Forest Of Madagascar Research Articles

Fat storage and drought tolerance in a seasonally‐adapted primate: Implications for modeling the effects of animal responses to global climate change

AbstractGlobal warming is changing habitats and affecting biodiversity, and is expected to exacerbate aridification in many regions. Animals and plants in seasonally dry tropical forests often exhibit adaptations to cope with seasonal resource limitation. However, whether these adaptations will facilitate drought tolerance or increase drought vulnerability is unclear. Here, we combine long‐term individual‐based data on phenology, morphometrics, and demographics to investigate how drought impacts the food resources, health, reproduction, and behavior of a population of Verreaux's sifaka (Propithecus verreauxi), a critically endangered lemur inhabiting dry deciduous forests in Madagascar. Between December 2010 and May 2023, the population experienced 3 years of severe drought (2016, 2017, 2022). During green periods in severe drought, the availability of high‐quality sifaka foods (young leaves, fruit) was significantly reduced and fruit tree mortality increased. This reduced availability of fruit persisted in the year after a drought, despite typical rainfall. Yet surprisingly, we found no negative effects on body condition or commonly‐used metrics for reproductive success during drought years or years following a drought. Instead, sifaka exhibited significantly higher levels of subcutaneous body fat during severe droughts. We observed little change in sifaka behavior between drought and non‐drought periods. However, they were more likely to lick dew during severe drought, and spent significantly less time feeding on young and mature leaves. They also significantly increased their time feeding on flowers and fruits, despite the reduced abundance of fruit in the habitat. Together, our results suggest that increased consumption of water‐rich fruit and flowers during severe droughts could facilitate physiological mechanisms that help sifaka cope with water scarcity, including fructose‐mediated fat storage, metabolic water production, and water conservation. These results provide new insights into how critically endangered animals may respond to climate change, suggesting that behavioral and physiological adaptations to seasonal resource limitation may buffer some mammals from the effects of severe drought or other extreme weather events.

Contribution of small nocturnal lemurs to seed dispersal in Madagascar: A review

AbstractAnimal seed dispersers are crucial in tropical forests because they provide beneficial impacts to plants, from organisms to communities. Besides frugivorous species, omnivorous, small‐bodied, and nocturnal animals might also disperse seeds in their habitats; yet we know relatively little about their role and impacts. The Cheirogaleidae (dwarf and mouse lemurs) in Madagascar are examples of such animals, whose seed dispersal role has been overlooked until recently. Here, I provide an overview of their potential contribution to seed dispersal based on their ecological traits and future directions for studying seed dispersal ecology in Madagascar's forest ecosystems. The limited literature, published between 1971 and 2022, on the feeding ecology and seed dispersal services of the Cheirogaleidae shows that they could potentially disperse small‐sized seeds (<15 mm). Also, they could surprisingly take seeds relatively long distances away from the parents (up to 1 km) despite their small body mass, both in disturbed and undisturbed forest habitats. The passage of seeds through their guts could also enhance seed germination and seedling survival. Only four Cheirogaleid species out of 40 are currently demonstrated to be effective seed dispersers. Studying the seed dispersal by small‐bodied and nocturnal primates could greatly inform their long‐term conservation as it will provide information for better awareness of their ecological role and needs.Abstract in Malagasy is available with online material.

Topographical gradient of the structure and diversity of a woody plant community in a seasonally dry tropical forest in northwestern Madagascar

AbstractFew studies have evaluated the structure and dynamics of forests in Madagascar with high levels of endemism. Ankarafantsika National Park holds the largest of the remaining primary dry forests in northwestern Madagascar, where most of the forests have been lost or degraded by fire and other human activities. In this primary forest, we established a 15‐ha forest dynamics monitoring plot and mapped and identified all woody stems with a diameter at breast height (DBH) ≥5 cm. The forest stand was characterized by small‐sized individuals (75% of stems with DBH <10 cm, with 99% of trees with height <15 m), encompassing 35,758 tree and 513 liana individuals belonging to 160 species in 53 families (including 20 species of lianas accounting for 1.4% of the stems). Most species‐rich families were Rubiaceae, Fabaceae, Lamiaceae, and Malvaceae, which together encompassed 43 tree species and 23% of all tree individuals. The plot was located on a hill consisting of white sand at elevations from 150 to 200 m, with a gentle slope down from southwest to northeast. Over this elevation gradient, stem density and species diversity increased with elevation, while tree height and diameter decreased. The most abundant two species, Drypetes perrieri (Putranjivaceae) and Noronhia alleizettei (Oleaceae) are evergreen, suggesting the importance of a nutrient conservation strategy. These results provide the foundational knowledge necessary for the conservation and restoration of natural semi‐deciduous dry forests that used to cover large areas in northwestern Madagascar until recently.

Consistency in Verreaux's sifaka home range and core area size despite seasonal variation in resource availability as assessed by Enhanced Vegetation Index (EVI).

