Marine Wildlife Research Articles

The influence of human and marine wildlife presence on white shark behaviour in nearshore areas

Abstract The co-occurrence of people and sharks within nearshore areas raises concerns about human safety. Unprovoked shark bites are one of the most renowned negative human–wildlife encounters. White sharks (Carcharodon carcharias) are implicated in most fatal unprovoked shark bites globally, but there is limited knowledge of white shark behaviour in the presence of people. We used drone-based methods to analyse human–shark and wildlife–shark interactions. We found a higher probability of a white shark interaction with a nearby person (0.81) in comparison to an animal (0.65). Fishers had the highest, and swimmers had the lowest probability of a white shark interaction. White sharks exhibited investigative behaviour in most interactions, with directional changes towards a nearby person or animal in 85.9% and 94.0% of interactions, respectively. There was a higher probability for white sharks to increase their speed towards animals (0.16) than people (0.01). The likelihood of white sharks altering their speed or direction when people were present depended on human activity. Overall, our study highlighted the value of drone technology in providing insights into white shark behaviour. It also supported the contention that, while people and white sharks coexist within nearshore areas, the probability of a negative human–wildlife encounter remains low.

Emergence of black spot syndrome in Caribbean reefs: a century of fish collections reveal long-term increases in Scaphanocephalus infection.

Despite evidence that certain diseases of marine wildlife are increasing, long-term infection data are often lacking. Archived samples of hosts from natural history collections offer a powerful tool for evaluating temporal changes in parasitism. Using vouchered fish collections from the Southern Caribbean, we investigated long-term (1905-2022) shifts in infections by the trematode Scaphanocephalus spp., which causes black spot syndrome (BSS) in reef fishes. Examination of 190 museum-preserved fishes from Curaçao and Bonaire revealed that Scaphanocephalus infections are not new, with histologically confirmed detections from as early as 1948. However, Scaphanocephalus was rare among archival surgeonfish and parrotfishes, with an infection prevalence of <10% and an average abundance of 0.25 metacercariae per fish. Contemporary collections of 258 ocean surgeonfish and parrotfishes (7 species) supported a 7-fold higher prevalence (71%) and a 49-fold higher abundance (12.1). These findings offer evidence that infections by Scaphanocephalus spp. have increased substantially over the past century and underscore the value of biological repositories in the study of emerging parasites within marine ecosystems. We emphasize the need for additional research to evaluate the geographical extent of BSS emergence, test proposed hypotheses related to shifts in host density or environmental characteristics and assess the consequences for affected species.

Sharing the ocean: fostering blue synergies for sustainable whale-watching

Whale-based tourism activities offer unique opportunities for humans to observe cetaceans in their natural habitats. Well-planned experiences can provide educational value and promote respectful enjoyment of marine wildlife. Conversely, poorly managed activities can negatively impact cetaceans by injuring or killing them (through collisions with boats) or altering their behavior, such as resting time, nursing or diving. This study presents an example of designing and implementing a whale-based tourism activity in the Canary Islands (Spain), with the participation of researchers, whale-watching operators and tour guides, public policy-makers, and civil society, with a strong focus on educational values. The coastal communities are crucial in promoting sustainable whale-watching practices through educational initiatives, community engagement, and stakeholder collaboration. The paper employs a process-monitoring approach to evaluate the whole procedure of whale-watching activity implementation. We assume that the success of any tourism activity depends on the process that leads to its creation. The analysis emphasizes the need for careful planning and execution to design and implement marine tourism experiences. Concerns for tourism satisfaction and safety and the need for environmental sustainability challenge the management of whale-watching operations. In this regard, engaging local communities, addressing safety and conservation concerns, and promoting responsible tourism practices are essential for mitigating these challenges and ensuring the long-term viability of whale watching as a sustainable and educational activity.

