Conservation Letters

Protected areas (PAs) represent a cornerstone of efforts to safeguard biodiversity, and if effective should reduce threats to biodiversity. We present the most comprehensive assessment of threats to terrestrial PAs, based on in situ data from 1,961 PAs across 149 countries, assessed by PA managers and local stakeholders. Unsustainable hunting was the most commonly reported threat and occurred in 61% of all PAs, followed by disturbance from recreational activities occurring in 55%, and natural system modifications from fire or its suppression in 49%. The number of reported threats was lower in PAs with greater remoteness, higher control of corruption, and lower human development scores. The main reported threats in developing countries were linked to overexploitation for resource extraction, while negative impacts from recreational activities dominated in developed countries. Our results show that many of the most serious threats to PAs are difficult to monitor with remote sensing, and highlight the importance of in situ threat data to inform the implementation of more effective biodiversity conservation in the global protected area estate.

Globally, annual expenditure on ecological restoration of degraded areas for habitat improvement and biodiversity conservation is approximately $18bn. Seed farming of native plant species is crucial to meet restoration goals, but may be stymied by the disconnection of academic research in seed science and the lack of effective policies that regulate native seed production/supply. To illustrate this problem, we identified 1,122 plant species important for European grasslands of conservation concern and found that only 32% have both fundamental seed germination data available and can be purchased as seed. The “restoration species pool,”or set of species available in practice, acts as a significant biodiversity selection filter for species use in restoration projects. For improvement, we propose: (1) substantial expansion of research and development on native seed quality, viability, and production; (2) open‐source knowledge transfer between sectors; and (3) creation of supportive policy intended to stimulate demand for biodiverse seed.

Decision makers and land managers are increasingly required to manage landscapes for multiple purposes and benefits. However, despite progress in the development of frameworks linking natural capital to the provision of ecosystem services and human benefits there remains little guidance for how management interventions can improve ecosystem service provision. As ecosystem services cannot be directly influenced, interventions need to be directed toward natural capital stocks. We provide a framework that explicitly links natural capital stocks to ecosystem service provision and identify manageable attributes of natural capital stocks as the critical intervention point. A structured decision making process based on our framing of the ecosystem services concept can facilitate its application on the ground.

The absence of boreal forests from global policy agendas on sustainable development and climate change mitigation represents a massive missed opportunity for environmental protection. The boreal zone contains some of the world's largest pools of terrestrial carbon that, if not safeguarded from a conversion to a net source of greenhouse gases, could seriously exacerbate global climate change. At the same time, boreal countries have a strong tradition of forest management—expertise that could be effectively leveraged toward global and national carbon mitigation targets and sustainable development. Current obstacles against such contributions include weak incentives for carbon sequestration and a reluctance to embrace change by forest managers and policy makers. We discuss possible solutions to overcome these obstacles, including the improvement of ineffective incentives, the development of alternative forest management strategies, and the need to maintain ecosystem resilience through the pursuit of policy and management options.

Governments have committed to conserving ≥17% of terrestrial and ≥10% of marine environments globally, especially “areas of particular importance for biodiversity” through “ecologically representative” Protected Area (PA) systems or other “area‐based conservation measures”, while individual countries have committed to conserve 3–50% of their land area. We estimate that PAs currently cover 14.6% of terrestrial and 2.8% of marine extent, but 59–68% of ecoregions, 77–78% of important sites for biodiversity, and 57% of 25,380 species have inadequate coverage. The existing 19.7 million km² terrestrial PA network needs only 3.3 million km² to be added to achieve 17% terrestrial coverage. However, it would require nearly doubling to achieve, cost‐efficiently, coverage targets for all countries, ecoregions, important sites, and species. Poorer countries have the largest relative shortfalls. Such extensive and rapid expansion of formal PAs is unlikely to be achievable. Greater focus is therefore needed on alternative approaches, including community‐ and privately managed sites and other effective area‐based conservation measures.

