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Marine protected areas miss key habitats of Bryde's whales and bottlenose dolphins exposed to anthropogenic stressors
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After the near-complete cessation of commercial whaling, ship collisions have emerged as a primary threat to large whales, but knowledge of collision risk is lacking across most of the world's oceans. We compiled a dataset of 435,000 whale locations to generate global distribution models for four globally ranging species. We then combined >35 billion positions from 176,000 ships to produce a global estimate of whale-ship collision risk. Shipping occurs across 92% of whale ranges, and <7% of risk hotspots contain management strategies to reduce collisions. Full coverage of hotspots could be achieved by expanding management over only 2.6% of the ocean's surface. These inferences support the continued recovery of large whales against the backdrop of a rapidly growing shipping industry.
Global, regional, and national targets have been set to protect and conserve at least 30 % of the ocean by 2030, in recognition of the important benefits of healthy ocean ecosystems, including for human well-being. Many of these targets recognize the importance of the quality, not just quantity, of areas that are included in the 30 %, such as marine protected areas (MPAs). For example, the Convention on Biological Diversity's Global Biodiversity Framework Target 3 calls for areas to be effectively conserved and managed, ecologically representative, well-connected, and equitably governed. Protecting a percent area is not the sole goal-protection must be effective and equitable. To better understand the quality of biodiversity conservation afforded, in addition to the quantity of area protected, we looked at MPAs across 13 studies that used The MPA Guide and related tools to track Stage of Establishment and Level of Protection as measures of expected biodiversity conservation outcomes across diverse locations, scales, and cultural, political, and conservation contexts. We show that standardized assessments of MPA quality can help to (1) evaluate and improve existing MPAs; (2) plan new MPAs; (3) compare the quality of MPA protection across various scales; (4) track MPA quality, including progress towards coverage targets; (5) enable clear communication and collaboration, and (6) inform actions needed to achieve policy targets and their underlying environmental and social goals, among others. We share common opportunities,
Despite the importance of coastal habitats for the provision of many ecosystem services, these areas are currently among the most impacted by human activities. Impacts on coastal ecosystems may affect many key species, such as the Guiana dolphin, which inhabits Sepetiba Bay in south‐eastern Brazil, a highly degraded environment owing to a human‐induced rapid environmental change.
In this context, this study investigates the potential changes in the local Guiana dolphin behaviour, group structure, bioacoustics, site fidelity and habitat use over the past 20 years.
For this, a historical database (1998–2007) was compared with current data on the local dolphin population (2017–2019).
Between 2017 and 2019, the Guiana dolphins form significantly smaller groups ( W = 3262.5, P > 0.001), spend more time foraging (61 vs. 10% in the past), emit whistles at a considerably lower rate (decreasing by 85.2%), have reduced site fidelity and now use a larger area.
As Sepetiba Bay has been severely impacted by human activities in the recent past, with profound consequences for much of its biodiversity, the observed changes in dolphin behaviour are probably a consequence of habitat degradation and, in particular, of reduced prey availability. These findings have important implications for the management and conservation of the Guiana dolphin population of Sepetiba Bay.
To break this human‐induced rapid environmental change, it will be essential to minimize the spatio‐temporal overlap of anthropogenic impacts, to avoid cumulative impacts. To mitigate anthropogenic impacts on the Guiana dolphins of Sepetiba Bay, it will be important to direct the following actions: (i) the regulation and control of anthropogenic noise; (ii) reduction and control of the release of chemical contaminants and organic effluents; (iii) more effective controls on vessel traffic within the areas used preferentially by the Guiana dolphin; and (iv) the implementation of measures to avoid overfishing and bycatch.
Global reductions in the underwater radiated noise levels from cargo vessels are needed to reduce increasing cumulative impacts to marine wildlife. We use a vessel exposure simulation model to examine how reducing vessel source levels through slowdowns and technological modifications can lessen impacts on marine mammals. We show that the area exposed to ship noise reduces markedly with moderate source-level reductions that can be readily achieved with small reductions in speed. Moreover, slowdowns reduce all impacts to marine mammals despite the longer time that a slower vessel takes to pass an animal. We conclude that cumulative noise impacts from the global fleet can be reduced immediately by slowdowns. This solution requires no modification to ships and is scalable from local speed reductions in sensitive areas to ocean basins. Speed reductions can be supplemented by routing vessels away from critical habitats and by technological modifications to reduce vessel noise.
Bryde's whale (Balaenoptera brydei) is the only non-migratory (resident) baleen whale in Brazil, remaining year-round in the subtropical seas, but are among the least known whales. By combining genetics and spatial analysis, we aim to characterize the genetic diversity and determine the spatiotemporal distribution and habitat-use patterns for the Bryde's whale population in the South Brazil Bight, in the Santos Basin (23°S to 28°S/40°W to 49°W). During surveys (n = 16) between 2015 and 2018, we recorded 82 Bryde's whale groups and collected biopsy samples from 13 individuals. Based on our samples, the population of Bryde's whales presented low genetic diversity. Its distribution varied seasonally, with records occurring mainly in the north of the study area, near Cabo Frio, during warm seasons and in southern waters during cold seasons. The oceanographic dynamics, characterized by diverse frontal systems that enhance productivity on the shelf, likely drive the distribution of the whales, and the seasonal shifts between core areas seem to reflect changes in productivity and prey availability. Our results bring unprecedented information to understand the ecology of Bryde's whales on the Brazilian coast, and how their distribution and habitats are critically linked with the South Brazil Bight marine environment and its dynamics.
Underwater noise from human activities is recognized as a world-wide problem, with important repercussions on the acoustic communication of aquatic mammals. During the COVID-19 pandemic, the government of Panama went into a nationwide lockdown to limit the spread of the virus. This lockdown resulted in the closing of tourism infrastructure and limited mobility in both land and coastal areas. We used this “natural experiment” as an opportunity to study the impact of tour-boat activities on dolphin communication by using passive acoustic monitoring data collected before and during the lockdown at Dolphin Bay, Bocas del Toro, Panama. During the lockdown, tour-boat activity was absent, but boats transporting people and supplies were allowed to circulate. The shift in type of boat activity within the lockdown resulted in lower ambient noise levels and more frequent detections of dolphin sounds. We also detected a more diverse whistle repertoire during the lockdown than in the pre-lockdown period, even when accounting for variation in sample coverage. A Random Forest Analysis classified whistles between the two periods with high accuracy (92.4% accuracy, κ = 0.85) based primarily on whistle modulation and duration. During the lockdown, whistles were longer in duration and less modulated than pre-lockdown. Our study shows that a shift in boat traffic activity can generate significant changes in dolphin habitat, and in their communicative signals, an important consideration given ongoing unregulated ecotourism in the region.
Understanding the processes that determine the occurrence of species, especially for those exposed to human activities, is key to appropriate management. The common bottlenose dolphins, Tursiops truncatus, is well studied worldwide, but very little attention has been given to transient groups of this species and how such groups are exposed to human activities. Here, we modeled and mapped how the environment and human activities drives bottlenose dolphin habitat suitability, and residence patterns in an anthropized area of the Southwestern Atlantic Ocean. To predict habitat suitability, we ran 300 distribution models, including six algorithms, and generated an ensemble model. In parallel, we used photo-identification techniques to investigate dolphins' residence patterns. Our results demonstrated that primary productivity, seabed slope and port activities explained dolphins' habitat suitability. The most suitable areas included coastal waters, nearby port complexes and shipping routes. We also identified a low degree of residence in Cabo Frio and Rio de Janeiro city waters, but calves were constantly sighted there, indicating an important area for caring and nursing. The high overlap between the dolphins' most suitable areas and human activities, such as ports, vessel traffic and fisheries spots, plus the presence of calves in these areas, highlights the need for safeguard measurements to protect these animals from anthropogenic threats. Our results can be used to support management decisions, such as fisheries regulations and the creation of new marine protected areas to conserve critical habitats for this species.
