An estimate of the area of occupancy and population size of Brachycephalus tridactylus (Anura: Brachycephalidae) to reassess its conservation status, with a proposal for conservation measures

Background We are experiencing a global crisis in conservation, which has led to the prioritization of targets, such as nations, regions, and animal groups, which are necessary while resources are disputed. Brazil is a priority not only because of its megadiversity, high rates of endemism, and frequent descriptions of new species but also because of its high levels of deforestation. Among the species groups prioritized for conservation is the anurans (Amphibia: Anura), the population of which is severely declining. One group of anurans is the genus Brachycephalus, which includes 37 endemic species in the Brazilian Atlantic Rainforest. Some of these species have highly restricted distributions (<100 ha). Thirty new species have been described since 2000, and 55.3% of all species are threatened with extinction. Brachycephalus tridactylus was only recently described and remains restricted to its type locality. Because of its reduced geographical distribution (0.41 km2), it has been proposed to be considered as Vulnerable. The objective of this study is to reevaluate the conservation status of Brachycephalus tridactylus and propose conservation measures. Methods We searched for new populations during 2016–2020, evaluated in loco impacts and potential impacts on the species’ population, and performed an analysis of the density of this population and estimated its size. International Union for Conservation of Nature (IUCN) criteria were used to assess the conservation status of the species. Results We recorded the species in seven new localities (from 715–1,140 m above sea level) in the state of São Paulo up to 33 km from the type locality of the species (in state of Paraná). We estimated the area of occupancy as 148.44 km2, densities as one calling male per 4.05 m2 and 130.00 m2, and a total population size of 4,429,722 adult individuals. Based on our finding, we proposed three lines of management: (1) formation of fire brigades, (2) management of residents’ mules in the conservation unit and surrounding areas, and (3) management of degraded areas. We recommend changing the species’ conservation status from Vulnerable to Endangered because of its fragmented distribution and decline in the area of occupancy and in the quality of its habitat. Our results have expanded the species previous geographic distribution and delimited areas without previous records. Our estimates of population density and size are in accordance with those verified for congeners. The conservation of this species benefits the environments and other species that inhabit them, being, therefore, strategic for receiving conservation actions that will spread throughout the ecosystem.

Estimating Actual Abundance of European Sousliks: Using UAV Imagery, Pixel Based Image Analysis and Random Forest Classification to Count Souslik Burrows

Burrowing mammals are widespread and contribute significantly to soil ecosystem services. However, how to conduct a non-invasive estimation of their actual population size has remained a challenge. Results support that the number of burrow entrances is positively correlated with population abundance and burrows’ location indicates their area of occupancy consequently it provides a benchmark for estimating population size. European souslik is an endangered burrowing species in decline across its range. We present an imagery-based method to identify and count animals’ burrows semi-automatically by combining remotely recorded RGB images, pixel-based imagery (PBI) and Random Forest (RF) classification. Field images recorded in four colonies were collected, combined and then processed by histogram matching and spectral band normalisation to improve the spectral distinction between the categories BURROW, SOIL, TREE, GRASS. Raw or processed images were analysed by RF classification to compare the change in accuracy metrics as a result of processing. From accuracy metrics kappa of precision (κBURROWP) and sensitivity (κBURROWS) for BURROW were 95 and 90% respectively. A 10-time bootstrapping of the final model resulted in coefficients of variation (CV%) of κBURROWS and κBURROWP lower than 5%, moreover CV% values were not significantly different between precision and sensitivity scores. The consistency of classification results and balanced precision and sensitivity confirmed the applicability of this approach. Our method provides an accurate and user-friendly tool to count the number of burrow openings and delineate the areas of occupancy as compared to traditional, more invasive approaches or other computer capacity and end-user expertise demanding methods.

