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Abstract Sea turtle stranding events provide an opportunity to study drivers of mortality, but causes of strandings are poorly understood. A general sea turtle carcass oceanographic drift model was developed to estimate likely mortality locations from coastal sea turtle stranding records. Key model advancements include realistic direct wind forcing on carcasses, temperature driven carcass decomposition and the development of mortality location predictions for individual strandings. We applied this model to 2009–2014 stranding events within the Chesapeake Bay, Virginia. Predicted origin of vessel strike strandings were compared to commercial vessel data, and potential hazardous turtle-vessel interactions were identified in the southeastern Bay and James River. Commercial fishing activity of gear types with known sea turtle interactions were compared to predicted mortality locations for stranded turtles with suggested fisheries-induced mortality. Probable mortality locations for these strandings varied seasonally, with two distinct areas in the southwest and southeast portions of the lower Bay. Spatial overlap was noted between potential mortality locations and gillnet, seine, pot, and pound net fisheries, providing important information for focusing future research on mitigating conflict between sea turtles and human activities. Our ability to quantitatively assess spatial and temporal overlap between sea turtle mortality and human uses of the habitat were hindered by the low resolution of human use datasets, especially those for recreational vessel and commercial fishing gear distributions. This study highlights the importance of addressing these data gaps and provides a meaningful conservation tool that can be applied to stranding data of sea turtles and other marine megafauna worldwide. Highlights • Development of a general turtle carcass oceanographic drift model • Improvement in our ability to predict sea turtle mortality from stranding data • Identified potential locations of hazardous turtle-human interactions in Virginia • Quantitative assessments hindered by the low resolutions of human use datasets [ABSTRACT FROM AUTHOR]

On 20 January 1990, twenty-three Tursiops truncatus (Common Bottlenose Dolphin) carcasses were found scattered around the interior shoreline of East Matagorda Bay, TX. Few accounts exist to document the presence of live or dead Common Bottlenose Dolphins inside the boundaries of East Matagorda Bay before or after the die-off. We conducted a review of areal data for East Matagorda Bay and the original investigation of the January 1990 mass die-off. Information we examined included the history of natural and anthropogenic changes to the area, dolphin stranding records, small-boat visual surveys, and dolphin dorsal-fin photographic identification. Natural events preceding the discovery of the dolphin carcasses were likely factors in the mortalities; however, the timing of engineering projects that modified access points between the bay and the Gulf of Mexico may be an additional factor that contributed to the cause of this unusual mortality event. [ABSTRACT FROM AUTHOR]

Five melon-headed whales (Peponocephala electra) were reported as single strandings on the beaches of the eastern (Atlantic) coast of the Caribbean island of Trinidad between March 2013 and November 2015. We examined four of the five reported cases. Animals displayed a loss of equilibrium and repeatedly restranded following reflotation attempts. One animal died naturally at the stranding site, while three were euthanized after unsuccessful reflotation attempts. Eggs and/or adult trematodes (Nasitrema species) were identified in the brain of all cases and were generally associated with multifocal moderate pyogranulomatous meningoencephalitis. Peritoneal parasitic (cestode) cysts, gastrointestinal helminthiasis, and ulcerative gastritis associated with anisakid nematode infestation were also common findings across specimens. To date, no other stranded cetaceans examined on the island have been similarly affected. The findings presented herein strongly suggest that Nasitrema species-associated encephalitis is a common cause of melon-headed whale strandings in the southeastern Caribbean. [ABSTRACT FROM AUTHOR]

The incidence of cetacean strandings is expected to depend on a combination of factors, including the distribution and abundance of the cetaceans, their prey, and causes of mortality (e.g. natural, fishery bycatch), as well as currents and winds which affect whether carcasses reach the shore. We investigated spatiotemporal patterns and trends in the numbers of strandings of three species of small cetacean in Galicia (NW Spain) and their relationships with meteorological, oceanographic, prey abundance and fishing-related variables, aiming to disentangle the relationship that may exist between these factors, cetacean abundance and mortality off the coast. Strandings of 1166 common dolphins ( Delphinus delphis), 118 bottlenose dolphins ( Tursiops truncatus) and 90 harbour porpoises ( Phocoena phocoena) during 2000-2013 were analysed. Generalised additive and generalised additive-mixed model results showed that the variables which best explained the pattern of strandings of the three cetacean species were those related with local ocean meteorology (strength and direction of the North-South component of the winds and the number of days with South-West winds) and the winter North Atlantic Oscillation Index. There were no significant relationships with indices of fishing effort or landings. Only bottlenose dolphin showed possible fluctuations in local abundance over the study period. There was no evidence of long-term trends in number of strandings in any of the species and their abundances were, therefore, considered to have been relatively stable during the study period. [ABSTRACT FROM AUTHOR]

The occurrence of cetaceans around subantarctic Macquarie Island is poorly known. The current study provides the first quantitative assessment of the occurrence of various cetacean species in inshore waters during 391 systematic, one- hour observation periods over 59 weeks, in 2002 and 2003. Nine species of cetacean were identified during these surveys. Killer whales, long-finned pilot whales and sperm whales were all detected with some frequency. All other species were detected on single occasions. Eight previously unpublished stranding records are also summarised. These results support the notion that most cetacean species are relatively uncommon in the inshore waters of Macquarie Island. Routine archiving of cetacean sightings obtained during shipping activities in surrounding waters is encouraged as this will further contribute to our understanding of the region's marine megafauna. [ABSTRACT FROM AUTHOR]

The beaching and disposal of the carcase of a 25t humpback whale was observed in the Strand, South Africa, just before Christmas in 2015. Despite the impending holiday, municipal services needed to dispose of the carcase timeously to prevent a risk to public health. As the beaching of whales in Cape Town occurs not infrequently, a protocol does exist. The carcase was dragged off the rocks and up the beach by bulldozers. After the road was closed, it was loaded on to a low bed trailer parked near the sea wall. As the trailer proved to be too small, it was reloaded on to a larger, replacement trailer. The carcase was then driven to the municipal landfill site at Vissershok for disposal. Background information is provided about the migratory habits of the Humpback whales that brought this specimen to Cape waters in the first place. Whale hunting in False Bay before the international moratorium in 1982 is also described. [ABSTRACT FROM PUBLISHER]

