October 2017 - MARMAM - devlists.uvic.ca

River dolphin internships in the Brazilian Amazon
by Tony 08 Oct '19

08 Oct '19

RIVER DOLPHIN RESEARCH INTERNSHIPS IN BRAZIL STARTING SOON Once again, Projeto Boto is recruiting for 9-month internships in the Mamirauá Reserve, Amazon State, Brazil. We require fit, enthusiastic, hard-working fieldworkers who will carry forward our long-term study of botos (Amazon river dolphins). Due to close involvement with local communities, interns are required to have at least moderate Portuguese language skills, or to speak excellent Spanish, in addition to English. There can be no exceptions. In previous years we have received many applications from people who do not fulfil these language criteria, and this is counter-productive. Please only apply if you have the necessary skills. Projeto boto was established in 1994. To date it has hosted more than 60 interns of many different nationalities. The Project's objective is to conserve the boto, and the sympatric tucuxi, through research leading to greater understanding of the biology and ecology of these dolphins. In recent years we have also spent considerable time investigating the impacts of fisheries on these species, and especially a harpoon hunt, in which thousands of botos are killed each year for fish bait. We are seeking two people to commence work as soon as possible, and we would also like to hear from people available in mid-late 2016. Our work is centred on a floating lab/accommodation base, moored in the flooded forest. The research team comprises 3-5 people, who maintain daily observational boat-based research effort year-round. The basis of the work is the piecing together of the lives of over 600 individually recognisable dolphins, to provide publishable information on such diverse topics as growth, reproduction, habitat use, social system, seasonal movements, survival rates, causes of mortality etc. Interns are provided with free accommodation and food, and receive a small monthly stipend (approx $150 US). Transportation to the fieldsite (near the town of Tefé, Amazonas) from Manaus is provided, but interns must arrange and pay for their own transportation to Manaus. They must also have adequate medical insurance. Please do not apply unless you know that you can obtain the airfare to reach Manaus. All necessary training is provided on site. Internships offer the opportunity of a lifetime. They reward hard work and dedication with unique experiences and a chance to stand out from the crowd in subsequent applications for higher degrees and employment. Successful applicants will: be aged 21-35 speak at least moderate Portuguese or fluent Spanish, in addition to English be available for 9-12 months have completed a university degree, preferably in zoology or biology preferably have some fieldwork experience, especially in the use of photo-ID Applicants should please provide: Full CV, complete with age, nationality, linguistic skills, educational and fieldwork experience A letter explaining why you are prepared to dedicate 9 months of your life to this study. The names and email addresses of 3 referees who are familiar with you and your work. The date on which you would be available to start work in the Amazon. Send this information by email to both of the Project co-ordinators, Prof. Tony Martin (boto(a)live.co.uk) and Dr Vera da Silva (vmfdasilva(a)gmail.com) Closing date is 24 November 2015. Applications fulfilling the above criteria will be acknowledged within 4 days of the closing date, but there will be no further communication unless the applicant is short-listed. Short-listed applicants will be notified by 30 November latest.

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New publication: From the pool to the sea: Applicable isotope turnover rates and diet to skin discrimination factors for bottlenose dolphins (Tursiops truncatus)
by Joan Giménez Verdugo 01 Mar '19