The number and variety of technologies used for environmental surveillance is expanding rapidly, making constant data collection and near ‘real time’ analyses possible. ‘Smart Earth’ describes networked infrastructures comprised of devices and equipment and signals to the human dimensions inherent to developing, deploying and putting technology and large datasets to use. In this paper, we situate Smart Earth in terms of technological products and human practices and consider the relationship between Smart Earth and global environmental governance. Specifically, we review emerging literature and present a case study of an organization founded by environmental non-profit, SkyTruth, tech industry behemoth, Google and marine conservation NGO, Oceana. Called ‘Global Fishing Watch’ (GFW), this organization builds geospatial datasets, hosts an online mapping platform where anyone with internet access can surveil various types of ocean-going vessels and shares data and map products with scientists and practitioners. Two critical points emerge through the case. First, we show that GFW expands its surveillance capacity by pursuing ‘data sharing’ partnerships with sovereign states, many in the Global South. Second, the maps and datasets produced by GFW link vessels to a ‘flag state’ while the firms, subsidiaries and financiers that may own and/or operate these vessels remain obscure – and hence so too does the political economy of oceans fisheries. GFW maps and datasets offer new approaches to tracking fishing and are advancing fisheries science. At the same time, they rely on and are only legible through hegemonic geopolitical and political–economic orders deeply implicated in industrial (over)fishing. The norms and domains of global environmental governance are expanding, but Smart Earth ‘solutions’ risk leaving the structural drivers of environmental change unaddressed.
Recent changes in the South African marine ecosystem and the introduction of an experimental octopus fishery have resulted in an unsustainably high rate of fatal Bryde's whale entanglements. Using suction-cup attached bio-loggers, we identified a previously undescribed feeding behavior used by Bryde's whales to catch prey, and this behavior may make them susceptible to entanglement and mortality in bottom-mounted fishing gear. As they chase down their prey, inshore Bryde's whales sprint and maneuver along the seafloor for extended periods of time, making multiple direction changes, and reaching extraordinarily high swimming speeds. These findings assisted in the implementation of mandatory changes to octopus fishing gear that have drastically reduced the number of entanglements. The novel finding that Bryde's whales use high-speed chases near the seafloor to catch their prey highlights the value of using species-specific, behavioral information for making conservation recommendations
Small cetaceans (dolphins, porpoises, and small toothed whales) occur from the poles to the tropics, and from freshwater habitats to the open ocean. Most ecological research has focused on the influence of abiotic factors on the abundance, distribution, and behavior of these species. The ecological impacts of small cetaceans on communities and ecosystems remain poorly quantified. Their movement patterns, often high local and regional abundances across a range of ecosystems, and high metabolic rates suggest that small cetaceans could have large effects on ecosystem structure, dynamics, and function through a variety of mechanisms. These include top-down (e.g., direct predation and risk effects) and bottom-up effects (e.g., translocation of nutrients within and across ecosystems), but also behavior-mediated processes where these predators can facilitate access to resources to other predators or modify the physical properties of habitat (e.g., bioturbation). Most small cetaceans can be consumed by other marine predators, particularly killer whales (Orcinus orca) and large sharks. Although consumption rates of small cetaceans can be high, there is a paucity of information on their effects on population sizes or behaviors of their prey. Mass-balance ecosystem models suggest that small cetaceans may impact the populations of short-lived prey species (particularly fish and cephalopods), but other factors (e.g., eutrophication and fisheries) also affect ecosystem functioning and population trends. Delphinids can also mediate the translocation and recycling of limiting nutrients between spatially distinct ecosystems on a diel basis. Despite intriguing possibilities, large gaps remain in our understanding of the roles and importance of small cetaceans in aquatic ecosystems, both marine and freshwater.
Networks of no-take marine protected areas (MPAs), where all extractive activities are prohibited, are the most effective tool to directly protect marine ecosystems from destructive and unsustainable human activities. No-take MPAs and MPA networks have been globally implemented in coastal seas, and their success has been significantly enhanced where science-based biophysical guidelines have informed their design. Increasingly, as human pressure on marine ecosystems is expanding further offshore, governments are establishing offshore MPAs—some very large—or MPA networks. Globally, there are growing calls from scientists, non-government organisations, and national governments to set global conservation targets upwards of 30%. Given that most of the ocean is found either in the high seas or offshore within national Exclusive Economic Zones, large offshore MPAs or networks of MPAs must be a major component of these global targets for ocean protection. However, without adequate design, these offshore MPAs risk being placed to minimise conflict with economic interests, rather than to maximise biodiversity protection. This paper describes detailed biophysical guidelines that managers can use to design effective networks of no-take MPAs in offshore environments. We conducted a systematic review of existing biophysical design guidelines for networks of MPAs in coastal seas, and found consistent elements relating to size, shape, connectivity, timeframes, and representation of biophysical features. However, few of the guidelines are tailored to offshore environments, and few of the large offshore MPAs currently in place were designed systematically. We discuss how the common inshore design guidelines should be revised to be responsive to the characteristics of offshore ecosystems, including giving consideration of issues of scale, data availability, and uncertainty. We propose 10 biophysical guidelines that can be used to systematically design offshore networks of MPAs which will also contribute to the global goal of at least 30% protection globally. Finally, we offer three priority guidelines that reflect the unique conservation needs of offshore ecosystems: emphasising the need for larger MPAs; maximising the inclusion of special features that are known and mapped; and representing minimum percentages of habitats, or, where mapped, bioregions. Ultimately, MPA guidelines need to be embedded within an adaptive management framework, and have the flexibility to respond to emerging knowledge and new challenges.
It is not enough to simply designate a protected area. According to the Convention on Biological Diversity’s Aichi Target 11, these sites should be governed and managed effectively and equitably. Equitable (i.e., fair and inclusive) conservation is vital to ensuring effective protection of natural resources while maintaining human well-being. Yet, equity tends to be overlooked in protected area assessments. Three marine protected areas (MPAs) in Great Britain, Northern Ireland, and the Republic of Ireland were selected to assess equitable governance and management in the Irish Sea. This is one of the first studies to assess equity across multiple stakeholder groups in MPAs. The Site-level Assessment for Governance and Equity (SAGE) toolkit, developed by the International Institute for Environment and Development (IIED) to address the gap in equity assessments, was used to evaluate equitable governance and management in these MPAs. Based on the three dimensions of equity (recognition, distribution, and procedure), SAGE contains Likert-scale questions to assess good governance by evaluating how different stakeholder groups perceive their protected area’s management and how included they feel in decision-making. Quantitative data from SAGE is complemented by qualitative data from semi-structured interviews with stakeholders to understand the impact MPA management has on local communities and MPA users. The results of this study reveal a lack of communication between MPA authorities and local stakeholders. They highlight the need for co-management in the form of inclusive partnerships as an alternative to the current top-down governance approach favoed in the United Kingdom and Ireland.