Over the past 5 years, massive accumulations of holopelagic species of the brown macroalga Sargassum in coastal areas of the Caribbean have created 'golden tides' that threaten local biodiversity and trigger economic losses associated with beach deterioration and impact on fisheries and tourism. In 2015, the first report identifying the cause of these extreme events implicated a rare form of the holopelagic species Sargassum natans (form VIII). However, since the first mention of S. natans VIII in the 1930s, based solely on morphological characters, no molecular data have confirmed this identification. We generated full-length mitogenomes and partial chloroplast genomes of all representative holopelagic Sargassum species, S. fluitans III and S. natans I alongside the putatively rare S. natans VIII, to demonstrate small but consistent differences between S. natans I and VIII (7 bp differences out of the 34,727). Our comparative analyses also revealed that both S. natans I and S. natans VIII share a very close phylogenetic relationship with S. fluitans III (94- and 96-bp differences of 34,727). We designed novel primers that amplified regions of the cox2 and cox3 marker genes with consistent polymorphic sites that enabled differentiation between the two S. natans forms ( I and VIII) from each other and both from S. fluitans III in over 150 Sargassum samples including those from the 2014 golden tide event. Despite remarkable gene synteny and sequence conservation, the three Sargassum forms differ in morphology, ecology, and distribution patterns, warranting more extensive interrogation of holopelagic Sargassum genomes as a whole. [ABSTRACT FROM AUTHOR]

During spring 2017, starting from 12 May, exceptional strandings of the purple snail Janthina pallida were recorded in the Ligurian Sea and along the western coast of Sardinia Island, under the effect of southern winds. The strandings continued for 3 days, until 15 May, when the winds shifted to the northern quadrant and the specimens were drifted back offshore. Such extensive strandings have never been previously reported in the scientific literature, either along the Mediterranean shores or elsewhere. Thanks to citizens' help, it was possible to create a map of the strandings and obtain a gross estimate of the number of beached gastropods. The densities of the stranded animals reached an overall average of 801 ± 215 specimens m−2 (with peaks of over 2000 shells and rafts m−2 densely packed with hydrozoan Velella velella sails), corresponding to an average biomass of about 1.5 kg m−2. The size–frequency distribution of the shell heights showed a bi-modal trend, as is usual in the case of sequential hermaphroditism: almost all the specimens fitting the first mode (11 mm) showed a raft without eggs (males), while all the specimens belonging to the largest mode (23 mm) had rafts with settled egg cases (females). The general trend of the sea currents in the North-western Mediterranean Basin explains the spatial distribution of the strandings following 3 days of constant southern moderate breeze (up to 28 km h−1). The presence of such huge J. pallida banks in the Ligurian Sea is stochastic, probably linked to an Atlantic population entering through the Gibraltar Strait, as evidenced by the simultaneous presence of the buoy barnacle, Dosima fascicularis, a circumtropical species recorded here for the second time in the Mediterranean Sea. [ABSTRACT FROM AUTHOR]

The periodic trend to cetacean mass stranding events in the Australian island state of Tasmania remains unexplained. This article introduces the hypothesis that domoic acid poisoning may be a causative agent in these events. The hypothesis arises from the previously evidenced role of aeolian dust as a vector of iron input to the Southern Ocean; the role of iron enrichment in Pseudo- nitzschia bloom proliferation and domoic acid production; and importantly, the characteristic toxicosis of domoic acid poisoning in mammalian subjects leading to spatial navigation deficits. As a pre-requisite for quantitative evaluation, the plausibility of this hypothesis was considered through correlation analyses between historical monthly stranding event numbers, mean monthly chlorophyll concentration and average monthly atmospheric dust loading. Correlation of these variables, which under the domoic acid stranding scenario would be linked, revealed strong agreement (r = 0.80-0.87). We therefore advocate implementation of strategic quantitative investigation of the role of domoic acid in Tasmanian cetacean mass stranding events. [ABSTRACT FROM AUTHOR]

In this study, we analyse seasonal aspects of harbour porpoise strandings in the Sea of Azov and discuss factors affecting the stranding rate. Data on 633 strandings were obtained from monitoring of a 35-km long area of the south coast of the Sea of Azov in 1999-2013. A distinct peak of strandings fell in July and August: it depended on the bycatch peak and calving season. Stranding rates depended neither on weather conditions nor on the seasonal fishing activities (including IUU fisheries). Moreover, stranding peaks in the neighbouring Black Sea were also tied to the calving season rather than to the fishing activities. We suggest that the seasonal mortality patterns are indirectly determined by nutritional stress: in Atlantic, winter-stranding oceanic populations and summer-stranding inner-sea populations occur that also possibly differ in the seasonal dynamics of body mass, weaning time or duration of mother--calf association, and dentine structure. In a typical summer-stranding population, summer is the season of nutritional stress, parturition, independent foraging of yearlings and lactation of nursing females, which leads to the risky foraging behaviour near gillnets. Another possible factor of increased bycatch is the seasonal habitat preference, corresponding to the gillnet preferences. Therefore, stranding and by catch seasonality of porpoises can largely be explained by the aspects of their life history and foraging behaviour rather than by weather conditions and fisheries. This supports the time--area closure strategy as an adequate conservation measure, which would consider minimizing the conflict of interest with fisheries. [ABSTRACT FROM AUTHOR]

Long-term monitoring of cetacean strandings is essential for good management. This study updates previous summaries for South Australia by adding up to 20 years of comprehensive data, including results of necropsy examinations. A total of 1078 records were examined. Thirty-one species were recorded: 9 (7% of records) mysticetes, 22 (88%) odontocetes and the rest (5%) unidentified. The number of species new to South Australia did not reach an asymptote, with potential for at least five additional species. Small cetaceans were more frequently recorded after 1990, possibly due to increased reporting effort. Stranding records increased markedly after 1970. Records for all species occurred year-round. Beaked whales stranded primarily during January-April, baleen whales during July-January and common dolphins during February-May. Geographic hotspots were identified and related to upwelling and reporting effort. A necropsy program since 1990 resulted in 315 of 856 records being assigned to a circumstance of death, with anthropogenic circumstances accounting for 42% of these. Known Entanglement (21%, 66 of 315) and Probable Entanglement (12%, 37 of 315) were the most recorded anthropogenic circumstances of death. Future research correlating strandings with oceanographic/climatic conditions may help to explain the documented patterns but first the effects of reporting effort need to be accounted for. [ABSTRACT FROM AUTHOR]

