Quantitative overview of marine debris ingested by marine megafauna
Kühn, Susanne ; Franeker, Jan Andries van - \ 2020
Marine Pollution Bulletin 151 (2020). - ISSN 0025-326X
Entanglement - Ingestion - Marine mammals - Plastic litter - Seabirds - Turtles
This review quantifies plastic interaction in marine biota. Firstly, entanglement and ingestion records for all marine birds, mammals, turtles, fish, and invertebrate species, are summarized from 747 studies. Marine debris affected 914 species through entanglement and/or ingestion. Ingestion was recorded for 701 species, entanglement was documented for 354 species. Secondly, the frequency of occurrence of ingestion per species (Sp-%FO) was extracted for marine birds, mammals and turtles. Thirdly, for seabird species, average numbers of plastics ingested per individual were determined. Highest Sp-%FO and average number of plastics were found in tubenosed seabirds with 41% of all birds analysed having plastics, on average 9.9 particles per bird. The Sp-%FO and average number of ingested particles is lower for most other species. However, for certain species, ingestion rates of litter are reason for serious concern. Standardized methods are crucial for future studies, to generate datasets that allow higher level ecosystem analyses.
Livestock-Associated meticillin-resistant Staphylococcus aureus in a young harbour seal (Phoca vitulina) with endocarditis
Rubio-Garcia, Ana ; Rossen, John W.A. ; Wagenaar, Jaap A. ; Friedrich, Alex W. ; Zeijl, Jan H. Van - \ 2019
Veterinary Record Case Reports 7 (2019)3. - ISSN 2052-6121
Bacterial diseases - Endocarditis - Infection - Marine mammals - MRSA - Phoca vitulina
A five-month-old male harbour seal was admitted for rehabilitation to the Sealcentre Pieterburen on November 16, 2015. During initial veterinary examination parasitic pneumonia and secondary bacterial pneumonia were suspected. Therefore, the seal received antiparasitic and antimicrobial treatment and appeared to recover but died unexpectedly after several weeks. Postmortem examination revealed a perforation in the aortic wall and histopathological examination of the aorta revealed mural necrosis with haemorrhage and suppurative to mixed inflammation. Bacterial culture resulted in isolation of a meticillin-resistant Staphylococcus aureus (MRSA) from the pericardial effusion. Subsequent culture of rectal swabs collected at arrival and during rehabilitation showed that the animal was already colonised with MRSA when admitted to the Sealcentre. MRSA has been isolated from marine mammals before, however, to our knowledge this is the first report of MRSA-Associated endocarditis in seals and the first time that livestock-Associated MRSA is reported in seals.
Brucella pinnipedialis in grey seals (Halichoerus grypus) and harbor seals (Phoca vitulina) in the Netherlands
Kroese, Michiel V. ; Beckers, Lisa ; Bisselink, Yvette J.W.M. ; Brasseur, Sophie ; Tulden, Peter W. van; Koene, Miriam G.J. ; Roest, Hendrik I.J. ; Ruuls, Robin C. ; Backer, Jantien A. ; Ijzer, Jooske ; Giessen, Joke W.B. van der; Willemsen, Peter T.J. - \ 2018
Journal of Wildlife Diseases 54 (2018)3. - ISSN 0090-3558 - p. 439 - 449.
