Priority Threats Research Articles

Management and research efforts are failing dolphins, porpoises, and other toothed whales

Despite being subject to intensive research and public interest many populations of dolphins, porpoises, and other toothed whales (small cetaceans) continue to decline, and several species are on the verge of extinction. We examine small cetacean status, human activities driving extinction risk, and whether research efforts are addressing priority threats. We estimate that 22% of small cetaceans are threatened with extinction, with little signs of improvement in nearly thirty years. Fisheries and coastal habitat degradation are the main predictors of extinction risk. Contrary to popular belief, we show that the causal impact of small-scale fisheries on extinction risk is greater than from large-scale fisheries. Fisheries management strength had little influence on extinction risk, suggesting that the implementation of existing measures have been largely ineffective. Alarmingly, we find research efforts for priority threats to be vastly underrepresented and so a major shift in research focus is required. Small cetaceans are among the lower hanging fruits of marine conservation; continued failure to halt their decline bodes poorly for tackling marine biodiversity loss and avoiding an Anthropocene mass extinction.

A threat analysis for the world’s most threatened turtle (Rafetus swinhoei)

We conducted a comprehensive threat analysis of the Swinhoe’s softshell turtle (Rafetus swinhoei), the most endangered freshwater turtle in the world, historically occurring along river systems in Vietnam and China, but currently almost extinct. Here, our goal was to identify the pressures along two main rivers in Vietnam (Black and Red rivers, both extending into Yunnan, People’s Republic of China), building a conceptual framework to understand the causal relationships among driving forces, threats, and the target species. We involved a panel of experts who identified two priority direct threats in Vietnam, classified following the IUCN standard taxonomy, and showing the highest Magnitude (as a proxy of threat pressure): (i) Habitat loss at nesting sites (LOS; code 1.2 - Commercial & industrial areas) and, (ii) Land conversion due to settlements (LAN; code 1.1 - Housing & urban areas). Threats showed a comparable (i.e., not significantly different) Magnitude in the two rivers (Mann-Whitney U test). Experts also identified the underlying driving forces behind these threats: (i) demographic drivers (due to a rapid population growth in the last decades) causing LAN and LOS, as the priority threats, but also sand mining, and water pollution; (ii) economic drivers induced by high poverty in local populations and causing harvesting (fishing activities and related markets), the needs of power supply for economic activities (e.g., dams), and recreational activities; (iii) ethical drivers linked to conservation project teams (limited funds and divergent points about strategies to carry out). Preliminary data for China suggest HAR (Harvesting by native fishers; code 5.4) and POL (water pollution; code 9.2) as priority threats. Threat analysis is an useful tool in the early stages of a conservation project during the context analysis, helping to define priorities for conservation and management.

Integrating biogeographic approach into classical biological control: Assessing the climate matching and ecological niche overlap of two natural enemies against common ragweed in China

Plant invasion is considered a high priority threat to biodiversity, ecosystems, the environment, and human health worldwide. Classical biological control (biocontrol) is a generally safer and more environmentally benign measure than chemical controls in managing invasive alien plants (IAPs). However, the impacts of climate change and the importance of climate matching in ensuring the efficiency of biocontrol candidates in controlling IAPs are likely to be underestimated. Here, based on the ensemble model and n-dimensional hypervolumes concepts, we estimated the overlapping areas between Ambrosia artemisiifolia and its two most effective natural enemies (Ophraella communa and Epiblema strenuana) under climate change in China. Moreover, we compared their ecological niches, further assessing the impact of climate change on the efficiency of two natural enemies in controlling A. artemisiifolia in China. We found that the potentially suitable areas of the two natural enemies and A. artemisiifolia were primarily influenced by temperature and human influence index variables. Under near-current climate, the overlapping area between O. communa and A. artemisiifolia was the largest, followed by E. strenuana and A. artemisiifolia, and both two natural enemies and A. artemisiifolia. The ecological niche between A. artemisiifolia and O. communa was most similar (0.64), followed by A. artemisiifolia and E. strenuana (0.55). The separate control (the niche separation areas of the two natural enemies against A. artemisiifolia) and joint-control (the niche overlap areas of the two natural enemies against A. artemisiifolia) efficiencies of the two natural enemies against A. artemisiifolia will both increase in future climates (the 2030s and 2050s) in northern and northeastern China. Our findings demonstrate a new approach to assess control efficiency and screen potential release areas of two natural enemies against A. artemisiifolia in China without the need for actual field release or experimentation. Moreover, our findings provide important clues for ensuring the classical biocontrol of IAPs worldwide.

