Multiple drivers influence tree species diversity and above-ground carbon stock in second-growth Atlantic forests: Implications for passive restoration.

Second-growth forests (SGF) are critical components for limiting biodiversity loss and climate change mitigation. However, these forests were established after anthropic disturbances such as land use for planting, and in highly human-modified landscapes. These interventions can decrease the ability of biological communities to recover naturally, and it is necessary to understand how multiple drivers, from local scale to landscape scale influence the diversity and carbon stock of these forests in natural regeneration. For this, we used data from 37 SGF growing on areas previously used for eucalyptus plantations in the Brazilian Atlantic Forest, after the last cut cycle. For each SGF, the forest tree species diversity was calculated based on the Hills number, and we also calculated the above-ground carbon stock. Then, we evaluated the influence of multiple environmental factors on these indexes: soil properties, past-management intensity, patch configuration, and landscape composition. Little influence of soil properties was found, only soil fertility negatively influenced above-ground carbon stock. However, past-management intensity negatively influenced tree species diversity and carbon stock. The isolation of other forests and tree species propagules source distance (>500 ha) also negatively influenced the diversity of species. This is probably due to the favoring of tree pioneer species in highly human-modified landscapes because they are more tolerant of environmental changes, less dependent on animal dispersal, and have low carbon stock capacity. Thus, areas with higher past-management intensity and more isolated areas are less effective for passive restoration and may require intervention to recover tree diversity and carbon stock in the Atlantic Forest. The approach, which had not yet been applied in the Atlantic Forest, brought similar results to that found in other forests, and serves as a theoretical basis for choosing priority areas for passive restoration in the biome.

Projected Status of the Ghost Orchid (Dendrophylax lindenii) in Florida during the Next Decade Based on Temporal Dynamic Studies Spanning Six Years.

The enigmatic ghost orchid, Dendrophylax lindenii (Lindley) Bentham ex Rolfe, is a showy leafless epiphyte restricted to low-lying forests in south Florida and western Cuba. Because of its appeal and reputation for being difficult to cultivate, D. lindenii remains vulnerable to poaching and environmental changes. About 2000 individuals are assumed to remain in Florida, most confined within water-filled cypress domes in the Fakahatchee Strand, but virtually no information exists on current population numbers throughout the region. This paper provides a preliminary summary of the ghost orchid's projected status based on six continuous years of data collected within the Florida Panther National Wildlife Refuge (FPNWR) from 2015-2020. The orchids were clustered in seven different populations, each separated by ca. 5 km. Quantitative data were collected spanning three age classes (seedlings, juveniles, mature plants) for each population, and survival, flowering, and fruiting were noted. To estimate the temporal variability in the demographic rates, size-structured integral projection models (IPMs) were constructed for each annual transition (e.g., 2015-2016, 2016-2017). Results for all seven populations pooled suggest that D. lindenii numbers will decline by 20% during the next decade in the absence of external adverse factors. Seedling recruitment is not expected to keep pace with the projected decline. Only one population, which was also from the wettest location, continuously harbored spontaneous seedlings, suggesting that most populations within the FPNWR lack conditions suitable for reproduction.

Integrating Gut Bacterial Diversity and Captive Husbandry to Optimize Vulture Conservation.

Endangered species recovery plans often include captive breeding and reintroduction, but success remains rare. Critical for effective recovery is an assessment of captivity-induced changes in adaptive traits of reintroduction candidates. The gut microbiota is one such trait and is particularly important for scavengers exposed to carcass microbiomes. We investigated husbandry-associated differences in the gut microbiota of two Old World vulture species using 16S RNA gene amplicon sequencing. Increased abundance of Actinobacteria occurred when vultures were fed quail but not rat or chicken. Conversely, diet preparation (sanitization) had no effect, although bacterial diversity differed significantly between vulture species, likely reflective of evolved feeding ecologies. Whilst the relative lack of influence of a sanitized diet is encouraging, changes in bacterial abundance associated with the type of prey occurred, representing a dietary influence on host-microbiome condition warranting consideration in ex situ species recovery plans. Incorporation of microbiome research in endangered species management, therefore, provides an opportunity to refine conservation practice.

How much does it cost to save a species from extinction? Costs and rewards of conserving the Lear's macaw.

Although the limited resources available to save species from extinction necessitate the optimization of conservation actions, little is known about their costs and effectiveness. We developed a costs-rewards framework that integrates information on which sectors of society contribute to funding conservation, how much is contributed, how funds are distributed among conservation targets and how these investments drive not only conservation rewards but also the economic and ecosystem services that benefit society. We applied this framework to the Lear's macaw (Anodorhynchus leari), a species discovered in the wild in 1978 with only 60 individuals. Funds invested over the last 25 years reached US$3.66 million. The contribution of governments, non-governmental organizations and private funders varied over time, as did the funding targets. Funds were proportionally invested to mitigate the main causes of mortality, while no funds were devoted to protecting foraging habitats. Conservation rewards were satisfactory, with the cost and time needed to downlist the species from critically endangered to endangered being similar to those invested in other bird species. However, economic rewards (through ecotourism and handicrafts linked to the conservation of the species) were low and require promotion, while ecosystem services provided by Lear's macaws have yet to be quantified.

Effect of Canine Parvovirus and Canine Distemper Virus on the Mexican Wolf (Canis lupus baileyi) Population in the USA.

Mexican wolves (Canis lupus baileyi), classified as probably extinct in the wild in Mexico and endangered in the US, were reintroduced into Arizona in 1998. We combined annual serologic testing results from samples collected between 2003 and 2016 from 108 wolves and known survival data from 118 wolves born in the recovery area from 2003 to 2014 to evaluate whether exposure to canine distemper virus (CDV) or canine parvovirus (CPV) was associated with a greater risk of mortality before 2 yr of age. We used mixed-effects logistic regression to estimate the effect of CDV and CPV on the probability of mortality. Annual seroprevalence rates for CDV and CPV ranged from 0% to 62% and from 33% to 100%, respectively (median, 14.2% and 90.3%, respectively). The covariate, age at testing, had a negative effect on mortality, indicating that younger animals had lower survival, whereas sex had little effect on mortality. The best-supported model excluded any effect of CPV or CDV on death before 2 yr old at both the pack and individual level. Although our analysis did not detect an effect of these viruses on mortality before 2 yr old, CDV was later identified as the cause of mortality in two individuals in 2017. Additional information is needed to assess the impact of these diseases on Mexican wolves.