01 Mar '19

Dear all, We are pleased to announce the publication of the following paper in "Journal of Experimental Marine Biology and Ecology": Giménez, J., Ramírez, F., Almunia, J., Forero, M. G., de Stephanis, R. (2016) From the pool to the sea: Applicable isotope turnover rates and diet to skin discrimination factors for bottlenose dolphins (*Tursiops truncatus*). Journal of Experimental Marine Biology and Ecology 475:54-61. *Abstract:*One of the most common applications in isotopic ecology is the assessment of animal's assimilated diet through mass-balance mixing models. Its applicability relies on the use of accurate diet to tissue discrimination factors and turnover rates, which are known to vary as a function of several factors including taxon or tissue type. To date, few studies have assessed isotopic discrimination factors and turnover rates in cetacean species under controlled conditions. Previous experimental studies focused on blood, a difficult sample to obtain in the wild, or on a more appropriate tissue, the skin, but assessed in short experimental trials without arriving to the isotopic equilibrium. We carried out the longest controlled feeding experiment available (350 days) in bottlenose dolphins (*Tursiops truncatus*) in order to assess discrimination factors and turnover rates in skin. Animals' isotopic composition was first stabilized by maintaining individuals under an isotopically constant diet during 172 days. Afterwards, diet was shifted and maintained during 178 days to calculate isotopic discrimination and turnover rates. Estimates for isotopic discrimination factors were 1.01 ± 0.37‰ (mean ± sd) for *δ*13C and 1.57 ± 0.52‰ for *δ*15N. Half-life turnover rates were estimated to be 24.16 ± 8.19 days for carbon and 47.63 ± 19 days for nitrogen. This is the first time that applicable values are available to assess the diet of free ranging small cetaceans through stable isotope mixing model analysis. You can download the paper in: http://www.sciencedirect.com/science/article/pii/S0022098115300514 or visit my ResearchGate (https://www.researchgate.net/profile/Joan_Gimenez2) Kind Regards, Joan Giménez -- *Joan Giménez Verdugo* *PhD Student* *Severo Ochoa* Estación Biológica de Doñana (EBD-CSIC) Department of Conservation Biology Americo Vespucio Ave, s/n 41092 Sevilla (Spain) www.ebd.csic.es --- Research Gate: Joan Giménez <https://www.researchgate.net/profile/Joan_Gimenez2> Phone: +34 619 176 849 ü Please consider the environment before printing this E-mail

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Volunteer Research Assistants/Interns - Summer 2017 Florida, USA and Bimini, The Bahamas
by Kelly Melillo Sweeting 25 Feb '19