Primates are adept at dealing with fluctuating availability of resources and display a range of responses to minimize the effects of food scarcity. An important component of primate conservation is to understand how primates adapt their foraging and ranging patterns in response to fluctuating food resources. Animals optimize resource acquisition within the home range through the selection of resource-bearing patches and choose between contrasting foraging strategies (resource-maximizing vs. area-minimizing). Our study aimed to characterize the foraging strategy of a folivorous primate, Verreaux's sifaka (Propithecus verreauxi), by evaluating whether group home range size varied between peak and lean leaf seasons within a seasonally dry tropical forest in Madagascar. We hypothesized that Verreaux's sifaka used the resource maximization strategy to select high-value resource patches so that during periods of resource depression, the home range area did not significantly change in size. We characterized resource availability (i.e., primary productivity) by season at Kirindy Mitea National Park using remotely-sensed Enhanced Vegetation Index data. We calculated group home ranges using 10 years of focal animal sampling data collected on eight groups using both 95% and 50% kernel density estimation. We used area accumulation curves to ensure each group had an adequate number of locations to reach seasonal home range asymptotes. Neither 95% home ranges nor 50% core areas differed across peak and lean leaf resource seasons, supporting the hypothesis that Verreaux's sifaka use a resource maximization strategy. With a better understanding of animal space use strategies, managers can model anticipated changes under environmental and/or anthropogenic resource depression scenarios. These findings demonstrate the value of long-term data for characterizing and understanding foraging and ranging patterns. We also illustrate the benefits of using satellite data for characterizing food resources for folivorous primates.

New distribution records and population density of the Critically Endangered Tarzan Chameleon (Calumma tarzan), eastern Madagascar

ABSTRACT The distribution and population density of the Critically Endangered Tarzan Chameleon (Calumma tarzan) in eastern humid forests of Madagascar was studied using line transect-distance sampling. Based on the results from species distribution models, eight sites were visited over a four-month period from February 2020 to March 2021. In total, 46 transects of 1 km were investigated in 23 different forest fragments to understand the distribution of C. tarzan. Another 28 transects of 200 m in length were surveyed to estimate population density. Among the 23 investigated forest fragments, C. tarzan was confirmed from 14 fragments belonging to five sites. All 14 records are completely new and represent a significant range extension for the species. Calumma tarzan is distributed within an elevation range of 604–1048 m above sea level. An analysis of the population of the species across sites show that density varies broadly and ranges from 25 to 78 individuals per hectare. This study fills important knowledge gap on a Critically Endangered and endemic chameleon species and is vital to the development of urgently needed conservation strategy for the Tarzan Chameleon.

Forest carnivores living on the edge with invasive predators

AbstractThe proliferation of forest edges and invasive predators have been identified as two primary threats to carnivore populations globally. These threats often occur in unison, facilitated by anthropogenic activities (e.g., fragmentation), and together may pose a greater influence than when they occur separately. Targeted conservation actions for forest carnivores, including Madagascar carnivores, have been hindered by a failure to understand the relative contributions of these factors in driving species declines. To fill this gap, we conducted an extensive camera survey along the edge of intact, continuous protected rainforests in eastern Madagascar to evaluate the extent invasive predators and forest edge separately and in combination affect native carnivore space use. We hypothesized that structural vegetation changes at the forest edge interact with invasive predator trap success and occurrence to reduce native carnivore space use near the forest edge and separately have less influence than when combined. In contrast to findings in fragmented and degraded forests of Madagascar, we found hard forest edge and invasive predators alone do not indiscriminately reduce native carnivore space use in continuous intact forest. Instead, we found free‐roaming dogs and cats interact with their surrounding environment (i.e., forest edge) in unique ways that shape species response differently than within interior forest. At the forest edge, vegetational changes of increasing shrub cover and the occurrence of dogs reduce space use of three of four native carnivores. However, we found greater effects of proximity to villages, especially with high invasive predator activity (free‐roaming cats). Ultimately, native carnivores showed variable sensitivities to pressures we examined, providing support for species‐specific management actions to maximize conservation outcomes. We encourage future studies to consider evaluating the magnitude of separate and combined threats to carnivores. In doing so, conservationists can better identify when threats can be managed in isolation and when they require simultaneous mitigation.

Fire incongruities can explain widespread landscape degradation in Madagascar's forests and grasslands

