[MARMAM] new publication: From the sky and on the beaches: complementary tools to evaluate common dolphin bycatch in the Bay of Biscay
Dear colleagues, My co-authors and I are enthusiastic to inform you of the publication of this new paper in open access. It presents an estimate of mortality at sea based on small cetacean carcasses observed during aerial surveys in French Atlantic waters and analysed by Distance Sampling during the winter of 2021. It also explores the complementarity of these results with estimates inferred from strandings collected on beaches using the reverse drift method. Peltier H, Laran S, Dabin W, Daniel P and others (2024) From the sky and on the beaches: complementary tools to evaluate common dolphin bycatch in the Bay of Biscay. Endang Species Res 53:509-522. https://doi.org/10.3354/esr01310 Abstract: Since 1989, multiple stranding events of common dolphins have been regularly recorded along the French Atlantic coast. Examination of the carcasses revealed that most animals presented evidence of bycatch. Using stranding data to infer bycatch levels reveals the highest levels of bycatch to have been recorded since 2016 (4000 to 9000 bycaught individuals). This approach is directly influenced by drift conditions, which can greatly contribute to or hinder our ability to estimate bycatch at sea. In the winter of 2021/2022, the French stranding network recorded an unusually high number of strandings until mid-February and few records in March. Investigation of drift conditions revealed low probability of stranding in March due to constant east-west winds. Reverse drift modelling of carcasses stranded in January and February resulted in an estimate of 3670 (95% CI [2750; 5170]) bycaught common dolphins. Dedicated aerial surveys were conducted in the same area during this period, designed to assess abundance and distribution of marine megafauna in French waters. A high number of carcasses of small Delphininae were observed in March 2021, and the number of carcasses floating at sea could be estimated using conventional distance sampling methodology. In March 2021, mortality at sea was thus estimated at 3250 (95% CI [1288;10198]) common dolphins. The complementary use of both methodologies resulted in an estimate of 6920 (95%CI [4038;15368]) bycaught individuals during winter 2021/2022. This case study highlights that a decrease in strandings does not imply a decrease in mortality at sea. Trends in strandings need to be considered in the light of scientific evidence to avoid delays in decision making. I remain at your disposal for any questions. Best wishes, Helene Peltier -- ~~~ J'ai envoyé ce mail à une heure pratique pour moi. Je n'attends pas de réponse en dehors de vos heures de travail habituelles. I have sent this email at a time that is convenient for me. I do not expect you to respond to it outside of your own usual working hours. ~~~ *Hélène Peltier *- PhD Observatoire PELAGIS – UAR 3462 La Rochelle Université - CNRS Pôle Analytique 5, Allées de l'Océan 17000 La Rochelle, FRANCE St: 05 46 44 99 10 LD: 05 46 50 76 83https://www.observatoire-pelagis.cnrs.fr/ ~~~ "S'il n'y a pas de solution, c'est qu'il n'y a pas de problème" proverbe Shadockien. ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] new publication of common dolphin bycatch in the Bay of Biscay, NE Atlantic
Dear Colleagues, We are glad to share with you our new publication on spatial and temporal co-occurence between mortality areas of common dolphins in the Bay of Biscay (NE Atlantic) and fishing effort. Peltier H, Authier M, Caurant F, Dabin W, Daniel P, Dars C, Demaret F, Meheust E, Van Canneyt O, Spitz J and Ridoux V (2021) In the Wrong Place at the Wrong Time: Identifying Spatiotemporal Co-occurrence of Bycaught Common Dolphins and Fisheries in the Bay of Biscay (NE Atlantic) From 2010 to 2019. /Front. Mar. Sci./ 8:617342. doi: 10.3389/fmars.2021.617342 The paper can be downloaded at: https://www.frontiersin.org/articles/10.3389/fmars.2021.617342/full Please note that a corrigendum is also available: https://www.frontiersin.org/articles/10.3389/fmars.2021.704005/full All the best, Hélène Peltier and co-authors -- Abstract: The first Unusual Mortality Event (UME) related to fishing activity along the Atlantic coast recorded by the French Stranding Network was in 1989: 697 small delphinids, mostly common dolphins, washed ashore, most of them with evidence of having been bycaught. Since then, UMEs of common dolphins have been observed nearly every year in the Bay of Biscay; unprecedented records were broken every year since 2016. The low and unequally distributed observation efforts aboard fishing vessels in the Bay of Biscay, as well as the lack of data on foreign fisheries necessitated the use of complementary data (such as stranding data) to elucidate the involvement of fisheries in dolphin bycatch. The aim of this work was to identify positive spatial and temporal correlations between the likely origins of bycaught stranded common dolphins (estimated from a mechanistic drift model) and