28 research outputs found

    Estimating the abundance of the critically endangered Baltic Proper harbour porpoise (Phocoena phocoena) population using passive acoustic monitoring

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    The SAMBAH project was funded by the LIFE+ program of the European Commission (LIFE08 NAT/S/000261) and co-funded by Bundesamt für Naturschutz, Germany (SAMBAH II 5 Vw/52602/2011-Mar 36032/66); Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit, Germany (COSAMM FKZ 0325238); Carlsbergfondet, Denmark (CF16-0861); European Association of Zoos and Aquaria, The Netherlands; Główny Inpektorat Ochrony Środowiska, Poland; Havs-och Vattenmyndigheten, Sweden; Instytut Meteorologii i Gospodarki Wodnej - Państwowy Instytut Badawczy, Poland; Japanese Science and Technology Agency-CREST, Japan (7620-7); Kolmårdens Djurpark, Sweden; Maailman Luonnon Säätiö (WWF) Suomen Rahasto, Finland; Miljøministeriet, Denmark; Miljø- og Fødevareministeriet, Denmark (SN 343/SN-0008); Narodowy Fundusz Ochrony Środowiska i Gospodarki Wodnej, Poland (561/2009/Wn-50/OP/RE-LF/D); Naturvårdsverket, Sweden; SNAK Ph.D. School, Aarhus University, Denmark (91147/365); Tampereen Särkänniemi Ltd., Finland; Turun ammattikorkeakoulu Oy, Finland; Uniwersytet Gdański, Poland; Wojewódzki Fundusz Ochrony Środowiska i Gospodarki Wodnej w Gdańsku, Poland; and Ympäristöministeriö, Finland.Knowing the abundance of a population is a crucial component to assess its conservation status and develop effective conservation plans. For most cetaceans, abundance estimation is difficult given their cryptic and mobile nature, especially when the population is small and has a transnational distribution. In the Baltic Sea, the number of harbour porpoises (Phocoena phocoena) has collapsed since the mid-20th century and the Baltic Proper harbour porpoise is listed as Critically Endangered by the IUCN and HELCOM; however, its abundance remains unknown. Here, one of the largest ever passive acoustic monitoring studies was carried out by eight Baltic Sea nations to estimate the abundance of the Baltic Proper harbour porpoise for the first time. By logging porpoise echolocation signals at 298 stations during May 2011-April 2013, calibrating the loggers' spatial detection performance at sea, and measuring the click rate of tagged individuals, we estimated an abundance of 71-1105 individuals (95% CI, point estimate 491) during May-October within the population's proposed management border. The small abundance estimate strongly supports that the Baltic Proper harbour porpoise is facing an extremely high risk of extinction, and highlights the need for immediate and efficient conservation actions through international cooperation. It also provides a starting point in monitoring the trend of the population abundance to evaluate the effectiveness of management measures and determine its interactions with the larger neighboring Belt Sea population. Further, we offer evidence that design-based passive acoustic monitoring can generate reliable estimates of the abundance of rare and cryptic animal populations across large spatial scales.Publisher PDFPeer reviewe

    Climate change in the Baltic Sea region : a summary

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    Based on the Baltic Earth Assessment Reports of this thematic issue in Earth System Dynamics and recent peer-reviewed literature, current knowledge of the effects of global warming on past and future changes in climate of the Baltic Sea region is summarised and assessed. The study is an update of the Second Assessment of Climate Change (BACC II) published in 2015 and focuses on the atmosphere, land, cryosphere, ocean, sediments, and the terrestrial and marine biosphere. Based on the summaries of the recent knowledge gained in palaeo-, historical, and future regional climate research, we find that the main conclusions from earlier assessments still remain valid. However, new long-term, homogenous observational records, for example, for Scandinavian glacier inventories, sea-level-driven saltwater inflows, so-called Major Baltic Inflows, and phytoplankton species distribution, and new scenario simulations with improved models, for example, for glaciers, lake ice, and marine food web, have become available. In many cases, uncertainties can now be better estimated than before because more models were included in the ensembles, especially for the Baltic Sea. With the help of coupled models, feedbacks between several components of the Earth system have been studied, and multiple driver studies were performed, e.g. projections of the food web that include fisheries, eutrophication, and climate change. New datasets and projections have led to a revised understanding of changes in some variables such as salinity. Furthermore, it has become evident that natural variability, in particular for the ocean on multidecadal timescales, is greater than previously estimated, challenging our ability to detect observed and projected changes in climate. In this context, the first palaeoclimate simulations regionalised for the Baltic Sea region are instructive. Hence, estimated uncertainties for the projections of many variables increased. In addition to the well-known influence of the North Atlantic Oscillation, it was found that also other low-frequency modes of internal variability, such as the Atlantic Multidecadal Variability, have profound effects on the climate of the Baltic Sea region. Challenges were also identified, such as the systematic discrepancy between future cloudiness trends in global and regional models and the difficulty of confidently attributing large observed changes in marine ecosystems to climate change. Finally, we compare our results with other coastal sea assessments, such as the North Sea Region Climate Change Assessment (NOSCCA), and find that the effects of climate change on the Baltic Sea differ from those on the North Sea, since Baltic Sea oceanography and ecosystems are very different from other coastal seas such as the North Sea. While the North Sea dynamics are dominated by tides, the Baltic Sea is characterised by brackish water, a perennial vertical stratification in the southern subbasins, and a seasonal sea ice cover in the northern subbasins.Peer reviewe