Oil–shoreline interaction (or “beaching” as commonly referred to in literature) is an issue of major concern in oil spill modeling, due to the significant environmental, social and economic importance of coastal areas. The present work studies the improvement of the representation of beaching brought by the introduction of the Oil Holding Capacity approach to estimate oil concentration on coast, along with new approaches for coast type assignment to shoreline segments and the calculation of permanent oil attachment to the coast. The above were tested for the Lebanon oil spill of 2006, using a modified version of the open-source oil spill model MEDSLIK-II. The modified model results were found to be in good agreement with field observations for the specific case study, and their comparison with the original model results denote the significant improvement in the fate of beached oil brought by the proposed changes. [ABSTRACT FROM AUTHOR]

Marine vertebrate strandings offer an opportunistic sampling scheme that can provide abundant data over long periods. Because the stranding process involves biological, physical and sociological parameters, confounding complicates the interpretation of results. The statistical analysis of these data relies on generalized linear or additive models in order to infer long-term trends, but does not easily account for drift or variation in reporting rates. Here, we capitalized on county-level (administrative) variation following the passing of a law for compulsory reporting of stranded marine mammals in France to investigate how variation in reporting rates may affect the observed trend in stranded small delphinids in the Bay of Biscay. Using a time-series spanning more than 30 years across eight administrative counties, we built variance partitioning models for the analysis of count data. We discussed the choice of an appropriate likelihood to conclude the Negative Binomial useful and interpretable in the context of small delphinid strandings. We expanded the model with a recent methodology to detect structural breaks in the time series, focusing on overdispersion. We performed statistical robustness checks with respect to variations in reporting rates and discuss their causal interpretation in the context of observational data. Stranding frequencies increased on average 7-fold over 30 years. We conclude that reporting rates to the French stranding network have been stable since the early 1990s, and the average 3-fold increase in stranded small delphinids observed in the Bay of Biscay since 1990 is due to other factors, including bycatch. Codes and data are available to replicate the analysis to other national stranding networks. [ABSTRACT FROM AUTHOR]

Abstract: Large numbers of swimming and stranding Urechis unicinctus were observed at night during low tide in Sasuhama, Miyagi Prefecture, northeastern Japan, during the periods from January to February in 2012 and 2013. Worms did not drift passively but swam actively, therefore hinting at a certain purpose for such behavior. As trochophore larvae of U. unicinctus were observed to occur simultaneously in the plankton, we infer the possibility that this is an event of reproductive swarming. Anatomical observations of both swimming and stranding U. unicinctus showed that none of the specimens had gametes, which may suggest that these were completely spent after spawning. Urechis unicinctus seemed to begin swimming after dusk and the observed swimming behavior occurred during the evening ebb tide throughout the night low tide during winter time. Stranding U. unicinctus have long been known in Japan and have been attributed to sea storms. The present study shows for the first time the possibility that U. unicinctus swims in order to reproduce at night and that this swimming behavior is closely linked to the stranding of U. unicinctus individuals. [Copyright &y& Elsevier]

The article presents a study which discusses the refloating of bottlenose dolphins (Tursiops truncatus) and the subsequent resighting with a neonate in Ireland. Topics include the live-stranding events of a bottlenose dolphin, the function of the Shannon Dolphin and Wildlife Foundation (SDWF), and the significant impact of the stranding events.

Reproductive seasonality of common bottlenose dolphins ( Tursiops truncatus) can be affected by numerous ecological and behavioral factors. In 2009, stock boundaries were revised to recognize a Charleston Estuarine System Stock ( CESS) of bottlenose dolphins in Charleston, South Carolina. The CESS is a well-studied population with long-term data collected from photo-identification and stranding studies. From 2004 to 2008, a systematic mark-recapture photo-identification study was conducted in the Charleston Estuary to estimate population size of the CESS. Sightings data from this photo-identification study coupled with strandings data (1993-2008) were analyzed to determine the reproductive seasonality of this local population. Both neonate sightings and strandings depicted a primary season of reproduction in the spring into early summer with a small peak in neonate sightings in early autumn, and were significantly different from circular uniform and Von Mises distributions (strandings: P < 0.01, V = 2.8644; sightings: P < 0.01, V = 3.2302). This study increases the knowledge of seasonal reproductive patterns of estuarine stocks of bottlenose dolphin stocks in the southeastern United States. The results will also help wildlife managers detect unusual neonate mortality events, and provide information about critical habitat relevant for evaluating and mitigating coastal development projects. [ABSTRACT FROM AUTHOR]

The chronic toxicity to rainbow trout ( Oncorhynchus mykiss) embryos of heavy fuel oil (HFO) 6303, weathered HFO 6303, HFO 7102, and medium South American (MESA) crude oil was assessed by different exposure regimes. These included water accommodated fractions (WAF; water in contact with floating oil), chemically enhanced WAF (CEWAF; oil dispersed with Corexit 9500), and effluent from columns of gravel coated with stranded oil. Heavy fuel oil WAF was nontoxic and did not contain detectable concentrations of hydrocarbons, likely because the high density and viscosity of HFO prevented droplet formation. In contrast, chemically dispersed HFO and effluent from columns of stranded HFO contained measurable concentrations of alkyl polycyclic aromatic hydrocarbons (PAH), coincident with embryo toxicity. These exposure regimes enhanced the surface area of oil in contact with water, facilitating oil-water partitioning of hydrocarbons. Heavy fuel oil was consistently more toxic to fish than crude oil and the rank order of alkyl PAH concentrations in whole oil were sufficient to explain the rank order of toxicity, regardless of exposure method. Thus, the propensity of HFO to sink and strand in spawning shoals creates a long-term risk to developing fish because of the sustained release of PAHs from HFO to interstitial waters. Further, PAH monitoring is key to accurate risk assessment. Environ Toxicol Chem 2014;33:677-687. © 2013 SETAC [ABSTRACT FROM AUTHOR]

