We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure no-reply@cambridge.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
This study provides the first investigation into quantities, types, and potential sources of anthropogenic beach litter in Sierra Leone. Beach litter surveys were conducted monthly at four sites over 11 months. A total of 72,901 litter items (1,246 kg dry weight) were categorised. Across all sites, an average of 1,657 items per 100 m (SD = 1,639) and 28.32 kg per 100 m (SD = 37.48) were recorded. Plastics accounted for 70% of the litter by count and 49% by weight. The three most abundant items by count were plastic bottles (25%), plastic caps and lids (13%), and plastic water sachets (12%). By weight, the three most abundant items were plastic bottles (36%), flip-flops (20%), and shoes (9%). Litter amounts decreased from wet to dry season. We provide the following policy recommendations: improving drinking water access and sanitation, waste management, infrastructure and behaviour change.
To inform water quality monitoring techniques and modeling at coastal research sites, this study investigated seasonality and trends in coastal lagoons on the eastern shore of Virginia, USA. Seasonality was quantified with harmonic analysis of low-frequency time-series, approximately 30 years of quarterly sampled data at thirteen mainland, lagoon, and ocean inlet sites, along with 4–6 years of high-frequency, 15-min resolution sonde data at two mainland sites. Temperature, dissolved oxygen, and apparent oxygen utilization (AOU) seasonality were dominated by annual harmonics, while salinity and chlorophyll-a exhibited mixed annual and semi-annual harmonics. Mainland sites had larger seasonal amplitudes and higher peak summer values for temperature, chlorophyll-a and AOU, likely from longer water residence times, shallower waters, and proximity to marshes and uplands. Based on the statistical subsampling of high-frequency data, one to several decades of low-frequency data (at quarterly sampling) were needed to quantify the climatological seasonal cycle within specified confidence intervals. Statistically significant decadal warming and increasing chlorophyll-a concentrations were found at a sub-set of mainland sites, with no distinct geographic patterns for other water quality trends. The analysis highlighted challenges in detecting long-term trends in coastal water quality at sites sampled at low frequency with large seasonal and interannual variability.
The Antarctic seaspider Pentanymphon antarcticum is a benthic species in the Southern Ocean, but little is known about its pathogen profile. In this study, we provide a draft genome for a new iridovirus species that has been identified using metagenomic techniques. The draft genome totals 157 260 bp and encodes 188 protein-coding genes. The virus shows greatest protein similarity to a ‘carnivorous sponge-associated iridovirus’ from a deep-sea sponge host. This study represents the first discovery of a pycnogonid iridovirus and the first iridovirus from the Antarctic region.
Clayey sediments of marine origin having sensitivities (ratio of undisturbed to remolded shear strength) as high as 1000 at a reduced salt concentration are found around Ariake Bay, Kyushu, Japan. The clay fraction of the sediments contains smectite as a principal mineral (33–42%) in contrast to the illitic composition of most previously described quick-clays. However, this smectite is a low-swelling type, and the Na-form expands only to about the same extent as the Ca-form and gives a sediment volume almost equal to that of the Ca-clay. This low-swelling smectite appears to consist of packets of unit layers even after saturation with Na, and thus reacts like the kaolinite or illite of conventional quick-clays.
Seabirds have been the messengers of marine plastics pollution since the 1950s, not long after plastics began to be commercially manufactured. In the decades since, a number of multilateral agreements have emerged to address marine plastics pollution that have been informed by research and monitoring on plastic ingestion in seabirds. Seabirds continue to serve as effective monitors for plastics pollution in the oceans, and increasingly of the chemical contamination from the marine environment as plastic additives and chemicals can adsorb and accumulate in seabirds’ tissues. Plastics pollution has far-reaching ecological impacts, but the motivation for addressing the issue has escalated rapidly at the international level. Seabirds are also the most globally threatened group of birds and require concerted conservation actions to mitigate population declines from multiple pressures. However, most policy mechanisms focus on the monitoring and mitigation of anthropogenically induced stressors, using seabird data, and often fail to include mechanisms to conserve the messengers. In this review, we discuss how research on the impacts of plastics on seabirds is used to inform policy and highlight the competing interests of monitoring and conservation that emerge from this approach. Finally, we discuss policy opportunities to ensure seabirds can continue to be the indicators of ocean health and simultaneously achieve conservation goals.