25 Feb '19

Dolphin Communication Project (DCP) - Volunteer Research Assistants/Interns - Summer 2017 Florida, USA and Bimini, The Bahamas The Dolphin Communication Project (DCP, www.dolphincommunicationproject.org) is currently seeking two interns for the summer of 2017. These internships have field and office components, both of which are mandatory, and total 9-12 weeks, depending on DCP's schedule. DCP looks at how dolphins communicate and attempts to shed more light on the meaning of their interactions. With research ongoing since 1991, our questions focus primarily on communication and behavior among dolphins. Interns will spend the field portion of this internship at our Bimini, Bahamas, research site, where we study wild Atlantic spotted and bottlenose dolphins. An abbreviated publication list is available at the end of this post. Responsibilities In the field: --Travel to and assist for approximately 6 weeks at our Bimini research site (exact dates TBD, likely beginning in late, following the office component) --Assist gathering data (general observations, photographs) during 4-6 hour/day boat excursions (weather and schedule dependent) --Complete photo-identification of dolphins from still photography and video as well as other data entry and analysis tasks --Assist with on-board and outreach education as well as web-based projects --Represent DCP in an enthusiastic, responsible, mature and respectful manner At the office: --Travel to and assist for 4-5 weeks at our Port Saint Lucie, Florida (FL) office (exact dates TBD, likely prior to field component, beginning in late May) --Process and analyze data, including, but not limited to: photo-identification of individuals from other DCP research sites, event sampling from video data for behavioral analyses, and acoustic analysis of dolphin sounds --Assist in the development and implementation of education programs for schools and the general public, as needed Requirements Successful interns must have basic computer skills and working knowledge of Microsoft Word, Excel and PowerPoint. Current enrollment in a degree-seeking program, background in science and/or animal behavior and experience on boats and/or with photo-identification are all desired, but not necessarily required. The successful candidates will be comfortable on a boat for several hours at a time in varying conditions, including extreme heat. They will also be proficient swimmers with the desire to improve snorkeling and free-diving skills. They will be able to work as a team both in a small office and in a fairly remote and isolated field setting. Good writing and public speaking skills are a must, as is attention to details. Interns must be at least 18 years of age. Although international applicants are invited to apply, all applicants should know that interns are responsible for their own daily transportation to/from the FL office and public transportation is limited in this area; therefore, all interns should have their own transportation while in FL. Expenses and Compensation This is an unpaid internship. Interns are responsible for their own transportation to Bimini and Florida. There is a $1,100.00 fee that will cover housing in the field (on-island transportation not needed). Room, board and transportation while in Florida are the responsibility of the intern. Although assistance in finding housing may be available, the ability to find suitable housing in Florida is ultimately the interns’ responsibility. We recommend all applicants complete a preliminary housing search in advance of submitting their applications. Interested applicants should review information at this link: http://dolphincommunicationproject.org/index.php/get-involved/internships. Please read this page thoroughly before applying or emailing questions . Send a completed application (downloadable and detailed at the link above) to kelly(a)dcpmail.org. Applications are due 28 February 2017. Due to field schedules, only electronic applications will be accepted. Interviews (via telephone or Skype) will be arranged for selected candidates in early March. For more information, please contact Kelly Melillo Sweeting at kelly(a)dcpmail.org. ----------------------------------------------------------------------------------------------------------------------------- Selected Refereed Publications: (for a full list of publications by DCP researchers, please visit: http://www.dolphincommunicationproject.org/index.php/about-dolphins/scienti…) Dudzinski, K.M., Clark, C.W., Würsig, B. 1995. A mobile video/acoustic system for simultaneously recording dolphin behavior and vocalizations underwater. Aquatic Mammals 21(3): 187-193. Dudzinski, K.M. 1998. Contact behavior and signal exchange among Atlantic spotted dolphins (Stenella frontalis). Aquatic Mammals 24(3): 129-142. Dudzinski, K.M., M. Sakai, M., Masaki, K., Kogi, K., Hishii, T., Kurimoto, M. 2003. Behavioral observations of adult and sub-adult dolphins towards two dead bottlenose dolphins (one female and one male). Aquatic Mammals 29(1): 108-116. Gregg, J.D., Dudzinski, K.M., Smith, H.V. 2007. Do dolphins eavesdrop on the echolocation signals of conspecifics? International Journal of Comparative Psychology, 20: 65-88 Dudzinski, K.M., Thomas, J. Gregg, J.D. 2008. Communication. In (W.F. Perrin, B. Würsig, H.C.M. Thewissen, eds) Encyclopedia of Marine Mammals, second edition. Academic Press, Inc. Melillo, K.E., Dudzinski, K.M., Cornick, L.A. 2009. Interactions between Atlantic spotted (Stenella frontalis) and bottlenose (Tursiops truncatus) dolphins off Bimini, The Bahamas, 2003-2007. Aquatic Mammals, 35:281-291 Dudzinski, K.M., Gregg, J.D., Paulos, R.D., Kuczaj, S.A. 2010. A comparison of pectoral fin contact behaviour for three distinct dolphin populations. Behavioural Processes, 84: 559-567. Greene, W., Melillo-Sweeting, K., Dudzinski, K. 2011. Comparing object play in captive and wild dolphins. International Journal of Comparative Psychology 24(3):292-306. Dudzinski, KM, Gregg, JD, Melillo-Sweeting, K, Levengood, A, Seay, B., Kuczaj II, SA. 2012. Tactile contact exchanges between dolphins: self-rubbing versus inter-individual contact in three species from three geographies. International Journal of Comparative Psychology 25:21-43. Dudzinski, KM, Danaher-Garcia, N, Gregg, JD. 2013. Pectoral fin contact between dolphin dyads at Zoo Duisburg, with comparison to other dolphin study populations. Aquatic Mammals. 39(4): 335-343. Melillo-Sweeting, K, Turnbull, S and Guttridge, T. 2014. Evidence of shark attacks on Atlantic spotted (Stenella frontalis) and bottlenose dolphins (Tursiops truncatus) off Bimini, The Bahamas. Marine Mammal Science. DOI: 10.1111/mms.12082 Melillo-Sweeting, K., Yeater, D., Dudzinski, KM. 2015. Dolphin sightings near the coast of Bimini, The Bahamas, 2003 – 2013. Aquatic Mammals 41.3: 245-251. DOI: 10.1578/AM.41.3.2015.245. _______________________________ Kelly Melillo Sweeting Bimini Research Manager Dolphin Communication Project www.dolphincommunicationproject.org