    Working Group on Marine Mammal Ecology (WGMME)

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    159 pages.-- This work is licensed under the Creative Commons Attribution 4.0 International License (CC BY 4.0)The Working Group on Marine Mammal Ecology met in 2022 to address five terms of reference. Under the first of these, ToR A, new information on cetacean and seal population abundance, distribution, population/stock structure, was reviewed, including information on vagrant ma-rine mammal species. This was done to ensure the recording of possible range changes in marine mammal species in the future. For cetaceans, an update is given for the different species, providing for a latest estimate for all species studies. In this report, particular attention is given to the updating of information from Canadian and US waters, and together with those countries, latest estimates for cetacean species are provided. For seals, latest monitoring results are given for harbour, grey and Baltic ringed seals. In addition, where possible, local long-term trends are illustrated for those species, based on earlier WGMME efforts to assemble these data into the WGMME seal database. For both spe-cies’ groups, a first account of vagrant species is providedN

    Measurement error using a SeeMaLab structured light 3D scanner against a Microscribe 3D digitizer

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    BACKGROUND: Geometric morphometrics is a powerful approach to capture and quantify morphological shape variation. Both 3D digitizer arms and structured light surface scanners are portable, easy to use, and relatively cheap, which makes these two capturing devices obvious choices for geometric morphometrics. While digitizer arms have been the “gold standard”, benefits of having full 3D models are manifold. We assessed the measurement error and investigate bias associated with the use of an open-source, high-resolution structured light scanner called SeeMaLab against the popular Microscribe 3D digitizer arm. METHODOLOGY: The analyses were based on 22 grey seal (Halichoerus grypus) skulls. 31 fixed anatomical landmarks were annotated both directly using a Microscribe 3D digitizer and on reconstructed 3D digital models created from structured light surface scans. Each skull was scanned twice. Two operators annotated the landmarks, each twice on all the skulls and 3D models, allowing for the investigation of multiple sources of measurement error. We performed multiple Procrustes ANOVAs to compare the two devices in terms of within- and between-operator error, to quantify the measurement error induced by device, to compare between-device error with other sources of variation, and to assess the level of scanning-related error. We investigated the presence of general shape bias due to device and operator. RESULTS: Similar precision was obtained with both devices. If landmarks that were identified as less clearly defined and thus harder to place were omitted, the scanner pipeline would achieve higher precision than the digitizer. Between-operator error was biased and seemed to be smaller when using the scanner pipeline. There were systematic differences between devices, which was mainly driven by landmarks less clearly defined. The factors device, operator and landmark replica were all statistically significant and of similar size, but were minor sources of total shape variation, compared to the biological variation among grey seal skulls. The scanning-related error was small compared to all other error sources. CONCLUSIONS: As the scanner showed precision similar to the digitizer, a scanner should be used if the advantages of obtaining detailed 3D models of a specimen are desired. To obtain high precision, a pre-study should be conducted to identify difficult landmarks. Due to the observed bias, data from different devices and/or operators should not be combined when the expected biological variation is small, without testing the landmarks for repeatability across platforms and operators. For any study necessitating the combination of landmark measurements from different operators, the scanner pipeline will be better suited. The small scanning-related error indicates that by following the same scanning protocol, different operators can be involved in the scanning process without introducing significant error

    Carmela Pérez-Salazar, Cristina Tabernero y Jesús M. Usunáriz (eds.) Los poderes de la palabra. El improperio en la cultura hispánica del Siglo de Oro

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    Este atractivo libro reúne una selección de las ponencias presentadas en el Congreso Internacional “Improperios áureos. El insulto en la cultura hispánica del Siglo de Oro”, celebrado en la ciudad de Corella, España, los días 14 y 15 de abril de 2011, actividad que reunió 21 especialistas de las letras y de la cultura española de los siglos XVI y XVII, para presentar distintos aspectos del proyecto multidisciplinar desarrollado por el Grupo de Investigación del Siglo de Oro, GRISO, de la Univ..