Updated range metrics and a global population estimate for the Critically Endangered Philippine Eagle using a spatial ensemble habitat model

Many range-restricted taxa are currently experiencing severe population declines yet lack fundamental biological information regarding distribution and population size. Establishing baseline estimates for both these key biological parameters is however critical for directing long-term monitoring and conservation planning for at-risk range-restricted species. The International Union for the Conservation of Nature (IUCN) Red List uses three spatial range metrics that define species distributions and inform extinction risk assessments: extent of occurrence (EOO), area of occupancy (AOO) and area of habitat (AOH). However, calculating all three metrics using standard IUCN approaches relies on a geographically representative sample of locations, which for rare species is often spatially biased. Here, we apply model-based interpolation using an ensemble Species Distribution Model (SDM), correlating occurrences with remote-sensing derived environmental covariates, to calculate IUCN range metrics and a global population estimate for the Critically Endangered Philippine Eagle (Pithecophaga jefferyi). Our ensemble averaged SDM had high predictive accuracy and was able to identify key areas of Philippine Eagle habitat across the species global range. We estimated an AOH = 49,426 km2 and from this metric calculated a maximum EOO = 609,697 km2 and a minimum EOO = 273,794 km2, with an AOO = 54,695 occupied cells. Based on inferred habitat from the AOH metric and territorial habitat area from home range estimates, we provide an updated global population estimate of 677 breeding pairs (range: 549-772 pairs), or 1354 mature individuals, across the entire Philippine Eagle range. We demonstrate that even when occurrence sampling is geographically biased, robust habitat models can be built which enable quantification of IUCN range metrics and a baseline population size estimate. In the absence of adequate location data for many rare and threatened taxa, our method is a promising spatial modelling tool with widespread applications, in particular for island endemics facing high extinction risk.

Comparison of Catasetum bicolor and C. ochraceum (Catasetinae: Orchidaceae) habitat preferences: implications for their conservation

Family Orchidaceae is widely recognized for its mutualistic relationship with their pollinators, however, the knowledge about the most diverse monocotyledonous group on the planet it is still limited. Here, we recognized the ecological requirements and modeled the habitat preferences for Catasetum bicolor and C. ochraceum (Subfamily: Epidendroideae). We used climatic and bioclimatic data along with species’ occurrences records in a) Principal Components Analysis (PCA) to screen for the most influential variables; and, b) a maximum entropy algorithm (Maxent) for habitat suitability modeling. Also, preliminary conservation status and probable priority areas for monitoring and conservation were identified. Both species differed in their habitat preferences as shown by the altitudinal range. Factors screened by PCA were associated to temperature (average, minimum, seasonality), solar radiation, and precipitation of the driest and warmest months. The variables that influenced the most in the modeling process for C. bicolor were solar radiation, temperature seasonality, and its annual range; while for C. ochraceum were the precipitation of the driest month and solar radiation. Areas with habitat suitable conditions were identified in countries (Brazil, Colombia, Costa Rica, Ecuador, Nicaragua, Panama, and Venezuela) and biomes (humid and dry tropical, and subtropical forests) with highly dynamic land cover changes. The studied species were found to be in an endangered status based on their area of occupancy (< 76 km2). However, considering their extent of occurrence (> 20000 km2), they are in a status of less concern. These findings may be relevant for future monitoring plans and planning for ex-situ and in-situ conservation strategies.

Conservation status revision and communities’ perceptions of 22 Aloe species in Tanzania

Background and aims – Many Aloe species are globally threatened due to overharvesting for trade and habitat destruction. CITES regulates their international trade. In Tanzania, 50% of all existing Aloe species had previously been assessed, though some of these assessments were Data Deficient. For those with sufficient data, an update is required as the rate of decline has rapidly increased over the last years. Material and methods – We estimated Area of Occupancy (AOO), Extent of Occurrence (EOO), and number of locations for 22 Tanzanian Aloe species using the Geospatial Conservation Assessment software (GeoCAT). We assessed the reasons leading to their decline based on direct field observations and community perceptions. Key results – We revised the conservation status of 22 Aloe species; two were assessed as Critically Endangered, ten as Endangered, five as Vulnerable, and five as Least Concern. We re-discovered the Critically Endangered Aloe boscawenii, which had not been seen in Tanzania for more than six decades. We propose to downgrade the endemic Aloe dorotheae, Aloe leptosiphon, and Aloe flexilifolia from Critically Endangered to a lower threat level. The community perception on Aloe species availability did not accurately reflect their categorisation based on the IUCN criteria B. We identified agricultural activities and climate change effects as the two main threats to Tanzanian Aloe species.Conclusion – We conclude that overall numbers are declining for 22 Aloe species in Tanzania, mainly due to human activities. We recommend the implementation of laws and policies to protect their natural habitats.

