Species distribution modeling has become increasingly important as climate change drives significant habitat shifts in plant and animal species, particularly those that provide essential ecosystem goods and services. One such species is the African rosewood tree (Pterocarpus erinaceus), which faces severe threats in sub-Saharan Africa due to habitat loss and anthropogenic pressures, while its distribution patterns and ecological requirements remain incompletely understood. Naturally occurring in various savanna ecosystems, the species has suffered considerable population declines over recent decades. This study employs ensemble modeling to predict both current and future distribution potential for P. erinaceus in Burkina Faso, incorporating 54 environmental variables to assess habitat suitability under projected climate scenarios for 2050 and 2070. Using greenhouse gas concentration trajectories RCP4.5 and 8.5, along with general circulation models CNRM-CM5 and HadGEM2-CC, researchers evaluated the species’ vulnerability to climate change. Additionally, a network of protected areas in Burkina Faso was analyzed to determine their role in conservation efforts. Key environmental factors influencing P. erinaceus distribution include isothermality (31%), minimum temperature of the coldest month (31%), soil pH at a depth of 0–5 cm (11%), silt content at 60–100 cm (9.2%), and precipitation during the warmest quarter (8%). Under current climate conditions, highly suitable habitats span approximately 129,695 km², covering 47% of Burkina Faso. However, projections indicate a significant decline in suitable habitat, with potential losses of up to 61% under future climate scenarios. Given these findings, urgent conservation measures are necessary to safeguard P. erinaceus within its native range. This study provides valuable insights for land managers, helping them prioritize conservation areas and avoid introducing the species into unsuitable environments unless appropriate management strategies are implemented.
Tag: endangered species
Mapping the biodiversity of “cinderella” trees in Cameroon
The domestication of indigenous tropical trees starts with the identification of germplasm collection sites. Collecting from a wide genetic base enhances the ecological quality of each collection activity. Determining species occurrence, potential collection sites, and distribution by relying too heavily on published information based on their ‘biophysical limits’ has shown itself to be full of practical challenges. Within the tree domestication process, the identification and illustration of the geographic re-distribution of high-value tropical trees through their cultivation by farmers, enriches the process of tree germplasm collection. This paper draws parallels between tree cultivation by farmers in Cameroon and the inadvertent testing of the trees in niches and habitats often different from the natural homes of the species. By forcing species to adapt in regions other than those in which they might have been naturally selected, farmers ‘force’ certain genetic attributes of individual trees, necessary for their survival, to be expressed in one form of adaptation or another. The surviving trees may subsequently constitute unique stands with peculiar genetic and/or phenotypic characteristics. As these resilient man-made stands spread across broad geographical areas, mapping them becomes equivalent to recording an expression of that ‘resilience’ factor in the species. Recording these sites with the rest of its natural range of occurrence is thus equal to mapping the species’ diversity or its ‘domestication range’. The methodology used in this study utilized published biophysical information on vegetation, precipitation, temperature and altitude, as well as geographic data on germplasm collection, cultivation sites and natural stands. These data layers were then used to suggest zones of possible occurrence and distribution. Field collections and survey activities were later used to verify incidence and cultivation sites of four sample tropical tree species, in Cameroon: Irvingia gabonensis, Cola nitida, Prunus africana, and Dacryodes edulis.
Prunus africana: how agroforestry can help save an endangered medicinal tree
I studied the uses of the African cherry (Prunus africana) by four ethnic groups who live near the Kilum-Ijim Forest Preserve on Mount Oku, Cameroon. Prunus africana is valued for its timber, which is used for tool handles and for fuel, and it is an important wildlife food. However, its greatest value is for traditional medicines. Healers use the bark and leaves to treat more than 30 human ailments and several animal diseases and it is the most important plant used in their practices. This study is the first to document this importance, particularly for animal medicines. I also examined the growing worldwide herbal use to treat benign prostatic hyperplasia. Market demand has caused resource depletion and an erosion of traditional resource protection practices. Preservation of the species will depend on sustainable harvesting methods and on cultivation.