The effects of experience and uncertainty on hypothesis generation and testing in threat assessment

AbstractThis study explored the decision‐making processes of soldiers as they evaluated scenarios containing information offering various levels of certainty. Soldiers with different levels of experience read scenarios that presented potential threats and then identified the priority threat, their confidence in this identification, and the cues they used to identify priority threats. Soldiers then searched for additional scenario‐relevant information and modified their reports if their assessments changed. Compared with inexperienced soldiers, experienced soldiers reported a greater number of priority threats and informative cues and were more likely to search additional topics that matched details in their initial assessments. High certainty scenarios yielded more identified threats, more cues, and higher confidence in initial reports. Soldiers' initial assessments rarely changed after additional information searches, but when they did, they were associated with low initial confidence.

Identifying a pathway towards recovery for depleted wild Pacific salmon populations in a large watershed under multiple stressors

Abstract Pacific salmon (Oncorhynchus spp.) support coastal and freshwater ecosystems, economies and cultures, but many populations have declined. We used priority threat management (PTM), a decision‐support framework for prioritizing conservation investments, to identify management strategies that could support thriving populations of wild salmon over 25 years. We evaluated the potential benefits of 14 strategies spanning fisheries, habitat, pollution, pathogens, hatcheries and predation management dimensions on 19 conservation units (CUs)—genetically and ecologically distinct populations—of the five Pacific salmon species in the lower Fraser River, British Columbia, Canada. The PTM assessment indicated that under the current trajectory of ‘business as usual’, zero CUs were predicted to have >50% chance of thriving in 25 years. Implementation of all management strategies at an annual investment between 45 and 110 million CAD was, however, predicted to achieve >50% chance of thriving for most CUs (n = 16), with nearly half (seven CUs) having a > 60% chance, indicating there is a pathway towards recovery for most populations if we invest now. In fact, substantial gains could be made by investing in five combined habitat strategies, costing 20M CAD annually. These habitat strategies were estimated to bring 14 of 19 salmon CUs above this 50% threshold. Co‐governance between First Nation and provincial and federal Canadian governments to manage salmon populations and harvest, and improved CU‐level monitoring emerged from the expert elicitation as critical ‘enabling’ strategies. By improving the feasibility of different management options, co‐governance brought an additional five CUs above the 60% threshold. Synthesis and applications. Supporting wild salmon in the face of cumulative threats will require strategic investment in effective management strategies, as identified by this priority threat management (PTM) assessment. PTM uses the best available data to objectively assess the potential outcomes of management alternatives. With renewed commitments from provincial and federal Canadian governments to protect and restore salmon populations and their habitats, positive conservation outcomes following implementation of targeted management strategies may be within reach.

A Systematic Review Demonstrates How Surrogate Populations Help Inform Conservation and Management of an Endangered Species—The Case of Cook Inlet, Alaska Belugas

The genetically and geographically isolated Cook Inlet beluga whale (CIB) was listed as endangered under the Endangered Species Act in 2008 and a federal recovery plan was adopted in 2016. Despite these measures, the population has failed to make demonstrable progress toward recovery. Data and knowledge gaps exist, as well as high uncertainty in the recovery plan, regarding the impact and severity of identified threats on CIB health and recovery, particularly for threats driven by anthropogenic factors, and cumulative effects. These data deficiencies may hinder threat prioritization and conservation and management actions. Odontocete populations in similarly ecologically precarious situations may serve as research surrogates to help fill information gaps and guide future CIB research and conservation. Through a systematic review of CIB and selected surrogate species [St. Lawrence beluga (SLB), Hector’s dolphins (HD), and southern resident killer whales (SRKW)], we identify gaps associated with threats described and ranked in the CIB recovery plan. All threats identified by the National Marine Fisheries Services as “high”-concern to CIB recovery, except noise, are lower in publication volume compared to publications related to high concern threats in SLB and SRKW. “Medium” or “low” threats to CIB, such as prey reduction and contaminants, respectively, are identified as higher priority threats in surrogate populations. These topics have been more heavily researched for surrogates and suggests that synthesis of this work may help reduce uncertainty, to aid in informing management actions for CIB. Specifically, publishing volume suggests SLB and SRKW are valuable surrogates for understanding the impacts of noise, prey, and contaminants. Publishing volume is necessary to choose a surrogate, but is not sufficient. Surrogates were chosen based on physiological similarities to CIB as well as their comparable management situations. Therefore, these lower-ranked threats should be ranked more highly and researched specifically in regard to CIB. We use this review to offer management recommendations based on current CIB and surrogate literature regarding listed threats in the CIB recovery plan. Our analyses suggest that CIB may benefit from a revision to and elevation of some low and medium-concern threats such as contaminants, habitat degradation, and prey reduction.

