Other effective area-based conservation measures (OECMs) are sites that deliver effective biodiversity outcomes irrespective of their management objectives. These areas are widely expected to play an important role in efforts to protect 30% of Earth by 2030. Despite general guidance to support screening sites against the formal criteria to be OECMs, progress recognizing sites has been limited. To advance the ability to identify OECMs, we developed a questionnaire that translates the components of the broad formal guidance into statements that experts can use to screen potential OECMs. Twenty-eight local experts used the questionnaire to evaluate a large global sample of 81 sites. Most sites evaluated were largely in good condition and had the potential to achieve conservation outcomes, but none met the criteria to be considered OECMs. The most common challenges are related to threat management, adequate resourcing, and the ability to demonstrate that governance and management are achieving effective and sustained conservation outcomes. Based on the formal International Union for Conservation of Nature guidance, sites that only partially meet the relevant criteria remain candidate OECMs. Our questionnaire provides a nuanced way to assess OECMs that can help identify what support sites need to meet the necessary criteria. With effective long-term conservation outcomes unable to be demonstrated for so many important conservation areas, our findings raise important questions about how to ensure area-based conservation promotes positive and sustained outcomes for biodiversity.

The Kunming-Montreal Global Biodiversity Framework (GBF) will become the most important multilateral agreement to guide biodiversity conservation actions globally over the coming decades. An ecosystem goal and various targets for maintaining integrity, restoring degraded ecosystems, and achieving representation in conservation areas feature throughout the GBF. Here, we propose an operational framework that combines disparate information on ecosystem type, extent, integrity, levels of protection, and risk of collapse to support the identification of irreplaceable ‘Critical Ecosystem Areas’ (CEAs), to help advance these ecosystem targets. The framework classifies each component ecosystem based on its integrity, importance in ensuring no ecosystem collapse and its relative value to achieving representation if protected. These CEAs are immediate conservation opportunities, given that they achieve multiple ecosystem goals and targets in the GBF. We showcase its application using Myanmar’s forested ecosystems as a case study and argue that it could be immediately used across all terrestrial ecosystems.

ABSTRACT Other effective area-based conservation measures (OECMs) have expanded area-based conservation to recognize sites that deliver effective biodiversity outcomes even if not managed for conservation. Yet our ability to identify sites likely to qualify as OECMs remains limited. To address this gap, we established and tested a set of indicators to judge whether sites meet the essential criteria to be considered OECMs, evaluating a large, global sample of 173 important conservation areas: 81 potential OECMs and 92 nearby protected areas. We found that most potential OECMs were largely in good condition with the potential to achieve conservation outcomes, but none currently met all the OECM criteria. Formally designated protected areas in our dataset performed better but the majority also failed the criteria. With so many important conservation areas unable to deliver effective conservation outcomes, our findings raise important questions about how to ensure area-based conservation promotes positive and sustained outcomes for biodiversity.

Protected area (PA) sustainability is challenged worldwide by legal downgrading, downsizing, and degazettement (PADDD). National and local case studies of ecologically destructive PADDD events provide useful insights that may help respond to or prevent future events. Using information from legal documents and expert input, we identified 37 PADDD events that affected two adjacent PAs in northeastern Cambodia differently despite similar economic, environmental, and social conditions. Important differences in local context led to the eventual degazettement (100% loss) of one PA and downsizing (10.49% loss) of the other, the rest of which remains protected. This case study confirms the contribution of secure Indigenous land tenure to durable conservation governance and demonstrates the importance of investing in site-level capacity to ensure that social and ecological conditions are monitored and proposed PADDD events can be successfully challenged.

Informal gold mining (IGM) is a major driver of deforestation and source of global mercury emissions. Policy makers may seek to control the spread of IGM by enforcing rules and/or providing alternative livelihoods. We investigated the dynamics and drivers of IGM in northern Myanmar to shed light on the conditions needed for alternative livelihood and enforcement interventions to succeed. We surveyed 226 respondents who practiced mining and/or farming. We found that mining and agriculture provided complementary livelihoods for many respondents as they met different livelihood needs, and that many of the miners were economic migrants. Livelihood‐based interventions based on agriculture/plantations—as currently planned by the regional government—are thus unlikely to provide true substitutes. The willingness of migrant miners to move under different economic circumstances suggests that livelihood‐based interventions are unlikely to scale well—mining may simply be displaced to other regions, or new migrants might replace old migrants. We estimated that current enforcement efforts were insufficient and that a much higher level of enforcement—either constant presence of enforcement officials at each informal mining site, or confiscating equipment every month—would be required to make informal mining unprofitable. Enforcement effectiveness was further undermined by corruption in the guise of informal payments to local authorities. Our study is the first to estimate costs that enforcement imposes and the level of enforcement required to deter informal gold mining, and adds to the growing body of evidence that enforcement and alternative livelihood approaches alone are unlikely to deter informal gold mining.

Expansion of Hevea brasiliensis rubber plantations is a resurgent driver of deforestation, carbon emissions, and biodiversity loss in Southeast Asia. Southeast Asian rubber extent is massive, equivalent to 67% of oil palm, with rapid further expansion predicted. Results-based carbon finance could dis-incentivise forest conversion to rubber, but efficacy will be limited unless payments match, or at least approach, the costs of avoided deforestation. These include opportunity costs (timber and rubber profits), plus carbon finance scheme setup (transaction) and implementation costs. Using comprehensive Cambodian forest data, exploring scenarios of selective logging and conversion, and assuming land-use choice is based on net present value, we find that carbon prices of $30-$51 per tCO2 are needed to break even against costs, higher than those currently paid on carbon markets or through carbon funds. To defend forests from rubber, either carbon prices must be increased, or other strategies are needed, such as corporate zero-deforestation pledges, and governmental regulation and enforcement of forest protection.

Political and economic transitions have had substantial impacts on forest conservation. Where transitions are underway or anticipated, historical precedent and methods for systematically assessing future trends should be used to anticipate likely threats to forest conservation and design appropriate and prescient policy measures to counteract them. Myanmar is transitioning from an authoritarian, centralized state with a highly regulated economy to a more decentralized and economically liberal democracy and is working to end a long-running civil war. With these transitions in mind, we used a horizon-scanning approach to assess the 40 emerging issues most affecting Myanmar's forests, including internal conflict, land-tenure insecurity, large-scale agricultural development, demise of state timber enterprises, shortfalls in government revenue and capacity, and opening of new deforestation frontiers with new roads, mines, and hydroelectric dams. Averting these threats will require, for example, overhauling governance models, building capacity, improving infrastructure- and energy-project planning, and reforming land-tenure and environmental-protection laws. Although challenges to conservation in Myanmar are daunting, the political transition offers an opportunity for conservationists and researchers to help shape a future that enhances Myanmar's social, economic, and environmental potential while learning and applying lessons from other countries. Our approach and results are relevant to other countries undergoing similar transitions.

A reliable estimate of population size is of paramount importance for making management decisions on species of conservation significance that may be impacted during development. The western ringtail possum (Pseudocheirus occidentalis) is regularly encountered during urban development and is the subject of numerous surveys to estimate its abundance. A variety of techniques have been used for this species with mixed results. This paper reports on a case study using distance sampling to estimate density of P. occidentalis in a small habitat remnant near Busselton, Western Australia. Density estimates obtained were within the range of previous studies of this species and we suggest that this technique should be employed in future surveys to improve the accuracy of population estimates for this species before development.