Collecting germplasm from trees-some guidelines’
There are many reasons for collecting tree germplasm.There may bea need for planting material that will be distributedimmediately to users-farmers or horticul- :turists or extensionworkers. With the rapid rate of deforesta- tion throughout thetropics, many species of trees-and their: genetic wealth-areendangered and the collection may be.to conserve their germplasm for posterity. In addition, : germplasm may be collected because it is needed for tree-.improvement programmes. Germplasm collection is a key step in anyprocess to do-.mesticate trees;the genetic variation of a speciesshould be : present in the collected germplasm, and this is needed for. the selection and improvement that are part ofdomestica-:tion. Many tropical trees have undergone little or nodomes-.tication,so the best source of germplasm for improvement:of these species is wild populations.However,collecting is . also often done in exotic stands, because theyare relatively :easy to get at and they provide a good comparative base in.trials to assess the performance ofdifferent sources of . germ plasm
Bornean orangutan Pongo pygmaeus pygmaeus population estimate within and around Danau Sentarum National Park, Kapuas Hulu, West Kalimantan
Of the three subspecies of Critically Endangered Bornean orangutans, Pongo pygmaeus pygmaeus has the smallest population size. One of its most important habitats is the tropical forest within and around Danau Sentarum National Park (DSNP). Research in the late 1990s estimated that ca. 1025 orangutans inhabited DSNP, while ca. 1717 orangutans inhabited the forest beyond DSNP’s boundaries. However, concerns were later raised that incorrectly estimated nest decay rates (t values) may have led to the overestimation of the population size. Furthermore, the area experienced forest degradation and land use change between 2000 and 2013. Given these changing landscapes, updated population estimates were needed to inform policy makers and land-use planners on the implications of habitat loss for resident orangutans. We conducted this study to recalculate nest decay rates based on current recommended methods, and to update our knowledge on the orangutan population in the region. Our average nest decay rate was 288.3 days; applying this to the study in the late 1990s generated estimates of 807 individuals within DSNP and 1578 beyond DNSP’s boundaries. New surveys of the transects undertaken between 2010 and 2014 revealed that the population size had declined substantially in these two areas, to 202 and 71 individuals respectively. Both declines are considerable, but larger losses occurred in logged-over and cleared forests outside the park. We discuss factors potentially driving these declines, emphasizing the need to improve habitat protection both inside and outside of DSNP, and make recommendations for improving the prospects for future orangutan conservation.
Terrestrial vertebrate and butterfly diversity of Garbhanga Landscape, Assam, India
A study was conducted on the current status of terrestrial vertebrates and butterflies in Garbhanga Reserve Forest. Data were compiled from field surveys and secondary sources like existing literature, and citizen science databases. We found that Garbhanga is represented by 254 species of butterflies (6 families), 29 species of amphibians (7 families), 64 species of reptiles (12 families), 307 species of birds (68 families) and 31 species of mammals (19 families). In Garbhanga, amongst the studied group, two species are ‘Critically Endangered’ (CR), six species are ‘Endangered’ (EN), 14 species are ‘Vulnerable’ (VU), eight species are ‘Near Threatened’ (NT), eight species are ‘Data Deficient’ (DD), 411 species are ‘Least Concern’ (LC), and 236 species are not assessed (denoted by blank space). This shows a huge gap in research and status evaluation of understudied species. This in turn also provides further research opportunities on the lesser known species.
Batch-produced, GIS-informed range maps for birds based on provenanced, crowdsourced data inform conservation assessments
Accurate maps of species ranges are essential to inform conservation, but time-consuming to produce and update. Given the pace of change of knowledge about species distributions and shifts in ranges under climate change and land use, a need exists for timely mapping approaches that enable batch processing employing widely available data. We develop a systematic approach of batch-processing range maps and derived Area of Habitat maps for terrestrial bird species with published ranges below 125,000 km2 in Central and South America. (Area of Habitat is the habitat available to a species within its range.) We combine existing range maps with the rapidly expanding crowd-sourced eBird data of presences and absences from frequently surveyed locations, plus readily accessible, high resolution satellite data on forest cover and elevation to map the Area of Habitat available to each species. Users can interrogate the maps produced to see details of the observations that contributed to the ranges. Previous estimates of Areas of Habitat were constrained within the published ranges and thus were, by definition, smaller-typically about 30%. This reflects how little habitat within suitable elevation ranges exists within the published ranges. Our results show that on average, Areas of Habitat are 12% larger than published ranges, reflecting the oftenconsiderable extent that eBird records expand the known distributions of species. Interestingly, there are substantial differences between threatened and non-threatened species. Some 40% of Critically Endangered, 43% of Endangered, and 55% of Vulnerable species have Areas of Habitat larger than their published ranges, compared with 31% for Near Threatened and Least Concern species. The important finding for conservation is that threatened species are generally more widespread than previously estimated. © 2021 Huang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Insights into the status and distribution of pangolins in Togo (West Africa)
