Tracking the global footprint of fisheries

Although fishing is one of the most widespread activities by which humans harvest natural resources, its global footprint is poorly understood and has never been directly quantified. We processed 22 billion automatic identification system messages and tracked >70,000 industrial fishing vessels from 2012 to 2016, creating a global dynamic footprint of fishing effort with spatial and temporal resolution two to three orders of magnitude higher than for previous data sets. Our data show that industrial fishing occurs in >55% of ocean area and has a spatial extent more than four times that of agriculture. We find that global patterns of fishing have surprisingly low sensitivity to short-term economic and environmental variation and a strong response to cultural and political events such as holidays and closures.

A user-friendly tool to evaluate the effectiveness of no-take marine reserves

Marine reserves are implemented to achieve a variety of objectives, but are seldom rigorously evaluated to determine whether those objectives are met. In the rare cases when evaluations do take place, they typically focus on ecological indicators and ignore other relevant objectives such as socioeconomics and governance. And regardless of the objectives, the diversity of locations, monitoring protocols, and analysis approaches hinder the ability to compare results across case studies. Moreover, analysis and evaluation of reserves is generally conducted by outside researchers, not the reserve managers or users, plausibly thereby hindering effective local management and rapid response to change. We present a framework and tool, called "MAREA", to overcome these challenges. Its purpose is to evaluate the extent to which any given reserve has achieved its stated objectives. MAREA provides specific guidance on data collection and formatting, and then conducts rigorous causal inference analysis based on data input by the user, providing real-time outputs about the effectiveness of the reserve. MAREA's ease of use, standardization of state-of-the-art inference methods, and ability to analyze marine reserve effectiveness across ecological, socioeconomic, and governance objectives could dramatically further our understanding and support of effective marine reserve management.

To what extent can ecosystem services motivate protecting biodiversity?

Society increasingly focuses on managing nature for the services it provides people rather than for the existence of particular species. How much biodiversity protection would result from this modified focus? Although biodiversity contributes to ecosystem services, the details of which species are critical, and whether they will go functionally extinct in the future, are fraught with uncertainty. Explicitly considering this uncertainty, we develop an analytical framework to determine how much biodiversity protection would arise solely from optimising net value from an ecosystem service. Using stochastic dynamic programming, we find that protecting a threshold number of species is optimal, and uncertainty surrounding how biodiversity produces services makes it optimal to protect more species than are presumed critical. We define conditions under which the economically optimal protection strategy is to protect all species, no species, and cases in between. We show how the optimal number of species to protect depends upon different relationships between species and services, including considering multiple services. Our analysis provides simple criteria to evaluate when managing for particular ecosystem services could warrant protecting all species, given uncertainty. Evaluating this criterion with empirical estimates from different ecosystems suggests that optimising some services will be more likely to protect most species than others.

Range contraction enables harvesting to extinction

Economic incentives to harvest a species usually diminish as its abundance declines, because harvest costs increase. This prevents harvesting to extinction. A known exception can occur if consumer demand causes a declining species' harvest price to rise faster than costs. This threat may affect rare and valuable species, such as large land mammals, sturgeons, and bluefin tunas. We analyze a similar but underappreciated threat, which arises when the geographic area (range) occupied by a species contracts as its abundance declines. Range contractions maintain the local densities of declining populations, which facilitates harvesting to extinction by preventing abundance declines from causing harvest costs to rise. Factors causing such range contractions include schooling, herding, or flocking behaviors-which, ironically, can be predator-avoidance adaptations; patchy environments; habitat loss; and climate change. We use a simple model to identify combinations of range contractions and price increases capable of causing extinction from profitable overharvesting, and we compare these to an empirical review. We find that some aquatic species that school or forage in patchy environments experience sufficiently severe range contractions as they decline to allow profitable harvesting to extinction even with little or no price increase; and some high-value declining aquatic species experience severe price increases. For terrestrial species, the data needed to evaluate our theory are scarce, but available evidence suggests that extinction-enabling range contractions may be common among declining mammals and birds. Thus, factors causing range contraction as abundance declines may pose unexpectedly large extinction risks to harvested species.

Attitudes to outcomes measured in clinical trials of cardiovascular prevention

BACKGROUND

Selecting outcome measures in cardiovascular prevention trials should be informed by their importance to selected populations. Major vascular event outcomes are usually prioritized in these trials with considerably less attention paid to cognitive and functional outcomes.

AIM

To examine views on importance of outcome measures used in clinical trials.

