Applying habitat and population-density models to land-cover time series to inform IUCN Red List assessments

The IUCN (International Union for Conservation of Nature) Red List categories and criteria are the most widely used framework for assessing the relative extinction risk of species. The criteria are based on quantitative thresholds relating to the size, trends, and structure of species’ distributions and populations. However, data on these parameters are sparse and uncertain for many species and unavailable for others, potentially leading to their misclassification or classification as data deficient. We devised an approach that combines data on land-cover change, species-specific habitat preferences, population abundance, and dispersal distance to estimate key parameters (extent of occurrence, maximum area of occupancy, population size and trend, and degree of fragmentation) and hence predict IUCN Red List categories for species. We applied our approach to nonpelagic birds and terrestrial mammals globally (∼15,000 species). The predicted categories were fairly consistent with published IUCN Red List assessments, but more optimistic overall. We predicted 4.2% of species (467 birds and 143 mammals) to be more threatened than currently assessed and 20.2% of data deficient species (10 birds and 114 mammals) to be at risk of extinction. Incorporating the habitat fragmentation subcriterion reduced these predictions 1.5–2.3% and 6.4–14.9% (depending on the quantitative definition of fragmentation) for threatened and data deficient species, respectively, highlighting the need for improved guidance for IUCN Red List assessors on the application of this aspect of the IUCN Red List criteria. Our approach complements traditional methods of estimating parameters for IUCN Red List assessments. Furthermore, it readily provides an early-warning system to identify species potentially warranting changes in their extinction-risk category based on periodic updates of land-cover information. Given our method relies on optimistic assumptions about species distribution and abundance, all species predicted to be more at risk than currently evaluated should be prioritized for reassessment.     

Motivating landowners to recruit neighbors for private land conservation

Encouraging motivated landowners to not only engage in conservation action on their own property but also to recruit others may enhance effectiveness of conservation on private lands. Landowners may only engage in such recruitment if they believe their neighbors care about the conservation issue, will positively respond to their conservation efforts, and are likely to take action for the conservation cause. We designed a series of microinterventions that can be added to community meetings to change these beliefs to encourage landowner engagement in recruitment of others. The microinterventions included neighbor discussion, public commitment making, collective goal setting, and increased observability of contributions to the conservation cause. In a field experiment, we tested whether adding microinterventions to traditional knowledge-transfer outreach meetings changed those beliefs so as to encourage landowners in Hawaii to recruit their neighbors for private lands conservation. We delivered a traditional outreach meeting about managing the invasive little fire ant (Wasmannia auropunctata) to 5 communities and a traditional outreach approach with added microinterventions to 5 other communities. Analysis of pre- and post-surveys of residents showed that compared with the traditional conservation outreach approach, the microinterventions altered a subset of beliefs that landowners had about others. These microinterventions motivated reputationally minded landowners to recruit and coordinate with other residents to control the invasive fire ant across property boundaries. Our results suggest integration of these microinterventions into existing outreach approaches will encourage some landowners to facilitate collective conservation action across property boundaries.     

Evaluation of pay-for-release conservation incentives for unintentionally caught threatened species

In the developing world, the exploitation of threatened species jeopardizes their permanence in the wild. Because not all captures are intentional, for instance when capture methods have low selectivity, pressure on these species may be lessened by releasing living incidentally caught animals. However, it is often unrealistic to expect people to voluntarily do so because it means foregoing the benefits of resource extraction. Financial incentives for such animal release may foster conservation objectives. Reducing human–animal conflicts, protecting natural habitat, and conserving nests of threatened species are examples of conservation benefits that can be built on financial reward systems. However, incentives aiming to protect unintentionally captured threatened species are scarce. We considered pay for release, a type of ecosystem-service payment designed to foster the release of incidentally captured threatened species. We aimed to determine the best conditions to implement this scheme, its potential benefits (e.g., incentivizing the release of threatened species), and pitfalls and priority research needs (e.g., required conditions for pay for release to work) to show that its global applicability is possible. Given that approaches solely based on education and law enforcement may be ineffective under some circumstances, we argue that pay for release can protect incidentally captured endangered species if used under conditions conducive for its success. When local participants’ intrinsic motivation for conservation is weak, but the release of incidentally live-caught animals into their habitats is readily achievable, pay-for-release schemes could jump start urgently needed conservation efforts against indiscriminate animal harvesting.     