fishing effort statistics inferred from Vessel Monitoring System (VMS) data on vessels >12 m long. Fisheries whose effort correlated positively with dolphin mortality areas after 2016 included French midwater trawlers, French Danish seiners, French gillnetters, French trammel netters, Spanish bottom trawlers, and Spanish gillnetters. For the French fleet only, logbook declarations, sales, and surveys carried out by Ifremer were integrated into fishing effort data. Six fleets were active in common dolphin bycatch areas at least twice between 2016 and 2019: gillnetters fishing hake, trammel netters fishing anglerfish, bottom pair trawlers fishing hake, midwater pair trawlers fishing sea bass and hake, and Danish seiners fishing whiting. Except for changes in hake landings in some fisheries, there were no notable changes in total fishing effort practice (gear or target species) based on the data required by the ICES and Council of the European Union that could explain the large increase in stranded common dolphins recorded along the French Atlantic coast after 2016. Small scale or unrecorded changes could have modified interactions between common dolphins and fisheries, but could not be detected through mandatory data-calls. The recent increase in strandings of bycaught common dolphins could have been caused by changes in their distribution and/or ecology, or changes in fishery practices that were undetectable through available data. -- ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] new article on common dolphin -fishery interactions
Dear colleagues, My co-authors and I are pleased to announce you the publication of a new article : / / Peltier, H., Authier, M., Dabin, W., Dars, C., Demaret, F., Doremus, G., Van Canneyt, O., Laran, S., Mendez-Fernandez, P., Spitz, J., Daniel, P., Ridoux, V. /(/2020) /Can modelling the drift of bycaught dolphin stranded carcasses help identify involved fisheries? An exploratory study. /Global Ecology and Conservation. vol. 21. e00843. The aim of this work is to test an approach that could help identify the fisheries potentially involved in a given stranding event. We explored this methodology during the multiple stranding event of common dolphins in winter 2017 along the French Atlantic coasts, related to fishery interactions. Abstract: Between the 1st of February and the March 31, 2017, 793 stranded cetaceans were found along the French Atlantic coasts. Common dolphins made up 84% of these strandings, and most of these presented evidence of death in fishing gear. The aim of this work is to test an approach that could help identify the fisheries potentially involved in a given stranding event. To do this we examined how the distributions of likely areas of mortality of bycaught dolphins, inferred from carcass drift modelling, coincide with fishing effort statistics of various fleets, generated from the Vessel Monitoring System, in the area over the same dates. Using reverse drift modelling, two main mortality areas were identified. A total of 3690 common dolphins (IC95% [2230; 6900]) were estimated to have died in fishing gear within the Bay of Biscay during this unusual stranding event. There was a positive correlation between the origin of stranded bycaught dolphins and the fishing effort distribution of French midwater pair trawlers, Spanish otter bottom trawlers and French Danish seiners. This co-occurrence highlights a risk and identifies fisheries that require further investigation (through observers or e-monitoring). These fisheries differed in their fishing gear, but two characteristics appear to be shared: they targeted predatory fishes (sea bass and hake) in winter and used high vertical opening gear. The paper is freely available online: https://doi.org/10.1016/j.gecco.2019.e00843 We wish you great Christmas holidays! Best wishes On behalf of all co-authors, Helene Peltier -- -- Hélène PELTIER -PhD Observatoire PELAGIS UMS 3462 Université de La Rochelle-CNRS 5, allées de l'océan 17000 La Rochelle, France LD: +33 (0) 5 46 50 76 83 St: +33 (0) 5 46 44 99 10 http://observatoire-pelagis.cnrs.fr/ ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] new publication: ship strikes along French coasts
Dear colleagues, We are pleased to inform you that a new brief research paper on ship strikes of large whales along the French coasts was recently published in Frontiers in Marine Science: *Monitoring of Marine Mammal Strandings Along French Coasts Reveals the Importance of Ship Strikes on Large Cetaceans: A Challenge for the European Marine Strategy Framework Directive* Hélène Peltier <https://www.frontiersin.org/people/u/684060>, Alain Beaufils, Catherine Cesarini, Willy Dabin, Cécile Dars, Fabien Demaret, Frank Dhermain, Ghislain Doremus, Hélène Labach, Olivier Van Canneyt and Jérôme Spitz <https://www.frontiersin.org/people/u/472021> ^Full text available: https://www.frontiersin.org/articles/10.3389/fmars.2019.00486/full Abstract: The incidence of marine traffic has risen in recent decades and is expected to continue rising as maritime traffic, vessel