Echeandia cholulensis (Asparagaceae), a new species from central Mexico

Background and Aims: The genus Echeandia (Asparagaceae) characterizes the Mexican geophyte flora. The group is exclusive of the Americas and includes 85 species. In Mexico, there are 74 species, of which 63 are endemic; however, the species richness is concentrated in the Mexican Transition Zone, including the Transmexican Volcanic Belt (TMVB). Here, we name and describe a new species of Echeandia found along the TMVB in the states of Puebla and Tlaxcala.Methods: Field work and herbarium revision led us to discover a new species of Echeandia. The morphological description and illustration were based on eight voucher specimens plus living plants from two populations. Moreover, we compared the morphology of the new taxon with that of E. michoacensis and E. robusta. Lastly, we assessed its conservation status by calculating its extent of occurrence (EOO) and its area of occupancy (AOO), using the GeoCAT tool and based on the IUCN Red List categories and criteria.Key results: Echeandia cholulensis is a new species from Mexico. The new taxon includes robust plants characterized by root-thickenings distant from the corm; lanceolate, undulate, and glaucous leaves; ascending flowers with white tepals; clavate and muricate filaments, and free anthers with longitudinal dehiscence. Until now, it is known from three populations in central Mexico in the states of Puebla and Tlaxcala.Conclusions: Along the TMVB, volcanism has created topographic and climatic variation favoring speciation and persistence. The discovery and morphological description of Echeandia cholulensis exemplifies this observation. Furthermore, botanical exploration and herbaria revisions might discover new species that would increase the great plant diversity of the TMVB.

Assessing Pathways of Climate Change Effects in SpaDES: An Application to Boreal Landbirds of Northwest Territories Canada

Distributions of landbirds in Canadian northern forests are expected to be affected by climate change, but it remains unclear which pathways are responsible for projected climate effects. Determining whether climate change acts indirectly through changing fire regimes and/or vegetation dynamics, or directly through changes in climatic suitability may allow land managers to address negative trajectories via forest management. We used SpaDES, a novel toolkit built in R that facilitates the implementation of simulation models from different areas of knowledge to develop a simulation experiment for a study area comprising 50 million ha in the Northwest Territories, Canada. Our factorial experiment was designed to contrast climate effects pathways on 64 landbird species using climate-sensitive and non-climate sensitive models for tree growth and mortality, wildfire, and landbirds. Climate-change effects were predicted to increase suitable habitat for 73% of species, resulting in average net gain of 7.49 million ha across species. We observed higher species turnover in the northeastern, south-central (species loss), and western regions (species gain). Importantly, we found that most of the predicted differences in net area of occupancy across models were attributed to direct climate effects rather than simulated vegetation change, despite a similar relative importance of vegetation and climate variables in landbird models. Even with close to a doubling of annual area burned by 2100, and a 600 kg/ha increase in aboveground tree biomass predicted in this region, differences in landbird net occupancy across models attributed to climate-driven forest growth were very small, likely resulting from differences in the pace of vegetation and climate changes, or vegetation lags. The effect of vegetation lags (i.e., differences from climatic equilibrium) varied across species, resulting in a wide range of changes in landbird distribution, and consequently predicted occupancy, due to climate effects. These findings suggest that hybrid approaches using statistical models and landscape simulation tools could improve wildlife forecasts when future uncoupling of vegetation and climate is anticipated. This study lays some of the methodological groundwork for ecological adaptive management using the new platform SpaDES, which allows for iterative forecasting, mixing of modeling paradigms, and tightening connections between data, parameterization, and simulation.

