Numerous island species have gone extinct and many extant, but threatened, island endemics require ongoing monitoring of their conservation status. The small tree Vachellia anegadensis was formerly thought to occur only on the limestone island of Anegada in the British Virgin Islands and was categorized as Critically Endangered. However, in 2008 it was discovered on the volcanic island of Fallen Jerusalem, c. 35 km from Anegada, and in 2018 it was recategorized as Endangered. To inform conservation interventions, we examined the species’ distribution, genetic population structure, dependency on pollinators and preferred habitat, and documented any threats. We found V. anegadensis to be locally widespread on Anegada but uncommon on Fallen Jerusalem and established that geographical location does not predict genetic differentiation amongst populations. Vachellia anegadensis produces the highest number of seed pods when visited by animal pollinators, in particular Lepidoptera. Introduced animals and disturbance by humans appear to be the main threats to V. anegadensis, and in situ conservation is critical for the species’ long-term survival.

Extinction is a profound biological event, yet despite its finality it can be difficult to verify and many frameworks have been proposed to define formally that extinction has occurred. For most taxonomic groups and regions there is no reliable list of species considered to be probably or possibly extinct. The record of plant extinctions in Australia is no exception, characterized by high turn-over within lists, low transparency of attribution and lack of consistency between jurisdictions. This makes it impossible to evaluate how many plant taxa have become extinct in Australia. We present an ecological framework for assessing the likelihood of plant extinctions, based on taxonomic soundness, degree of habitat modification, detectability and search effort, underpinned by the best available expert knowledge. We show that, in sharp contrast to both the fate of the Australian fauna and prevailing assumptions, only 12 of 71 plant taxa currently listed as or assumed to be extinct are considered probably extinct, and a further 21 possibly extinct. Twenty taxa listed as or assumed to be extinct have dubious taxonomy or occurrence in Australia, and the remaining 18 taxa are considered possibly extant and further surveys are required to ascertain their status. The list of probably and possibly extinct plants is dwarfed by the number thought extinct but rediscovered since 1980. Our method can be used for vascular floras in other regions characterized by well-documented and curated floras and high levels of expert knowledge, and provides a transparent platform for assessing changes in the status of biodiversity.

The recovery of species’ populations is one of the most challenging tasks in conservation, which is why species recovery is most likely to be successful if it involves as many stakeholders as possible. Podocarpus angustifolius, a tree endemic to Cuba, is potentially threatened by overexploitation, deforestation and expansion of exotic species. In December of 2017, in two protected areas containing the only known subpopulations of this species, we recorded the geographical position, height, and diameter at breast height of each individual, and calculated the extent of occurrence (EOO) and area of occupancy (AOO). We recorded a total of 575 individuals, 174 of which were adult (defined as ≥ 6 m height on the basis of the occurrence of reproductive structures), and most of which occurred in Lomas de Banao Ecological Reserve. The EOO and AOO were 125.8 km2 and 6.0 km2, respectively. All P. angustifolius that remain in the wild are within two protected areas, either in rainforest relicts or in coffee plantations. The size structure indicates a growing population. Based on our findings we recommend that P. angustifolius should be recategorized from Vulnerable (on the IUCN Red List) and Critically Endangered (on the national Red List) to Endangered, based on criterion D (small population size). We recommend the continued reinforcement of the population at Topes de Collantes Natural Protected Landscape and the continued engagement of local stakeholders for the long-term conservation of this species.

Forest ecosystems are rich in biodiversity and provide valuable ecosystem services, but are declining worldwide. Malus niedzwetzkyana, an Endangered wild relative of domesticated apples, is an important component of the walnut–fruit forests of Central Asia. Its iconic pink blossom and genetic properties give it special cultural and scientific significance, but livestock grazing and firewood collection threaten its survival. The conservation of the species and its native forest ecosystem is critical and urgent. This study provides information on the ecology and population of M. niedzwetzkyana and the threats affecting its habitat, improving our understanding of its distribution and proposing measures to reduce threats. We collected ecological data and assessed population structure and threats at four forest sites in southern Kyrgyzstan. We mapped 149 individuals, creating the largest known dataset for this species. We developed species distribution models for M. niedzwetzkyana to identify climatically suitable regions and potential areas for restoration. Sary-Chelek Biosphere Reserve contained the largest expanse of pristine forest and the most stable M. niedzwetzkyana population, followed by Kara-Alma Forestry Unit. Forests in the Gava Forestry Unit and Dashman Reserve were most extensively damaged by humans and livestock. The wild apple's favoured habitat was south-west facing slopes with a gradient < 30° and a relatively open canopy. Overall, the study population was vulnerable to extinction with limited regeneration potential. We recommend short-term population enhancement through planting projects and increased protection of individuals in pristine sites. Community-based conservation initiatives should be prioritized in extensively damaged sites, and larger-scale reforestation of these forests needs to be considered.