Marine protected areas (MPAs) are designated parts of the ocean that restrict human activities to a certain degree. MPAs are established around the world using a wide range of legislative instruments and thus come in a variety of forms and shapes. Despite being regarded as the “cornerstone” of global marine conservation efforts, they currently cover less than 10% of the ocean surface. Individual MPAs aim to achieve goals ranging from the protection of specific habitats or species to sustaining certain commercial activities, such as fishing. By default, the establishment of MPAs intertwines social, ecological and economic considerations. Yet, the emphasis put on each of these domains can vary substantially when setting on-the-ground objectives, frequently creating conflict among stakeholders. In this manuscript, we first discuss current international conservation targets as well as potential future goals and delve into the question of how to assess the effectiveness of MPAs. Subsequently, we discuss the ambivalent role of this widely applied management tool at the crossroads between biodiversity conservation and fisheries management. Placing MPAs in a social-ecological framework, we call for clear and measurable goals to evaluate MPAs from an interdisciplinary perspective. Finally, we present the Baltic Sea, with its high degree of anthropogenic impact, long fishing history and comparatively extensive MPA coverage, as an interesting case study to investigate the role of MPAs in promoting a sustainable management of the ocean.
No waters left untouched
We are increasingly aware of human impacts on biodiversity across our planet, especially in terrestrial and marine systems. We know less about fresh waters, including large rivers. Su et al. looked across such systems globally, focusing on several key measures of fish biodiversity. They found that half of all river systems have been heavily affected by human activities, with only very large tropical river basins receiving the lowest levels of change. Fragmentation and non-native species have also led to the homogenization of rivers, with many now containing similar species and fewer specialized lineages.
Science , this issue p. 835
This work sheds light on the recent evolution (≈1915–2015 AD) of Sepetiba Bay (SB; SE Brazil), a subtropical coastal lagoon on the southwestern Brazilian coast, based on a multiproxy approach. Variations in geochemical proxies as well as textural, mineralogical and geochronological data allow us to reconstruct temporally constrained changes in the depositional environments along the SP3 sediment core collected from the central area of SB. At the beginning of the twentieth century, the substrate of the study site was composed of coarse-grained sediments, largely sourced from felsic rocks of proximal areas and deposited under moderate to strong shallow marine hydrodynamics. Since the 1930s, the study area has undergone silting and received high contributions of materials from mafic rocks sourced by river basins. The SP3 core reveals a shallowing-upward sequence due to human-induced silting with significant eutrophication since the middle of 1970, which was caused by significant enrichment of organic matter that was provided by not only marine productivity but also continental and human waste. In addition, the sediments deposited after 1980 exhibit significant enrichment and are moderately to strongly polluted by Cd and Zn. Metals were dispersed by hydrodynamics from the source areas, but diagenetic processes promoted their retention in the sediments. The potential ecological risk index (PERI) indicates that the level of high (considerable) ecological risk is in sediments deposited in ≈1995 (30–32 cm; subsurface). The applied methodology allowed us to understand the thickness of the bottom sediment affected by eutrophication processes and contaminants. Identical methodologies can be applied in other coastal zones, and can provide useful information to decision makers and stakeholders that manage those areas.
Bather protection nets have been in place off the coast of KwaZulu-Natal (KZN), South Africa, since the 1950’s. Besides sharks, they also catch a number of other marine vertebrates, including dolphins, the majority of which are Indo-Pacific bottlenose dolphins Tursiops aduncus. Previous analyses of dolphin bycatch in the nets indicated the potential impacts on the local populations, but a lack of information on population structure has to-date hindered a more detailed assessment. A recent re-assessment of the status and population delineations of T. aduncus off South Africa prompted a re-examination of demographic, spatial, and temporal patterns of its catches in bather protection nets over a 36-year period (January 1980 to December 2015). In total, 1169 dolphins were caught, including a slightly greater number of females and juveniles than other sex-classes, raising concern about the potential long-term effects on population demographics. More dolphins were caught off the North than the South coast. Temporal trends indicate that the bycatch during June and July every year (peak Sardine Run period) as a percentage of overall dolphin bycatch has been steadily decreasing from 39.8% in 1980 to 13% in 2015. A large inter-annual fluctuation can be seen, probably as a result of the inter-annual intensity of the Sardine Run. Although our results do not indicate a long-term decline of the individual populations as previously predicted, revised abundance estimates and data on the demographics and movement patterns of the animals are urgently required to accurately assess the impact of bycatch on the Indo-Pacific bottlenose dolphin populations off KZN and to advise conservation and management decisions going forward.
Aim
As a step towards providing support for an ecological approach to strengthening marine protected areas (MPAs) and meeting international commitments, this study combines cumulative impact assessment and conservation planning approach to undertake a large‐scale spatial prioritization.
Location
Exclusive Economic Zone (EEZ) of Brazil, Southwest Atlantic Ocean.
Methods
We developed a prioritization approach to protecting different habitat types, threatened species ranges and ecological connectivity, while also mitigating the impacts of multiple threats on biodiversity. When identifying priorities for conservation, we accounted for the co‐occurrence of 24 human threats and the distribution of 161 marine habitats and 143 threatened species, as well as their associated vulnerabilities. Additionally, we compared our conservation priorities with MPAs proposed by local stakeholders.
Results
We show that impacts to habitats and species are widespread and identify hot spots of cumulative impacts on inshore and offshore areas. Industrial fisheries, climate change and land‐based activities were the most severe threats to biodiversity. The highest priorities were mostly found towards the coast due to the high cumulative impacts found in nearshore areas. As expected, our systematic approach showed a better performance on selecting priority sites when compared to the MPAs proposed by local stakeholders without a typical conservation planning exercise, increasing the existing coverage of MPAs by only 7.9%. However, we found that proposed MPAs still provide some opportunities to protect areas facing high levels of threats.
Main conclusions
The study presents a blueprint of how to embrace a comprehensive ecological approach when identifying strategic priorities for conservation. We advocate protecting these crucial areas from degradation in emerging conservation efforts is key to maintain their biodiversity value.
Indicators for preserving marine biodiversity include knowledge of how the spatial distribution and critical habitats of species overlap with human activities and impacts. Such indicators are key tools for marine spatial planning, a process that identifies and resolves conflicts between human uses and the conservation of marine environments. The common bottlenose dolphin in the Mediterranean Sea is considered a vulnerable species by the IUCN Red List and a priority species of the EU Habitat Directive. Here, we estimated spatio-temporal patterns of the species occurrence in the area around one Marine Protected Area (MPA) and two Sites of Community Importance (SCI) of the North western Sardinia, with the aim to predict the species distribution and the main links with the environmental factors and boat traffic. To evaluate whether dolphin groups with calves showed any habitat preference different from groups without calves, separate models for both type of groups were done. The most important contributing variables to the dolphin habitat suitability models were the likelihood of boat presence, habitat type and mean sea surface temperature. Different model outputs were obtained depending on dolphin group composition. The area of high likelihood of dolphin presence ranged between 30 and 60 km² and was smaller for groups with calves. Further, the area of highest dolphin habitat suitability overlaps with the area of high boat traffic, suggesting that boating in the study site is a potential relevant anthropogenic threat to dolphins. Particularly, boating is concentrated inside and around the MPA/SCIs, indicating the need for stronger restriction measures. We propose updated SCI boundaries for effective protection of common bottlenose dolphins. These areas and the suggestions of regulation are specifically aimed at reducing the impact of boating on dolphins, especially for groups with calves. Synthesis and applications. Management measures should be designed based on the data here provided, and then implemented and enforced to decrease dolphin-boat interactions, especially for mother-calf pairs. The creation of new coastal SCIs should be considered especially where boat traffic overlaps with areas most suitable for dolphins. In these SCIs, boating should be managed to limit disturbance, avoidance or alterations of dolphin vital behavior.