Brucella pinnipedialis - Halichoerus grypus - MALDI-TOF MS - Marine mammals - MLST - MLVA-16 - Phoca vitulina - The Netherlands
Brucellosis is a zoonotic disease with terrestrial or marine wildlife animals as potential reservoirs for the disease in livestock and human populations. The primary aim of this study was to assess the presence of Brucella pinnipedialis in marine mammals living along the Dutch coast and to observe a possible correlation between the presence of B. pinnipedialis and accompanying pathology found in infected animals. The overall prevalence of Brucella spp. antibodies in sera from healthy wild grey seals (Halichoerus grypus; n=11) and harbor seals (Phoca vitulina; n=40), collected between 2007 and 2013 ranged from 25% to 43%. Additionally, tissue samples of harbor seals collected along the Dutch shores between 2009 and 2012, were tested for the presence of Brucella spp. In total, 77% (30/ 39) seals were found to be positive for Brucella by IS711 real-time PCR in one or more tissue samples, including pulmonary nematodes. Viable Brucella was cultured from 40% (12/30) real-time PCR-positive seals, and was isolated from liver, lung, pulmonary lymph node, pulmonary nematode, or spleen, but not from any PCR-negative seals. Tissue samples from lung and pulmonary lymph nodes were the main source of viable Brucella bacteria. All isolates were typed as B. pinnipedialis by multiple-locus variable number of tandem repeats analysis-16 clustering and matrix-assisted laser desorption ionization-time of flight mass spectrometry, and of sequence type ST25 by multilocus sequence typing analysis. No correlation was observed between Brucella infection and pathology. This report displays the isolation and identification of B. pinnipedialis in marine mammals in the Dutch part of the Atlantic Ocean.
Toxoplasma gondii in stranded marine mammals from the North Sea and Eastern Atlantic Ocean : Findings and diagnostic difficulties
Velde, Norbert van de; Devleesschauwer, Brecht ; Leopold, Mardik ; Begeman, Lineke ; IJsseldijk, Lonneke ; Hiemstra, Sjoukje ; IJzer, Jooske ; Brownlow, Andrew ; Davison, Nicholas ; Haelters, Jan - \ 2016
Veterinary Parasitology 230 (2016). - ISSN 0304-4017 - p. 25 - 32.
ELISA - IFA - Marine mammals - MAT - PCR - Seroprevalence - Toxoplasma gondii
The occurrence of the zoonotic protozoan parasite Toxoplasma gondii in marine mammals remains a poorly understood phenomenon. In this study, samples from 589 marine mammal species and 34 European otters (Lutra lutra), stranded on the coasts of Scotland, Belgium, France, The Netherlands and Germany, were tested for the presence of T. gondii. Brain samples were analysed by polymerase chain reaction (PCR) for detection of parasite DNA. Blood and muscle fluid samples were tested for specific antibodies using a modified agglutination test (MAT), a commercial multi-species enzyme-linked immunosorbent assay (ELISA) and an immunofluorescence assay (IFA). Out of 193 animals tested by PCR, only two harbour porpoise (Phocoena phocoena) cerebrum samples, obtained from animals stranded on the Dutch coast, tested positive. The serological results showed a wide variation depending on the test used. Using a cut-off value of 1/40 dilution in MAT, 141 out of 292 animals (41%) were positive. Using IFA, 30 out of 244 tested samples (12%) were positive at a 1/50 dilution. The commercial ELISA yielded 7% positives with a cut-off of the sample-to-positive (S/P) ratio ≥ 50; and 12% when the cut-off was set at S/P ratio ≥ 20. The high number of positives in MAT may be an overestimation due to the high degree of haemolysis of the samples and/or the presence of lipids. The ELISA results could be an underestimation due to the use of a multispecies conjugate. Our results confirm the presence of T. gondii in marine mammals in The Netherlands and show exposure to the parasite in both the North Sea and the Eastern Atlantic Ocean. We also highlight the limitations of the tests used to diagnose T. gondii in stranded marine mammals.
Harbour porpoise movement strategy affects cumulative number of animals acoustically exposed to underwater explosions
Aarts, Geert ; Benda-Beckmann, Alexander M. Von; Lucke, K. ; Özkan Sertlek, H. ; Bemmelen, Rob Van; Geelhoed, Steve C.V. ; Brasseur, Sophie ; Scheidat, Meike ; Lam, Frans Peter A. ; Slabbekoorn, Hans ; Kirkwood, Roger - \ 2016
Marine Ecology Progress Series 557 (2016). - ISSN 0171-8630 - p. 261 - 275.