Traditionally the vulnerability of threatened species to extinction has been assessed by studying their environment, genetics and population dynamics. A more comprehensive understanding of the factors promoting or limiting the long-term persistence of threatened species could be achieved by conducting an analysis of their functional responses to changing environments, their ecological interactions, and their role in ecosystem functioning. These less traditional research areas can be unified in a trait-based approach, a recent methodological advance in ecology that is being used to link individual-level functions to species, community and ecosystem processes to provide mechanistic explanations of observed patterns, particularly in changing environments. We illustrate how trait-based information can be translated into well-defined conservation strategies, using the example of Dioon sonorense, an Endangered cycad endemic to north-western Mexico. Scientific information yielded by trait-based research, coupled with existing knowledge derived from well-established traditional approaches, could facilitate the development of more integrative conservation strategies to promote the long-term persistence of individual threatened species. A comprehensive database of functional traits of threatened species would be of value in assisting the implementation of the trait-based approach.

There is critical need for more information on the status of forests in Central Asia, to inform conservation management. Here we assess the status and use of the globally important, threatened walnut–fruit forests of Dashtijum Nature Reserve, Tajikistan. We use a mixed methods approach combining a semi-structured interview based socio-economic survey with statistical analysis. Thirty-three tree species were recorded, with Rosaceae the most common family. The mean basal area of the forest was 20.8 m2 per ha and most tree species exhibited stable population structures. Resource use was prevalent throughout the community; most households harvested at least one fruit or nut species (78%), firewood (88%) and grazed livestock (85%). Most respondents noted declines in availability of fruits, nuts and firewood and reported a decrease in the overall area and quality of grazing. Statistical analysis and machine learning identified that distance to nearest settlement significantly affected forest total basal area, tree species richness and the Shannon index, a metric of diversity sensitive to rare species. Our results suggest that conservation management by the government and NGOs is partly effective but there is a need for increased enforcement of grazing restrictions, to prevent further forest degradation.

Genetic data on threatened plant populations can facilitate the development of adequate conservation strategies to reduce extinction risk. Such data are particularly important for species affected by habitat fragmentation such as Magnolia cubensis subsp. acunae, a Critically Endangered magnolia subspecies endemic to Cuba. Using genetic data from 67 individuals, we aimed to evaluate the effect of habitat fragmentation on two subpopulations in the Guamuhaya mountain range, in Topes de Collantes Protected Natural Landscape and Lomas de Banao Ecological Reserve. We characterize the structure and genetic diversity of these subpopulations, with the objective of managing their conservation more effectively. We used Landsat satellite images to determine land-cover types at the two locations and calculated indices of habitat fragmentation. For genetic analyses, we extracted DNA from the leaf tissue of individuals from the two subpopulations and used 11 microsatellite markers to genotype them. We calculated heterozygosity, allelic richness and the F-statistics, to evaluate genetic variability. The montane rainforest in Topes de Collantes was most affected by habitat fragmentation, with smaller patches of more irregular shapes, compared to submontane forest at this location and both montane and submontane forests in Lomas de Banao. Genetic diversity was higher in Topes de Collantes, but we found no genetic differentiation between subpopulations. Our findings suggest the two subpopulations can be considered a single evolutionary unit and conservation entity. We propose to use individuals from both subpopulations for reinforcement to increase the overall genetic diversity of the subspecies.

Parakmeria omeiensis is a Critically Endangered tree species in the family Magnoliaceae, endemic to south-west China. The tree is functionally dioecious, but little is known about the species’ status in the wild. We investigated the range, population size, age structure, habitat characteristics and threats to P. omeiensis. We located a total of 74 individuals in two populations on the steep slopes of Mount Emei, Sichuan province, growing under the canopy of evergreen broadleaved forest in well-drained gravel soil. A male-biased sex ratio, lack of effective pollinating insects, and habitat destruction result in low seed set and poor seedling survival in the wild. We have adopted an integrated conservation approach, including strengthening in situ conservation, cultivation of saplings, ex situ conservation and reintroduction, to protect this species. The successful conservation of P. omeiensis has important implications for the conservation of the genus Parakmeria and the family Magnoliaceae.