Marine protected areas (MPAs) are essential to human well-being and usually part of spatial planning processes for managing coastal and marine areas. In Brazil, national-level spatial planning processes are still incipient. This article offers a systematic review through a comparative meta-analysis of the literature on MPAs and spatial planning based on the following questions: (I) What topics are investigated in spatial planning in MPAs worldwide? and (II) What are the advances and trends of these topics in Brazilian MPAs? Specific goals of this study are (I) to identify studies on Brazil; and (II) to compare and contrast these with studies performed elsewhere. The PRISMA report was used to select literature, with a focus on three spatial contexts (I) outside Brazil, analyzing studies from other countries; (II) in Brazil; and (III) a case study in Brazil that focuses on a sustainable-use area in northeastern Pará. Studies outside Brazil showed three major groups of themes: (I) planning and tools; (II) stakeholders; and (III) the ecology of non-human species. For the Brazilian context, studies were grouped into five major themes: (I) small-scale fishing practices and conflicts; (II) participation in protected areas; (III) technical aspects of the planning process, (IV) zoning; and (V) mapping. The local case study investigates socio-cultural sustainability and tourism. All identified studies relate to use, but have a greater focus on conservation and, especially abroad, on species and ecosystems. There are few reviews or comparative studies that could help to draw parallels between the different spatial planning settings. We conclude that synthesis work on spatial management strategies worldwide is needed, including the elaboration of frameworks to develop measures to address the widespread lack of data and spatial planning expertise. Collaborative networks of researchers and practitioners are needed for this. The novelty in our study is that it examines MPAs and spatial planning research at three spatial contexts with innovative methodologies to represent the current state of the spatial planning discourse in coastal and marine conservation.
Sympatric species are expected to differ in ecological requirements to minimize niche overlap and avoid competition. Here we assess the trophic interactions among three coexisting dolphin species from southern Brazil: the franciscana dolphin (Pontoporia blainvillei), the Guiana dolphin (Sotalia guianensis), and the Lahille's bottlenose dolphin (Tursiops truncatus gephyreus). We evaluated temporal variation in carbon (δ 13 C) and nitrogen (δ 15 N) isotope values of bone collagen to examine potential dietary shifts resulting from increased fishing activity over the past three decades. We estimated the degree of niche overlap among these species and the contribution of potential prey sources to their diet. δ 15 N values were consistent among species and across years, while δ 13 C values increased for Guiana dolphins and decreased for bottlenose dolphins, suggesting changes in diet and/or foraging habitats through time. The similar δ 13 C and δ 15 N values and the high niche overlap between Guiana and bottlenose dolphins indicate that these species are primarily feeding on demersal prey. The franciscana diet is primarily composed of pelagic prey, resulting in a lower niche
The common bottlenose dolphin, Tursiops truncatus, is widely distributed. However, information about its ecology and behavior in Brazilian waters is scarce especially about the ‘offshore’ ecotype, an Evolutionarily Significant Unit in the Southwest Atlantic. We report for the first time the occurrence, behavior and habitat use of bottlenose dolphins Tursiops truncatus truncatus, in two Marine Protected Areas (MPA) in Cabo Frio coast, Brazil. There were fifteen sightings of different groups throughout the year. An overall of 429 individuals were photo-identified. 90.7% dolphins did not present a degree of residence, 1.4% dolphins were considered with high residency to the area, 5.8% medium and 2.1% low. Our habitat use map indicated dolphins were more common off ~10km from Cabo Frio municipality and between depths around 20-70m. Bottlenose dolphins on Cabo Frio coast were more frequently observed performing travelling, followed by foraging and socio-sexual behavior. Group sizes varied from three to 120 individuals. Larger groups were observed when travelling and foraging. Despite the existence of two local Marine Protected Areas, the fast human development in Cabo Frio may threaten this important area for bottlenose dolphins in terms of food resources and shelter from predators.
Conservation science is a mission-driven discipline, yet there are few assessments on whether conservation practices follow scientific recommendations, and thus missed opportunities for improvement. Brazil has among the greatest gaps in species protection by Marine Protected Areas (MPAs) globally and is thus a priority for future marine conservation efforts. In this paper, we assess the federal marine protected area (MPA) planning process in Brazil and compare it to a systematic conservation planning approach, focused on achieving conservation benefits while minimizing associated costs. We review the available information for all (70) federal MPAs, and the 26 associated management plans available. We found five simple opportunities for improving national MPA planning: (1) identifying specific and quantitative objectives and linking them to timeframes and budgets; (2) developing strategic monitoring and evaluation programs focused on MPA performance; (3) enabling local stakeholders to participate in planning processes, (4) explicitly considering MPA costs and leveraging existing sources of funding, and (5) decentralizing resource management and empowering local stakeholders to manage resources sustainably. Many reviewed MPA planning efforts fall short in providing clear management guidance and our recommendations can foster a stronger platform for the conservation and sustainable use of marine resources in Brazil.
Species distribution models (SDMs) constitute the most common class of models across ecology, evolution and conservation. The advent of ready‐to‐use software packages and increasing availability of digital geoinformation have considerably assisted the application of SDMs in the past decade, greatly enabling their broader use for informing conservation and management, and for quantifying impacts from global change. However, models must be fit for purpose, with all important aspects of their development and applications properly considered. Despite the widespread use of SDMs, standardisation and documentation of modelling protocols remain limited, which makes it hard to assess whether development steps are appropriate for end use. To address these issues, we propose a standard protocol for reporting SDMs, with an emphasis on describing how a study's objective is achieved through a series of modeling decisions. We call this the ODMAP (Overview, Data, Model, Assessment and Prediction) protocol, as its components reflect the main steps involved in building SDMs and other empirically‐based biodiversity models. The ODMAP protocol serves two main purposes. First, it provides a checklist for authors, detailing key steps for model building and analyses, and thus represents a quick guide and generic workflow for modern SDMs. Second, it introduces a structured format for documenting and communicating the models, ensuring transparency and reproducibility, facilitating peer review and expert evaluation of model quality, as well as meta‐analyses. We detail all elements of ODMAP, and explain how it can be used for different model objectives and applications, and how it complements efforts to store associated metadata and define modelling standards. We illustrate its utility by revisiting nine previously published case studies, and provide an interactive web‐based application to facilitate its use. We plan to advance ODMAP by encouraging its further refinement and adoption by the scientific community.
Concern about the effects of maritime vessel collisions with marine animals is increasing worldwide. To date, most scientific publications on this topic have focused on the collisions between large vessels and large whales. However, our review found that at least 75 marine species are affected, including smaller whales, dolphins, porpoises, dugongs, manatees, whale sharks, sharks, seals, sea otters, sea turtles, penguins, and fish. Collision incidents with smaller species are scarce, likely as a result of reporting biases. Some of these biases can be addressed through the establishment of species-specific necropsy protocols to ensure reliable identification of collision-related injury, particularly blunt force trauma. In addition, creating a ship strike database for smaller species can assist in identifying the species most frequently involved in collisions, identifying high-risk areas, and determining species-specific relationships between vessel speed and lethal injury. The International Whaling Commission database on collisions with large whales provides a good example of this type of database and its potential uses. Prioritizing the establishment of a species-specific necropsy protocol and a database for smaller species as well as the identification of high-risk areas for species other than large whales, would be a valuable step toward the mitigation of collisions with smaller species.
