner, S. P., Martin, S. B., Johnson, H. D., & Moloney, J. E. (2020). Near real-time marine mammal monitoring from gliders: Practical challenges, system development, and management implications. The Journal of the Acoustical Society of America, 148(3), 1215-1230. https://doi.org/10.1121/10.0001811 https://doi.org/10.1121/10.0001811 ABSTRACT: In 2017, an endangered North Atlantic right whale mortality event in the Gulf of St. Lawrence, Canada, triggered the implementation of dynamic mitigation measures that required real-time information on whale distribution. Underwater glider-based acoustic monitoring offers a possible solution for collecting near real-time information but has many practical challenges including self-noise, energy restrictions, and computing capacity, as well as limited glider-to-shore data transfer bandwidth. This paper describes the development of a near real-time baleen whale acoustic monitoring glider system and its evaluation in the Gulf of St. Lawrence in 2018. Development focused on identifying and prioritizing important acoustic events and on sending contextual information to shore for human validation. The system performance was evaluated post-retrieval, then the trial was simulated using optimized parameters. Trial simulation evaluation revealed that the validated detections of right, fin, and blue whales produced by the system were all correct; the proportion of species occurrence missed varied depending on the timeframe considered. Glider-based near real-time monitoring can be an effective and reliable technique to inform dynamic mitigation strategies for species such as the North Atlantic right whale.

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VOLUNTEER SURVEYOR OPPORTUNITY - Southern UK Seas October 2020
by Tom Brereton 07 Sep '20

07 Sep '20

VOLUNTEER SURVEYOR OPPORTUNITY - Southern UK Seas October 2020 Volunteer cetacean and seabird survey opportunity - in the Western English Channel, Celtic and Irish Sea: OCTOBER 2020 In partnership with CEFAS, MARINElife will once again be joining the Peltic survey this autumn from Lowestoft, sailing the Celtic Sea, Irish Sea. Southern North Sea and English Channel. Two places are available. Proposed duration 35 days Start 3rd October from Lowestoft, Suffolk, England Return to Lowestoft An excellent variety of cetacean and seabird species are likely to be encountered on this trip, with the opportunity to join and learn from a multidisciplinary team carrying out pelagic fish and plankton surveys and collecting oceanographic data. It is a great opportunity to contribute to analyses linking mammals and seabird sightings to prey availability. Please let us know if you are an experienced MARINElife surveyor and have availability on these dates. Or are available for the first or second part of the survey, as there may be opportunity to split teams dependent on the level of response. All meals are provided on board the vessel; specific dietary requirements must be specified in your application. Bunks have a bed, en-suite bathroom, TV, desk and internet access. There is also access to the communal areas of the ship. Requirements: * Experienced in cetacean and/or seabird identification at sea. * A valid ENG1 medical certificate (see www.dft.gov.uk/mca/mcga-mgn264.pdf <http://www.dft.gov.uk/mca/mcga-mgn264.pdf> <http://www.dft.gov.uk/mca/mcga-mgn264.pdf> and http://www.dft.gov.uk/mca/mcga07-home/workingatsea/mcga-medicalcertandadvice /mcga-ml5-medicalinfo/mcga-approved-docs-list.htm ) * Personal Sea Survival Certificate (MCA approved Personal Survival Techniques (according to STCW 95 convention). It is really important that you have or obtain the correct PST certificate to be able to join this trip. OR A BOSIET Offshore survival certificate OR STCW10 Sea survival course If you would like to join the research team as a Marine Mammal & Seabird Surveyor, please email tom.brereton(a)marine-life.org.uk <mailto:tom.brereton@marine-life.org.uk> including a CV or brief summary of experience. I look forward to hearing from you. Tom Brereton

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Heart function in cetaceans
by Andreas Fahlman 07 Sep '20