Importance–Performance Analysis of the Sustainability of South Penghu Marine National Park, Taiwan

Despite the growing global focus on marine protected areas, there is a dearth of research addressing the comprehensive sustainability of such areas. This study fills the gap by evaluating the sustainability of South Penghu Marine National Park (SPMNP) using importance–performance analysis (IPA) across 18 sustainability indicators, encompassing environmental, economic, and social dimensions. The results reveal that environmental sustainability was rated as the most critical, with top indicators including protecting ecological habitats and marine wildlife. Performance scores were generally satisfactory, though disparities between importance and performance were noted, suggesting areas for improvement. Notably, all sustainability indicators are significantly below the threshold performance target of 75%, indicating significant gaps in meeting public expectations. The analysis also highlights strong public support for both on-site and off-site management measures as key strategies to enhance park sustainability. This study provides valuable insights for policymakers and park managers aiming to improve the sustainability of marine protected areas.

An appropriate artificial intelligence technique for plastic materials recycling using bipolar dual hesitant fuzzy set

Plastic recycling has become more important than ever as the globe struggles with growing environmental issues. This research explores the significant environmental impact of recycling plastic and its growing relevance. The pervasive material known as plastic presents a complex risk to both human health and ecosystems in contemporary life. It exacerbates problems including marine pollution, habitat damage, and wildlife entanglement because of its persistence in landfills and seas, which leads to serious ecological deterioration. In addition, producing plastic uses a lot of energy and produces a lot of greenhouse gas emissions, which exacerbate climate change. Through the use of multi-criteria decision making (MCDM), this study emphasizes how vital it is to support recycling activities in order to protect the environment and promote a sustainable future. The elimination and choice ex-pressing reality (ELECTRE) approach is used to rank the alternatives in this proposed research study that employs bipolar dual hesitant fuzzy sets (BDHFs). The most efficient and versatile outranking method for making decisions is the BDHF-ELECTRE approach. The weights of environment, economic, social, technical, and finally safety is computed using the entropy distance metric. The economic factor received the highest score of 0.2945 among the other factors since economic considerations are crucial in choosing the most efficient plastic recycling method, as they ensure sustainability, cost-effectiveness, resource allocation, and overall feasibility in managing plastic waste. The decision-makers determined that the mechanical recycling approach ought to be prioritized over all others for the efficient recycling of plastic waste. The robustness of the system is examined in the sensitive and comparative analyses. The proposed MCDM technique thus presents a viable solution, mitigating the adverse effects of plastic waste by conserving resources, reducing energy consumption, and curbing pollution.

Acoustic telemetry suggests the lesser spotted dogfish Scyliorhinus canicula stays and uses habitats within a French offshore wind farm

Offshore wind farms (OWF) are a rapidly expanding renewable energy source, but their effects on marine wildlife need further investigation. These infrastructures form new artificial habitats that may modify the behaviour and spatial distribution of fish species. Among the species likely to be affected, benthic sharks occupying coastal habitats are particularly exposed to the development of OWF, especially as electrosensitive species. This study used passive acoustic telemetry to investigate the behaviour of a benthic shark, the lesser-spotted dogfish Scyliorhinus canicula, within France's first operational OWF. Most tagged sharks remained in the vicinity of the OWF post-release, exhibiting site fidelity and seasonal residency with reduced presence during winter when water temperatures are the lowest. The primary site frequented is a monopile with scour protection on soft substrate, offering potential shelters and food sources. This study provides new insights into the species' ecology and contributes to improving our understanding of how anthropogenic structure installation in the marine environment affects the behaviour of S. canicula.

Assessment of the effectiveness of ship machinery noise reduction measures using a test platform in a water basin

Underwater radiated noise (URN) from commercial shipping is partly responsible for increased ocean ambient noise levels in the last decades. To preserve marine wildlife, there is a need to reduce it. Machinery noise is the dominant URN source at lower speeds. Mitigation technologies exist to reduce it, but a lack of quantitative data regarding their effectiveness results in limited practical ship applications since the cost-to-benefit ratio is imprecise. A small ship-like structure (test platform) representative of a ship section is designed and constructed to conduct measurements in a controlled environment and at a lower cost than actual on-ship testing. The platform is deployed in a water basin whose acoustic response is first characterized by reverberation measurements. Vibroacoustic sources simulate structure-borne and airborne noise, while hydrophones and sensors measure the response in the water basin and of the platform. Measurements with and without standard mitigation technologies installed in the platform are conducted to quantify the insertion loss. Up to 37 and 20 dB URN reductions are obtained with elastic mounts and mineral wool, respectively. The results obtained with the platform and the developed methodology can support and guide the implementation of mitigation measures in current and future ship constructions.