The rapid pace of environmental change in the Anthropocene necessitates the development of a new suite of tools for measuring ecosystem dynamics. Sentinel species can provide insight into ecosystem function, identify hidden risks to human health, and predict future change. As sentinels, marine apex (top) predators offer a unique perspective into ocean processes, given that they can move across ocean basins and amplify trophic information across multiple spatiotemporal scales. Because use of the terms “ecosystem sentinel” and “climate sentinel” has proliferated in the scientific literature, there is a need to identify the properties that make marine predators effective sentinels. We provide a clear definition of the term “sentinel”, review the attributes of species identified as sentinels, and describe how a suite of such sentinels could strengthen our understanding and management of marine ecosystems. We contend that the use of marine predators as ecosystem sentinels will enable rapid response and adaptation to ecosystem variability and change.
Ship strikes are one of the main human-induced threats to whale survival. A variety of measures have been used or proposed to reduce collisions and subsequent mortality of whales. These include operational measures, such as mandatory speed reduction, or technical ones, such as detection tools. There is, however, a lack of a systematic approach to assessing the various measures that can mitigate the risk of ship collisions with whales. In this paper, a holistic approach is proposed to evaluate mitigation measures based on a risk assessment framework that has been adopted by the International Maritime Organization (IMO), namely the Formal Safety Assessment (FSA). Formal Safety Assessment (FSA) is "a rational and systematic process for assessing the risk related to maritime safety and the protection of the marine environment and for evaluating the costs and benefits of IMO's options for reducing these risks". The paper conceptualizes the use of a systematic risk assessment methodology, namely the FSA, to assess measures to reduce the risk of collisions between ships and whales.
The number of marine watercraft is on the rise—from private boats in coastal areas to commercial ships crossing oceans. A concomitant increase in underwater noise has been reported in several regions around the globe. Given the important role sound plays in the life functions of marine mammals, research on the potential effects of vessel noise has grown—in particular since the year 2000. We provide an overview of this literature, showing that studies have been patchy in terms of their coverage of species, habitats, vessel types, and types of impact investigated. The documented effects include behavioral and acoustic responses, auditory masking, and stress. We identify knowledge gaps: There appears a bias to more easily accessible species (i.e., bottlenose dolphins and humpback whales), whereas there is a paucity of literature addressing vessel noise impacts on river dolphins, even though some of these species experience chronic noise from boats. Similarly, little is known about the potential effects of ship noise on pelagic and deep-diving marine mammals, even though ship noise is focused in a downward direction, reaching great depth at little acoustic loss and potentially coupling into sound propagation channels in which sound may transmit over long ranges. We explain the fundamental concepts involved in the generation and propagation of vessel noise and point out common problems with both physics and biology: Recordings of ship noise might be affected by unidentified artifacts, and noise exposure can be both under- and over-estimated by tens of decibel if the local sound propagation conditions are not considered. The lack of anthropogenic (e.g., different vessel types), environmental (e.g., different sea states or presence/absence of prey), and biological (e.g., different demographics) controls is a common problem, as is a lack of understanding what constitutes the ‘normal’ range of behaviors. Last but not least, the biological significance of observed responses is mostly unknown. Moving forward, standards on study design, data analysis, and reporting are badly needed so that results are comparable (across space and time) and so that data can be synthesized to address the grand unknowns: the role of context and the consequences of chronic exposures.
Reducing speeds across shipping fleets has been shown to make a substantial contribution to effective short term measures for reducing greenhouse gas (GHG) emissions, working toward the goal adopted by the International Maritime Organization (IMO) in April 2018 to reduce the total annual GHG emission by at least 50% by 2050 compared to 2008. I review modeling work on GHG emissions and also on the relationships between underwater noise, whale collision risk and speed. I examine different speed reduction scenarios that would contribute to GHG reduction targets, and the other environmental benefits of reduced underwater noise and risk of collisions with marine life. A modest 10% speed reduction across the global fleet has been estimated to reduce overall GHG emissions by around 13% (Faber et al., 2017) and improve the probability of meeting GHG targets by 23% (Comer et al., 2018). I conclude that such a 10% speed reduction, could reduce the total sound energy from shipping by around 40%. The associated reduction in overall ship strike risk has higher uncertainty but could be around 50%. This would benefit whale populations globally and complement current efforts to reduce collision risk in identified high risk areas through small changes in routing.
Humans interact with the oceans in diverse and profound ways. The scope, magnitude, footprint and ultimate cumulative impacts of human activities can threaten ocean ecosystems and have changed over time, resulting in new challenges and threats to marine ecosystems. A fundamental gap in understanding how humanity is affecting the oceans is our limited knowledge about the pace of change in cumulative impact on ocean ecosystems from expanding human activities – and the patterns, locations and drivers of most significant change. To help address this, we combined high resolution, annual data on the intensity of 14 human stressors and their impact on 21 marine ecosystems over 11 years (2003–2013) to assess pace of change in cumulative impacts on global oceans, where and how much that pace differs across the ocean, and which stressors and their impacts contribute most to those changes. We found that most of the ocean (59%) is experiencing significantly increasing cumulative impact, in particular due to climate change but also from fishing, land-based pollution and shipping. Nearly all countries saw increases in cumulative impacts in their coastal waters, as did all ecosystems, with coral reefs, seagrasses and mangroves at most risk. Mitigation of stressors most contributing to increases in overall cumulative impacts is urgently needed to sustain healthy oceans.
Aim
Ship strikes are one of the largest sources of human‐caused mortality for baleen whales on the West Coast of the United States. Reducing ship‐strike risk in this region is complicated by changes in ship traffic that resulted from air pollution regulations and economic factors. A diverse group of stakeholders was convened to develop strategies to reduce ship‐strike risk in the Southern California Bight. Strategies proposed by some stakeholders included: (a) adding a shipping route; (b) expanding the existing area to be avoided (ATBA); and (c) reducing ship speeds.
Location
Southern California Bight, off the coast of California, United States.
Methods
We developed methods to estimate ship traffic in the stakeholder‐derived strategies using 8 years of ship traffic data. To assess ship‐strike risk for fin, humpback, and blue whales, we used habitat models developed from 7 years of survey data and home ranges derived from 53 blue whale tags. We defined collision risk as the co‐occurrence between whales and ships. The risk of a lethal collision was calculated by multiplying collision risk by the probability that a collision is lethal, which is estimated using ship speed.
Results
Speed reductions resulted in a large decrease in the risk of a lethal ship strike. Creating a shipping route or expanding the ATBA reduced the risk of a strike by removing traffic from a whale feeding area. Creating a shipping route was opposed by the United States Navy and the shipping industry, but expanding the ATBA was broadly supported.
Main conclusions
Our analyses suggest that speed reductions and expanding the ATBA may provide an optimal solution for addressing stakeholder needs and reducing ship strikes in the Southern California Bight. The methods we developed can be used to address the global issue of balancing human use of the marine environment with the protection of whale populations.