An introduction to decision science for conservation.

Biodiversity conservation decisions are difficult, especially when they involve differing values, complex multidimensional objectives, scarce resources, urgency, and considerable uncertainty. Decision science embodies a theory about how to make difficult decisions and an extensive array of frameworks and tools that make that theory practical. We sought to improve conceptual clarity and practical application of decision science to help decision makers apply decision science to conservation problems. We addressed barriers to the uptake of decision science, including a lack of training and awareness of decision science; confusion over common terminology and which tools and frameworks to apply; and the mistaken impression that applying decision science must be time consuming, expensive, and complex. To aid in navigating the extensive and disparate decision science literature, we clarify meaning of common terms: decision science, decision theory, decision analysis, structured decision‐making, and decision‐support tools. Applying decision science does not have to be complex or time consuming; rather, it begins with knowing how to think through the components of a decision utilizing decision analysis (i.e., define the problem, elicit objectives, develop alternatives, estimate consequences, and perform trade‐offs). This is best achieved by applying a rapid‐prototyping approach. At each step, decision‐support tools can provide additional insight and clarity, whereas decision‐support frameworks (e.g., priority threat management and systematic conservation planning) can aid navigation of multiple steps of a decision analysis for particular contexts. We summarize key decision‐support frameworks and tools and describe to which step of a decision analysis, and to which contexts, each is most useful to apply. Our introduction to decision science will aid in contextualizing current approaches and new developments, and help decision makers begin to apply decision science to conservation problems.

Quorum Sensing Inhibitors to Quench P. aeruginosa Pathogenicity.

The emergence and the dissemination of multidrug-resistant bacteria constitute a major public health issue. Among incriminated Gram-negative bacteria, Pseudomonas aeruginosa has been designated by the WHO as a critical priority threat. During the infection process, this pathogen secretes various virulence factors in order to adhere and colonize host tissues. Furthermore, P. aeruginosa has the capacity to establish biofilms that reinforce its virulence and intrinsic drug resistance. The regulation of biofilm and virulence factor production of this micro-organism is controlled by a specific bacterial communication system named Quorum Sensing (QS). The development of anti-virulence agents targeting QS that could attenuate P. aeruginosa pathogenicity without affecting its growth seems to be a promising new therapeutic strategy. This could prevent the selective pressure put on bacteria by the conventional antibiotics that cause their death and promote resistant strain survival. This review describes the QS-controlled pathogenicity of P. aeruginosa and its different specific QS molecular pathways, as well as the recent advances in the development of innovative QS-quenching anti-virulence agents to fight anti-bioresistance.

“Slowed for several months”: A mixed methods comparison of minor, moderate, and extreme speeders

Speeding remains a major and consistent contributor to motor vehicle fatalities in the U.S. Using a parallel convergent mixed methods approach, we compared minor, moderate, and extreme U.S. speeder types (N = 293) to gain a better understanding of why U.S. drivers speed to the degree that they do. An online survey collected quantitative data on self-reported characteristics, speeding behaviors, and roadway behaviors after key events (collisions, speeding tickets) and given passenger presence. Analysis of qualitative data from participants explaining their roadway behaviors and beliefs identified several speeding-related themes. Themes shared to the same extent by all speeder types include not typically citing speeding a cause of a collision and good drivers not needing to change speeding behaviors (i.e., perceived mastery). However, the permanence and extent of speed reductions after key events and with passengers did vary by speeder type, with minor speeders making more extensive and permanent changes. Qualitative and quantitative data both underscore the perception that speeding is not a high priority threat to roadway safety. Findings suggest continued research using conservative and nuanced definitions of speeding is warranted to understand how similar perceptions result in a spectrum of speeding behaviors.