The terrestrial and marine biotypes of Madagascar are critical priorities for conservation, with almost unparalleled levels of endemism, species diversity and human threat for a land area of its size. Field inventories and molecular-based research conducted from the mid 1980s to present have greatly expanded knowledge of the country's biota, for some groups with nearly exponential growth in measures of species diversity. I provide updated measures of estimated species diversity between a book with 289 contributors, published in 2003 (The Natural History of Madagascar), and a full-scale update with 539 contributors, published in 2022 (The New Natural History of Madagascar). I compare biodiversity information presented in the new book with data from the earlier book, providing insight into scientific advancements, and revised estimates of species richness and endemism of a range of taxonomic groups.
Sea-serpent sightings were popular subjects of nineteenth century fictional tales. One of the most famous sightings, the 1817 appearance in the harbor of Gloucester (Massachusetts), generated a report published by the Linnean Society of New England. In 1869, ED Cope introduced a new reptilian order, Pythonomorpha, comprising large Upper Cretaceous marine lizards (mosasaurs) that he thought rather well captured in historical depictions of sea-serpents. The name Pythonomorpha emphasized the many striking features that Cope found mosasaurs to share with snakes. Cope’s Pythonomorpha was resurrected in the late 1990s, as a clade including mosasaurs plus snakes. This was supported by the placement of mid-Cretaceous marine snakes with well-developed hindlimbs as evolutionarily intermediate between mosasauroids and snakes. Critics pointed to features indicating that those fossil snakes are instead evolutionarily advanced, which would imply that hindlimbs of these fossil snakes re-developed from rudiments such as occur in pythons. Recent molecular developmental studies confirmed that the embryonic limb bud of the python hindlimb conserves the genetic program to generate a complete limb.
This chapter assesses morphological characters proposed to support the Pythonomorph Hypothesis— a purported close relationship between snakes and mosasaurians. With an emphasis on early diverging (non-mosasaurid) mosasaurians and mosaurids, new morphological data (including from high-resolution CT) for well-preserved dolichosaurid and mosasaurid fossils are presented. Details of the skull and mandibles are interpreted as supporting the monophyly of Mosasauria as the proximal outgroup of Varanoidea, to the exclusion of snakes. However, mosasaurians do deviate from the typical varanoid condition in aspects of their infraorbital foramen, ventral part of the lacrimal and its relationship with the prefrontal, anterior ramus of the ectopterygoid and its contact with the maxilla and jugal, lack of plicidentine, and (at least in early diverging mosasaurians) anguinoidean tooth replacement. We consider most characters previously reported as supporting the Pythonomorph Hypothesis to be problematic, because of incomplete fossil preparation, artefacts of taphonomy, limited comparisons, misinterpretations of anatomy, incomplete taxon sampling, or inadequate character formulation and/or scoring.
Mosasaurian phylogenetics has been one of the most controversial topics in squamate systematics, with various studies and authors arguing in favor of a varanoid affinity (the Varanoid Hypothesis), a snake affinity (the Pythonomorph and Ophidiomorph Hypotheses) or only distant affinities to these lineages (the Stem-scleroglossan Hypothesis). We review the classification history of mosasaurians over the past two centuries, focusing on non-mosasaurid mosasaurians (dolichosaurs and aigialosaurs). A reappraisal is provided based on a new phylogenetic analysis. Our results clearly support the Varanoid Hypothesis. The Pythonomorph and Ophidiomorph Hypotheses are reviewed, and characters traditionally inferred to support these hypotheses are discussed and reinterpreted. Taxonomic sampling and fossil completeness likely play a major role—our (hopefully improved) phylogenetic hypothesis being based on denser taxon sampling and more complete character scoring resulting from additional studies, including the application of modern imaging techniques. Based on current data, our interpretation is that a particularly close phylogenetic relationship between mosasaurians and snakes can be rejected.
Pachyophiidae fossils are among the most complete known for snakes, and include the earliest snakes with fully developed hindlimbs. Pachyophiids have been historically seen as suitable morphological intermediates between lizards and extant snakes, supporting the hypothesis that snakes originated in a marine setting from a macrophagous common ancestor with mosasaurian lizards. Pachyophiids have been subject to conflicting interpretations of their anatomy, fuelling renewed debate on snake origins and early diversification. We revisit pachyophiid cranial anatomy, providing additional evidence from new preparations, high resolution CT scans, and Synchrotron images. We address challenges posed by fossil (in)completeness to the study and interpretation of these specimens, and reassess phylogenetic affinities. We critically reassess morphological evidence supporting the Marine Hypothesis, concluding that (i) snakes are not especially closely related to mosasaurians, and (ii) pachyophiids are relatively deeply nested within the snake crown, so that they are of greater importance for understanding early crown-snake evolutionary history than they are for understanding snake origins.