Despite the recent paradigmatic shift in conservation science, protected areas (PAs), which are associated with seminal conservation strategies, remain a key tool for achieving biodiversity conservation. Nevertheless, PAs’ effectiveness as conservation measures is undermined by conflicts arising within their socio-ecological systems. Potential reasons for the negative impact of the conflicts include the tendency of researchers to emphasise managerial or behavioural aspects of conservation conflicts, while neglecting to develop theoretical foundations for conflict analysis. We aimed to critically review existing conceptual frameworks applied within the broadly defined field of conservation conflicts and to develop a new more comprehensive framework that better reflects contemporary identified challenges within nature conservation. We particularly proposed and emphasised the integration of a geographical perspective within existing interdisciplinary approaches for the application to PA settings. We systemised and unified conflict-related terminology, assessed the contributions and limitations of existing frameworks and identified critical gaps in the field. These gaps are: inadequate recognition of the spatial aspects of conflict analysis, a lack of consistency between individual-level and community-level frameworks and a lack of systematic linkages among the main structural attributes of conflicts, such as determinants, interests or types of conflicts. We systematically distinguished 26 conflict-related terms, including: conflict frames, images, orientations, factors, categories, issues, potential, or intensity. Our framework covers three major conflict components (determinants, dimensions, levels) and foregrounds the socio-psychological and spatial characteristics of PA conflicts, while enabling systemisation of existing conservation conflict typologies.
Phytoplankton blooms are an important, widespread phenomenon in open oceans, coastal waters and freshwaters, supporting food webs and essential ecosystem services. Blooms are even more important in exploited coastal waters for maintaining high resource production. However, the environmental factors driving blooms in shallow productive coastal waters are still unclear, making it difficult to assess how environmental fluctuations influence bloom phenology and productivity. To gain insights into bloom phenology, Chl a fluorescence and meteorological and hydrological parameters were monitored at high-frequency (15 min) and nutrient concentrations and phytoplankton abundance and diversity, were monitored weekly in a typical Mediterranean shallow coastal system (Thau Lagoon). This study was carried out from winter to late spring in two successive years with different climatic conditions: 2014/2015 was typical, but the winter of 2015/2016 was the warmest on record. Rising water temperature was the main driver of phytoplankton blooms. However, blooms were sometimes correlated with winds and sometimes correlated with salinity, suggesting nutrients were supplied by water transport via winds, saltier seawater intake, rain and water flow events. This finding indicates the joint role of these factors in determining the success of phytoplankton blooms. Furthermore, interannual variability showed that winter water temperature was higher in 2016 than in 2015, resulting in lower phytoplankton biomass accumulation in the following spring. Moreover, the phytoplankton abundances and diversity also changed: cyanobacteria (< 1 μm), picoeukaryotes (< 1 μm) and nanoeukaryotes (3–6 μm) increased to the detriment of larger phytoplankton such as diatoms. Water temperature is a key factor affecting phytoplankton bloom dynamics in shallow productive coastal waters and could become crucial with future global warming by modifying bloom phenology and changing phytoplankton community structure, in turn affecting the entire food web and ecosystem services.
Fisheries bycatch is one of the biggest threats to marine mammal populations. A literature review was undertaken to provide a comprehensive assessment and synopsis of gear modifications and technical devices to reduce marine mammal bycatch in commercial trawl, purse seine, longline, gillnet and pot/trap fisheries. Successfully implemented mitigation measures include acoustic deterrent devices (pingers) which reduced the bycatch of some small cetacean species in gillnets, appropriately designed exclusion devices which reduced pinniped bycatch in some trawl fisheries, and various pot/trap guard designs that reduced marine mammal entrapment. However, substantial development and research of mitigation options is required to address the bycatch of a range of species in many fisheries. No reliably effective technical solutions to reduce small cetacean bycatch in trawl nets are available, although loud pingers have shown potential. There are currently no technical options that effectively reduce marine mammal interactions in longline fisheries, although development of catch and hook protection devices is promising. Solutions are also needed for species, particularly pinnipeds and small cetaceans, that are not deterred by pingers and continue to be caught in static gillnets. Large whale entanglements in static gear, particularly buoy lines for pots/traps, needs urgent attention although there is encouraging research on rope-less pot/trap systems and identification of rope colours that are more detectable to whale species. Future mitigation development and deployment requires rigorous scientific testing to determine if significant bycatch reduction has been achieved, as well as consideration of potentially conflicting mitigation outcomes if multiple species are impacted by a fishery.
Several countries, including Brazil, are making compelling case for historical progress towards achieving the targets for marine protection under the Convention on Biological Diversity. However, this can be done through the establishment of large marine protected areas (MPAs) in the open ocean, a conservation strategy that might be only tangential to the core ecological goal of MPA designation, i.e. biodiversity conservation. By using two newly-designated large MPAs in Brazil as an example, we outline three ways in which they indicate poor adherence to best practices in MPA planning: placing no-take MPAs in areas with limited potential for extractive uses, neglecting the need to account for spatial dependencies among areas to maintain populations over time, and the inadequacy of the MPAs to regulate fishing of mobile pelagic species.
Abstarct
The potential disturbance of dolphins from tourism boats has been widely discussed in the literature, in terms of both physical vessel presence and associated underwater noise. However, less attention has been paid to the potential impact of non-tourism vessels, despite these being much more widespread and occurring in greater numbers throughout coastal dolphin habitats. The Indo-Pacific bottlenose dolphin (T. aduncus) community using the Fremantle Inner Harbour, Western Australia, is exposed to high levels of vessel traffic. To investigate whether behavioural responses could be occurring, a non-invasive combination of visual and acoustic monitoring was conducted using a theodolite and an autonomous acoustic logger. Dolphins significantly increased their average movement speeds in high vessel densities, but only for some activity states. Behavioural budgets also changed in the presence of vessels, with animals spending greater time travelling and less time resting or socialising. Finally, multiple whistle characteristics varied with rising levels of broadband noise, and other contextual variables. Despite being acoustically specialised for higher frequencies, dolphins had the strongest acoustic variation during low-frequency noise. This study highlights the complexity of disturbance responses in this species, confirming the need for consideration of both surface and acoustic behaviour alongside appropriate contextual data.
The development of risk assessments for the exposure of protected populations to noise from coastal construction is constrained by uncertainty over the nature and extent of marine mammal responses to man-made noise. Stakeholder concern often focuses on the potential for local displacement caused by impact piling, where piles are hammered into the seabed. To mitigate this threat, use of vibration piling, where piles are shaken into place with a vibratory hammer, is often encouraged due to presumed impact reduction. However, data on comparative responses of cetaceans to these different noise sources are lacking. We studied the responses of bottlenose dolphins and harbor porpoises to both impact and vibration pile driving noise during harbor construction works in northeast Scotland, using passive acoustic monitoring devices to record cetacean activity and noise recorders to measure and predict received noise levels. Local abundance and patterns of occurrence of bottlenose dolphins were also compared with a five-year baseline. The median peak-to-peak source level estimated for impact piling was 240 dB re 1 lPa (single-pulse sound exposure level [SEL] 198 dB re 1 lPa 2 s), and the r.m.s. source level for vibration piling was 192 dB re 1 lPa. Predicted received broadband SEL values 812 m from the piling site were markedly lower due to high propagation loss: 133.4 dB re 1 lPa 2 s (impact) and 128.9 dB re 1 lPa 2 s (vibration). Bottlenose dolphins and harbor porpoises were not excluded from sites in the vicinity of impact piling or vibration piling; nevertheless, some small effects were detected. Bottlenose dolphins spent a reduced period of time in the vicinity of construction works during both impact and vibration piling. The probability of occurrence of both cetacean species was also slightly less during periods of vibration piling. This work provides developers and managers with the first evidence of the comparative effects of vibration and impact piling on small cetaceans, enabling more informed risk assessments, policy frameworks, and mitigation plans. In particular, our results emphasize the need for better understanding of noise levels and behavioral responses to vibration piling before recommending its use to mitigate impact piling.