speed, and engine power all continue to increase. Although long considered anecdotal, ship strikes are now recognized as a major threat to cetaceans. However, estimation of ship strike rates is still challenging notably because such events occurred generally far offshore and collision between large ships and whales go often unnoticed by ship crew. The monitoring of marine mammal strandings remain one the most efficient ways to evaluate the problem. In France, a national coordinated network collected data and samples on stranded marine mammals since 1972 along the Mediterranean and Atlantic French coasts. We examined stranding data, including photography and necropsy reports, collected between 1972 and 2017 with the aim to provide a comprehensive review of confirmed collision records of large whales in France. During this period, a total of 51 ship strike incidents were identified which represents the 1st identified causes of mortality for large whale in France. It has increased since 1972 with seven records during the 1st decade to reach 22 stranded animals observed between 2005 and 2017. This issue appears particularly critical in the Mediterranean Sea where one in five stranded whales showed evidence of ship strike. This review of collision records highlights the risk of a negative impact of this anthropogenic pressure on the dynamic of whale populations in Europe, suggesting that ship strike rates could not allow achieving the Good Environmental Status of marine mammal populations required by the European Marine Strategy Framework Directive. Best wishes Helene Peltier -- ------ Hélène PELTIER -PhD Observatoire PELAGIS UMS 3462 Université de La Rochelle-CNRS 5, allées de l'océan 17000 La Rochelle, France LD: +33 (0) 5 46 50 76 83 St: +33 (0) 5 46 44 99 10 http://observatoire-pelagis.cnrs.fr/ ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] new article on stranding interpretation
Dear colleagues, We are glad to inform you that following article was recently published in Environmental Science and Policy. Peltier Ridoux, 2015. MARINE MEGAVERTEBRATES ADRIFT: A FRAMEWORK FOR THE INTERPRETATION OF STRANDING DATA IN PERSPECTIVE OF THE EUROPEAN MARINE STRATEGY FRAMEWORK DIRECTIVE AND OTHER REGIONAL AGREEMENTS. Abstract: For many species of marine megafauna, strandings remain the most important source of biological samples. Because of their opportunistic nature however, strandings data have long been under- or misused in the assessment of population conservation status. Even if many national and international regulations promote the use of strandings in monitoring strategies, the interpretation of strandings remains controversial. The aim of this study is to provide a context for the interpretation of marine megafauna stranding data, in order to assess the achievement of specific objectives against Good Environmental Status criteria in the context of the EU Marine Strategy Framework Directive or other regional agreements. The first step is to construct an a priori spatial distribution under a null hypothesis H0. The a priori spatial distribution of theoretical dead animals can either be set uniformly, consistent with current knowledge on abundance of marine vertebrates, or based on management objectives. The drift prediction of these theoretical carcasses would provide a time series of strandings expected under the null hypothesis. The reverse drift of observed strandings would highlight mortality areas of stranded animals. The correction of these areas by the probability of getting stranded according to drift conditions would provide an estimated distribution of dead animals inferred from strandings. The differences between expected and observed situations constitute anomalies and highlight cases where inferred distribution departs from the a priori spatial distribution. This work proposes several population indicators that can be used anywhere in the world and can be applied for all large marine vertebrates found stranded. The integration of these indicators in MSFD and various regional agreements could provide cost-effective and relevant information on protected species. In the context of impaired ecological situations, the complementary use of several population indicators could strengthen the diagnosis made regarding conservation status and hence conservation strategies. King regards, Helene Peltier Marine megavertebrates adrift: A framework for the interpretation of stranding data in perspective of the European Marine Strategy Framework Directive and other regional agreements -- Helene PELTIER, phD Observatoire PELAGIS, UMS 3462 CNRS/Université La Rochelle 5 allées de l'océan 17000 LA ROCHELLE, FRANCE office: +33 5 16 49 67 82 cell phone: +33 6 82 74 08 41 ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] new article on strandings as indicators of cetacean populations