07 Sep '20

Dear MARMAM community, We would like to share our new publication on cardiac function and cardiorespiratory coupling in cetaceans. In this study, the function of the heart was investigated in the bottlenose dolphin, the beluga, the killer whale, the false killer whale, and the pilot whale. The results showed that cetaceans have large variation in heart rate directly after a breath, and when compared with land mammals, the relationship between breathing frequency and heart rate is very different. We propose that these differences may indicate a mechanism that helps improve gas exchange during a surface interval. Fahlman, A., Miedler, S., Marti-Bonmati, L., Ferrero Fernandez, D., Muñoz Caballero, P., Arenarez, J., Rocho-Levine, J., Robeck, T., and Blawas, A.M. (2020). Cardiorespiratory coupling in cetaceans; a physiological strategy to improve gas exchange? Journal of Experimental Biology 223, jeb226365. Video abstract: https://www.youtube.com/watch?v=WxqKniwIVf4 <https://www.youtube.com/watch?v=WxqKniwIVf4> Abstract: In the current study we used transthoracic echocardiography to measure stroke volume (SV), heart rate ( fH) and cardiac output (CO) in adult bottlenose dolphins (Tursiops truncatus), a male beluga whale calf [Delphinapterus leucas, body mass (Mb) range: 151–175 kg] and an adult female false killer whale (Pseudorca crassidens, estimated Mb: 500–550 kg) housed in managed care.Wealso recorded continuous electrocardiogram (ECG) in the beluga whale, bottlenose dolphin, false killer whale, killer whale (Orcinus orca) and pilot whale (Globicephala macrorhynchus) to evaluate cardiorespiratory coupling while breathing spontaneously under voluntary control. The results show that cetaceans have a strong respiratory sinus arrythmia (RSA), during which both fH and SV vary within the interbreath interval, making average values dependent on the breathing frequency ( fR). The RSA-corrected fH was lower for all cetaceans compared with that of similarly sized terrestrial mammals breathing continuously. As compared with terrestrial mammals, the RSA-corrected SV and CO were either lower or the same for the dolphin and false killer whale, while both were elevated in the beluga whale. When plotting fR against fH for an inactive mammal, cetaceans had a greater cardiac response to changes in fR as compared with terrestrial mammals.We propose that these data indicate an important coupling between respiration and cardiac function that enhances gas exchange, and that this RSA is important to maximize gas exchange during surface intervals, similar to that reported in the elephant seal. The journal provides a couple of free downloads that can be found here: https://jeb.biologists.org/content/jexbio/223/17/jeb226365.full.pdf?ijkey=z… <https://jeb.biologists.org/content/jexbio/223/17/jeb226365.full.pdf?ijkey=z…> Or else please send me an email if you would like a pdf copy at: afahlman(a)whoi.edu

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New paper: Blue and fin whale calls off Antarctica
by Fannie Shabangu 05 Sep '20

05 Sep '20

Dear MARMAM Colleagues On behalf of my co-authors, I am delighted to announce the publication of our new paper in Endangered Species Research. Shabangu FW, Andrew RK, Yemane D, Findlay KP. 2020. Acoustic seasonality, behaviour and detection ranges of Antarctic blue and fin whales under different sea ice conditions off Antarctica. Endangered Species Research 43: 21–37. Abstract Descriptions of seasonal occurrence and behaviour of Antarctic blue and fin whales in the Southern Ocean are of pivotal importance for the effective conservation and management of these endangered species. We used an autonomous acoustic recorder to collect bioacoustic data from January through September 2014 to describe the seasonal occurrence, behaviour and detection ranges of Antarctic blue and fin whale calls off the Maud Rise, Antarctica. From 2479 h of recordings, we detected D- and Z-calls plus the 27 Hz chorus of blue whales, the 20 and 99 Hz pulses of fin whales and the 18−28 Hz chorus of blue and fin whales. Blue whale calls were detected throughout the hydrophone deployment period with a peak occurrence in February, indicating continuous presence of whales in a broad Southern Ocean area (given the modelled detection ranges). Fin whale calls were detected from January through July when sea ice was present on the latter dates. No temporal segregation in peaks of diel calling rates of blue and fin whales was observed in autumn, but a clear temporal segregation was apparent in summer. Acoustic propagation models suggest that blue and fin whale calls can be heard as far as 1700 km from the hydrophone position in spring. Random forest models ranked month of the year as the most important predictor of call occurrence and call rates (i.e. behaviour) for these whales. Our work highlights areas around the Maud Rise as important habitats for blue and fin whales in the Southern Ocean. The publication is open-access and available at: https://www.int-res.com/abstracts/esr/v43/p21-37/. Please feel free to contact me if you have questions and/or comments. Best wishes, Fannie _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ Fannie W. Shabangu, PhD Fisheries Management Branch Department of Environment, Forestry and Fisheries Cape Town, South Africa Email: FannieS(a)daff.gov.za; fannie.shabangu(a)yahoo.com Mobile: +27 74 220 0210 Tel: +27 21 402 3553

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New publication:
by Grgur Pleslić 05 Sep '20