The prevalence of scars and wounds of anthropogenic origin was assessed in seven different coastal bottlenose dolphin communities ( Tursiops truncatus ) on the south-western coast of Ecuador. Between 2011 and 2017 a total of 117 trips were conducted representing a total sampled distance of 6281 km. Twenty-five of the 189 (13.2%) free-ranging photo-identified dolphins were recorded with dorsal fin damage, V-shaped wounds, sawed edges and deformities in the caudal region. The scarring prevalence ranged from 0 to 44.4% and was associated with either fishing interactions or vessel strikes. Dolphin scarring increased five times in the last 25 years from 2.2 to 11.1% and was correlated with a decrease in population in the inner estuary of the Gulf of Guayaquil. Damaged dorsal fins are associated mainly with fishing gear. V-shaped wounds were recorded in three different communities, Posorja, Estero Salado and Salinas, and given their severity associated with either fishing gear or vessel strikes. During the study period three dolphins were found entangled in fishing gears, two in gillnets and one in a long-line, emphasizing the threats posed by current fishing practice to the species. More effective management measures are urgently needed to reverse the observed population decline. This may include reduction of fishing effort, implementation of area-based approaches to coastal planning (including Marine Protected Area designations) and support for further research to understand the problem. Given the difficulty in taking direct observations, scarring prevalence is proposed as a proxy for estimating boat traffic and fishing gear impacts upon cetaceans.
Bryde’s whales Balaenoptera edeni are the only resident baleen whale species in the Gulf of Mexico (GoMx), where they are extremely rare, have a restricted distribution, and represent a unique evolutionary lineage. The reasons for the restricted distribution and small population size are unknown, but high levels of industrial activity in the GoMx may be a major factor. We evaluated the geospatial overlap of GoMx Bryde’s whales with 2 industries known to impact baleen whale species: commercial shipping and commercial fisheries. We further evaluate potential for impacts by examining the first dive behavior data collected from a kinematic tag attached to a GoMx Bryde’s whale for 3 d. Vessel traffic and fishery effort are low in GoMx Bryde’s whale habitat compared to the rest of the northern GoMx, but several shipping lanes transit through the habitat, and the reef fish bottom longline fishery has considerable effort within the habitat. The tagged whale exhibited diel diving behavior with diurnal deep dives and foraging lunges at or near the sea-floor, and shallow nocturnal diving with 88% of its nighttime spent near the surface within the draught depths of most large commercial vessels. Given the location of commercial shipping traffic in their habitat, ship strikes may pose a threat to this population if whales commonly spend time near the surface, especially at night. Also, if bottom or near-bottom feeding is a normal feeding strategy for these whales, there is potential for gear-entanglements with bottom longline gear. Managing these threats may improve population recovery.
Fishing exclusion zones aim to reduce cetacean bycatch, but often neglect social and ecological side effects, exacerbating social injustices and reshaping fishing practices. We present a case study of an endangered population of Lahille's bottlenose dolphins (Tursiops truncatus gephyreus) in a Brazilian coastal lagoon, known for its unique cooperation with net-casting fishers. However, the local small-scale fisheries (SSF) also employ other fishing gears that contribute to dolphin bycatch, prompting the enforcement of a fishing ban in the area. We investigated fishers' socioeconomic conditions, evidence of social disparities, perceptions on dolphin bycatch, and projected changes on fisheries activities to understand the repercussions of the ban. We categorized 128 surveyed fishers into five groups based on socioeconomic factors and their reliance on dolphin-cooperative and gillnet fisheries. Our findings revealed significant disparities in social capital among fishers and their different attitudes towards dolphin bycatch, highlighting unforeseen consequences. To investigate how fishers would likely shift fishing practices, we considered two management scenarios: 1) should dolphin-fishing cease due to unsuccessful bycatch mitigation, fishing efforts would shift towards shrimp trawling, seine nets, and gillnet effort; 2) if gillnet-fishing is successfully banned as a bycatch mitigation measure, a shift to shrimp trawling and cast net effort. Both scenarios would intensify pressure on shrimp stocks, which are already heavily exploited in this socioecological system. Our research underscores the importance of contemplating alternatives to achieve sustainable outcomes when designing bycatch mitigation measure. Furthermore, our results point to the importance of a participatory governance approach, grounded in the socioeconomic context, to safeguard the livelihoods of small-scale fishers and foster broader conservation efforts beyond species-specific concerns.
Motivation: Impacts of climate change on marine biodiversity are often projected with species distribution modelling using standardized data layers representing physical, chemical and biological conditions of the global ocean. Yet, the available data layers (1) have not been updated to incorporate data of the Sixth Phase of the Coupled Model Intercomparison Project (CMIP6), which comprise the Shared Socioeconomic Pathway (SSP) scenarios; (2) consider a limited number of Earth System Models (ESMs), and (3) miss important variables expected to influence future biodiversity distributions. These limitations might undermine biodiversity impact assessments, by failing to integrate them within the context of the most up-to-date climate change projections, raising the uncertainty in estimates and misinterpreting the exposure of biodiversity to extreme conditions. Here, we provide a significant update of Bio-ORACLE, extending biologically relevant data layers from present-day conditions to the end of the 21st century Shared Socioeconomic Pathway scenarios based on a multi-model ensemble with data from CMIP6. Alongside, we provide R and Python packages for seamless integration in modelling workflows. The data layers aim to enhance the understanding of the potential impacts of climate change on biodiversity and to support well-informed research, conservation and management.
Main Types of Variable Contained: Surface and benthic layers for, chlorophyll-a, diffuse attenuation coefficient, dissolved iron, dissolved oxygen, nitrate, ocean temperature, pH, phosphate, photosynthetic active radiation, total phytoplankton, total cloud fraction, salinity, silicate, sea-water direction, sea-water velocity, topographic slope, topographic aspect, terrain ruggedness index, topographic position index and bathymetry, and surface layers for air temperature, mixed layer depth, sea-ice cover and sea-ice thickness.
Spatial Location and Grain: Global at 0.05° resolution.
Time Period and Grain: Decadal from present-day to the end of the 21st century (2000–2100).
Major Taxa and Level of Measurement: Marine biodiversity associated with surface and epibenthic habitats.
Software Format: A package of functions developed for Python and R software.
Organic contaminants with toxic effects, like the conventional brominated flame retardants (BFRs) and BFRs of emergent concern, and their synergistic effects with other micropollutants, can be an additional threat to delphinids. Rough-toothed dolphins (Steno bredanensis) populations strongly associated with coastal environments already face a potential risk of decline due to high exposure to organochlorine pollutants. Moreover, natural organobromine compounds are important indicators of the environment's health. Polybrominated diphenyl ethers (PBDEs), pentabromoethylbenzene (PBEB), hexabromobenzene (HBB) and the methoxylated PBDEs (MeO-BDEs) were determined in the blubber of rough-toothed dolphins from three ecological populations from the Southwestern Atlantic Ocean (Southeastern, Southern and Outer Continental Shelf/Southern populations, SE, S, and OCS/S, respectively). The profile was dominated by the naturally produced MeO-BDE (mainly 2'-MeO-BDE 68 and 6-MeO-BDE 47), followed by the anthropogenic BFRs PBDEs (mainly BDE 47). Median ΣMeO-BDE concentrations varied between 705.4 and 3346.0 ng g-1 lw among populations and ΣPBDE from 89.4 until 538.0 ng g-1 lw. Concentrations of anthropogenic organobromine compounds (ΣPBDE, BDE 99 and BDE 100) were higher in SE population than in OCS/S, indicating a coast - ocean gradient of contamination. Negative correlations were found between the concentration of the natural compounds and age, suggesting their metabolization and/or biodilution and maternal transference. Conversely, positive correlations were found between the concentrations of BDE 153 and BDE 154 and age, indicating low biotransformation capability of these heavy congeners. The levels of PBDEs found are concerning, particularly for SE population, because they are similar to concentrations known for the onset of endocrine disruption in other marine mammals and may be an additional threat to a population in hotspot for chemical pollution.