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JNCC MMO (UK) and BOEM PSO (Gulf of Mexico) Training Courses
by Alison Gill 13 Nov '17

13 Nov '17

Intelligent Ocean Ltd (http://www.intelligentocean.com/) is running the following training courses in January in Kings Lynn, UK for which we have spaces available. Joint Nature Conservation Committee (JNCC) Marine Mammal Observer (MMO) Training for UK - 21st January 2016 - £130 Bureau of Ocean Energy Management (BOEM) Protected Species Observer (PSO) Training for Gulf of Mexico, USA - 22nd January 2016 - £60 (when taken in conjunction with the JNCC MMO course). To book a place please use our online booking system at this link http://www.intelligentocean.com/booking.php Alison Gill Intelligent Ocean Ltd www.intelligentocean.com

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Marine noise budgets in practice
by Nathan Merchant (Cefas) 06 Nov '17

06 Nov '17

Dear Colleagues, We are pleased to announce a paper in Conservation Letters on the management of cumulative underwater noise pollution, one of the major anthropogenic pressures on marine mammals. Includes working example with North Sea harbour porpoise. Now available online as an accepted manuscript (fully formatted version to follow): Merchant, N.D., Faulkner, R.F., Martinez, R. (in press) Marine noise budgets in practice. Conservation Letters. https://doi.org/10.1111/conl.12420 Abstract: Many countries have made statutory commitments to ensure that underwater noise pollution is at levels which do not harm marine ecosystems. Nevertheless, coordinated action to manage cumulative noise levels is lacking, despite broad recognition of the risks to ecosystem health. We attribute this impasse to a lack of quantitative management targets – or ‘noise budgets’ – which regulatory decision-makers can work towards, and propose a framework of risk-based noise exposure indicators which make such targets possible. These indicators employ novel noise exposure curves to quantify the proportion of a population or habitat exposed, and the associated exposure duration. This methodology facilitates both place-based and ecosystem-based approaches, enabling the integration of noise management into marine spatial planning, risk assessment of population-level consequences, and cumulative effects assessment. Using data from the first international assessment of impulsive noise activity, we apply this approach to herring spawning and harbor porpoise in the North Sea. Kind regards, Nathan Dr Nathan Merchant Principal Scientist, Noise & Bioacoustics Team Pakefield Road, Lowestoft, Suffolk, NR33 0HT, UK Tel: +44(0) 1502 527780 | Mob: +44 (0) 7789 651086 Email: nathan.merchant(a)cefas.co.uk<mailto:nathan.merchant@cefas.co.uk> [cid:image002.jpg@01D34CC0.C4665930] https://scholar.google.co.uk/citations?user=XPctSoUAAAAJ&hl=en https://www.cefas.co.uk/services/research-advice-and-consultancy/underwater… https://www.cefas.co.uk/media/52916/noise-bioacoustics.pdf Follow us on: [cid:image001.gif@01D09A11.D21ECDA0]<https://twitter.com/CefasGovUK>[cid:image002.gif@01D09A11.D21ECDA0]<http://www.linkedin.com/company/cefas> ________________________________ This email and any attachments are intended for the named recipient only. Its unauthorised use, distribution, disclosure, storage or copying is not permitted. If you have received it in error, please destroy all copies and notify the sender. In messages of a non-business nature, the views and opinions expressed are the author's own and do not necessarily reflect those of Cefas. Communications on Cefas’ computer systems may be monitored and/or recorded to secure the effective operation of the system and for other lawful purposes.