Plastic pollution on beaches in an Antillean manatee conservation area, Brazil

The presence of plastic debris along shorelines is a widespread problem, and plastic debris can interact directly with marine wildlife. In northeast Brazil, the Antillean manatees are the most common marine mammals and use estuarine waters mainly as their home range. We aimed to investigate the characteristics of plastic debris on the estuarine-oceanic continuum and the accumulation density of plastic on beaches. The density of plastic debris on beaches located in transitional areas was 7–10-fold greater than that on beaches in estuarine and oceanic areas. Fragments were considered the most abundant form of plastic debris on all the beaches. Our findings could lead to improved pollution management in this marine protected area, principally due to the risks of remobilizing small plastic particles through tides and wind effects that scatter them in resting and feeding manatees areas.

A quantitative assessment of continuous versus structured methods for the detection of marine mammals and seabirds via opportunistic shipboard surveys

Marine monitoring efforts are increasingly supported by opportunistic shipboard surveys. However, opportunistic survey methods often require adaptation to suit the vessel and the operations being conducted onboard. Whilst best-practice techniques for surveying marine wildlife on vessels of opportunity are yet to be established, testing and development of alternative methods can provide means for capturing ecological information in otherwise under-surveyed areas. Explicitly, survey methods can be improved while baseline ecological data for new regions are gathered simultaneously. Herein, we tested different survey approaches on a vessel of opportunity in a remote offshore area where little is known about the community composition of top-order marine vertebrate predators: western and south-western Tasmania, Australia. We found that continuous surveys provide greater species counts than structured “snapshot” surveys over the course of a voyage, but that structured surveys can be more practical when managing factors such as observer fatigue. Moreover, we provide a baseline dataset on the marine vertebrate community encountered in western and south-western Tasmania. This information will be critically important for industry and conservation management objectives, and is key to our understanding of the offshore ecosystem around Tasmania.

Passive citizen science: social media as a tool for marine wildlife observation

It is not new that species occurrence records provided by citizens are valuable contributions to marine research. However, passive citizen science is a recent and promising methodology of crowdsourcing. Here, we review existing studies that used spontaneous posts shared by users on social media to obtain marine wildlife scientific data. We also present a critical analysis of passive citizen science using social media. Specifically, we (1) introduce marine citizen science and (2) analyze the advantages of passive citizen science compared with voluntary approaches. We also (3) present investigations that extracted information and produced knowledge for marine ecology and conservation through passive citizen science, (4) discuss best practices and opportunities, and (5) identify challenges of this approach. Although social media data may have inherent biases and diverse ethical issues, the data volume is generally large, and the benefits of obtaining observations at a low cost and in real time compensate for some shortcomings, which can sometimes be mitigated. Considering that the use of passive citizen science will continue to grow and be part of our daily lives, we expect the current review to be useful for future investigations.

Subnational governments and non-state actors in environmental governance: Japan, Russia, and the Northern fur seal

Russia's invasion of Ukraine in 2022 put to test the North Pacific regional governance structure, with environmental cooperation overshadowed by security concerns. In this paper, the central government, subnational and non-state actors' potential in finding ways out of environmental governance crises is explored. The authors turn for possible clues to the Northern fur seal conservation and management regimes, which existed in 1911–40 and 1957–84 and laid the groundwork for marine wildlife conservation and management in the North Pacific, in the century replete with military conflicts and international tension. The focus is on Japan and Russia's subnational and non-state actors (private companies, experts, NGOs and indigenous communities), who have received much less attention than their US and Canadian counterparts. Their roles in negotiation, operation and dismantlement of these regimes, are analyzed in domestic and international contexts by applying Putnam's “two-level game” metaphor. Their motives and tactics, interconnections and clout are examined in the light of both states' domestic and foreign policy goals and constraints, and regional and global trends in environmental governance. The recent multi-actor undertakings for marine mammal conservation and management in Japan and Russia are also explored from the multilevel governance perspective. It is hoped that the current diplomatic deadlock may be overcome by utilizing sub-state and supra-state frameworks and channels for communication.