Autonomous vessels and robotics, artificial Intelligence and cybersecurity are transforming international shipping and naval operations. Likewise, blockchain offers new efficiencies for compliance with international shipping records, while renewable energy from currents and waves and offshore nuclear power stations open opportunities for new sources of power within and from the sea. These and other emerging technologies pose a challenge for the governance framework of the law of the sea, which is adapting to accommodate the accelerating rates of global change. This volume examines how the latest technological advances and marine sciences are reshaping the interpretation and application of the law of the sea. The authors explore the legality of new concepts for military operations on the continental shelf, suggest remote sensing methodologies for delimitation of maritime boundaries, and offer a legal roadmap for ensuring maritime cyber security.
Stingray envenomation is a marine injury suffered by ocean goers throughout the world. No prospective studies exist on the various outcomes associated with these injuries.
Study Objective:
The aim of this study was to perform a prospective, observational study of human stingray injuries to determine the natural history, acute and subacute complications, prevalence of medical evaluation, and categories of medical treatment.
Methods:
This study prospectively studied a population of subjects who were injured by stingrays at Seal Beach, California (USA) from July 2012 through September 2016 and did not immediately seek emergency department evaluation. Subjects described their initial injury and provided information on their symptoms, medical evaluations, and medical treatment for the injury at one week and one month after the injury. This information was reported as descriptive statistics.
Results:
A total of 393 participants were enrolled in the study; 313 (80%) of those completed the one-week follow-up interview and 279 (71%) participants completed both the one-week and one-month follow-up interviews. Overall, 234 (75%) injuries occurred to the foot. One hundred sixty-three (52%) patients had complete resolution of their pain within one week and 261 (94%) had either complete resolution or improvement of pain by one month. Sixty-eight (22%) subjects reported being evaluated by a physician and a total of 49 (17%) subjects reported antibiotic treatment for their wound. None of the subjects required parenteral antibiotics or hospital admission.
Conclusion:
The majority of stingray victims recover from stingray injury without requiring antibiotics. A subset of subjects will have on-going wound pain after one month. The need for parenteral antibiotics or hospital admission is rare.
Almost five million Americans volunteered to serve in the U.S. armed forces between 2001 and 2021 and returned home as discharged veterans. Among them, 30,177 men and women have taken their own lives, an awful toll that is more than five times the number of Americans killed in combat in our twenty-first century wars. As part of the roundtable, “Moral Injury, Trauma, and War,” this essay argues that the reasons are many, but one major factor may be the moral pain that many experience in wartime and the vast emptiness they often encounter when their military service ends. Our society has an obligation to the post–9/11 veterans to understand their experiences and truly welcome them back. The rising toll of veteran suicides suggests there is little time to lose.
Petroleum hydrocarbons (PH) toxicity and bioaccumulation in aquatic organisms have been investigated for almost 50 years. Continuous oil spillages necessitate a further understanding of the toxicological effects of PH on brachyuran crabs. Crabs can be exposed to PH through various routes such as the water column, sediment and diet. Numerous investigations have been dedicated to evaluating PH toxicity on different life stages of crab species, but the majority of them have focused on the blue crab Callinectes sapidus as it represents an edible and favourable seafood commodity for human consumption. The objective of the review is to critically assess studies related to PH toxicity on different life stages of 41 crab species representing 13 families across the world. Several physiological, biochemical and genetic endpoints of marine crabs were evaluated in addition to the sublethal effects of PH on crab metabolism, behaviour, moulting, growth and survival. A concise summary of PH deleterious effects on different taxonomic species of marine crabs is discussed and provides evidence that crabs can be used as indicator organisms of biomarker significance for marine pollution. Overall, larval stages appeared to be the most sensitive to the deleterious effects of PH compared with juveniles and adults. However, adult stages have received more research attention than other life stages, followed by larval stages, and juvenile stages are the least investigated stages with respect to PH toxicity. Finally, hepatopancreas and gills were the organs where greatest accumulation of PH was recorded.
On the continental shelf of the Antarctic the major disturbance to benthic ecosystems is from iceberg scouring; however, this is based on observations from the Peninsula region. We combine observation and experimentation in the McMurdo Sound region of the Ross Sea to determine if community recovery patterns there are similar to those in better-studied Antarctic regions, and if local immigration is an important factor in recovery dynamics. We found that regardless of habitat differences in depth, substrate, and oceanographic setting, iceberg disturbance strongly impacted benthic communities in McMurdo Sound. Notably, in shallow water (<30 m) where anchor ice is an annual disturbance, both the benthic communities and recovery processes were more variable than at deeper locations. A manipulative experiment performed in a shallow area indicated that recruitment might be more important than immigration to infaunal community recovery. We conclude that whilst disturbance frequency influences dominant epifauna, recovery from iceberg disturbance is a slow ecological progression that is dependent on the extremely inconsistent recruitment processes of the high Antarctic benthic ecosystem.
