October 2020 - MARMAM - devlists.uvic.ca

Recent paper on harbor seal foraging in the Salish Sea
by Madelyn Voelker 04 Oct '20

04 Oct '20

Greetings MARMAM! A recently published paper on harbor seal foraging in the Salish Sea is now available at this link: https://onlinelibrary.wiley.com/doi/epdf/10.1002/ece3.6638. Voelker, MR, Schwarz, D, Thomas, A, Nelson, BW, Acevedo Gutierrez, A. Large‐scale molecular barcoding of prey DNA reveals predictors of intrapopulation feeding diversity in a marine predator. *Ecol Evol*. 2020; 00: 1– 19. https://doi.org/10.1002/ece3.6638 Abstract: Predator–prey interactions are critical in understanding how communities function. However, we need to describe intraspecific variation in diet to accurately depict those interactions. Harbor seals (*Phoca vitulina*) are an abundant marine predator that prey on species of conservation concern. We estimated intrapopulation feeding diversity (variation in feeding habits between individuals of the same species) of harbor seals in the Salish Sea. Estimates of feeding diversity were examined relative to sex, month, and location using a novel approach that combined molecular techniques, repeated cross‐sectional sampling of scat, and a specialization metric (within‐individual consistency in diet measured by the Proportional Similarity Index ([image: urn:x-wiley:20457758:media:ece36638:ece36638-math-0001])). Based on 1,083 scat samples collected from five haul‐out sites during four nonsequential years, we quantified diet using metabarcoding techniques and determined the sex of the scat depositor using a molecular assay. Results suggest that intrapopulation feeding diversity was present. Specialization was high over short periods (24–48 hr, [image: urn:x-wiley:20457758:media:ece36638:ece36638-math-0002] = 0.392, 95% CI = 0.013, R = 100,000) and variable in time and space. Females showed more specialization than males, particularly during summer and fall. Additionally, demersal and benthic prey species were correlated with more specialized diets. The latter finding suggests that this type of prey likely requires specific foraging strategies and that there are trade‐offs between pelagic and benthic foraging styles for harbor seals. This differential feeding on prey species, as well as between sexes of harbor seals, indicates that predator–prey interactions in harbor seals are complex and that each sex may have a different impact on species of conservation concern. As such, describing intrapopulation feeding diversity may unravel hitherto unknown complex predator–prey interactions in the community. Please feel free to contact me with any questions regarding this work. Sincerely, Madelyn Voelker

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new publication: Long-term population and distribution dynamics of an endangered Irrawaddy dolphin population in Balikpapan Bay, Indonesia in response to coastal development (Kreb et al.)
by Danielle Kreb 04 Oct '20

04 Oct '20

Dear MARMAM Colleagues, We are pleased to announce the following paper published in Frontiers in Marine Science, section Marine Conservation and Sustainability: Title; Long-term population and distribution dynamics of an endangered Irrawaddy dolphin population in Balikpapan Bay, Indonesia in response to coastal development Authors: Danielle Kreb, Stanislav Lhota, Lindsay Porter, Alexandra Redman, Imelda Susanti, Milan Lazecky Citation: Kreb D, Lhota S, Porter L, Redman A, Susanti I and Lazecky M (2020) Long-Term Population and Distribution Dynamics of an Endangered Irrawaddy Dolphin Population in Balikpapan Bay, Indonesia in Response to Coastal Development. Front. Mar. Sci. 7: 533197.doi:10.3389/fmars.2020.533197. Summary: Worldwide, cetaceans are impacted by human activities, and those populations that occur in shallow-nearshore habitats are particularly vulnerable. We present the results of the ﬁrst long-term study on the responses of a coastal population of endangered Irrawaddy dolphins to widespread habitat changes. We particularly investigated their responses in terms of distribution and abundance. Boat-based, line-transect surveys were conducted during 12 discrete survey periods in 7 survey years spanning a 15-year period (totaling 78 days and 4,630 km of effort) in Balikpapan Bay, East Kalimantan, Indonesia. Irrawaddy dolphins were sighted on 136 occasions. Through DISTANCE analysis, a decrease in population density in the inner Bay area was observed from 0.45 dolphins/km in 2000–2001 (CV = 24%) to 0.34 and 0.32 dolphins/km in 2008 and 2015 (CV = 31% and 25%). A shift in distribution was noted between the periods 2000– 2002 and 2008–2015 with signiﬁcantly lower occurrence in the lower Bay segment compared to upper Bay segments. No sightings were made in the outer Bay area in later years, which coincided with increased shipping trafﬁc in these areas. A peak in stranding events in 2016 and 2018 followed extremely high phenol levels within Bay waters in 2015 and a large-scale oil spill in 2018. The mean annual mortality rates of 0.67 Irrawaddy dolphins/year is unsustainable based on the lower potential biological removal (PBR) values for best abundance estimates of 2015 (N distance = 45 and N = 73). Other threats to local dolphins include unsustainable ﬁshing, underwater noise caused by construction, particularly piling activities. The research helped to identify Balikpapan Bay as an Important Marine Mammal Area by the IUCN MMPA Taskforce. Serious concerns remain for the concrete plans to move Indonesia’s capital city to the area north of the Bay, in terms of increased shipping trafﬁc and harbor construction in the upper Bay segments that represent primary dolphin habitat. We recommend that protected areas be assigned for marine mammals and artisanal ﬁsheries and shipping trafﬁc and piling activities be excluded from these areas. We also recommend a legislated requirement of a mitigation protocol compulsory for piling and seismic activities within Indonesia. Keywords: Irrawaddy dolphin, abundance, distribution, photo-identiﬁcation, conservation management, oil spill, Balikpapan Bay, Indonesia To view the online publication or download a PDF (open access), please click here: http://journal.frontiersin.org/article/10.3389/fmars.2020.533197/full?&utm_… Thanks for your attention, KInd regards, -------------------------- Danielle Kreb (Ph.D.) Scientific Program Leader Yayasan Konservasi RASI (Rare Aquatic Species of Indonesia) Honorary Lecturer Laboratory of Hydro-Oceanography, Faculty of Fisheries, Mulawarman University, Samarinda Kalimantan Timur, Indonesia Tel/ fax: + 62.541.4113510 Mobile: 081346489515 E-mail: danielle.kreb1(a)gmail.com; yk.rasi(a)gmail.com http://www.ykrasi.org instagram: yayasan_rasi Facebook group/page: Rare Aquatic Species of Indonesia Member of IUCN/SSC Cetacean Specialist Group *“To the dolphin alone, nature has given that which the best* *philosophers seek: friendship for no advantage. Though it has no* *need of help from any man, it is a genial friend to all and has helped mankind.”* *–Plutarch*