Management of Plastic Wastes through Recent Advanced Pyrolysis Processes

Plastics are predominant in numerous sectors like packaging, agriculture, hardware, electronics, and many others. Annual plastic demand has been rapidly growing in the last few decades because of the increasing dependency on plastics. As a consequence, massive amounts of plastic waste are being generated every year. These plastic wastes are non-biodegradable, and hence their disposal poses a serious threat to the ecosystem and causes significant environmental problems such as endangering the safety of marine life, wildlife, air, water, and soil, etc. A large portion of plastic waste ends up in landfills, and only a small fraction is recycled. The continuous dependence on landfills as the main disposal method for plastic waste is costly and ineffective. Common solutions to plastic waste management are incineration and recycling; however, incineration emits harmful pollutants and greenhouse gases that contribute to ozone layer depletion and global warming; moreover, recycling is expensive and inefficient. As an alternative to recycling and incineration, the pyrolysis process can convert plastic wastes into more valuable fuel products. Pyrolysis is a thermal process that converts raw material into pyrolysis liquid, solid wax, and non-condensable gases in the absence of oxygen. This process is attractive because it is economical and energy-efficient, and it can be used to convert various types of plastic waste into valuable products. In recent years, there have been significant developments in pyrolysis applications in liquid fuel production from plastic wastes. This work reviews recent advances in and challenges for the pyrolysis process for converting plastic wastes into a valuable alternative fuel, focusing on studies of advanced pyrolysis processes published over the last five years. The paper also highlights the numerical modeling of pyrolysis of plastic wastes and the potential impact of pyrolysis on the future of sustainable waste-management practices of plastics.

Strong site fidelity, residency and local behaviour of Atlantic cod (Gadus morhua) at two types of artificial reefs in an offshore wind farm.

Globally, biogenic temperate reefs are among the most threatened habitats. In the North Sea in particular, large shellfish reefs were lost owing to fishing activities in the 1900s. The impact of offshore wind farms (OWFs) on marine wildlife is extensive, and it offers the possibility to reintroduce new hard substrate habitats that are protected from fisheries at a large scale. In addition to the submerged structures of OWFs, marine hard substrate habitat can be further enhanced by providing extra artificial reefs. In an operational OWF along the Dutch coast, four artificial reefs (two with a scour bed and two without) were deployed in the vicinity of a wind turbine. Acoustic telemetry was used to monitor the fine-scale movement of 64 Atlantic cod (Gadus morhua). The monitoring ran from July 2021 to January 2023. Detailed information on behaviour, area utilization and attraction to the structures was determined. Results showed strong attraction (high site fidelity and residency) to the artificial reef, with no significant difference between the two tested types of reefs, and only a few individuals staying over winter. Cod spent a large proportion of their time hiding in the artificial reefs, suggesting that adding pipes for shelter has a beneficiary effect.

Overlapping use of areas in a marine wildlife reserve on the northeastern coast of Brazil

En muchas áreas marinas protegidas de Brasil, el turismo ocurre sin planificación, como en la Reserva de Fauna Costera de Tibau do Sul (REFAUTS). En REFAUTS, los turistas utilizan el área de dos pequeñas bahías para realizar diferentes actividades y compartir espacio con delfines. Por lo tanto, el objetivo de este estudio fue caracterizar el flujo turístico en REFAUTS e identificar cuáles áreas son las más frecuentadas por los turistas. Se midió el flujo turístico en REFAUTS por medio de una encuesta realizada entre las 9:00 a. m. y las 4:00 p. m., y se identificaron las zonas más utilizadas por los turistas. REFAUTS recibe a más de 1.400 visitantes por día, la mayoría entre las 11:00 a. m. y las 3:00 p. m., lo que corresponde al tiempo activo del delfín en las bahías. En una misma zona se practican diferentes actividades, como surf, kayak, stand-up paddle, baño y avistamiento de delfines; esta superposición puede generar conflictos socioambientales y efectos negativos sobre los delfines. Se recomienda un plan de zonificación para determinar cuáles áreas deben ser utilizadas por los turistas y establecer áreas exclusivas para delfines.