DESIGN

Cross-sectional survey.

METHODS

Of 367 individuals approached, 280 (76%) participated: outpatients attending cardiovascular prevention clinics (n = 97), active retirement groups members (n = 75), medical students (n = 108). Participants were asked to rank, in order of importance, outcome measures, which may be included in cardiovascular prevention trials. Results were compared between two groups: <65s (n = 157) and ≥65s (n = 104).

RESULTS

When asked what outcomes were most important to measure in cardiovascular prevention trials, respondents reported: death (31.6%) stroke (28.5%), dementia (26.9%), myocardial infarction (MI) (7.9%) and requiring nursing home (NH) care (5.1%). When asked the most relevant outcomes regarding successful ageing respondents reported; maintaining independence (32.4%), avoiding major illness (24.3%), good family life (23.6%), living as long as possible (15.8%), avoiding NH care (3.1%) and contributing to society (0.8%) as most important. When asked what outcome concerned them most about the future, respondents reported: dementia (32.6%), dependence (30.4%), death (12.8%), stroke (12.5%), cancer (6.2%) requiring NH care (4.8%) and MI (0.7%). Maintaining independence was considered most important in younger and older cohorts.

CONCLUSION

Cognitive and functional outcomes are important patient-relevant outcomes, sometimes more important than major vascular events. Incorporating these outcomes into trials may encourage patient participation and adherence to preventative regimens.

Integrating scientific guidance into marine spatial planning

Marine spatial planning (MSP), whereby areas of the ocean are zoned for different uses, has great potential to reduce or eliminate conflicts between competing management goals, but only if strategically applied. The recent literature overwhelmingly agrees that including stakeholders in these planning processes is critical to success; but, given the countless alternative ways even simple spatial regulations can be configured, how likely is it that a stakeholder-driven process will generate plans that deliver on the promise of MSP? Here, we use a spatially explicit, dynamic bioeconomic model to show that stakeholder-generated plans are doomed to fail in the absence of strong scientific guidance. While strategically placed spatial regulations can improve outcomes remarkably, the vast majority of possible plans fail to achieve this potential. Surprisingly, existing scientific rules of thumb do little to improve outcomes. Here, we develop an alternative approach in which models are used to identify efficient plans, which are then modified by stakeholders. Even if stakeholders alter these initial proposals considerably, results hugely outperform plans guided by scientific rules of thumb. Our results underscore the importance of spatially explicit dynamic models for the management of marine resources and illustrate how such models can be harmoniously integrated into a stakeholder-driven MSP process.

Close the high seas to fishing?

The world's oceans are governed as a system of over 150 sovereign exclusive economic zones (EEZs, ∼42% of the ocean) and one large high seas (HS) commons (∼58% of ocean) with essentially open access. Many high-valued fish species such as tuna, billfish, and shark migrate around these large oceanic regions, which as a consequence of competition across EEZs and a global race-to-fish on the HS, have been over-exploited and now return far less than their economic potential. We address this global challenge by analyzing with a spatial bioeconomic model the effects of completely closing the HS to fishing. This policy both induces cooperation among countries in the exploitation of migratory stocks and provides a refuge sufficiently large to recover and maintain these stocks at levels close to those that would maximize fisheries returns. We find that completely closing the HS to fishing would simultaneously give rise to large gains in fisheries profit (>100%), fisheries yields (>30%), and fish stock conservation (>150%). We also find that changing EEZ size may benefit some fisheries; nonetheless, a complete closure of the HS still returns larger fishery and conservation outcomes than does a HS open to fishing.

Conservation markets for wildlife management with case studies from whaling

Although market-based incentives have helped resolve many environmental challenges, conservation markets still play a relatively minor role in wildlife management. Establishing property rights for environmental goods and allowing trade between resource extractors and resource conservationists may offer a path forward in conserving charismatic species like whales, wolves, turtles, and sharks. In this paper, we provide a conceptual model for implementing a conservation market for wildlife and evaluate how such a market could be applied to three case studies for whales (minke [Balaenoptera acutorostrata], bowhead [Balaena mysticetus], and gray [Eschrictius robustus]). We show that, if designed and operated properly, such a market could ensure persistence of imperiled populations, while simultaneously improving the welfare of resource harvesters.

Encourage sustainability by giving credit for marine protected areas in seafood certification

Sarah Lester et al. argue that sustainable seafood certification programs are missing a critical opportunity by failing to provide credit for marine protected areas. Fixing this oversight will improve the leverage of certification programs to drive sustainable fishing, with significant benefits to fish and fisheries.