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Sirenews call for articles
by James Powell 02 Oct '20

02 Oct '20

The editors of Sirenews, the IUCN newsletter for the Sirenia Specialist Group, wish to invite authors to submit short articles related to sirenian research and conservation to sirenews(a)sea2shore.org. Material should be submitted in MS Word, less than 500 words in length and may contain photographs, tables and graphs. Recent literature, abstracts, announcements, and news of general interest may also be submitted. Deadline for submission is 31 October 2020. James Powell, PhD Anmari Alvarez-Aleman, PhD Editors

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IMMS Winter/Spring Dolphin Photo-ID Research Internship
by Jessica Post 01 Oct '20

01 Oct '20

The Institute for Marine Mammal Studies (IMMS) Research Internship Program is designed as a way for students interested in a career in marine science to gain valuable research experience in a real-world setting. As an intern, you will be trained in all aspects of dolphin photo-ID research as well as any other current research projects at IMMS that may involve species such as: bottlenose dolphins, sea turtles, or diamondback terrapins. Interns will also participate in other operations at IMMS including: stranding response, aquarist and reptile care, and animal care. Our goal is to give interns a well-rounded experience in a variety of areas while providing expert training and experience in marine science research. Interns must: - Commit to a minimum of 12 weeks. The internship can be extended depending on work performance - Be available to work Mon-Fri and must be available for all boat-based surveys. Some field days may fall on the weekends. - Have a strong sense of responsibility, work ethic, attention to detail, and ability to admit mistakes. - Produce high quality research efforts and exhibit strong interpersonal skills Principle Duties include: data entry, learning all research protocols, cropping and sorting photo-ID fin images, learning to use photo-ID programs such as Darwin (fin matching software) and FinBase (Microsoft Access), boat based field research (21' boat), and learn how to use ArcGIS Secondary Duties include: assisting animal care staff, attending marine mammal necropsies, responding to marine mammal and sea turtle strandings, and assisting educational staff Field Days: Interns must be able to spend many hours on the water and on shore in sometimes extreme seasonal conditions. Seasonal temperatures range from over 100 °F in summer to 30 °F in winter. Field days typically exceed eight hours and occur at least two or three times a week Eligibility Requirements Applicants must be 18 or older and must have a genuine interest in marine research. Applicants should be actively pursuing a college degree or be a recent graduate in oceanography, marine science/biology, biology, or a related field. Previous research experience in any capacity is a plus. Applicants must be able and willing to fulfill all duties outlined for this internship program. This is an unpaid position and interns are responsible for their own housing and transportation. Once accepted, IMMS staff will assist interns in finding rooms available to rent, usually with other staff members. The deadline to apply for the Winter/Spring sessions (January 4-March 26, 2021 or March 1-May 21, 2021) is November 1, 2020. For application and full details on how to apply please visit our website at http://imms.org/internship/

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