Major threats to a migratory raptor vary geographically along the eastern Mediterranean flyway

The Convention of Migratory Species aims to protect migratory animals throughout their range, but efficient mitigation of threats facing migratory birds is hindered by poor knowledge about the magnitude and geographic range of threats. We used an expert assessment to prioritise which threats to mitigate in 13 countries along the eastern Mediterranean flyway to protect globally threatened Egyptian Vultures Neophron percnopterus. We informed this assessment by satellite tracking 71 birds to quantify where and how mortalities occurred, surveying 4216 km of powerlines to detect carcasses, conducting 910 interviews to quantify poison use, and by surveying markets and hunters to assess direct persecution. Mortality of 50 birds occurred in Europe and the Mediterranean Sea (44%), the Middle East (18%), and Africa (38%), and mortality causes varied geographically. Inadvertent poisoning resulting from rural stakeholders targeting predators occurred along most of the flyway. On the breeding grounds in eastern Europe and in Saudi-Arabia, poisoning and collision and electrocution are the priority threats to mitigate. Electrocution on small and poorly designed electricity pylons was the priority threat in Turkey, Jordan, Egypt and Ethiopia. Direct persecution for belief-based use of vulture products was the priority threat in Nigeria and Niger, while other illegal killing was the priority threat in Lebanon and Syria. Our work cannot quantify which threat has the greatest demographic impact on Egyptian Vultures. Nonetheless, because all threats we assessed are relevant for many other migratory birds, our assessment highlights the priority threats that range states need to address to protect migratory birds.

Limit of detection comparison on urine gross alpha/beta, H-3, and P-32 analysis between different liquid scintillation counters.

As part of the Centers for Disease Control and Prevention's post-radiological/nuclear incident response mission, we developed rapid bioassay analytical methods to assess possible human exposure to radionuclides and internal contamination. Liquid scintillation counting (LSC) is a valuable analytical tool for the rapid detection and quantification of gross alpha/beta-emitting radionuclides in urine samples. A key characteristic of this type of bioassay method is its detection sensitivity for the priority threat radionuclides. We evaluated the limit of detection of selected LSC instruments to determine which instrument can be used when low-dose measurement is important.

Prioritizing threat management across terrestrial and freshwater realms for species conservation and recovery

AbstractThe need to manage threats to biodiversity, and to do so cost‐effectively, is urgent. Cross‐realm conservation management is recognized as a cost‐effective approach, but it requires collaboration between agencies and jurisdictions, and local knowledge of anthropogenic threats to biodiversity. With its emphasis on stakeholder engagement and use of structured expert elicitation, Priority Threat Management (PTM) facilitates rapid, cross‐realm planning at the regional scale. We used PTM to identify cost‐effective management strategies with the aim of securing nine ecological groups, comprised of 45 species and one ecological community of conservation concern, across terrestrial and freshwater realms within the Wolastoq|Saint John River watershed in Canada. Under business‐as‐usual, four of nine groups are expected to have >50% probability of persistence over the next 25 years. Investment of $141 million over 25 years in three management strategies could secure seven groups across both realms with >50% probability of persistence. Achieving higher levels of persistence comes at a cost—securing six groups with >60% probability of persistence requires investing $218 million over 25 years in seven strategies. Through a structured, iterative process, whereby stakeholders cooperate to clarify objectives, devise management strategies, and collate data, PTM can support timely and cost‐effective management across multiple realms.

Conservation in heavily urbanized biodiverse regions requires urgent management action and attention to governance

AbstractThroughout history, humans have settled in areas of high biodiversity. Today these areas are home to our biggest urban centers with biodiversity at increasing risk from escalating cumulative threats. Identifying the management strategies to conserve species within such regions, and ensuring effective governance to oversee their implementation, presents enormous challenges. Using a novel Priority Threat Management (PTM) approach that calculates the cost‐effectiveness of conservation action and co‐governance, we discover that the 102 species at risk of local extinction within Canada's most diverse, heavily urbanized coastal region, the Fraser River estuary, require urgent investment in management strategies costing an estimated CAD$381 M over 25 years. Our study also suggests that co‐governance underpins conservation success in urban areas, by increasing the feasibility of management strategies. This study underscores that biodiversity conservation in heavily urbanized areas is not a lost cause but does require strategic planning, attention to governance, and large‐scale investment.