The adjacency of 2 marine biogeographic regions off Cape Hatteras, North Carolina (NC), and the proximity of the Gulf Stream result in a high biodiversity of species from northern and southern provinces and from coastal and pelagic habitats. We examined spatiotemporal patterns of marine mammal strandings and evidence of human interaction for these strandings along NC shorelines and evaluated whether the spatiotemporal patterns and species diversity of the stranded animals reflected published records of populations in NC waters. During the period of 1997-2008, 1847 stranded animals were documented from 1777 reported events. These animals represented 9 families and 34 species that ranged from tropical delphinids to pagophilic seals. This biodiversity is higher than levels observed in other regions. Most strandings were of coastal bottlenose dolphins (Tursiops truncatus) (56%), harbor porpoises (Phocoena phocoena) (14%), and harbor seals (Phoca vitulina) (4%). Overall, strandings of northern species peaked in spring. Bottlenose dolphin strandings peaked in spring and fall. Almost half of the strandings, including southern delphinids, occurred north of Cape Hatteras, on only 30% of NC's coastline. Most stranded animals that were positive for human interaction showed evidence of having been entangled in fishing gear, particularly bottlenose dolphins, harbor porpoises, short-finned pilot whales (Globicephala macrorhynchus), harbor seals, and humpback whales (Megaptera novaeangliae). Spatiotemporal patterns of bottlenose dolphin strandings were similar to ocean gillnet fishing effort. Biodiversity of the animals stranded on the beaches reflected biodiversity in the waters off NC, albeit not always proportional to the relative abundance of species (e.g., Kogia species). Changes in the spatiotemporal patterns of strandings can serve as indicators of underlying changes due to anthropogenic or naturally occurring events in the source populations. [ABSTRACT FROM AUTHOR]

Despite years of collecting anecdotal and scientific information of cetaceans around Puerto Rico, the false killer whale ( Pseudorca crassidens), was never reported. Here, we report the first stranding and sighting event to take place in Puerto Rico in January, and March 2013, respectively. Both events took place along the south coast of Puerto Rico. During the sighting, cooperative prey sharing tactics were observed when two animals appeared to attack a common dolphinfish ( Coryphaena hippurus). [ABSTRACT FROM AUTHOR]

Abstract: Essential (Cu, Mn, Se and Zn) and non-essential (Cd and Hg) elements were analyzed in the hepatic tissue of 22 individuals of seven different species of small cetaceans (Feresa attenuata; Orcinus orca; Pontoporia blainvillei; Sotalia guianensis; Stenella frontalis; Steno bredanensis; Tursiops truncatus) accidentally caught in fishing nets or found stranded along the northern coast of the state of Rio de Janeiro, Brazil, between 2001 and 2010. Atlantic spotted dolphin (S. frontalis) showed the highest levels of Cd (20.23μgg−1, dry weight), while rough-toothed dolphin (S. bredanensis) showed the highest levels of Hg (825.9μgg−1 dw) and Se (221.9μgg−1 dw). Killer whale (O. orca) presented the highest levels of Cu (64.80μgg−1 dw) and Zn (2220μgg−1 dw), and Guiana dolphin (S. guianensis), the highest level of Mn (13.05μgg−1 dw). Cu, Hg, Mn and Zn in the hepatic tissue of killer whale (O. orca), Cu, Hg, Mn, Se and Zn in the hepatic tissue of rough-toothed dolphin (S. bredanensis) and Cd and Zn in the hepatic tissue of Guiana dolphin (S. guianensis) were significantly higher when compared to other studies with these species around the world. No significant correlations were observed between element accumulation and sex, sexual maturity and body length. An analysis of the interelemental relationships in the Guiana dolphin specimens showed strong positive correlations between Cd and Se, Cu and Zn, and Hg and Se. Differences were observed in the bioaccumulation of elements between the analyzed species, probably related to each species feeding habit, and differences between different element concentrations in the different dolphin species were probably due to the preference for certain preys and their bioavailability in the environment. Thus, the bioavailability of the analyzed elements in the marine environment should also be taken in consideration. This study also presents the first data ever reported for pygmy killer whale (F. attenuata) regarding trace element concentrations in hepatic tissue. [Copyright &y& Elsevier]

Until recently, few data were available for evaluating postintervention survival of free-ranging cetaceans receiving aid from humans through: rescue from stranding, with rehabilitation and release; rescue, rehabilitation and release of debilitated or entangled individuals that had not beached; rescue of entangled animals with immediate release; and rescue, transport, and release of out-of-habitat animals. Advances in medical diagnosis, husbandry and therapy have improved survival of rehabilitation cases, and advances in radio-telemetry have improved postrelease monitoring. In total, 69 cases (1986-2010) were evaluated, involving 10 species of odontocete cetaceans with release data. Findings suggested a success criterion of surviving at least six weeks postrelease is useful in evaluating intervention strategies. No species had better success than others. Stranded beached cetaceans were less successful than free-swimming rescued animals. Rehabilitated animals were less successful than those released without rehabilitation. Mass stranded dolphins fared better than single stranded animals. Old age, diminished hearing ability, and lack of maternal care were factors in several unsuccessful cases. Success is not clearly related to rehabilitation duration. Retaining healthy individuals from mass strandings until all animals are ready for release may reduce success for some. Transport durations for unsuccessful cases were greater than for successful cases. [ABSTRACT FROM AUTHOR]

The effects of climate change on high latitude regions are becoming increasingly evident, particularly in the rapid decline of sea ice cover in the Arctic. Many high latitude species dependent on sea ice are being forced to adapt to changing habitats. Harp seals (Pagophilus groenlandicus) are an indicator species for changing high-latitude ecosystems. This study analyzed multiple factors including ice cover, demographics, and genetic diversity, which could affect harp seal stranding rates along the eastern coast of the United States. Ice cover assessments were conducted for the month of February in the Gulf of St. Lawrence whelping region from 1991–2010 using remote sensing data, and harp seal stranding data were collected over the same time period. Genetic diversity, which may affect how quickly species can adapt to changing climates, was assessed using ten microsatellite markers to determine mean d2 in a subset of stranded and by-caught (presumably healthy) seals sampled along the northeast U.S. coast. Our study found a strong negative correlation (R2 = 0.49) between ice cover in the Gulf of St. Lawrence and yearling harp seal strandings, but found no relationship between sea ice conditions and adult strandings. Our analysis revealed that male seals stranded more frequently than females during the study period and that this relationship was strongest during light ice years. In contrast, we found no significant difference in mean d2 between stranded and by-caught harp seals. The results demonstrate that sea ice cover and demographic factors have a greater influence on harp seal stranding rates than genetic diversity, with only a little of the variance in mean d2 among stranded seals explained by ice cover. Any changes in these factors could have major implications for harp seals, and these findings should be considered in the development of future management plans for the Arctic that incorporate climate variability. [ABSTRACT FROM AUTHOR]