A general business model for marine reserves

Marine reserves are an effective tool for protecting biodiversity locally, with potential economic benefits including enhancement of local fisheries, increased tourism, and maintenance of ecosystem services. However, fishing communities often fear short-term income losses associated with closures, and thus may oppose marine reserves. Here we review empirical data and develop bioeconomic models to show that the value of marine reserves (enhanced adjacent fishing + tourism) may often exceed the pre-reserve value, and that economic benefits can offset the costs in as little as five years. These results suggest the need for a new business model for creating and managing reserves, which could pay for themselves and turn a profit for stakeholder groups. Our model could be expanded to include ecosystem services and other benefits, and it provides a general framework to estimate costs and benefits of reserves and to develop such business models.

Eco-label conveys reliable information on fish stock health to seafood consumers

Concerns over fishing impacts on marine populations and ecosystems have intensified the need to improve ocean management. One increasingly popular market-based instrument for ecological stewardship is the use of certification and eco-labeling programs to highlight sustainable fisheries with low environmental impacts. The Marine Stewardship Council (MSC) is the most prominent of these programs. Despite widespread discussions about the rigor of the MSC standards, no comprehensive analysis of the performance of MSC-certified fish stocks has yet been conducted. We compared status and abundance trends of 45 certified stocks with those of 179 uncertified stocks, finding that 74% of certified fisheries were above biomass levels that would produce maximum sustainable yield, compared with only 44% of uncertified fisheries. On average, the biomass of certified stocks increased by 46% over the past 10 years, whereas uncertified fisheries increased by just 9%. As part of the MSC process, fisheries initially go through a confidential pre-assessment process. When certified fisheries are compared with those that decline to pursue full certification after pre-assessment, certified stocks had much lower mean exploitation rates (67% of the rate producing maximum sustainable yield vs. 92% for those declining to pursue certification), allowing for more sustainable harvesting and in many cases biomass rebuilding. From a consumer’s point of view this means that MSC-certified seafood is 3–5 times less likely to be subject to harmful fishing than uncertified seafood. Thus, MSC-certification accurately identifies healthy fish stocks and conveys reliable information on stock status to seafood consumers.

Matching spatial property rights fisheries with scales of fish dispersal

Regulation of fisheries using spatial property rights can alleviate competition for high-value patches that hinders economic efficiency in quota-based, rights-based, and open-access management programs. However, efficiency gains erode when delineation of spatial rights constitutes incomplete ownership of the resource, thereby degrading its local value and promoting overexploitation. Incomplete ownership may be particularly prevalent in the spatial management of mobile fishery species. We developed a game-theoretic bioeconomic model of spatial property rights representing territorial user rights fisheries (TURF) management of nearshore marine fish and invertebrate species with mobile adult and larval life history stages. Strategic responses by fisheries in neighboring management units result in overexploitation of the stock and reduced yields for each fishery compared with those attainable without resource mobility or with coordination or sole control in fishing effort. High dispersal potential of the larval stage, a common trait among nearshore fishery species, coupled with scaling of management units to only capture adult mobility, a common characteristic of many nearshore TURF programs, in particular substantially reduced stock levels and yields. In a case study of hypothetical TURF programs of nearshore fish and invertebrate species, management units needed to be tens of kilometers in alongshore length to minimize larval export and generate reasonable returns to fisheries. Cooperation and quota regulations represent solutions to the problem that need to be quantified in cost and integrated into the determination of the acceptability of spatial property rights management of fisheries.

Effect of pharmaceutical pre-assessment on post-operative interventions

Focal points

Rebuilding Global Fisheries

After a long history of overexploitation, increasing efforts to restore marine ecosystems and rebuild fisheries are under way. Here, we analyze current trends from a fisheries and conservation perspective. In 5 of 10 well-studied ecosystems, the average exploitation rate has recently declined and is now at or below the rate predicted to achieve maximum sustainable yield for seven systems. Yet 63% of assessed fish stocks worldwide still require rebuilding, and even lower exploitation rates are needed to reverse the collapse of vulnerable species. Combined fisheries and conservation objectives can be achieved by merging diverse management actions, including catch restrictions, gear modification, and closed areas, depending on local context. Impacts of international fleets and the lack of alternatives to fishing complicate prospects for rebuilding fisheries in many poorer regions, highlighting the need for a global perspective on rebuilding marine resources.