05 Sep '20

Dear MARMAM community, My co-authors and I are happy to announce the following publication in Marine Mammal Science: Pleslić G, Rako-Gospić N, Holcer D. Bottlenose dolphins (Tursiops truncatus) in North Dalmatia, Croatia: Occurrence and demographic parameters. Mar Mam Sci. 2020;1–20. https://doi.org/10.1111/mms.12735 The common bottlenose dolphin (*Tursiops truncatus*) population along the eastern Adriatic coast is believed to comprise discrete communities, yet many of them are unstudied. This study provides first description of occurrence and demographic parameters for the community inhabiting waters of North Dalmatia. Dedicated boat-based surveys conducted in summer months from 2013 to 2017 resulted in 13,896 km of research effort and 284 dolphin sightings from which 336 individuals were identified. Site-fidelity analysis revealed that 52.1% of encountered marked adults occur in the area regularly or occasionally. No significant difference among years could be found for mean group sizes (5.73 – 7.46) and group encounter rates (1.159 – 1.942 groups/100 km). Pollock’s Robust Design models estimated annually variable adult apparent survival (0.737 – 0.986) and constant temporary emigration rate of 0.172. The estimated abundance varied annually from 116 to 138 individuals and showed a negative slope, but a significant trend could not be confirmed. Age-dependent models estimated first-year calf survival at 0.875. These results provide a baseline for informed management of two Sites of Community Importance, and a benchmark for future monitoring in North Dalmatian waters, an area under significant anthropogenic pressure. Feel free to contact me with requests for a pdf copy. Best wishes, Grgur Pleslić Science Program Director Blue World Institute of Marine Research and Conservation Kaštel 24, 51551 Veli Lošinj, Croatia www.blue-world.org M: +385 98 976 0271

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new publication
by Errol Ronje 04 Sep '20

04 Sep '20

Please note a new short communication is available: " Intraspecific Aggression Towards Common Bottlenose Dolphin Calves, Northern Gulf of Mexico" The publication is open-access and available at this link: https://aquila.usm.edu/gcr/vol31/iss1/7/ Abstract Infanticide has been widely documented throughout the animal kingdom, and has generally been viewed as an evolved, or adaptive behavior for the perpetrators. Infanticide motivated by increased sexual access to females with calves, or the elimination of potential genetic competition in the form of calf-directed aggression or infanticide, has been proposed for delphinids including killer whales, Indo-Pacific humpback dolphins, Guiana dolphins, and bottlenose dolphins. However, reports of intraspecific aggression towards bottlenose dolphin calves are relatively infrequent, and accounts of confirmed infanticide are rarer still. Reporting instances of intraspecific calf-directed aggression aids researchers to better understand the socio-behavioral context of these aggressive interactions. Here, we report an incident of conspecific aggression towards a calf in a small group of common bottlenose dolphins near Sabine Lake, northwestern Gulf of Mexico. We discuss the behavioral context, and surveyed other researchers to attempt to gauge the prevalence of perceived aggressive interactions among the bottlenose dolphin groups they study in the northern Gulf of Mexico.

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New paper: Imminent Risk of Extirpation for Two Bottlenose Dolphin Communities in the Gulf of Guayaquil, Ecuador
by Fernando Félix Grijalva 04 Sep '20

04 Sep '20

My co-author and I are pleased to inform you about this recently published article in Frontiers on Marine Science. Abstract A long-term study of a common bottlenose dolphin (Tursiops truncatus) population inhabiting the Gulf of Guayaquil, Ecuador (2330 S, 79200W), has been carried out for almost 30 years. Similarly, as in other parts of the world, this population is structured socially and spatially in well-defined subunits or communities. Two of these communities, referred to as Posorja and El Morro, have been studied with major intensity in the last 10 years in the western inner estuary, among others to calculate population parameters that allow assessing their viability in time. Calculated parameters include annual abundance, age and sex composition, annual crude birth rate, calf survival, calf production interval, and average annual mortality/emigration.With these parameters and others derived from other better-studied populations, the trend of both subunits was modeled using the software Vortex. Results show that even under an optimistic scenery both communities will be extinct in the short (Posorja) and mid-term (El Morro), if current stressors continue. Most population parameters calculated in both communities show similar values as in populations elsewhere, but a very low calf survival in Posorja and high mortality/emigration ratios in adults, and probably in juveniles in both communities, contribute to this trend. Population deterioration seems to be the result of different human-induced threats such as fisheries, maritime traffic and others still not well assessed, as well as stochastic demographic events. We recommend taking actions in the short term to halt population decline addressing the major causes of mortality affecting these dolphin communities. The article is free available from the editorial site DOI: 10.3389/fmars.2020.537010. Regards Fernando Félix

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