Consistency in conservation
Marine protected areas (MPAs) are now well established globally as tools for conservation, for enhancing marine biodiversity, and for promoting sustainable fisheries. That said, which regions are labeled as MPAs varies substantially, from those that full protect marine species and prohibit human extraction to those that permit everything from intensive fishing to mining. This inconsistency can in some cases inhibit both conservation and quantifying the proportion of the marine environment that is truly protected. Grorud-Colvert et al . review the consistency of MPAs and propose a framework by which levels of protection can be evaluated and improved. —SNV
The coastal habit and site fidelity reported for Sotalia guianensis make this species especially vulnerable to human activities. Thus, ecological studies focusing on the habitat use of the populations are essential for S. guianensis protection, as it helps to identify critical areas for conservation. The present study aims to analyze the habitat use by Sotalia guianensis in three bays in southeastern Brazil: Guanabara Bay (GB 1), Sepetiba Bay (SB 2) and Ilha Grande Bay (IGB 3). From 2017 to 2019, four surveys per month were carried out in each bay on board of outboard-powered boats. After locating a group of dolphins, researchers recorded data every five minutes, applying the focal-group method. Information collected included geographical position, time of day, group size and composition, predominant behavioral state, and local depth in meters. The ArcGIS software was selected to create distribution maps and estimate the area use using the fixed Kernel Density method (KDE). The variables collected were statistically compared within and between populations. Feeding was the predominant behavior (frequency of 84.2% in GB, 73.3% in SB and 52.2% in IGB), but behavior frequencies differed between populations (X 2 = 57.622, df=2, p < 0.00001). Group size and composition also varied according to the study area (KW size: H 2,732 = 68.479, p < 0.0001; KW composition: H 2,732 = 85.311, p < 0.001), IGB and SB showing large aggregations with many calves and GB, small groups. In GB, dolphin distribution was restricted to shallow waters of the northeastern region and central channel (K95% = 9.9 km 2 ; K50% = 1.2 km 2). Guiana dolphins from SB selected greater depths, concentrating in the central region (K95% = 190.6 km 2 ; K50% = 32.6 km 2). In IGB, dolphins occurred in an extensive area (K95% = 264.9 km 2 ; K50% = 42.5 km 2), though observed more frequently in shallow waters of the western region. The results described can contribute to a better knowledge of the populations and serve as a basis for conservation strategies.
In recent years, the use of ecological niche models (ENMs) and species distribution models (SDMs) to explore the patterns and processes behind observed distribution of species has experienced an explosive growth. Although the use of these methods has been less common and more recent in marine ecosystems than in a terrestrial context, they have shown significant increases in use and applications. Herein, we provide a systematic review of 328 articles on marine ENMs and SDMs published between 1990 and 2016, aiming to identify their main applications and the diversity of methodological frameworks in which they are developed, including spatial scale, geographic realm, taxonomic groups assessed, algorithms implemented, and data sources. Of the 328 studies, 48 % were at local scales, with a hotspot of research effort in the North Atlantic Ocean. Most studies were based on correlative approaches and were used to answer ecological or biogeographic questions about mechanisms underlying geographic ranges (64 %). A few attempted to evaluate impacts of climate change (19 %) or to develop strategies for conservation (11 %). Several correlative techniques have been used, but most common was the machine-learning approach Maxent (46 %) and statistical approaches such as generalized additive models GAMs (22 %) and generalized linear models, GLMs (14 %). The groups most studied were fish (23 %), molluscs (16 %), and marine mammals (14 %), the first two with commercial importance and the last important for conservation. We noted a lack of clarity regarding the definitions of ENMs versus SDMs, and a rather consistent failure to differentiate between them. This review exposed a need to know, reduce, and report error and uncertainty associated with species’ occurrence records and environmental data. In addition, particular to marine realms, a third dimension should be incorporated into the modelling process, referring to the vertical position of the species, which will improve the precision and utility of these models. So too is of paramount importance the consideration of temporal and spatial resolution of environmental layers to adequately represent the dynamic nature of marine ecosystems, especially in the case of highly mobile species.
Evidence-based policy, with proven efficacy, is key to the mitigation of human-wildlife conflict. Voluntary agreements to implement conservation actions can take less time to implement than mandatory policies. However, their efficacy is questionable as they rely on the awareness of the measures, cooperation, and goodwill of affected stakeholders. The aim of this study was to examine the efficacy of voluntary ship strike mitigation measures implemented in 2013 to protect a threatened, resident population of Bryde's whales (Balaenoptera edeni brydei) in the Hauraki Gulf, New Zealand. Automatic Identification System (AIS) and whale sightings data were used to determine the distribution and density of ships and whales throughout the Gulf to quantify and assess compliance to the voluntary 10 kt speed limit, and subsequently the risk of lethal ship strike to whales. From October 2014–September 2016, the location of 189 groups of whales and shipping routes of 703 vessels ≥70 m in length were plotted using ArcGIS. Hotspots of preferred whale habitat differed from 2010 to 2013, but shipping traffic density did not. Probability of lethal ship strike to whales in the Gulf has nearly halved (26%) since 2013 (51%) due to a reduction in average vessel speed from 13.2 kt to 10 kt. Observation and reporting systems developed to reduce potential ship strike events, were analysed at a fine scale using reporting rates and AIS data to measure the reactions of ships to real-time reports. Few whale sightings were reported to Harbor Control (n = 37; 8% shipping, 68% whale watch vessel, 24% other vessel types), and no ships diverted course to avoid reported whale locations. This study highlights the importance of testing the efficacy of conservation mitigation measures, as effective voluntary actions may provide a means to reduce the threat of ship strike to whales.
This book introduces the key stages of niche-based habitat suitability model building, evaluation and prediction required for understanding and predicting future patterns of species and biodiversity. Beginning with the main theory behind ecological niches and species distributions, the book proceeds through all major steps of model building, from conceptualization and model training to model evaluation and spatio-temporal predictions. Extensive examples using R support graduate students and researchers in quantifying ecological niches and predicting species distributions with their own data, and help to address key environmental and conservation problems. Reflecting this highly active field of research, the book incorporates the latest developments from informatics and statistics, as well as using data from remote sources such as satellite imagery. A website at www.unil.ch/hsdm contains the codes and supporting material required to run the examples and teach courses. With applications in evolutionary biology, biogeography and conservation biology, the book emphasizes how these models can be used to make predictions in global and regional biodiversity assessments Written by highly experienced researchers in this active field, the book represents a contribution to strengthen modeling standards in basic and applied habitat suitability model research The most recent developments in informatics, statistics and data manipulation in R are incorporated. © Antoine Guisan, Wilfried Thuiller, and Niklaus E. Zimmermann 2017. All rights reserved.