Acoustics - Anthropogenic sound - Cumulative effects - Impact assessment - Individual-based model - Marine mammals - Population consequences of disturbance - Species distribution
Anthropogenic sound in the marine environment can have negative consequences for marine fauna. Since most sound sources are intermittent or continuous, estimating how many individuals are exposed over time remains challenging, as this depends on the animals' mobility. Here we explored how animal movement influences how many, and how often, animals are impacted by sound. In a dedicated study, we estimated how different movement strategies affect the number of individual harbour porpoises Phocoena phocoena receiving temporary or permanent hearing loss due to underwater detonations of recovered explosives (mostly WWII aerial bombs). Geo-statistical distribution models were fitted to data from 4 marine mammal aerial surveys and used to simulate the distribution and movement of porpoises. Based on derived dose-response thresholds for temporary (TTS) or permanent threshold shifts (PTS), we estimated the number of animals affected in a single year. When individuals were free-roaming, an estimated 1200 and 24 000 unique individuals would suffer PTS and TTS, respectively. This equates to respectively 0.50 and 10% of the estimated North Sea population. In contrast, when porpoises remained in a local area, fewer animals would receive PTS and TTS (1100 [0.47%] and 15 000 [6.5%], respectively), but more individuals would be subjected to repeated exposures. Because most anthropogenic sound-producing activities operate continuously or intermittently, snapshot distribution estimates alone tend to underestimate the number of individuals exposed, particularly for mobile species. Hence, an understanding of animal movement is needed to estimate the impact of underwater sound or other human disturbance.
Seasonal habitat-based density models for a marine top predator, the harbor porpoise, in a dynamic environment
Gilles, A. ; Viquerat, S. ; Becker, E.A. ; Forney, K.A. ; Geelhoed, S.C.V. ; Haelters, J. ; Nabe-Nielsen, J. ; Scheidat, M. ; Siebert, U. ; Sveegaard, S. ; Beest, F.M. Van; Bemmelen, R. Van; Aarts, G. - \ 2016
Ecosphere 7 (2016)6. - ISSN 2150-8925
Aerial surveys - Conservation - Generalized additive model - Harbor porpoise - Marine mammals - Marine spatial planning - North Sea - Species distribution modeling - Top predator
Effective species conservation and management requires information on species distribution patterns, which is challenging for highly mobile and cryptic species that may be subject to multiple anthropogenic stressors across international boundaries. Understanding species-habitat relationships can improve the assessment of trends and distribution by explicitly allowing high-resolution data on habitats to inform abundance estimation and the identification of protected areas. In this study, we aggregated an unprecedented set of survey data of a marine top predator, the harbor porpoise (Phocoena phocoena), collected in the UK (SCANS II, Dogger Bank), Belgium, the Netherlands, Germany, and Denmark, to develop seasonal habitat-based density models for the central and southern North Sea. Visual survey data were collected over 9 yr (2005-2013) by means of dedicated line-transect surveys, taking into account the proportion of missed sightings. Generalized additive models of porpoise density were fitted to 156,630 km of on-effort survey data with 14,356 sightings of porpoise groups. Selected predictors included static and dynamic variables, such as depth, distance to shore and to sandeel (Ammodytes spp.) grounds, sea surface temperature (SST), proxies for fronts, and day length. Day length and the spatial distribution of daily SST proved to be good proxies for "season," allowing predictions in both space and time. The density models captured seasonal distribution shifts of porpoises across international boundaries. By combining the large-scale international SCANS II survey with the more frequent, small-scale national surveys, it has been possible to provide seasonal maps that will be used to assist the EU Habitats and Marine Strategy Framework Directives in effectively assessing the conservation status of harbor porpoises. Moreover, our results can facilitate the identification of regions where human activities and disturbances are likely to impact the population and are especially relevant for marine spatial planning, which requires accurate fine-scale maps of species distribution to assess risks of increasing human activities at sea.