Conservation practitioners’ understanding of how to manage evolutionary processes

Both academics and practitioners consider a lack of knowledge about evolutionary theory to be a general barrier to effectively managing genetic diversity. However, it is challenging to judge practitioners’ level of understanding and how this influences their management decisions. Knowledge built through experience may be difficult for practitioners to articulate, but could nonetheless result in appropriate management strategies. To date, researchers have assessed only the explicit (formal) knowledge practitioners have of evolutionary concepts. To explore practitioners’ understanding of evolutionary concepts, it is necessary to consider how they might apply explicit and implicit knowledge to their management decisions. Using an online survey, we asked Australian practitioners to respond to 2 common management scenarios in which there is strong evidence that managing genetic diversity can improve outcomes: managing small, isolated populations and sourcing seeds for restoration projects. In describing their approach to these scenarios, practitioners demonstrated a stronger understanding of the effective management of genetic diversity than the definitions of the relevant concepts. However, their management of genetic diversity within small populations was closer to best practice than for restoration projects. Moreover, the risks practitioners described in implementing best practice management were more likely to affect their approach to restoration than translocation projects. These findings provide evidence that strategies to build the capacity of practitioners to manage genetic diversity should focus on realistic management scenarios. Given that practitioners recognize the importance of adapting their practices and the strong evidence for the benefits of actively managing genetic diversity, there is hope that better engagement by evolutionary biologists with practitioners could facilitate significant shifts toward evolutionarily enlightened management.     

Public views about editing genes in wildlife for conservation

Developments in CRISPR-based gene-editing technologies have generated a growing number of proposals to edit genes in wildlife to meet conservation goals. As these proposals have attracted greater attention, controversies have emerged among scientists and stakeholder groups over potential consequences and ethical implications of gene editing. Responsible governance cannot occur without consulting broader publics, yet little effort has been made to systematically assess public understandings and beliefs in relation to this new area of applied genetic engineering. We analyzed data from a survey of U.S. adults (n = 1600), collected by YouGov, and that examined respondents’ concerns about gene editing in animal and plant wildlife and how those concerns are shaped by cultural dispositions toward science and beliefs about the appropriateness of intervening in nature at the genetic level. On average, respondents perceived more risk than benefit in using these tools. Over 70% agreed that gene editing in wildlife could be “easily used for the wrong purposes.” When evaluating the moral acceptability of gene editing in wildlife, respondents evaluated applications to improve survival in endangered wildlife as more morally acceptable than applications to decrease abundance in a population or eliminate a population. Belief in the authority of scientific knowledge was positively related to favorable views of the benefits, risks, and moral acceptability of editing genes in wildlife. The belief that editing genes in wildlife inappropriately intervenes in nature predicted relatively more concern about risks and moral acceptability and skepticism about benefits. Given high levels of concern and skepticism about gene editing in wildlife for conservation among the U.S. public, a take-it-slow approach to making decisions about when or whether to use these tools is advisable. Early opinions, including those uncovered in this study, are likely to be provisional. Thus, consulting the public should be an ongoing process.     

Understanding and minimizing environmental impacts of the Belt and Road Initiative

China's Belt and Road Initiative (BRI) sets to create connections and build infrastructure across Eurasia, Asia, and parts of the African continent in its initial phase and is the largest infrastructure project of all time. Any infrastructure project on this scale will necessarily pass through ecofragile regions and key biodiversity areas (KBAs). This creates an imperative to identify possible areas of impact and probable effects on conservation values to facilitate adaptive planning and to mitigate, minimize, or avoid impacts. Using the highest resolution route maps of the BRI available, I overlaid the proposed road and rail routes on KBAs, protected areas, and predicted biodiversity hotspots for over 4138 animal and 7371 plant species. I also assessed the relationship between the proposed route with the distribution of mines across BRI countries and the proportion of deforestation and forest near routes. Infrastructure, especially mining, was clustered near the proposed route; thus, construction and development along the route may increase the size and number of mines. Up to 15% of KBAs were within 1 km of proposed railways. Thus, planned and probable development along the routes may pose a significant risk to biodiversity, especially because the majority of KBAs are unprotected. Many biodiversity hotspots for different taxa were near the route. These hotspots varied between taxa, making systematic management and environmental impact assessments an effective strategy for at least some taxa. A combination of planning and mitigation strategies will likely be necessary to protect the most important areas for biodiversity proximal to development, especially in currently unprotected KBAs and other regions that need protection. A fuller assessment of trade-offs between conservation and other values will be necessary to make good decisions for each project and site being developed, including potentially modifying parts of the route to minimize impacts. Modification or foregoing of infrastructure may be needed if stakeholders consider the conservation costs too high.     