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New publication on the spatiotemporal distribution of harbour porpoises off Maryland, USA
by Jessica Wingfield 05 Nov '17

05 Nov '17

Hello MARMAM community, My co-authors and I are pleased to announce our recent publication in PLOS ONE: Wingfield JE, O’Brien M, Lyubchich V, Roberts JJ, Halpin PN, Rice AN, et al. (2017) Year-round spatiotemporal distribution of harbour porpoises within and around the Maryland wind energy area. PLoS ONE 12(5): e0176653. Abstract Offshore windfarms provide renewable energy, but activities during the construction phase can affect marine mammals. To understand how the construction of an offshore windfarm in the Maryland Wind Energy Area (WEA) off Maryland, USA, might impact harbour porpoises *(Phocoena phocoena*), it is essential to determine their poorly understood year-round distribution. Although habitat-based models can help predict the occurrence of species in areas with limited or no sampling, they require validation to determine the accuracy of the predictions. Incorporating more than 18 months of harbour porpoise detection data from passive acoustic monitoring, generalized auto-regressive moving average and generalized additive models were used to investigate harbour porpoise occurrence within and around the Maryland WEA in relation to temporal and environmental variables. Acoustic detection metrics were compared to habitat-based density estimates derived from aerial and boat-based sightings to validate the model predictions. Harbour porpoises occurred significantly more frequently during January to May, and foraged significantly more often in the evenings to early mornings at sites within and outside the Maryland WEA. Harbour porpoise occurrence peaked at sea surface temperatures of 5°C and chlorophyll *a* concentrations of 4.5 to 7.4 mg m-3. The acoustic detections were significantly correlated with the predicted densities, except at the most inshore site. This study provides insight into previously unknown fine-scale spatial and temporal patterns in distribution of harbour porpoises offshore of Maryland. The results can be used to help inform future monitoring and mitigate the impacts of windfarm construction and other human activities. The publication can be downloaded from: http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0176653 Thank you, Jessica -- Jessica Wingfield Faculty Research Assistant Chesapeake Biological Laboratory 146 Williams Street Solomons, MD, 20688 Tel: (1) 410-326-7225

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New publication on reproduction in harbour porpoises
by tinakesselring＠aol.de 31 Oct '17

31 Oct '17

Dear Colleagues, we are pleased to announce the recent publication of the following paper in PLOS ONE: Coming of Age: - Do female harbour porpoises (Phocoena phocoena) from the North Sea and Baltic Sea have sufficient time to reproduce in a human influenced environment? By: Kesselring, T., Viquerat, S., Brehm, R. and Siebert, U. PLoS ONE12(10): e0186951. https://doi.org/10.1371/journal.pone.0186951 Abstract: The harbour porpoise is the only cetacean species native to German waters. Since human pressures are suggested to shorten their reproductive lifespan, basic knowledge on reproduction is strongly required. One parameter is the onset of sexual maturity in female harbour porpoises. Therefore, we investigated the first signs of sexual maturity for a period of almost two decades (1990–2016). Ovaries from 111 female harbour porpoises from the German North Sea and Baltic Sea were examined for the presence and morphological structure of follicles, corpora lutea and corpora albicantia. Based on the ovarian characteristics we performed the first model-based estimation of age at sexual maturity for harbour porpoises from German waters. Additionally, we produced a demographical age structure based on all female strandings and bycatches from German coasts. Our results showed thatcorpora lutea and corpora albicantia as signs of former ovulation could be found in individuals at an age of 4.95 (± 0.6) years. No significant differences between specimens from the North Sea and Baltic Sea were detected. However, the average age at death differed significantly with 5.70 (± 0.27) years for North Sea animals and 3.67 (± 0.30) years for those in the Baltic Sea. Growing evidence exists that the shortened lifespan of Baltic Sea harbour porpoises is linked to an anthropogenically influenced environment with rising bycatch mortalities due to local gillnet fisheries. Thus, our findings support the idea of local management plans based on a model-based detection of age at sexual maturity and considering the anthropogenic impacts on the population for effective protection of harbour porpoises and the North Sea and Baltic Sea. For any questions please feel free to contact us. Best wishes, Tina Kesselring and co-authors Tina Kesselring University of Veterinary Medicine Hannover, Foundation Institute for Terrestrial and Aquatic Wildlife Research (ITAW) Institute for Anatomy Werftstr. 6 25761 Büsum Germany +49 511 856-8174 tina.kesselring(a)tiho-hannover.de