Global areal protection targets have driven a dramatic expansion of the marine protected area (MPA) estate. We analyzed how cost‐effective global MPA expansion has been since the inception of the first global target (set in 1982) in achieving ecoregional representation. By comparing spatial patterns of MPA expansion against optimal MPA estates using the same expansion rates, we show the current MPA estate is both expensive and ineffective. Although the number of ecoregions represented tripled and 12.7% of national waters was protected, 61% of ecoregions and 81% of countries are not 10% protected. Only 10.3% of the national waters of the world would be sufficient to protect 10% of each ecoregion if MPA growth since 1982 strategically targeted underrepresented ecoregions. Unfortunately 16.3% of national waters are required for the same representative target if systematic protection started in 2016 (an extra 3.6% on top of 12.7%). To avoid the high costs of adjusting increasingly biased MPA systems, future efforts should embrace target‐driven systematic conservation planning.

Coastal marine ecosystems rank among the most productive ecosystems on earth but are also highly threatened by the exposure to both ocean‐ and land‐based human activities. Spatially explicit information on the distributions of land‐based impacts is critical for managers to identify where the effects of land‐based activities on ecosystem condition are greatest and, therefore, where they should prioritize mitigation of land‐based impacts. Here, we quantify the global cumulative impact of four of the most pervasive land‐based impacts on coastal ecosystems—nutrient input, organic and inorganic pollution, and the direct impact of coastal populations (e.g., coastal engineering and trampling)—and identify hotspots of land‐based impact using a variety of metrics. These threat hotspots were primarily in Europe and Asia, with the top three adjacent to the Mississippi, Ganges, and Mekong rivers. We found that 95% of coastal and shelf areas (<200 m depth) and 40% of the global coastline experience little to no impact from land‐based human activities, suggesting that marine conservation and resource management in these areas can focus on managing current ocean activities and preventing future spread of land‐based stressors. These results provide guidance on where coordination between marine and terrestrial management is most critical and where a focus on ocean‐based impacts is instead needed.

Green labeling of products that have been produced sustainably is an emerging tool of the environmental movement. A prominent example is the Forest Stewardship Council, which certifies timber that is harvested to manage and maintain forests defined as having High Conservation Value (HCV). The criteria for HCV are now being applied to four rapidly expanding crops in the tropics: oil palm, soy, sugarcane, and cacao. However, these criteria do not provide adequate protection for biodiversity when applied to agriculture. The only criterion that provides blanket protection to forests is one that protects large expanses of habitat (≥20,000–500,000 ha, depending on the country). Absent of other HCVs, the collective clearing of forest patches below these thresholds could result in extensive deforestation that would be sanctioned with a green label. Yet such forest patches retain much biodiversity and provide connectivity within the agricultural matrix. An examination of forest fragments in biodiverse countries across the tropics shows that future agricultural demand can be met by clearing only forest patches below a 1,000 ha threshold. We recommend the development of a new HCV criterion that recognizes the conservation value of habitat patches within the agricultural matrix and that protects patches above 1,000 ha.

Land‐use change is a major driver of tropical biodiversity declines. The “High Conservation Value” (HCV) approach aims to protect critical environmental and social values in production landscapes, and is a common feature of many voluntary certification schemes (e.g., Forest Stewardship Council, Roundtable on Sustainable Palm Oil). Despite the popularity of the HCV approach within forestry and agriculture production systems, it is little known in academia and the scientific evidence base supporting it is not well developed. By raising the profile of the HCV approach, we hope to instigate new research to examine the impact of the HCV approach on biodiversity conservation. We argue for better knowledge exchange between scientists, policy makers, and HCV users, sharing of information, and consideration of the practical constraints within which HCV users and commodity producers operate. Given the continuing loss and degradation of tropical rainforests, such strategies are required urgently to reduce biodiversity losses in production landscapes.

Much tropical biodiversity resides in forests managed by timber, mining, and plantation companies. These companies can determine the local persistence of many species and have considerable implications for global conservation outcomes. Many companies are willing to invest in improved management as long as this does not undermine their business—indeed accessing green markets often makes commercial sense. Compliance with common standards of good commercial practice requires identification of all species of conservation significance which occur within their areas of management responsibility. But, as we demonstrate, it is impossible for companies to do this comprehensively. Such demands are often counterproductive in that they alienate those who might otherwise be willing to improve. Given the finite resources available for achieving conservation outcomes, we need to trade off data collection against other costs. To encourage adoption and implementation of conservation friendly practices requires incentives, not technical and financial obstacles. We challenge conservation biologists to reconsider the realities of good forest management, and provide pragmatic guidance for business compatible conservation. Until we engage more effectively with commercial interests, opportunities for improved conservation outcomes will be wasted.