In the last decade, a number of cetacean strandings have gas embolic pathology analogous to decompression sickness in man and experimental animals. Acute gas and fat embolic lesions have also been found in mass-stranded beaked whales causally linked to high-intensity anthropogenic mid-frequency sonar activities. Sporadic chronic gas embolic lesions have also been described. This communication describes a first case of numerous gas-filled fibrous cavities in the markedly enlarged liver of a dead adult male harbour porpoise stranded at the North Sea coast of Schleswig-Holstein, Germany. Additional pathological findings consisted of chronic parasitic granulomatous cholangiohepatitis, hepatic vein thrombosis, parasitic infestations of the bronchial tree and pulmonary blood vessels associated with bronchopneumonia and severe parasitic burden in both ear sinuses. The hepatic cavernous lesions are similar to those described in chronic gas bubble disease in other cetaceans, most likely resulting from decompression-related tissue supersaturation with nitrogen. [ABSTRACT FROM AUTHOR]

Mass strandings of whales and dolphins have puzzled biologists since Aristode. Aldiough environmental factors are often assumed to initiate strandings, social forces must also influence the dynamics of many of these events, particularly for the primary species involved in mass strandings, the long-finned pilot whales (Globicephala melas). Here, we test two hypotheses derived from common assumptions about die social dynamics of long-finned pilot whales by identifying maternal lineages from mtDNA haplotypes and inferring kinship from microsatellite genotypes of 490 individuals from 12 stranding events. Contrary to the "extended matriline" hypothesis, we found that muitiple maternal lineages were present in at least 9 of the 12 mass strandings. Contrary to the "kinship cohesion" hypothesis, we found no correlation between spatial distribution and kinship along the stranding beach. Most notably, we documented the spatial disruption of the expected proximity between mothers and their dependent calves. These results challenge the common assumption that kinship-based behavior, such as care-giving, are a primary factor in these mass strandings. We suggest instead that disruption of kinship bonds could result from interactions among unrelated social groups during feeding or mating aggregations, perhaps playing a causal role in these events. Our finding that dependent calves were often spatially separated or absent from their mothers has important implications for humane management of rescue efforts. To improve our understanding of the social causes and consequences of mass strandings, future documentation of strandings should include exhaustive DNA sampling, with accompanying spatial and temporal records. [ABSTRACT FROM AUTHOR]

In the Western Brazilian Amazon, interactions of boto (Inia geoffrensis) and tucuxi (Sotalia fluviatilis) dolphins with fishing activities are common, but the prevalence of incidental/intentional catches is not known. This article describes incidental mortality events and intentional killing of I. geoffrensis and S. fluviatilis entangled in artisanal fishing gear and the opportunistic use of carcasses as bait. Between October 2010 and November 2011, surveys were conducted in waters of the lower Japurá River, between the Mamirauá and Amanã sustainable development reserves. In order to obtain information on interactions and to try to establish a stranding/entanglement response program (SERP), informal conversations were exchanged with local inhabitants (n = 174). Intense carcass-search surveys (n = 171) along the river in the four hydrological seasons (e.g., low, rising, high, and falling waters) were conducted, comprising a total of 1,197 h of sampling effort. Twenty-five dolphin-fishing interaction events were recorded (11 I. geoffrensis and 14 S. fluviatilis), 19 in 2011 and six in 2012 (through SERP). A total of 11 necropsies (three I. geoffrensis and eight S. fluviatilis) were performed. Four individuals (two I. geoffrensis and two S. fluviatilis) exhibited evidence of physical violence before death, and two (one I. geoffrensis and one S. fluviatilis) died in abandoned gillnets. Two intentional killing events of I. geoffrensis incidentally entangled for bait use in the piracatinga (Calophysus macropterus) fishery were reported by fishermen, while three carcasses (two I. geoffrensis and one S. fluviatilis) with gillnet marks were also used in that activity. At least six of the S. fluviatilis entanglement events occurred in fishing gear used for tambaqui (Colossoma macropomum) and pirapitinga (Piaractus brachypomus) (90/100-mm mesh-size gillnet), two of the most important commercial fish species in the Amazon Basin. As seasonal fishing constitutes the main income for riverine human populations, the negative reactions that cetacean presence causes to people could have a catalyst effect for the transition from "incidental capture" to "intentional capture and competitor removal." Law enforcement and precautionary measures through good fishing practices inside dolphin critical foraging areas should be taken together with fisheries' managers and fishermen to start to develop multiple-species management and ensure sustainable fishing practices. [ABSTRACT FROM AUTHOR]

Aims Alligatorweed (Alternanthera philoxeroides (Mart.) Griseb.) is an invasive species indigenous to South America. With its rapid invasion of southeastern US waterways, understanding the invasiveness of this plant species is critical for providing possible mechanisms of prevention for resource managers. The aim of this project is to use a matrix model to study the invasion dynamics of alligatorweed under both terrestrial and aquatic environments. The use of this model allows for a deeper understanding of the invasiveness and life history–stage structure of alligatorweed. In particular, matrix analysis can further test the hypothesis that certain life stages of alligatorweed might be more sensitive to control and management. Methods A greenhouse experiment was conducted to study the spread of alligatorweed under both aquatic and terrestrial environments. Utilizing the growth data obtained during the summer of 2010, matrix analysis was used to model the growth of alligatorweed for six different treatments. Transition matrices were generated based on plant measurements taken at different life stages defined by the number of leaves or nodes. These matrices are population projection models whose eigenvalues represent the growth rate of alligatorweed. A high growth rate is a key feature of successful invaders. Residuals were calculated and sensitivity analysis was performed to test the accuracy of the model and importance of each life stage over the entire life cycle of alligatorweed. Important findings The results of this study indicate that in the aquatic habitat, plants at their early life cycle stage are most sensitive to potential control measures. Conversely, in the terrestrial habitat, the most sensitive stage of alligatorweed is at its late life cycle stage, characterized with large-sized plants, thus suggesting the best timing for management and eradication of this invasive species. [ABSTRACT FROM AUTHOR]