Rapidly building surge capacity within a pandemic response using simulation-based clinical systems testing

IntroductionAs the SARS-CoV-2 virus spread across the globe, hospitals around the USA began preparing for its arrival. Building on previous experience with alternative care sites (ACS) during surge events, Texas...

Prioritizing conservation actions for Pacific salmon in Canada

Abstract Current investment in conservation is insufficient to adequately protect and recover all ecosystems and species. The challenge of allocating limited funds is acute for Pacific salmon Oncorhynchus spp. in Canada, which lack a strategic approach to ensure that resources are spent on actions most likely to cost‐effectively recover diminished populations. We applied the Priority Threat Management framework to prioritize strategies most likely to maximize the number of thriving Pacific salmon populations on the Central Coast of British Columbia, Canada. These included 79 genetically, ecologically and spatially distinct population groups called conservation units (CUs) for five salmon species. This region has high salmon biodiversity and spans the territories of four First Nations: the Heiltsuk, Nuxalk, Kitasoo/Xai'xais and Wuikinuxv. Using structured expert elicitation of Indigenous and other experts, we quantified the estimated benefits, costs and feasibility of implementing 10 strategies. Under a business‐as‐usual scenario (i.e. no additional investments in salmon conservation or management), experts predicted that only one in four CUs would have >50% chance of achieving a thriving status within 20 years. Limiting future industrial development in salmon habitats, which was predicted to safeguard CUs from future declines, was identified as the most cost‐effective strategy. Investment in three strategies: (a) removal of artificial barriers to fish migration, (b) watershed protection and (c) stream restoration—at 11.3M CAD per year—was predicted to result in nearly half (34 of 79) of the CUs having a >60% chance of meeting the conservation objective. If all conservation strategies were implemented, experts estimated a >50% probability of achieving a thriving status for 78 of 79 CUs, at an annual cost of 17.3M CAD. However, even with the implementation of all strategies, most sockeye salmon CUs were unlikely to achieve higher probability targets of reaching the objective. Policy implications. We illustrate how Priority Threat Management can incorporate the perspectives and expertise of Indigenous peoples and other experts to prioritize conservation strategies based on their cost, benefit and feasibility. Implementation of this framework can help safeguard and recover Pacific salmon in Canada, and could also be used to prioritize actions for other conservation issues globally.

Managing Forest Health through Collaboration on the Allegheny High Unglaciated Plateau

Abstract Forests in the High Allegheny Unglaciated Plateau Subsection of Pennsylvania and New York, including the Allegheny National Forest, have been increasingly impacted by an array of native and introduced forest insects, pathogens, plants, and other disturbances for decades. An unbalanced age-class distribution, changing soil nutrient status, seedling establishment issues, droughts, and storm events also threaten forest health and structure. In 2017, the Allegheny National Forest convened a broad cross-section of forest stakeholders to collaboratively assess and prioritize these threats and develop effective strategies to address them. Relying on consensus and shared learning, the Allegheny Forest Health Collaborative assigned priorities and created working groups to address priority threats. This paper describes the collaboration and features a case study of followup, multilandowner work to assign treatment priorities to affected stands and develop silvicultural strategies for stands with poor and decreasing seed source.

A systematic expert‐based assessment of progress and priorities for conservation of the Bengal Florican Houbaropsis bengalensis

AbstractWe used information derived from expert elicitation to measure progress in conservation of the Bengal Florican (Houbaropsis bengalensis) by calculating six metrics, namely: (a) current threat impact, (b) research need, (c) research achievement, (d) management need, (e) management achievement, and (f) percentage threat reduction. We then used the metrics to identify priority threats, namely predation by dogs, hunting, power lines, and vegetation changes caused by human activities. The metrics indicate that although there has been little progress in addressing predation and power lines, reductions in hunting have been achieved and practitioners have a good understanding of how to ameliorate vegetation changes. We assessed conservation needs across all sites that support Bengal Florican, and highlight conservation achievements at Stoung‐Chikreang Bengal Florican Conservation Area (BFCA), Manas National Park and Kaziranga National Park. We used our results to develop a framework for prioritizing collaboration on tackling priority threats. We highlight D'Ering Wildlife Sanctuary in India as one of the highest priority sites for Bengal Florican conservation, and propose that conservation in Stoung‐Chikreang Bengal Florican Conservation Area (BFCA), Manas National Park and Kaziranga National Park must be continued, scaled‐up and good‐practice replicated at Koklabari, Baray BFCA and Koshi Tappu Wildlife Reserve. If these plans are followed, then we believe that priority threats can be adequately addressed and the extinction of Bengal Florican can be prevented.