Abandoned, Lost and Otherwise Discarded Fishing Gear in the Eastern Caribbean: Barriers, Challenges, and Opportunities for Improved Governance

Abstract In recent years there has been a growing focus on filling critical knowledge gaps on the challenge of abandoned, lost, and discarded fishing gear (ALDFG) in the global ocean. While not the biggest contributor to the world’s marine debris problem, ALDFG has been shown to be a particularly deadly form of marine litter due to its ability to entangle, entrap, and ensnare marine wildlife, damage coastal habitats, and result in negative economic impacts to the fishing sector. In the Eastern Caribbean region, fisheries play a crucial role in ensuring livelihood and food security for vulnerable coastal communities. Therefore effective management interventions that are geared towards eliminating anthropogenic threats to the marine environment, including ALDFG are considered of paramount importance. This article aims to gain insight into challenges associated with the governance of ALDFG within the small-scale fisheries of the Eastern Caribbean with a view to outlining opportunities for improvement. A qualitative approach was utilized and interviews were conducted with fisheries and conservation experts from both national and regional-level institutions. The participants revealed that ALDFG was of significant concern for their country or the region and each advocated for the establishment of improved management infrastructure. Identified barriers that could impede this critical goal include limited human and financial capacity, lack of knowledge and understanding of ALDFG generally, lack of trust, and policy incoherence across sectors and between regional and national agencies. To overcome barriers, a multi-faceted approach is required, including regulatory and institutional improvements.

The need for interdisciplinary research in marine sciences – A MERry outlook

The global oceans are facing a plethora of pressures, leading to cross-national impacts on marine ecosystems, wildlife, and resource users. Interdisciplinarity is integrating knowledge and methods from different disciplines to generate a comprehensive output. Due to the trans-boundary nature of marine habitats and stressors, interdisciplinary research forms the basis to addressing pressing matters in ocean health and conservation. To this end, the Marine Environment and Resources (MER) master programme was developed at the beginning of the century, enabling students to develop a well-rounded understanding of ocean science. The programme has since become a recognised Erasmus Mundus degree and has had almost 400 graduates. In September 2022, the first MER community summit was held, being a landmark for the building of a long-lasting global community to discuss and deal with priority challenges of the UN Decade of Oceans Science. This summit has highlighted that to understand the state of the oceans and improve conservation efforts, international collaboration is required (including those out with the academic realm). The following article aims to highlight the successes of the programme in aiding the development and training of interdisciplinary researchers from a plethora of backgrounds, uniquely suitable for addressing current problems.

Remote sensing and machine learning to improve aerial wildlife population surveys

Technological and methodological advances in remote sensing and machine learning have created new opportunities for advancing wildlife surveys. We assembled a Community of Practice (CoP) to capitalize on these developments to explore improvements to the efficiency and effectiveness of aerial wildlife monitoring from a management perspective. The core objective of the CoP is to organize the development and testing of remote sensing and machine learning methods to improve aerial wildlife population surveys that support management decisions. Beginning in 2020, the CoP collaboratively identified the natural resource management decisions that are informed by wildlife survey data with a focus on waterbirds and marine wildlife. We surveyed our membership to establish 1) what management decisions they were using wildlife count data to inform; 2) how these count data were collected prior to the advent of remote sensing/machine learning methods; 3) the impetus for transitioning to a remote sensing/machine learning methodological framework; and 4) the challenges practitioners face in transitioning to this framework. This paper documents these findings and identifies research priorities for moving toward operational remote sensing-based wildlife surveys in service of wildlife management.