In this study we report a new record of a cryptogenic polychaete from southern Africa. The species was found inhabiting sand tubes in intertidal sand flats in the Knysna Estuary on the southern coast of South Africa. Morphological comparisons using light and scanning electron microscopy showed extensive taxonomic similarities with Dipolydora socialis described from other localities and from museum vouchers. In addition, 18S rRNA and COI barcodes were generated for the species. Genetic analysis of the assembled polydorid dataset corroborated the morphological data in delineating the species as a taxonomic unit with >99% genetic similarity to available sequences of D. socialis in the GenBank database. Dipolydora socialis has been reported as having a widespread distribution, and since it can reside within tubes associated with fouling communities or as a shell borer, several vectors may have been responsible for its global spread and introduction to southern Africa. Finally, considering the many cryptic complexes that are currently being uncovered within polychaetes, including spionids, future taxonomic studies should incorporate additional genetic data from other regions of the world to determine whether D. socialis may also be part of a larger species complex.
Shipping is responsible for transporting 90% of the world's trade. This book provides a comprehensive review of the impact shipping has on the environment. Topics covered include pollutant discharges such as atmospheric emissions, oil, chemical waste, sewage and biocides; as well as non-pollutant impacts including invasive species, wildlife collisions, noise, physical damage, and the environmental effects associated with shipwrecks and shipbreaking. The history of relevant international legislation is also covered. With chapters written by eminent international authors, this book provides a global perspective on the environmental impact of ships, making it a useful reference for advanced students and researchers of environmental science, as well as practitioners of maritime law and policy, and marine business.
Ocean warming and acidification are expected to influence the biology of the ecologically and economically important red king crab, Paralithodes camtschaticus. We investigated transcriptome responses of adult, larval and juvenile red king crab to assess sensitivity to reduced pH and elevated temperature. In adults, gill tissue (but not heart or cuticle) responded to reduced pH by differentially regulating many genes involved in metabolic, membrane and cuticular processes, but not ionic or acid/base regulation. In larval crabs, we found little evidence for a strong transcriptomic response to pH, but did observe large differences in the transcriptomes of newly hatched and one-week old larvae. In juvenile crabs, we found that there was a strong transcriptomic response to temperature across all pH conditions, but that only extreme low pH caused transcriptomic shifts. Most of the genes in juveniles that were differentially expressed were for cuticular and calcification processes. While inferences regarding the specific biological responses associated with changes in gene expression are likely to change as resources for red king crab genomics enabled studies continue to improve (i.e. better assemblies and annotation), our inferences about general sensitivities to temperature and pH across the life stages of red king crab are robust and unlikely to shift. Overall, our data suggest that red king crab are more sensitive to warming than acidification, and that responses to acidification at the transcriptomic level occur at different levels of pH across life stages, with juveniles being less pH sensitive than adults.
Usage of composite materials is ubiquitous in the modern world. While global tonnages are still well below those of steel, they now find a wider range of applications and their value is starting to become comparable to that of steel products. As low weight and energy efficiency become increasingly important, this trend is likely to accelerate. In this chapter, the objective is to identify some of the issues involved in commercial exploitation of composites. This is done by means of case studies drawn from various industrial sectors. The examples cover a range of composite type, engineering complexity, manufacturing route, market size and competitive position relative to more traditional materials.
Radioactive Waste Management Limited (RWM) is tasked with implementing geological disposal of the United Kingdom's (UK) higher activity radioactive wastes. This paper describes how RWM's biosphere modelling capability has been extended from a solely terrestrial model to allow potential contaminant releases to estuarine, coastal and marine systems around the UK to be represented. The new models aim to strike a balance between being as simple as can be justified, erring on the side of conservative estimates of potential doses, while also representing the features and processes required to reflect and distinguish UK coastal systems. Sediment dynamics (including meandering of estuaries and sediment accumulation) are explicitly represented in a simplified form that captures the accumulation and remobilization of radionuclides. Long-term transitions between biosphere systems (such as from a salt marsh to a terrestrial system) are outside the scope of the study. The models and supporting data draw on information about the UK that is representative of present-day conditions and represent potential exposures arising from both occupational and recreational habits.?
Generic calculations demonstrate that potential doses to humans arising from releases to estuarine, coastal and marine systems are typically more than two orders of magnitude lower than those for equivalent releases to terrestrial systems via well water and groundwater discharge to soil. The extended capability (i) ensures that RWM is able to undertake assessments for potential coastal site contexts, if and when required, and (ii) provides RWM with quantitative evidence to support the principal focus on terrestrial releases ( particularly for more generic assessments).