This report describes for the first time the pathologic findings associated with mortality in 19 cetaceans (11 Atlantic bottlenose dolphins [Tursiops truncatus], 6 pygmy sperm whales [Kogia breviceps], and 2 short-finned pilot whales [Globicephala macrorhyncus]) which stranded along Florida's Atlantic northeastern coastline between May 2009-November 2011. The cause of death could be determined in most necropsied cases, which demonstrates the importance of performing gross and microscopic examinations on freshly stranded marine mammals. Causes of death in decreasing order of frequency were infectious/inflammatory disease, cardiomyopathy, starvation and congenital disease. The primary cause of death in dolphins and pilot whales was infectious/inflammatory disease (n=12) and in pygmy sperm whales cardiomyopathy (n=3). In cases of inflammatory/infectious disease, multisystemic disease was common. The primary inflammatory/ infectious disease lesions in decreasing order of frequency were pneumonia (n=9; 75%), gastroenteritis (n=6; 50%), hepatitis (n=3; 25%), meningitis (n=3; 25%), dermatitis/panniculitis (n=3; 25%) and pancreatitis (n=2; 17%). The primary cause of death in both this report and a similar study from the Indian River Lagoon (IRL), FL was similar. However, the prevalence of infectious/inflammatory disease in necropsied bottlenose dolphins in northeastern Florida was higher than that reported from the IRL. The prevalence of cardiomyopathy in pygmy sperm whales was similar to that reported in prior studies from other geographic regions of the eastern United States and Taiwan. Understanding the pathologic features associated with mortality in cetaceans is important for the future management of these species and may provide an insight into the health of the coastal ecosystem from this geographic region of Florida. [ABSTRACT FROM AUTHOR]

The article presents a first-time comprehensive data set of strandings on loggerhead (Caretta caretta) and green (Chelonia mydas) sea turtles along the eastern Mediterranean coast of Turkey. It discusses the methodology of the study which included collecting strandings during the nesting season, daily monitoring of beaches and identifying stranded turtles according to species. It presents a table indicating the population size of the loggerhead and green sea turtles per region.

The article describes the cetacean diversity of the Falkland (Malvinas) Island using the records collected of stranded specimens from the late 1800s to September 2012 and uses sighting data to provide a complete overall picture of the cetacean community. Records of dolphins and whales stranded in the Falkland Islands between 1866 to September 2012 were compiled in detail from different sources such as the British Museum of Natural History, the Falkland Islands Museum and scientific publications. It notes that the Falkland (Malvinas) Islands cetacean community has 24 species whose composition is similar to that reported in the southern waters of Argentina and Chile.

The health, postrelease movements, and behavior of mass stranded Atlantic white-sided dolphins ( Lagenorhynchus acutus) and short-beaked common dolphins ( Delphinus delphis) from Cape Cod, Massachusetts, were evaluated. Health was assessed through physical examination and blood analysis. Eleven dolphins (eight white-sided dolphins and three common dolphins) were relocated, outfitted with satellite transmitters, and released during seven mass stranding events. Five transmitters recorded only location, and six also included a time-depth recorder. Transmission duration ranged from 8 h to 218 d, with a mean of 117 d (median = 118 d, SD = 82 d), after release. All dolphins demonstrated extensive movement throughout the Gulf of Maine. The distribution of tagged dolphins was considered normal based on comparisons with published data for these species. Excluding the dolphin that transmitted for only 8 h, mean minimum speeds for individual dolphins ranged from 3.4 to 6.6 km/h; overall mean for all dolphins was 5.4 km/h (SD = 0.9 km/h). The five dolphins with time-depth recorders had mean dive depths of 8.6-40.3 m and mean dive durations of 46-296 s. Hematologic and biochemical data revealed only minor abnormalities. Data suggest that at least 10 of the 11 dolphins were likely successfully reintroduced into the wild. [ABSTRACT FROM AUTHOR]

In 2007, the apparent increase in the number of harbor porpoises (Phocoena phocoena) stranding along the central California coast compared to the number of strandings the previous year resulted in the declaration of an Unusual Mortality Event by the National Marine Fisheries Service. A statistically significant increase in strandings occurred in 2008 and 2009, with more than twice the mean annual number of strandings documented per year in the previous decade occurring each year, but then strandings decreased in 2010. No single cause of mortality explained all the strandings, and there were no significant changes in age class or sex of strandings in 2008 and 2009. Trauma, including interspecific aggression and fisheries interactions, was the most common cause of death, and blunt force trauma increased significantly in August through October of 2008 and 2009. Domoic acid toxicosis was documented for the first time in this species. Although the cause of death for many strandings was unidentified, the increase in strandings in 2008-2009 reflects an increase in blunt trauma rather than an epizootic of disease. [ABSTRACT FROM AUTHOR]

The article discusses a literature review of cetaceans in Maldives. It says that 21 cetaceans species have been recorded using the sightings surveys and acoustic surveys. It states that the species most frequently seen is the spinner dolphin, Stenella longirostris and the commonly reported stranding is the sperm whale, Physeter macrocephalus. It also mentions that all cetacean species are protected by the law within the Maldivian waters, particularly net fishing. Moreover, cetacean-watching has been popularly increasing with the spinner dolphin as the main attraction.

The article focuses on the records of marine mammals in Tanzania undertaken by the Marine Mammal Education and Research Group of the Institute of Marine Sciences in Roatan, Honduras in 1998. It mentions that most of the information on marine mammals was collected off the coast of Unguja Island and data gathering is undertaken through sampling procedure of strandings and bycatch marine mammals. The results show that from 1992 to 2008, 22 marine mammals were reported stranded. Moreover, the results also show that from January 2000 to December 2008, 213 bycatches and one dugong were reported.