    Uncovering the genomic and metagenomic research potential in old ethanol-preserved snakes

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    Natural history museum collections worldwide represent a tremendous resource of information on past and present biodiversity. Fish, reptiles, amphibians and many invertebrate collections have often been preserved in ethanol for decades or centuries and our knowledge on the genomic and metagenomic research potential of such material is limited. Here, we use ancient DNA protocols, combined with shotgun sequencing to test the molecular preservation in liver, skin and bone tissue from five old (1842 to 1964) museum specimens of the common garter snake (Thamnophis sirtalis). When mapping reads to a T. sirtalis reference genome, we find that the DNA molecules are highly damaged with short average sequence lengths (38–64 bp) and high C-T deamination, ranging from 9% to 21% at the first position. Despite this, the samples displayed relatively high endogenous DNA content, ranging from 26% to 56%, revealing that genome-scale analyses are indeed possible from all specimens and tissues included here. Of the three tested types of tissue, bone shows marginally but significantly higher DNA quality in these metrics. Though at least one of the snakes had been exposed to formalin, neither the concentration nor the quality of the obtained DNA was affected. Lastly, we demonstrate that these specimens display a diverse and tissue-specific microbial genetic profile, thus offering authentic metagenomic data despite being submerged in ethanol for many years. Our results emphasize that historical museum collections continue to offer an invaluable source of information in the era of genomics

    Grey seal Halichoerus grypus recolonisation of the southern Baltic Sea, Danish Straits and Kattegat

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    The grey seal became locally extinct in the southern Baltic Sea, Danish Straits and Kattegat in the early 1900s after prolonged culling campaigns. Here, we combine national monitoring and anecdotal data from Denmark, Sweden, Germany and Poland to report on the grey seal's recolonisation of those areas and the initial reestablishment of breeding colonies. Grey seal occurrence has steadily increased since year 2003 as evidenced by the coordinated Baltic Sea moult censuses. At the first census in 2003, there were 146 grey seals along the southern Baltic coasts of Sweden and Denmark, ca 1% of the total Baltic Sea population count. Since 2015, this has increased to 2000–2600 grey seals, or ca 7% of the total population count. Since the local extinction, there have been sporadic breeding events in the 1940s on sea ice around Bornholm and in the 1980s and 1990s on haul-outs in Kattegat. In 2003, the first two pups in the southern Baltic Sea were recorded at Rødsand, Denmark. This is to date the only site in the southern Baltic Sea with regular annual pupping since the recolonisation. Since 2000, there have also been sporadic breeding events in Danish Kattegat, southern Sweden, Poland and Germany. At Rødsand, there have been at least 3–10 pups recorded every year since initiation of monitoring in 2011, with an increasing tendency until 2017 with 10 pups counted, which subsequently decreased to 5–6 pups annually in 2018–2020. Compared to recolonising events in the Atlantic, the numbers of pups are low. This may be caused by differences in population dynamics, recolonisation distances, habitat and mortality and effects of rehabilitation programmes. It is likely that the breeding distribution will spread throughout the southern Baltic, Danish Straits and Kattegat if appropriate protection measures of seals and haul-outs are installed

    Using virtual reality for anatomical landmark annotation in geometric morphometrics

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    To study the shape of objects using geometric morphometrics, landmarks are oftentimes collected digitally from a 3D scanned model. The expert may annotate landmarks using software that visualizes the 3D model on a flat screen, and interaction is achieved with a mouse and a keyboard. However, landmark annotation of a 3D model on a 2D display is a tedious process and potentially introduces error due to the perception and interaction limitations of the flat interface. In addition, digital landmark placement can be more time-consuming than direct annotation on the physical object using a tactile digitizer arm. Since virtual reality (VR) is designed to more closely resemble the real world, we present a VR prototype for annotating landmarks on 3D models. We study the impact of VR on annotation performance by comparing our VR prototype to Stratovan Checkpoint, a commonly used commercial desktop software. We use an experimental setup, where four operators placed six landmarks on six grey seal (Halichoerus grypus) skulls in six trials for both systems. This enables us to investigate multiple sources of measurement error. We analyse both for the configuration and for single landmarks. Our analysis shows that annotation in VR is a promising alternative to desktop annotation. We find that annotation precision is comparable between the two systems, with VR being significantly more precise for one of the landmarks. We do not find evidence that annotation in VR is faster than on the desktop, but it is accurate
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