Cactaceae is one of the most threatened plant families, in part as a result of the illegal extraction of plants for ornamental use. However, reports of the seizure and reintroduction of cacti are scarce and do not include species of Melocactus, the genus of Cactaceae in Brazil that has the highest number of threatened species. The coroa-de-frade Melocactus violaceus is endemic to Brazil and categorized as Vulnerable on the IUCN Red List. We report the seizure of 37 individuals of coroa-de-frade extracted illegally from their natural habitat, the results of their reintroduction to Paulo César Vinha State Park, in Espírito Santo state, Brazil, and provide information for environmental monitoring agencies regarding how to proceed in seizure cases, with the goal of minimizing the impacts of this illegal practice on the species. After seizure, 25 individuals were cultivated in a greenhouse and 12 were reintroduced in restinga, the natural area of occurrence of the species. After 6 months, survival was 76% for those individuals cultivated in the greenhouse and 84% for those planted in restinga, showing that rapid reintroduction of species with ornamental appeal, preferentially in their natural habitat, can reduce the impacts of illegal extraction. This reintroduction protocol can be used by managers of conservation units, contributing to the maintenance of threatened cactus species in their natural habitat.

Large ground-dwelling Neotropical gamebirds are highly threatened by habitat loss and hunting, but conservationists rarely attempt to distinguish between these two threats in the management of populations. We used three different types of species records to determine the status (i.e. persistence level) of the Endangered red-billed curassow Crax blumenbachii in 14 forest remnants in north-east Brazil, as either persistent, precarious or extirpated. We related these persistence levels to variables measured in a 2-km buffer radius, including variables associated with habitat quality (proportion of forest cover, length of rivers, patch density, distance from rivers) and hunting pressure (proportion of cacao agroforests and farmlands, length of roads, total area occupied by settlements, distance from roads and from settlements). Curassows were more persistent in forest patches located (1) more distant from settlements, (2) in landscapes with few settlements, (3) in landscapes with a high incidence of roads, (4) in a mosaic with a high proportion of forest, shaded cacao agroforest and farmland, and (5) more distant from other forest patches. Hunting pressure potentially exerts more influence on persistence than habitat quality: (1) hunting pressure submodels had a higher explanatory power than habitat quality submodels, (2) final models comprised four hunting pressure variables but only two habitat quality variables, and (3) hunting pressure variables appeared in all models whereas habitat quality variables appeared in only one final model. If hunting pressure is driving declines in curassows, regions with low human presence and a high proportion of forest cover are recommended for establishing new reserves.

The Atlantic Forest is one of the most threatened tropical forests in the world. Many species have declined and become isolated because of pervasive forest loss and degradation. Here we assess the current population status of Atlantic Forest tree species from Santa Catarina state in southern Brazil to inform conservation policies and future management and protection. We used a novel methodology to generate automated conservation assessments from forest surveys and herbaria data, based on IUCN criteria A, B, C and D. We assessed more than 500 tree species whose populations are considered threatened. Population size reduction (i.e. IUCN criterion A) was the main indicator of threat, followed by restricted geographical range (criterion B). We observed population reductions of over 50% over three generations in more than 60% of the assessments. We recommend including taxonomically verified herbaria data to improve the accuracy of conservation assessments. The results obtained here can be used to identify important and potential regions for creating protected areas and implementing forest restoration programmes.

Despite significant efforts to assess conservation status, many endemic plants in Brazil remain largely unstudied, including Stachytarpheta, a genus of Verbenaceae with 90 species in the country, of which 82 are endemic. Working with the Brazilian National Center for Plant Conservation, we evaluated all endemic Stachytarpheta for the IUCN Red List. We concluded that 57% of endemic species are threatened (Critically Endangered, Endangered, Vulnerable), 6% are Near Threatened, 22% are Least Concern and 10% are Data Deficient. Threatened species are found exclusively in the Cerrado, Caatinga and Atlantic Forest biomes, where they face threats from livestock farming and ranching, agroindustry, mining and an increased frequency and intensity of wildfires. These species predominantly grow in campos rupestres and savannahs, especially in the Espinhaço Range in Bahia and Minas Gerais states and Chapada dos Veadeiros in Goiás state. At least 68% of the threatened species have one record within a protected area. We highlight the importance of Chapada Diamantina in Bahia and the Diamantina Plateau in Minas Gerais within the Espinhaço Range for the conservation of threatened and unprotected species. This study underscores the important role of taxonomists in the assessment of threatened species, emphasizes the need for further field surveys to gather key information about Data Deficient species and highlights the restricted distribution of several Stachytarpheta species in Brazil.