In 2006-2007, an unusually high number of harbor porpoises ( Phocoena phocoena) stranded along the Washington and Oregon coastlines. Spatiotemporal analyses were used to examine their ability to detect clusters of porpoise strandings during an unusual mortality event (UME) in the Pacific Northwest using stranding location data. Strandings were evaluated as two separate populations, outer coast and inland waters. The presence of global clustering was evaluated using the Knox spatiotemporal test, and the presence of local clusters was investigated using a spatiotemporal scan statistic (space-time permutation). There was evidence of global clustering, but no local clustering, supporting the hypothesis that strandings were due to more varied etiologies instead of localized causes. Further analyses at subregional levels, and concurrently assessing environmental factors, might reveal additional geographic distribution patterns. This article describes the spatial analytical tools applied in this study and how they can help elucidate the spatiotemporal epidemiology of other UMEs and assist in determining their causes. More than one spatial analytical technique should be used if the study objective is to detect and describe clustering in time and space and to generate hypotheses regarding causation of marine mammal disease and stranding events. [ABSTRACT FROM AUTHOR]

The present article is the first formal record of pelagic swarms and beach strandings of the squat lobster Munida gregaria in the Beagle Channel, southern South America. To describe size composition and natural diet of beach strandings and swarms, samples from strandings were taken in April 2007, March 2008 and March 2010. Samples from swarms were taken in May 2007 and April 2010. Also, during November 2008 and January 2009, two acoustic surveys were carried out to describe both, horizontal distribution and school metrics of swarms. Pelagic swarms and beach strandings were composed of 100% individuals of the morph gregaria of M. gregaria. Mean size of males and females in both, beach strandings and swarms, were similar. The diet of pelagic M. gregaria was composed mainly of crustaceans, unicellular algae and small macroalgae, sediment and particulate organic matter. Swarms of pelagic Munida took the shape of extended layers of varying density and height. Their positions in the water column were also variable: swarms were found at different depths, from the subsurface layer to near the sea bottom. Occasionally, some large swarms occupied most of the water column. In the Beagle Channel, SW winds during spring tides could be a forcing factor for M. gregaria strandings. The absence of shoaling animals in the Beagle Channel between 1997 and 2002 and the recent occurrence of swarms are coincident with their appearance in other locations in Patagonia. In consequence, we hypothesize that the factor influencing the formation of swarms must be acting at a regional scale. [ABSTRACT FROM AUTHOR]

We investigated the diet, feeding strategy, size-related dietary shifts and prey preferences of South American Hoplias aff. malabaricus in an internationally recognized but poorly investigated Biosphere Reserve in southern Brazil. Fish were caught between April 2008 and March 2009 using a variety of fishing gear. The analysis of 113 individuals revealed a diet essentially composed of fish (16 species), particularly characid species (9). The diet became more diverse and contained larger fish prey with increasing predator size. Feeding strategy analysis revealed a clear specialization towards the consumption of fish. However, individuals did not prey upon particular prey species, instead opportunistically consuming many different fish species, which could be a strategy to avoid intraspecific competition. Characid species were the most important prey, followed by poecillids. A multi-gear sampling of the ichthyofauna revealed that these prey species were the most abundant (Characidae: 61.3%, Poeciliidae 18.8%) of the 14 fish families occurring at the study site, suggesting that the predator exploits the most abundant fish resources available rather than the rarer fish prey. These findings suggest that potential top-down controls exerted by H. aff. malabaricus in this system follow specific food web pathways that seem to be mediated by the abundance of prey resources. [ABSTRACT FROM AUTHOR]

Abstract: The first mid-Atlantic diet of Mesoplodon beaked whales is presented, from ten Sowerby''s Mesoplodon bidens stranded in the Azores region between 2002 and 2009. This doubles the worldwide number of stomachs sampled, and reveals new feeding habits for this species. The mean number of prey items per stomach was 85±89 (range: 12–238), with fish accounting for 99.3% and cephalopods contributing less than 1% of total prey. Fish otoliths from 15 families and cephalopod lower mandibles from three families were identified, representing 22 taxa. The diet consisted mainly of small mid-water fish, the most numerous being Diaphus sp., Lampanyctus sp. and Melamphaidae species. Myctophids were present in all stranded individuals, followed by Diretmidae, Melamphaidae and Opisthoproctus soleatus, while the remaining fish species were scarce or single occurrences. Consistency of diet in four different years reveals a divergence from all previous records in continental areas, where mainly neritic and shelf-break benthopelagic fish species have been reported. Mid-Atlantic Sowerby''s beaked whales'' showed dietary plasticity, feeding on the most abundant mid-water groups occurring between 0 and750m. Trophic level from prey numerical frequency was estimated at 4.4±0.46. [Copyright &y& Elsevier]

The number and distribution of vocalizing groups of Blainville’s beaked whales (Mesoplodon densirostris) were analyzed before, during, and after multiship midfrequency active sonar operations at the US Navy’s Atlantic Undersea Test and Evaluation Center (AUTEC) in the Bahamas. Groups of foraging animals were isolated by detecting their echolocation clicks using an array of bottom-mounted hydrophones. Two datasets were evaluated consisting of 115 and 240 h of acoustic data in May 2007 and 2008, respectively. Vocal activity was observed to decline during active sonar exercises and increase upon cessation of sonar transmissions in both data sets. Vocal activity did not recover to preexposure levels in the postexposure time period in 2007 nor in the initial postexposure period in the 2008 data set. Clicks detected during sonar operations were generally found to be on the periphery of the hydrophone field and vocal durations declined for those groups that remained on the range in that time period. Receive levels were calculated for several vocal groups of whales and indicated that animals continued to forage when exposed to sonar at levels as high as 157 dB re: μ Pa. [ABSTRACT FROM AUTHOR]

Abstract: Entanglement in and ingestion of synthetic marine debris is increasingly recognized worldwide as an important stressor for marine wildlife, including marine mammals. Studying its impact on wildlife populations is complicated by the inherently cryptic nature of the problem. The coastal waters of British Columbia (BC), Canada provide important habitat for marine mammal species, many of which have unfavorable conservation status in the US and Canada. As a priority-setting exercise, we used data from systematic line-transect surveys and spatial modeling methods to map at-sea distribution of debris and 11 marine mammal species in BC waters, and to identify areas of overlap. We estimated abundance of 36,000 (CIs: 23,000–56,600) pieces of marine debris in the region. Areas of overlap were often far removed from urban centers, suggesting that the extent of marine mammal–debris interactions would be underestimated from opportunistic sightings and stranding records, and that high-overlap areas should be prioritized by stranding response networks. [Copyright &y& Elsevier]