Magnolia ovoidea is a narrowly endemic, Critically Endangered tree with a fragmented distribution in south-west Yunnan, China. We examined the size structure of this species, documented threats and assessed its extinction risk. We found the species in six locations, all in unprotected areas, in Maguan County. The largest subpopulations are in Donggua Lin and Youfang Po, with 17 and 50 living individuals, respectively. The distribution of the diameter at breast height of the M. ovoidea population has an inverse J-shape, indicating a stable size structure. However, the distribution of the height of seedlings is L-shaped, suggesting inhibited regeneration. The natural vegetation is severely fragmented in all six locations, surrounded by roads, farmlands, and Alnus nepalensis or Cunninghamia lanceolata plantations. We recommend that M. ovoidea should be categorized on the IUCN Red List as Critically Endangered based on criteria B2ab(iii) + C2a(i).

Cinnamomum chago is a woody species of the family Lauraceae endemic to Yunnan province, China, previously known from only one location, and categorized as a Plant Species with Extremely Small Population. We surveyed to determine the distribution and population size of C. chago, characterize its habitat, identify any threats, assess its conservation status, and provide guidelines for its management and conservation. During 2014–2017 we found only 64 mature C. chago, in five locations. These small, fragmented populations occur along Lancang River in Dali Prefecture at altitudes of 2,200–2,400 m. The species' extent of occurrence is c. 923 km2, with an area of occupancy of c. 60 km2. The habitat of the species has been degraded by expansion of pastoral activities and deforestation. We recommend categorization of C. chago as Endangered on the IUCN Red List, prevention of the collection of seeds and wood of the species, protection and monitoring, and ex situ propagation for future reintroductions.

Acer yangbiense Y.S. Chen & Q.E. Yang (Aceraceae) is a threatened tree species endemic to China, formerly presumed to have declined to only five extant individuals, restricted to Yangbi County, Yunnan Province. Our surveys in 2016, however, located 577 individuals in 12 localities, but only three localities (with a total of 62 individuals) are protected. Nine localities are on private forest land. The population's size structure is an inverse J-curve, but there is a scarcity of trees of the smallest size class and of seedlings. Our surveys also showed that the habitat of A. yangbiense is degraded as a result of the negative effects of agriculture, logging and wood harvesting. Assessment with the IUCN Red List categories and criteria indicates that A. yangbiense should be recategorized from Critically Endangered to Endangered.

In regions where primeval forests have vanished it is unclear whether forest protection can sustain specialized old-forest biota, and over what time scale. We report on population expansion of an old-growth specific fungus of European conservation concern, Amylocystis lapponica, in the forest reserve network of Estonia. This conspicuous species was known for 40 years from only single records in one old-growth forest and was categorized nationally as Critically Endangered. During the last 10 years A. lapponica has expanded over the eastern half of the country, with nine subpopulations, in 12 localities, now known, all in long-protected old-growth forests and several > 50 km apart. In most of the new localities historical absence of the species can be reliably assessed based on earlier surveys. The historical remnant subpopulation has also increased. The population size (c. 100 mature individuals) in Estonia indicates the species should be recategorized nationally as Endangered. This success story suggests that more than 50 years of non-intervention may be needed even in large old-forest reserves for old-growth specialist species to recover.

Vatica cauliflora P.S. Ashton (Dipterocarpaceae) is a threatened tree species endemic to Kapuas Hulu District, West Kalimantan Province, Indonesia. The species is only known from the type specimen collected in 1953. After this first collection, there was no record confirming the presence of this tree in its natural habitat. Our recent surveys in 2019 and 2020 located 179 individuals of the species in six unprotected locations. The population's size structure is dominated (62.6%) by young individuals within the 0–5 cm diameter class. Our surveys also showed that the habitat of V. cauliflora is degraded as a result of the negative effects of agriculture and logging. Assessment with the IUCN Red List criteria indicates that V. cauliflora should be categorized as Critically Endangered.