We report the rediscovery of two endemic tree species of the genus Myrcia (Myrtaceae) in the Brazilian Atlantic Forest in 2021–2022. Both Myrcia colpodes and Myrcia rubiginosa were previously known from a small number of specimens collected mostly in the 19th century in the Metropolitan Region of Rio de Janeiro state in Brazil. Living specimens had not been recorded since 1958 and 2005, respectively. We provide here photographic documentation and updated risk assessments for both species, which will be submitted to IUCN for a formal assessment. Our findings illustrate that rare species that have not been collected for long periods can sometimes be found in plain sight in urban forest fragments. We also highlight the importance of protected areas for the conservation of forest trees, in particular rediscovered species. We recommend a number of conservation actions and encourage the Brazilian government, scientific institutions and civil society to acknowledge the importance of these species and to act to safeguard their future.

Biological invasions can impact the dynamics of ecological processes. For primates of the genus Callithrix, congeneric introductions and hybridization are one of the greatest threats to native species. Three species of Callithrix have been recorded in Rio Doce State Park in south-east Brazil: the Endangered native buffy-tufted-ear marmoset Callithrix aurita and two introduced marmosets, the Geoffroy’s tufted-ear marmoset Callithrix geoffroyi and the black-pencilled marmoset Callithrix penicillata, but their relative abundance was unknown. We used the call playback method and adapted N-mixture models to estimate the abundance and of these marmosets in relation to canopy cover, tree circumference, tree density, number of lianas and epiphytes per tree, distances to nearest forest edge, road, tourist area and urban area, and detection probability in relation to survey effort, mean daily precipitation and temperature. We recorded 139 individuals (0.12 individuals/ha), all hybrids except for one C. aurita. Marmoset abundance was higher close to the forest edge, possibly as a result of the greater availability of food and shelter there. Detection probability was positively correlated with daily precipitation, most probably because marmosets foraged more actively when humidity was high. The situation in Rio Doce State Park is critical, with high hybridization levels and potential local extinction of C. aurita. We recommend that a management plan to conserve the remaining C. aurita is implemented urgently.

Begonia larorum is a threatened plant species endemic to Alcatrazes Island, south-east Brazil, which had not been recorded since its discovery in the 1920s. Here we report its rediscovery after more than a century since the first and only collection. In February 2024, we found a single individual in the forest understorey and successfully propagated it ex situ. Later that year we located a population of 19 individuals in an open area of vegetation prone to fires and invasive grasses and we obtained the first colour photographs of the species. Given its restricted range and the threats to its survival, we recommend the species be assessed for inclusion on the global IUCN Red List in addition to maintaining its Critically Endangered status at national level on the Red List of Brazilian Flora. We also propose in situ and ex situ conservation actions.

Reintroduction of locally extirpated species is an increasingly popular conservation tool. However, few initiatives focus on the restoration of ecological processes. In addition, many reintroductions fail to conduct post-release monitoring, hampering both assessment of their success and implementation of adaptive management actions. In 2009 a reintroduction effort was initiated to re-establish a population of the red-rumped agouti Dasyprocta leporina, a scatter-hoarding rodent known to be an important disperser of large seeds, with the aim of restoring ecological processes at Tijuca National Park, south-east Brazil. To assess whether this reintroduced population established successfully we monitored it using mark–resighting during November 2013–March 2015. Population size and survival were estimated using a robust design Poisson-log normal mixed-effects mark–resight model. By March 2015 the number of wild-born individuals fluctuated around 30 and overall growth of the population was positive. As the reintroduced population is capable of unassisted growth, we conclude that the reintroduction has been successful in the medium term. We recommend the cessation of releases, with efforts redirected to continued monitoring, investigation and management of possible threats to the species’ persistence, and to quantification of the re-establishment of ecological processes. Reintroduction of D. leporina populations can be a cost-effective tool to restore ecological processes, especially seed dispersal, in Neotropical forests.

The bush dog Speothos venaticus is a highly social Neotropical canid categorized globally on the IUCN Red List as Near Threatened, as Vulnerable in Brazil and as Critically Endangered in Minas Gerais, south-eastern Brazil, and the Atlantic Forest as a result of human pressure. As part of the monitoring of this mammal, during January 2019–March 2020 we placed one camera trap in each of 22 forest fragments in various landscapes in 15 municipalities in the state of Minas Gerais and one municipality in the state of Rio de Janeiro. On average, each camera trap was active for 4.3 months in each fragment. In a total of 2,856 trap-days we obtained the first record of S. venaticus in south-eastern Minas Gerais, c. 2 km from Serra de Santa Rita Mítzi Brandão Biological Reserve. This is the northernmost record of S. venaticus in the Atlantic Forest and highlights the importance of forest remnants in a fragmented landscape for this species. Further monitoring of this area should be a priority, to increase knowledge regarding the distribution of this species and for developing conservation strategies appropriate to these fragmented landscapes.