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New publication: Right whale demography and forecasting
by Erin Meyer-Gutbrod 31 Oct '17

31 Oct '17

Dear MARMAM subscribers, We are pleased to announce the publication of the following paper in Global Change Biology: Meyer-Gutbrod EL, Greene CH. Uncertain recovery of the North Atlantic right whale in a changing ocean. Glob Change Biol. 2017;00:1–10. https:// doi.org/10.1111/gcb.13929 Abstract: Human activities have placed populations of many endangered species at risk and mitigation efforts typically focus on reducing anthropogenic sources of mortality. However, failing to recognize the additional role of environmental factors in regulating birth and mortality rates can lead to erroneous demographic analyses and conclusions. The North Atlantic right whale population is currently the focus of conservation efforts aimed at reducing mortality rates associated with ship strikes and entanglement in fishing gear. Consistent monitoring of the population since 1980 has revealed evidence that climate-associated changes in prey availability have played an important role in the population’s recovery. The considerable interdecadal differences observed in population growth coincide with remote Arctic and North Atlantic oceanographic processes that link to the Gulf of Maine ecosystem. Here, we build capture-recapture models to quantify the role of prey availability on right whale demographic transitional probabilities and use a corresponding demographic model to project population growth rates into the next century. Contrary to previous predictions, the right whale population is projected to recover in the future as long as prey availability and mortality rates remain within the ranges observed during 1980–2012. However, recent events indicate a northward range shift in right whale prey, potentially resulting in decreased prey availability and/or an expansion of right whale habitat into unprotected waters. An annual increase in the number of whale deaths comparable to that observed during the summer 2017 mass mortality event may cause a decline to extinction even under conditions of normal prey availability. This study highlights the importance of understanding the oceanographic context for observed population changes when evaluating the efficacy of conservation management plans for endangered marine species. Cheers, Erin Meyer-Gutbrod -- Erin Meyer-Gutbrod, Ph.D. http://meyer-gutbrod.weebly.com/ Marine Science Institute; Rm 3405 University of California, Santa Barbara Santa Barbara, CA 93106-6150 eringutbrod(a)gmail.com 216-548-9082

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Mote Marine Laboratory, Manatee Research Program Internship
by Christina 30 Oct '17