The intensity of solar radiation in the city of Lviv

The fuel and energy potential of Ukraine is characterized by the scale, multi-component and high value of mineral reserves. Energy saving is one of the main political and economic directions of development in Ukraine. However, in conditions of constant depletion of natural resources, the increase in the cost of oil, changes in climatic conditions due to increased emissions of carbon dioxide, there is an important problem of improving energy efficiency through the use of thermal insulation systems or increasing the use of renewable energy sources.Solar energy is used as an unconventional source of energy. It is also an inexhaustible source of energy for humanity and largely controls theclimate on the planet Earth. For the transformation of solar energy coming to the surface of the planet, special installations have been developed, which are constantly being improved. Thanks to such installations, negative climate change in the future can be stopped. The United Nations considers climate change a priority threat to humanity in the XXI century. Thus, the priority is the development of heat supply and electricity supply from solar energy. The climate change is the important and long-term variation of parameters in the statistical distribution of weather conditions for a long time, so the use of solar energy requires constant updating of data on its volume entering the plane.The paper analyzes the study area of the state of solar radiation, which enters the territory of Ukraine, in particular in the city of Lviv in July.Today there are a number of studies on the level of solar radiation on the territory of Ukraine. In particular, the total solar radiation and the average daily total density of the solar energy flow entering the horizontal plane on the territory of Ukraine under the condition of the clear sky were established [11, 12].In our studies, we obtained data on solar radiation with different points of the world entering the horizontal plane of the solar field in July. The data of solar radiation entering the inclined surface of the solar field, which is set at an angle of 45° relative to the horizon, are analyzed.

Priority Threat Management for biodiversity conservation: A handbook

Abstract Threats to biodiversity and the integrity of ecological systems are escalating globally, both within and outside of protected areas. Decision makers have inadequate resources to manage all threats and typically lack information on the likely outcomes and cost‐effectiveness of possible management strategies. Priority Threat Management (PTM) is an emerging approach designed to address this challenge, by defining and appraising cost‐effective strategies for mitigating threats to biodiversity across regions. The scientific and practical impacts of PTM are increasing, with a growing number of case study applications across the globe. Here, we provide guidance and resource material for conducting the PTM process based on our experience delivering six large‐scale projects across Australia and Canada. Our handbook describes the four stages of PTM: scoping and planning; defining and collecting key elements; analysing the cost‐effectiveness of strategies; and communicating and integrating recommendations. We summarise critical tips, strengths, and limitations and scope for possible enhancements of the approach. Priority Threat Management harnesses scientific and expert‐derived information to prioritise management strategies based on their benefit to biodiversity, management costs and feasibility. The approach involves collaboration with key experts and stakeholders in a region to improve knowledge sharing and conservation support. The PTM approach identifies sets of regional level strategies that together provide the greatest benefits for multiple species under a limited budget, which can be used to inform existing processes for decision‐making. The PTM approach applies some generalisations in management strategies and resolution, in order to address complex challenges. Further developments of the approach include testing in a greater range of socioecological systems with adaptations that cater for multiobjective decisions. Synthesis and applications. Priority Threat Management is a decision science approach that brings people together to define and prioritise strategies for managing threats to biodiversity across broad regions. It delivers a prospectus for investment in the biodiversity of a region that is transparent, repeatable, participatory, and based on the best available information. Our handbook provides the necessary guidance and resources for expanding the Priority Threat Management approach to new locations, contexts, and challenges.

Priority threat management for imperilled species of the Queensland Brigalow Belt

In this report, we present a costed and prioritised set of feasible threat management strategies for protecting 179 of the most threatened native plant and animal species of the Brigalow Belt bioregion, a highly modified biodiversity hotspot covering 20% of Queensland, Australia. The 12 strategies outlined here were designed through a consultation process with 40 experts and stakeholders in biodiversity and land management of the region, using the best available scientific data and expert knowledge.