Ensuring the demographic and genetic viability of small populations of threatened primates requires a range of management approaches. Here we describe a novel mixed in situ and ex situ management project that was developed to restore a population of the Critically Endangered northern muriqui Brachyteles hypoxanthus. This isolated population, located in Ibitipoca, Lima Duarte, Minas Gerais, Brazil, had declined to two adult males and would have gone extinct without intervention. A first attempt at in situ management in 2017 involved the translocation of a solitary female from another region, but this female did not associate or interact with the males and disappeared after 9 months. We thus initiated a second and ongoing ex situ management project that involved constructing a complex consisting of a large, open-air enclosure abutting a small patch of forest surrounded by an open area in the process of restoration, all of which is protected by electric fencing. The entire area within the fencing is called Muriqui House. The two Ibitipoca males and two solitary, wild females from another location were captured and released into the enclosed part of Muriqui House between March 2019 and January 2020 and into the forested part of Muriqui House in February 2020. The birth of an infant in this group in November 2020 and the acceptance by the group of a third female translocated from another area in January 2021 demonstrate the potential of this approach for the recovery of this isolated population, with positive implications for the conservation of the species.

Grazielanthus is a monotypic, dioecious and microendemic plant genus of the Brazilian Atlantic Forest. Its only species, Grazielanthus arkeocarpus, is categorized as Critically Endangered on the IUCN Red List and comprises only one small population, in the Poço das Antas Biological Reserve, Rio de Janeiro State. Collaborative activities have been developed since 2013 to implement in situ and ex situ conservation actions for this species. Successful in situ planting has increased the number of individuals in its natural population. Ex situ conservation efforts have resulted in the cultivation of the species in two Brazilian living plant collections, and this will soon increase to three collections.

The Atlantic Forest of South America supports a rich terrestrial biodiversity but has been reduced to only a small extent of its original forest cover. It hosts a large number of endemic mammalian species but our knowledge of arboreal mammal ecology and conservation has been limited because of the challenges of observing arboreal species from ground level. Camera trapping has proven to be an effective tool in terrestrial mammal monitoring but the technique has rarely been used for arboreal species. For the first time in the Atlantic Forest, we obtained data on the arboreal mammal community using arboreal camera trapping, focusing on Caparaó National Park, Brazil. We placed 24 infrared camera traps in the forest canopy in seven areas within the Park, operating them continuously during January 2017–June 2019. During this period the camera traps accumulated 4,736 camera-days of footage and generated a total of 2,256 photographs and 30-s videos of vertebrates. The arboreal camera traps were able to detect arboreal mammals of a range of body sizes. The mammal assemblage comprised 15 identifiable species, including the Critically Endangered northern muriqui Brachyteles hypoxanthus and buffy-headed marmoset Callithrix flaviceps as well as other rare, nocturnal and inconspicuous species. We confirmed for the first time the occurrence of the thin-spined porcupine Chaetomys subspinosus in the Park. Species richness varied across survey areas and forest types. Our findings demonstrate the potential of arboreal camera trapping to inform conservation strategies.

Tropical forest hotspots have a high diversity of species but have lost > 70% of their original vegetation cover and are characterized by a multitude of small and isolated fragments. Paradoxically, conservation actions in these areas are still mainly focused on protection of large tracts of forests, a strategy now infeasible because of the small area of forest remnants. Here we use the Vulnerable black-handed titi monkey Callicebus melanochir as a model to study the effects of habitat loss, fragmentation and degradation on arboreal mammals and to provide insights for science-driven conservation in fragmented landscapes in tropical forest hotspots. We surveyed 38 Atlantic Forest fragments in Bahia State, Brazil and assessed the effects of patch area, quality and visibility, and landscape connectivity on the occurrence of our model species. Patch area was the single best model explaining species occurrence. Nonetheless, patch quality and visibility, and landscape connectivity, positively affect occurrence. In addition to patch area, patch quality, patch visibility and landscape connectivity are useful for predicting the occurrence of arboreal mammals in the fragments of tropical forest hotspots. We encourage the assessment of habitat quality (based on remotely sensed vegetation indices) and habitat visibility (based on digital elevation models) to improve discoverability of arboreal mammal populations and selection of fragments for conservation purposes across fragmented landscapes of tropical forest hotspots. Large remnants of tropical forest hotspots are scarce and therefore we require baseline data to support conservation actions and management in small forest fragments.

Begonia jocelinoi Brade (Begoniaceae) is a threatened species, endemic to a small locality in the Brazilian Atlantic Forest. The species was formerly listed as Wanted in the Red List of Endemic Flora of the state of Rio de Janeiro because it had not been recorded since 1953. After evaluating herbarium collections and conducting fieldwork during May 2019–February 2020, we report the rediscovery of a single population of 65 reproductive individuals of B. jocelinoi, along with numerous seedlings, besides a trail in Itatiaia National Park. This Park is an IUCN category II protected area that permits some tourism activities. Some individuals of B. jocelinoi showed signs of pruning following the maintenance of the trail. We recommend strategies for in situ and ex situ conservation of this narrowly endemic species, including provision of advice to tourists regarding the occurrence of threatened species, and diversion of the trail where the species occurs.