Spatial planning offshore wind energy farms in California for mediating fisheries and wildlife conservation impacts

Achieving a blue economy will require reconciling the value of emerging ocean uses with their impacts on the seascape and sectors with historical access to marine resources and areas. To meet this challenge, we developed an analytical framework for conducting marine spatial planning through tradeoff analysis, and applied it to prospective offshore wind energy development in the ∼974 km2 Morro Bay, California, USA Wind Energy Area (WEA). We generated spatial data layers estimating MW power production and impacts on fisheries value and marine wildlife conservation (seabird and cetacean populations) from wind farm development. We then quantified each sector's response to plans of development across the WEA and inside three leases recently acquired by the energy industry for prospective development. Finally, we integrated the sector response data into an analytical framework for mitigating sector tradeoffs with novel spatial planning solutions (maps of wind farm size, location, and configuration) that optimally maximize value to the emergent energy sector (MW power) while minimizing impacts to historical (fisheries and wildlife) sectors. We found that western sites in the WEA had the highest potential power production concurrent with the lowest impact on the historical sectors, revealing the eastern lease to be less efficient at optimally balancing the sector's objectives relative to the development of the central or western leases or the optimal spatial plans identified in the tradeoff analysis. Within a lease, tradeoff analysis found spatial planning able to generate out-sized savings in fisheries value with only modest losses in MW power – for example, by avoiding development in just 5% of the eastern lease to preserve nearly half its fisheries value and still generate 95% its total power potential. Small-scale development opportunities (e.g., a pilot project) with significant power potential and no fisheries impact were also identified, in this case by placing turbines in an area in the western lease with no fisheries value and high power production potential. These plans would also have a relatively low impact on the wildlife conservation sectors, due to decreases in vulnerability levels of both seabird and cetacean populations to turbines going from east to west across the WEA. Our results can inform site evaluation and permitting processes for wind energy development in the Morro Bay WEA. We also expect the tradeoff analysis framework we developed to provide a simple and actionable analytical tool for supporting marine spatial planning of offshore wind energy and other emerging blue economy activities from a balanced perspective that values emerging uses of marine resources alongside existing socio-economic and conservation interests.

Shark Fin City: transitional marine wildlife economies in Global Hong Kong

ABSTRACT Hong Kong has historically been the epicenter of the global shark fin trade. Despite this legacy, recent public outreach campaigns highlighting the effects of consumption on marine ecosystems have precipitated shifts in the market. Fish maw and sea cucumber have emerged as substitutes in wildlife markets, marking an understudied phenomenon from urban geographical perspectives. This article investigates the transitional nature of social value systems underpinning Hong Kong's marine wildlife market through interviews with retailers, conservation organizations, and government officials, as well as visual surveys of market displays. Hong Kong's marine wildlife market, this article contends, brings into sharp relief how transitions in social value systems that substitute one type of non-fungible wildlife commodity for others can amplify biodiversity loss and reproduce expressions of social difference in urban space. The article illuminates how social value systems embedded in urban wildlife markets are related to human health, aging, gifting, and relationship building. Furthermore, it analyzes how the possession, consumption, and display of high-value wildlife commodities in cities reflects classed and gendered forms of social difference. The article further examines the challenges of regulating the market and shaping public values and actions in the face of escalating global biodiversity loss.

Predicting whaler shark presence and interactions with humans in southern Queensland, Australia

The Queensland Shark Control Program (QSCP) started in 1962 to reduce the number of shark-human incidents by deploying nets and drumlines across the most popular beaches. The program targets large shark species (white, tiger and bull sharks) that are potentially hazardous to bathers. However, this strategy is lethal for other sharks and marine wildlife, including threatened and endangered species. Thus, finding non-lethal strategies is a priority. To better manage shark-human interactions, establishing a better understanding of the factors that drive shark movement is key. Here we used sea surface temperature (SST), rainfall and distance to rivers as environmental variables to predict the presence of whaler sharks in southern Queensland based on 26 years of catch data from the QSCP. We found that SST is positively corelated to sharks caught by drumlines, while rainfall was associated with the number of sharks captured in shark nets. In addition, more sharks were captured by nets and drumlines further away from rivers, and nets captured roughly 10 times more sharks than drumlines over the period of study. In contrast to tiger sharks, the catch data indicate the number of whalers has not declined over the past 26 years. Our findings suggest that environmental variables can be used to predict the movement of large sharks and by incorporating this knowledge into management plans and public education programs, may ultimately reduce shark-human incidents.