Dear colleagues, I am glad to inform you that following article was recently published in Ecological Indicators: http://www.sciencedirect.com/science/article/pii/S1470160X13005153 Peltier, H., P. D. Jepson, W. Dabin, R. Deaville, O. Van Canneyt, P. Daniel, and V. Ridoux. (2014). THE CONTRIBUTION OF STRANDING DATA TO MONITORING AND CONSERVATION STRATEGIES FOR CETACEANS: DEVELOPING SPATIALLY EXPLICIT MORTALITY INDICATORS FOR COMMON DOLPHINS (DELPHINUS DELPHIS) IN THE EASTERN NORTH-ATLANTIC. Ecological Indicators, 39, 203-214. Abstract Cetacean strandings are an important source of information on cetacean population status and of biological samples. Nevertheless, collecting stranding data remains opportunistic and their representativity must be improved. The aim of this study was to improve the ecological significance of strandings, through the determination of stranded common dolphin origin found along the coasts of the Channel and the Bay of Biscay, by using the drift prediction model MOTHY. In order to map inferred distribution of dead dolphins, origin of strandings were weighted by the probability that cetaceans dying at sea become stranded. The difference between observed stranding origin and origin of expected strandings under the hypothesis of spatial and temporal uniformity of dead cetaceans, constituted the anomaly in stranding origin. Between 1990 and 2009, 6182 common dolphin strandings were reported by the UK and French stranding networks. Distribution inferred from strandings suggested that common dolphins died mostly in the neritic Bay of Biscay. The anomaly in stranding origin was maximal in the southern Bay of Biscay, highlighted as an area of high relative abundance or strong mortality for common dolphin. The monthly decomposition of this anomaly showed that positive anomaly was located in the southern Bay of Biscay in winter and expanded northward over the whole Bay of Biscay and western Channel in spring and summer. These results were consistent with current knowledge on common dolphin distribution and provide new insight on strandings as cetacean population indicators. These parameters are essential components for assessing the conservation status of vulnerable populations. The pdf is available on request. Please note too that recent article on stranding anomaly of harbor porpoises published in Plos ONE was corrected. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0062180 Best wishes Helene Peltier. -- Hélène PELTIER -PhD Observatoire PELAGIS UMS 3462 Université de La Rochelle-CNRS 5, allées de l'océan 17000 La Rochelle, France hpelt...@univ-lr.fr +33 (0) 16 49 67 82 /+33 (0) 6 82 74 08 41 ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
[MARMAM] new article on strandings as population indicators
Dear colleagues, I am glad to inform you that a new article is now available online: http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0062180 *The Stranding Anomaly as Population Indicator: The Case of Harbour Porpoise /Phocoena phocoena/ in North-Western Europe.* Helene Peltier, Hans J. Baagøe,Kees C. J. Camphuysen,Richard Czeck,Willy Dabin,Pierre Daniel,Rob Deaville,Jan Haelters,Thierry Jauniaux,Lasse F. Jensen,Paul D. Jepson,Guido O. Keijl,Ursula Siebert,Olivier Van Canneyt,Vincent Ridoux * *Abstract: Ecological indicators for monitoring strategies are expected to combine three major characteristics: ecological significance, statistical credibility, and cost-effectiveness. Strategies based on stranding networks rank highly in cost-effectiveness, but their ecological significance and statistical credibility are disputed. Our present goal is to improve the value of stranding data as population indicator as part of monitoring strategies by constructing the spatial and temporal null hypothesis for strandings. The null hypothesis is defined as: small cetacean distribution and mortality are uniform in space and constant in time. We used a drift model to map stranding probabilities and predict stranding patterns of cetacean carcasses under H_0 across the North Sea, the Channel and the Bay of Biscay, for the period 1990--2009. As the most common cetacean occurring in this area, we chose the harbour porpoise /Phocoena phocoena/ for our modelling. The difference between these strandings expected under H_0 and observed strandings is defined as the stranding anomaly. It constituted the stranding data series corrected for drift conditions. Seasonal decomposition of stranding anomaly suggested that drift conditions did not explain observed seasonal variations of porpoise strandings. Long-term stranding anomalies increased first in the southern North Sea, the Channel and Bay of Biscay coasts, and finally the eastern North Sea. The hypothesis of changes in porpoise distribution was consistent with local visual surveys, mostly SCANS surveys (1994 and 2005). This new indicator could be applied to cetacean populations across the world and more widely to marine megafauna. All the best Helene Peltier -- Hélène PELTIER -PhD Observatoire PELAGIS UMS 3462 Université de La Rochelle-CNRS 5, allées de l'océan 17000 La Rochelle, France hpelt...@univ-lr.fr +33 (0) 16 49 67 82 /+33 (0) 6 82 74 08 41 ___ MARMAM mailing list MARMAM@lists.uvic.ca https://lists.uvic.ca/mailman/listinfo/marmam
