Given the short time-frame to limit global warming, and the current emissions gap, it is critical to prioritise mitigation actions. To date, scant attention has been paid to the mitigation benefits of primary forest protection. We estimated tropical forest ecosystem carbon stocks and flows. The ecosystem carbon stock of primary tropical forests is estimated at 141–159 Pg C (billion tonnes of carbon) which is some 49–53% of all tropical forest carbon, the living biomass component of which alone is 91–103% of the remaining carbon budget to limit global warming to below 1.5 degrees above pre-industrial levels. Furthermore, tropical forests have ongoing sequestration rates 0.47–1.3 Pg C yr⁻¹, equivalent to 8–13% of annual global anthropogenic CO₂ (carbon dioxide) emissions. We examined three main forest-based strategies used in the land sector—halting deforestation, increasing forest restoration and improving the sustainable management of production forests. The mitigation benefits of primary forest protection are contingent upon how degradation is defined and accounted for, while those from restoration also depend on how restoration is understood and applied. Through proforestation, reduced carbon stocks in secondary forests can regrow to their natural carbon carrying capacity or primary forest state. We evaluated published data from studies comparing logged and unlogged forests. On average, primary forests store around 35% more carbon. While comparisons are confounded by a range of factors, reported biomass carbon recovery rates were from 40 to 100+ years. There is a substantive portfolio of forest-based mitigation actions and interventions available to policy and decision-makers, depending on national circumstances, in addition to SFM and plantation focused approaches, that can be grouped into four main strategies: protection; proforestation, reforestation and restoration; reform of guidelines, accounting rules and default values; landscape conservation planning. Given the emissions gap, mitigation strategies that merely reduce the rate of emissions against historic or projected reference levels are insufficient. Mitigation strategies are needed that explicitly avoid emissions where possible as well as enabling ongoing sequestration.

Conservation funding is currently limited; cost‐effective conservation solutions are essential. We suggest that the thousands of field stations worldwide can play key roles at the frontline of biodiversity conservation and have high intrinsic value. We assessed field stations’ conservation return on investment and explored the impact of COVID‐19. We surveyed leaders of field stations across tropical regions that host primate research; 157 field stations in 56 countries responded. Respondents reported improved habitat quality and reduced hunting rates at over 80% of field stations and lower operational costs per km ² than protected areas, yet half of those surveyed have less funding now than in 2019. Spatial analyses support field station presence as reducing deforestation. These “earth observatories” provide a high return on investment; we advocate for increased support of field station programs and for governments to support their vital conservation efforts by investing accordingly.

From first paragraph: The conservation of the world’s primates demands basic, but elusive and hard-to-get, information. Enormous efforts are underway to accumulate this information, and the fortuitous selection of six papers in this issue of Oryx illustrates these endeavours, each highlighting the sort of information needed. Besides a basic understanding of the diversity of primates, we need to know where they live (their geography and habitat requirements) and in what numbers. Only with such data is it possible to identify and evaluate the threats to their continued existence. Field research on particular aspects of primate ecology, behaviour, reproduction and demography provide an understanding of how primates respond to these threats and what conservation measures will be possible, effective and appropriate

There is evidence to suggest that the Coronavirus Disease 2019 (COVID-19) pandemic may hamper our achievement of the Sustainable Development Goals (SDGs). Here, we use non-human primates as a case study to examine the impacts of COVID-19 on the ability to achieve biodiversity conservation and management sustainability targets. We collected data through a survey of members of the IUCN SSC Primate Specialist Group from January to March 2022. Of the 93 experts that responded to our survey, we found that 39% had not been able to visit any of their field sites since March 2020, 54% said they had less funding available for their primate-related work, and only one out of ten said they had managed to achieve at least 76–100% of their planned primate-related work since March 2020. Six out of ten respondents (61%) felt that primate conservation efforts in protected areas were worse than before the onset of the COVID-19 pandemic and one-third (33%) felt hunting was happening more frequently than before. This study provides evidence of the impacts of COVID-19 on progress towards achieving the SDGs, and provides practical lessons learned for biodiversity conservation efforts moving forward.

Over the last half-century, the world’s human population has doubled, impacting almost all ocean and land areas. The threats facing primates in the wild have never been greater or more complex. Primatologists have long been aware of these threats and, since the 1970s, have coordinated efforts to safeguard these threatened species, through the International Union for Conservation of Nature Species Survival Commission (IUCN SSC) Primate Specialist Group (PSG). In an effort to stem the threat of extinction to primates, this group of now 700 experts+ has published 17 conservation action plans since 1977. As we look toward the next half-century, we take stock of the history of primate action planning to better understand the costs and benefits of these plans as a conservation tool. Here, we reviewed all plans published by the IUCN SSC PSG. In total, they described USD 246 million in planned primate conservation programming and were cited 1657 times by others. We found that half of the plans had been assessed in regard to their implementation, although these assessments were not standardized. Those that had been assessed, showed evidence of positive impacts on awareness raising, collaboration, fundraising, project implementation and policy, although the impact varied by plan. For example, three of the plans directly resulted in USD 15.92 million in funds raised; four plans quantified implementation rates, which ranged from 38% to 74% of actions partially or completely achieved 5 years after plan publication; and four plans attributed the gazettement of 19 protected areas across 11 countries as indirect successes following the publication of plans. Considered together, we reflect on the ‘return-on-investment’ for developing these plans and consider a range of ‘lessons learned’ for future primate action planning efforts.