Pangolins are considered among the most threatened mammal species, both globally and also in Africa. However, almost nothing is known on their status and distribution across wide areas of their range, particularly in West African countries. Here, we assess the status and distribution of pangolin species in Togo. Fieldwork was carried out in five localities around the Fazao Malfakassa National Park, five sites around the Togodo Protected Areas Complex (Togodo North and Togodo South National Parks), ‘Les Deux Béna’ and Missahohe Forest Reserves, Yikpa‐Dzigbe, Evou and Afagnan Community Forests. In all of these protected areas and forest islands, only one pangolin species was recorded: the white‐bellied pangolin (Phataginus tricuspis); we found no evidence of the giant ground pangolin (Smutsia gigantea), a species that now appears unlikely for Togo. Due to their nocturnal behaviour, we searched for pangolins by spotlighting and estimated their relative abundance using the Kilometric Index of Abundance. Our results show that P. tricuspis is still relatively abundant in suitable habitats in Fazao‐Malfakassa National Park, in Togodo North National Park and in the Assoukoko Forest Reserve. These habitats are dense remnant forest patches where numerous termite mounds and ant nests occur. The present study provides unprecedented information on the status of pangolins in Togo to help inform the development of a conservation programme for this species in this country.
Unexpected high forest turtle diversity in hill forests in northern Vietnam
Almost all Asian turtle species are considered threatened by the World Conservation Union (IUCN). We investigated the turtle fauna and their distribution in hilly forests in northern Vietnam (TamThanh commune, Quan Son district) during two consecutive periods (12th–23th May, 12th–24th August 2019). These forests are of Subtropical Moist Forest type according to WWF, and dominated by evergreen and semi-evergreen forests. We used a combination of (1) field surveys; (2) hunter interviews; (3) examination of hunter quarry, and (4) monitoring of hunting activity. We performed field surveys in bamboo and hilly secondary forests (500–1350 m), applied 103 hunter interviews, and examined the same number of hunter bags. We found a total of 124 different individuals of as many as 9 turtle species (representing 18% of the currently known total chelonian fauna in the Indo-Burma region). Two species were the most dominant, the Impressed tortoise (Manouria impressa), found mostly as shells in villages, and the Indochinese box turtle (Cuora galbinifrons) sighted inside bamboo forests at different elevations. C. galbinifrons is one of the most critically endangered turtle species in the world. Given that there are still large expanses of unexplored bamboo forests and mixed bamboo—evergreen forest (over 5 million hectares) remaining throughout northern Vietnam, if our results are typical of other similar habitats, it is likely that C. galbinifrons may be more common than currently assessed. We suggest that field surveys should be conducted as soon as possible to confirm whether these turtles are as seriously threatened as presently considered by the IUCN.
Struggles Beneath the Waves: Unveiling the Incidental Capture of Sea Turtles by Artisanal Fisheries in Angolan Waters
The modernization and intensification of fishing practices have raised the threat to sea turtles, with escalating unintentional captures endangering turtles of all life stages. In this study, we examined the impact of artisanal fishing on sea turtles in two coastal regions of Angola, southern Africa. Between August 2015 – March 2016, through participatory monitoring (n = 8) and interviews with fishers (n= 41), we documented unintentional turtle captures occurring year-round during fishing activities. A total of 405 turtles, 403 olive ridley (Lepidochelys olivacea) and 2 green (Chelonia mydas), were caught in gillnets by fishers engaged in participatory monitoring. Net characteristics, including length and proximity to the shoreline, as reported by the interviewed fishers, correlated with those used by the monitoring group. We estimated approximately 1,219 turtles captured by the 41 interviewed fishers over the 8-month study period. Most captures occurred within 100 m from the shoreline. The likelihood of accidental turtle captures increased significantly with proximity to the beach, larger mesh sizes, and greater net lengths and number of hauls. We calculated a survival rate of 41%, and a mortality rate of 59% for captured turtles. Number of turtles caught as bycatch varied throughout the year, with the highest Catch Per Unit Effort (CPUE) reported for Oct. – Dec. Since this period aligns with the nesting season, most captured turtles are likely to be females. The high mortality rate reported in this study emphasizes the immediate threat posed by accidental captures to sea turtle populations, underscoring the critical importance of conservation efforts, particularly in artisanal gillnet fisheries.