Abstract: During February–April 2008, an unusual mortality event occurred in Texas coastal waters that resulted in over 100 bottlenose dolphin (Tursiops truncatus) deaths. This mortality event overlapped spatially and temporally with a harmful algal bloom (HAB) composed of the toxin-producing genera Dinophysis spp. and Prorocentrum spp., and was associated with shellfish bed closures due to HAB toxins. A bloom of the toxin-producing diatom Pseudo-nitzschia pungens was also detected in Texas coastal waters in early April, towards the end of the dolphin mortality event. Analysis of dolphin gastrointestinal contents collected during this event demonstrated the presence of the HAB toxins domoic acid and okadaic acid in association with these blooms, as well as evidence of brevetoxin exposure in the absence of an associated K. brevis bloom. Historical dolphin stranding data for Texas waters indicate seasonal stranding peaks similar to the present study, indicating a need for investigating potential HAB involvement in mass strandings in previous years and in future events. This study marks the first reported occurrence of okadaic acid in marine mammals, and documents a unique co-occurrence of multiple HAB toxins associated with an unusual mortality event. Texas waters harbor a high diversity of HAB events relative to other coastal regions, and this study highlights the importance of efforts to understand the impacts of such HAB events on the health of Texas marine wildlife. [Copyright &y& Elsevier]

The article examines the link between domoic acid-related strandings of the seasonally migratory California sea lion Zalophus californianus and regional occurrences of domoic acid-producing diatoms in Monterey Bay, California. Materials and methods used in the study are detailed. The abundance of toxic Pseudo-nitzschia in the study area during the study period is determined. Results indicate that the domoic acid level is highly correlated with cell abundances of two toxic Pseudo-nitzschia species.

A well-maintained marine mammal stranding database can be an invaluable tool in understanding not only strandings but also changes in the marine environment. This study aimed to examine the following aspects of marine mammal strandings in the Philippines: species composition, temporal (i.e., frequency of stranding per year and seasonality) and spatial (i.e., frequency of stranding per region and province) variation, proportions of alive or dead specimens, and stranding hotspots. In 2008, a systematic collection of data on strandings, including out-of-habitat incidents, resulted in an initial 12-year database—from 1998 to 2009. A total of 178 stranding events were recorded: 163 single, 10 mass, and 5 out-of-habitat strandings, with an average of 15 observed stranding events annually. Twenty-three of the 28 confirmed species of marine mammals in the Philippines were recorded to strand, including first-recorded specimens for the Indo-Pacific bottlenose dolphin (Tursiops aduncus), pygmy sperm whale (Kogia breviceps), and Longman's beaked whale (Indopacetus pacificus). The top five most frequent species to strand included spinner dolphin (Stenella longirostris) (n = 26), short-finned pilot whale (Globicephala macrorhynchus) (n = 14), melon-headed whale (Peponocephala electra) (n = 13), Risso's dolphin (Grampus griseus) (n = 11), and common bottlenose dolphin (T. truncatus) (n = 10). Dugongs (Dugong dugon) stranded seven times since 2001. Strandings occurred throughout the year with frequency significantly peaking during the northeast (NE) monsoon (November to March) season. Overall, Regions III (Central Luzon) and VII (Central Visayas) had the highest number of strandings (both n = 27) followed by Regions I (Ilocos) (n = 22) and V (Bicol) (n = 18). The following provinces or local government units were considered hotspots based on high number of strandings observed at each area: Zambales, Cagayan, Zamboanga City, Negros Oriental, Bohol, Pangasinan, and Bataan. Sixty-five percent of all documented stranding events involved live (n = 116) animals. This high percentage might be linked to dynamite fishing (causing acoustic trauma), fisheries interactions, or biotoxins from harmful algal blooms coupled to their foodweb. These strandings in general validate the diverse marine mammal assemblage in the Philippines and reveal the various environmental threats with which they deal. [ABSTRACT FROM AUTHOR]

A massive beaching and mortality of fishes occurred in Coliumo Bay, a shallow bay located along the coast of the eastern South Pacific Ocean on 3 January 2008. This stranding was a consequence of an abrupt decrease in the dissolved oxygen concentration throughout the whole water column, due to the effect of intense upwelling along the coast off central-southern Chile. The main objectives of this study were: (1) to characterize taxonomically and biologically the fish species assemblage present in this beaching; (2) to evaluate several physiological indicators for the condition of the beached species at the time of their death; and (3) to assess the possible cause–effect mechanisms involved in the fishes death and the changes that took place in the fish community throughout the time. In this beaching, 26 fish species were identified: 23 teleosts, one myxiniform and two elasmobranchs. Most beached specimens were juveniles. Haematological and histological evidence indicate that severe hypoxia that lasted for at least 48 h was the most plausible cause of death. The main conclusion of this study is that the presence of oxygen-poor equatorial sub-surface water in the shallow coastal zone due to intense regional-scale upwelling caused the fish stranding. Although the effect of the hypoxic event was severe for the fish assemblage of Coliumo Bay, the rapid recuperation observed suggests that hypoxic events at the local spatial scale can be buffered by migration processes from the fish community inhabiting close by areas non-affected by low oxygen conditions. The effect that severe hypoxic events may have on larger spatial scales remains unknown. [ABSTRACT FROM AUTHOR]

A mass stranding of false killer whales Pseudorca crassidens at Long Beach near the village of Kommetjie (34°8.18′ S, 18°9.77′ E) on the Cape Peninsula, South Africa, in May 2009 is described. The estimated size of stranded group was 55 animals, which is close to the median size of P. crassidens groups that have stranded previously in South Africa (58). Five of the stranded individuals succumbed, 36 were euthanised and 14 were rescued. This was the eighth known mass stranding of this species to occur in South Africa, with all these events occurring on the irregular south-west coast of the Western Cape province. [ABSTRACT FROM AUTHOR]

A group of 70 false killer whales Pseudorca crassidens and 124 bottlenose dolphins Tursiops sp., and a separate group of 13 Risso's dolphins Grampus griseus, assembled close inshore off a known mass-stranding site in St Helena Bay, South Africa, in October 2003. However, only a single Risso's dolphin attempted to strand and 13 bottlenose dolphins had to be shepherded out of the shallows the next day, the remainder leaving of their own accord. This is considered to be the first near-stranding phenomenon recorded for the region. [ABSTRACT FROM AUTHOR]

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The article presents a study which discussed a system for coding final diagnosis to investigate the cause of death of marine mammals stranded on Cape Cod and southeastern Massachusetts between 2000 and 2006. It is stated that factors such as disease, human interaction and predatory attack contributed to mass strandings. Aerobic culture was devised to determine the presence of aerobic and anaerobic bacteria. The findings of gross and histological pathology and ancillary testing of the causes of mortality were revealed.