Reserve design to optimize functional connectivity and animal density

Ecological distance-based spatial capture–recapture models (SCR) are a promising approach for simultaneously estimating animal density and connectivity, both of which affect spatial population processes and ultimately species persistence. We explored how SCR models can be integrated into reserve-design frameworks that explicitly acknowledge both the spatial distribution of individuals and their space use resulting from landscape structure. We formulated the design of wildlife reserves as a budget-constrained optimization problem and conducted a simulation to explore 3 different SCR-informed optimization objectives that prioritized different conservation goals by maximizing the number of protected individuals, reserve connectivity, and density-weighted connectivity. We also studied the effect on our 3 objectives of enforcing that the space-use requirements of individuals be met by the reserve for individuals to be considered conserved (referred to as home-range constraints). Maximizing local population density resulted in fragmented reserves that would likely not aid long-term population persistence, and maximizing the connectivity objective yielded reserves that protected the fewest individuals. However, maximizing density-weighted connectivity or preemptively imposing home-range constraints on reserve design yielded reserves of largely spatially compact sets of parcels covering high-density areas in the landscape with high functional connectivity between them. Our results quantify the extent to which reserve design is constrained by individual home-range requirements and highlight that accounting for individual space use in the objective and constraints can help in the design of reserves that balance abundance and connectivity in a biologically relevant manner.     

Site-selection bias and apparent population declines in long-term studies

Detecting population declines is a critical task for conservation biology. Logistical difficulties and the spatiotemporal variability of populations make estimation of population declines difficult. For statistical reasons, estimates of population decline may be biased when study sites are chosen based on abundance of the focal species. In this situation, apparent population declines are likely to be detected even if there is no decline. This site-selection bias is mentioned in the literature but is not well known. We used simulations and real population data to examine the effects of site-selection biases on inferences about population trends. We used a left-censoring method to detect population-size patterns consistent with site-selection bias. The site-selection bias is an important consideration for conservation biologists, and we offer suggestions for minimizing or mitigating it in study design and analysis. Article impact statement: Estimates of population declines are biased if studies begin in large populations, and time-series data show a signature of such an effect.     

稻秆负荷与pH对稻秆厌氧发酵产酸系统启动过程的影响

为探讨稻秆负荷（即稻秆VS/污泥VSS）与发酵pH对稻秆厌氧发酵产酸系统启动过程产挥发性脂肪酸（VFAs）效果的影响,利用厌氧搅拌罐反应系统考察在不同的稻秆负荷（0.556、0.945、1.334和1.724 g/g）和不同的发酵pH（8.0、9.0和10.0）启动运行条件下的产酸性能,并分析了系统启动过程产酸与稻秆主要成分降解之间的关系。实验结果表明,VFAs浓度随稻秆负荷提高而增大,随发酵pH的升高而降低;发酵18 d时,发酵pH为9.0时,稻秆负荷1.334 g/g的产酸效果最好,VFAs浓度与稻秆产酸量分别为4 385.10 mg/L和2.19 gVFAs/g稻秆,此时半纤维素、纤维素和酸性洗涤木质素降解率分别为32.69%、22.53%和6.40%;稻秆负荷为0.945 g/g条件下,VFAs浓度在pH为8.0时达到最高值4 409.51 mg/L,此时稻秆降解量也最多,半纤维素、纤维素和酸性洗涤木质素降解率分别为28.60%、47.32%和22.69%。研究表明,稻秆负荷与发酵pH通过影响稻秆半纤维素、纤维素和木质素的降解影响稻秆厌氧发酵产酸的进程和效果。