Future Representation of Species’ Climatic Niches in Protected Areas: A Case Study With Austrian Endemics

Climate driven species’ range shifts may interfere with existing protected area (PA) networks, resulting in a mismatch between places where species are currently protected and places where they can thrive in the future. Here, we assess the climate-smartness of the Austrian PA network by focusing on endemic species’ climatic niches and their future representation within PAs. We calculated endemic species’ climatic niches and climate space available in PAs within their dispersal reach under current and future climates, with the latter represented by three climate change scenarios and three time-steps (2030, 2050, and 2080). Niches were derived from the area of occupancy of species and the extent of PAs, respectively, and calculated as bivariate density kernels on gradients of mean annual temperature and annual precipitation. We then computed climatic representation of species’ niches in PAs as the proportion of the species’ kernel covered by the PA kernel. We found that under both a medium (RCP 4.5) and severe (RCP 8.5) climate change scenario, representation of endemic species’ climatic niches by PAs will decrease to a sixth for animals and to a third for plants, on average, toward the end of the century. Twenty to thirty percent of Austrian endemic species will then have no representation of their climatic niches in PAs anymore. Species with larger geographical and wider elevational ranges will lose less climatic niche representation. The declining representation of climatic niches in PAs implies that, even if PAs may secure the persistence of a part of these endemics, only a small portion of intraspecific diversity of many species may be represented in PAs in the future. We discuss our findings in the context of the varied elevational gradients found in Austria and suggest that the most promising strategies for safeguarding endemic species’ evolutionary potential are to limit the magnitude of climate change and to reduce other pressures that additionally threaten their survival.

On the Origin of Feces: Fungal diversity, distribution, and conservation implications from feces of small mammals

Fungi are extremely diverse, but only a small fraction of the total estimated species have been characterized. Often, the extent of diversity and distribution of fungal communities is difficult or near impossible to assess. This is due to the fact that many Fungi are cryptic and persist predominantly hidden within substrates such as soil or plant material. This is particularly true for hypogeous sporocarps, including truffles, which are extremely difficult to survey in a systematic manner. However, fungi with hypogeous sporocarps have evolved traits that make them highly attractive to animals, such as small mammals, which ingest and disperse fungal spores through defecation. Here, samples of feces from 138 small mammals collected in the western United States were assessed for total fungal diversity using a dual-index metabarcoding, high-throughput Illumina sequencing approach. Our findings exhibit many identifications within Agaricomycetidae, with 65 of the 138 samples containing sequences belonging to several species of the hypogeous truffle genus Rhizopogon. Metadata, such as geospatial coordinates, for each captured small mammal can be used as a proxy for the presence or absence of Rhizopogon species identified in their feces. Utilizing these proxy data, along with publicly available data on observation and occurrence from data repositories such as GBIF and MycoPortal, it is possible to augment our current knowledge of the extent of occurrence and area of occupancy of cryptic hypogeous fungi without direct observation, further enhancing our ability to assess their conservation status.

Conservation Status of Agarwood-Producing Species (Gyrinops versteegii) in Indonesia

Aquilaria malaccensis and Gyrinops versteegii are agarwood producing plant species that is widely used because of its fragrance. Gyrinops versteegii has not been much cultivated and along with the decreasing population of G. versteegii in its natural habitat. This study aimed to assess scarcity status of Gyrinops versteegii based on distribution records from both herbarium and field exploration to assist the formulation of its conservation policy. Distribution data were obtained from online database and also from field exploration in Lombok, Sumbawa, and Flores Islands to obtain the population information. Area of Occupancy (AOO) and Extent of Occurrence (EOO) were calculated using GeoCAT (Geospatial Conservation Assessment Tool) and IUCN status recommendation was discussed. The estimated EOO was 868,422,919 km2, exceeding the value required for the threatened category. Based on EOO, it is included in the Least Concern (LC) category, but the EOO covers a large area of the ocean so the AOO was 116 km2 as meets criterion B (AOO<500 km2). It can be categorized into endangered (EN). Population data and conservation status of G verstegii are very important to provide recommendations on the quota wild-harvesting of agarwood by stakeholders.