30 Oct '17

Mote Marine Laboratory Manatee Research Program Internships Program Description The Manatee Research Program studies several aspects of the biology of manatees inhabiting the waters of southwestern Florida, including population dynamics, population genetics, habitat use, distributional patterns and social behavior. Winter field data and samples are collected using photo-identification and non-invasive genetic sampling with some habitat sampling. Field work during the winter season is conducted primarily in Charlotte Harbor and the Ft. Myers area and is both land and boat based. The long-term database of the program contributes to management and conservation measurements for Florida manatees. Additionally, the program collaborates with manatee researchers throughout the state of Florida and the Caribbean. For more information about, please visit:https://mote.org/research/program/manatee-research. WE ARE CURRENTLY SEEKING INTERNS TO BEGIN IN JANUARY 2018, WITH APPLICATIONS DUE BY NOVEMBER 27th Internship Description Internships are available during all four seasons and must be a MINIMUM of 12 weeks. Hours are typically Monday-Friday, 8:30am-5pm, although some longer days may be required for field work (especially during the winter season). Interns should expect to spend about 20% of their time in the field and about 80% of their time in the office/lab. Field work duties include assisting with data collection (which consists of photographing manatees, as well as recording behavioral observations and environmental conditions), boat handling, and equipment use and maintenance. Field work requires spending long hours in the field, sometimes in uncomfortable weather conditions. Office/Lab duties include data entry and database maintenance, image downloading and processing, matching images to known animals, creating representative sketches from images for searching, equipment maintenance, as well as miscellaneous tasks and errands. There is no financial compensation for these internship positions, and successful applicants will be responsible for their own living and transportation expenses. Shared housing opportunities near Mote Marine Laboratory may be available. A few scholarships may be available from Mote Marine Laboratory through a competitive application process (US citizens only). Required Qualifications Minimum of 18 years of age and engaged in or recently completed undergraduate studies A background or degree in Biology, Marine Biology, Ecology, Zoology, or a related field is preferred Basic computer proficiency in Microsoft Office (especially Excel and Access); previous experience using ArcMap GIS is a plus but not required Excellent communication skills; fluent in English Must be physically able to stand for long periods of time and lift heavy objects Knowledge of photography/SLR camera use and/or drawing skills are a plus Desire and willingness to acquire knowledge and skills related to marine mammal field work and capable of working well as a team To apply for a Manatee Research Program internship: Fill out an application form at Mote Marine Laboratory’s website (https://mote.org/research/internships/college-internship-program-overview) and be sure to select “Manatee Research Program” as your first choice Complete and provide to Mote’s intern office all other application materials including: a statement of interest, current college transcript, letter of recommendation, andcurriculum vitae (incomplete applications will not be considered) Applicants may contact the Manatee Research Program’s intern coordinator, Christina Nau, (cnau(a)mote.org) with questions regarding the internship. -- Christina Nau Manatee Research Program Mote Marine Laboratory 1600 Ken Thompson Parkway Sarasota FL 34236 Phone: (941) 388-4441 ext. 471 cnau(a)mote.org

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New publication on reproduction in harbour porpoises
by Kesselring, Tina 30 Oct '17

30 Oct '17

Dear Colleagues, we are pleased to announce the recent publication of the following paper in PLOS ONE: Coming of Age: - Do female harbour porpoises (Phocoena phocoena) from the North Sea and Baltic Sea have sufficient time to reproduce in a human influenced environment? By: Kesselring, T., Viquerat, S., Brehm, R. and Siebert, U. PLoS ONE12(10): e0186951. https://doi.org/10.1371/journal.pone.0186951 Abstract: The harbour porpoise is the only cetacean species native to German waters. Since human pressures are suggested to shorten their reproductive lifespan, basic knowledge on reproduction is strongly required. One parameter is the onset of sexual maturity in female harbour porpoises. Therefore, we investigated the first signs of sexual maturity for a period of almost two decades (1990–2016). Ovaries from 111 female harbour porpoises from the German North Sea and Baltic Sea were examined for the presence and morphological structure of follicles, corpora lutea and corpora albicantia. Based on the ovarian characteristics we performed the first model-based estimation of age at sexual maturity for harbour porpoises from German waters. Additionally, we produced a demographical age structure based on all female strandings and bycatches from German coasts. Our results showed that corpora lutea and corpora albicantia as signs of former ovulation could be found in individuals at an age of 4.95 (± 0.6) years. No significant differences between specimens from the North Sea and Baltic Sea were detected. However, the average age at death differed significantly with 5.70 (± 0.27) years for North Sea animals and 3.67 (± 0.30) years for those in the Baltic Sea. Growing evidence exists that the shortened lifespan of Baltic Sea harbour porpoises is linked to an anthropogenically influenced environment with rising bycatch mortalities due to local gillnet fisheries. Thus, our findings support the idea of local management plans based on a model-based detection of age at sexual maturity and considering the anthropogenic impacts on the population for effective protection of harbour porpoises and the North Sea and Baltic Sea. For any questions please feel free to contact us. Best wishes, Tina Kesselring and co-authors Tina Kesselring University of Veterinary Medicine Hannover, Foundation Institute for Terrestrial and Aquatic Wildlife Research (ITAW) Institute for Anatomy Werftstr. 6 25761 Büsum Germany +49 511 856-8174 Fax. +49 511 856-8181

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