Societal Impact StatementThe relationship between rainfall, fire and habitat can display incongruencies. The 2021 Malagasy Grassy Biomes Workshop identified understanding fire regimes as a knowledge gap. This study pinpoints regions where anthropogenic fire has the potential to transform or has transformed habitat to treeless‐grassland, by identifying landscape‐scale, island‐wide fire anomalies across half of Madagascar. Its eastern forests burn like savannas, and central‐western grasslands burn frequently and intensely despite receiving rainfall usually associated with forest and fire‐absence. Recognising the incongruity and better understanding its drivers can mitigate against landscape‐scale degradation, improving ecological function, and human well‐being.Summary Data show that since 1953, human‐lit fires on Madagascar have transformed clear‐cut forest to treeless‐grasslands. To address the extent of Malagasy treeless‐grasslands at human settlement, the 2021 Malagasy Grassy Biomes Workshop identified the role of fire as a critical knowledge‐gap for understanding ecological function. The relationship between mean annual precipitation (MAP), fire and habitat is well established across mesic systems. Anthropogenically transformed habitats often deviate from expected ecological patterns, so we tested for landscape‐scale, island‐wide MAP‐related fire and habitat anomalies. We collated Malagasy fire, habitat and MAP datasets, identifying location and scale of incongruities relative to global fire‐habitat‐MAP expectations. Next, we tested for mismatches in fire regimes (frequency, timing, extent and intensity of fires) between Malagasy and equivalent global biomes, using global, comprehensive landscape‐scale fire regime data. Across half of Madagascar, fire frequency and habitat are decoupled from MAP, and fire regimes across Malagasy ecoregions differ significantly from those in shared biomes elsewhere in the world. Landscape‐scale incongruities span Malagasy eastern forests (which burn like savanna systems) and central‐western treeless‐grasslands, which burn frequently and intensely despite receiving MAP typical of forest presence and fire‐absence, globally. Fire‐MAP incongruities identify potentially transformed areas, or those undergoing transformation by fire, and establish a platform for investigating the nuanced social, political and ecological dynamics that may contribute to and perpetuate these anomalies. Incongruities also highlight the anthropogenic landscape degradation associated with fire anomalies. Addressing these impacts can facilitate restoration of ecological function, productivity and food security, benefiting biodiversity and humans at multiple scales.

A TAXONOMIC REVISION OF THE MADAGASCAR-ENDEMIC GENUS BEMANGIDIA (SAPOTACEAE), WITH DESCRIPTION OF A SECOND SPECIES

Bemangidia L.Gaut. (Sapotaceae) is a genus endemic to a restricted area in the southeastern lowland moist evergreen forests of Madagascar. It was published in 2013 to accommodate an undescribed species, Bemangidia lowryi L.Gaut., which showed a combination of characters unique in the family Sapotaceae. At the time of description, three atypical collections from the same locality but growing on a ridge, slightly higher in altitude, were already known. Although matching well with the Bemangidia genus, they were phenotypically different from B. lowryi and were therefore not included in the species description. In the present study, we evaluate whether these specimens correspond to a new species, using a combination of morphological and genetic data based on 638 nuclear genes. The results show that Bemangidia contains two lineages, each one corresponding to a different morphology, with a genetic branch length similar to those observed among species pairs in other genera of Sapotaceae. We conclude that the genetic and morphological differences are sufficient to consider the two lineages as two distinct species. Consequently, the genus is here revised and a second species described.

Nutritional and Possible Pharmaceutical Aspects of Tree Exudates Eaten by Lemurs of Madagascar’s Dry Forests

Gums produced by trees after injuries are valuable food resources for several primate species. Yet, information on the chemical characteristics of gum is scant and inconsistent. We use gums consumed by lemurs (strepsirrhine primates of Madagascar) as an example to illustrate their possible nutritive and pharmaceutical properties. Exudates from 45 tree species of the dry forests of Madagascar contained 0.38–23.29% protein, 0.46–65.62% sugar, and 0.39–11.86 kJ/g of energy in dry matter. Exemplified by the lemur species Microcebus griseorufus, gum consumption increased with increasing sugar and energy content but was unrelated to protein. But lemurs also fed on gum with very low protein and energy content, suggesting that these exudates were consumed for other reasons. Disk diffusion tests with exudates from five out of 22 tree species consumed by lemurs showed antibacterial activity against Micrococcus spp. and/or Staphylococcus aureus. Exudates with antibacterial activity had lower protein, sugar, and energy contents than samples without antibacterial properties. GC-MS analyses revealed several components with antimicrobial effects that would have the potential for self-medication. This might explain the consumption of gum with very low nutritive value. Possible medicinal effects of tree exudates deserve further attention in view of their pharmaceutical applicability for animals and humans alike.

Effects of forest fragmentation on the dietary ecology and activity of a nocturnal lemur communityin North West Madagascar.

Deforestation and habitat fragmentation is the primary threat to primate populations. The primates that live within degraded and anthropogenically disturbed habitats typical of fragmented landscapes have to cope with lower availability of resources in comparison to primates in continuous, undisturbed forests. While some species are sensitive to forest fragmentation, some evidence exists to suggest that primates can alter their behavior and adapt to such changes, which enables their survival in suboptimal habitat. In this study, we assessed how forest fragmentation and its associated edge-effects impact the feeding ecology and activity levels of a nocturnal primate community in the Sahamalaza-Iles Radama National Park, North West Madagascar. From March 06, 2019 to May 17, 2022, we collected data on tree and invertebrate phenology at our study site, and feeding ecology and activity for 159 lemur individuals from four species. Fruit and flower availability varied significantly between continuous and fragmented forest, and between forest core and edge areas, with continuous forest exhibiting higher continuous fruit and flower availability. Lemur feeding ecology varied significantly too, as the feeding niches of all four species were significantly different between continuous and fragmented forest and between core and edge areas. However, lemur activity levels were mostly consistent among all forest areas. The results of this study suggest that nocturnal lemurs are able to adapt their dietary ecology in response to the available food sources within their habitat. Due to this flexible ecology and dietary plasticity, the lemurs do not need to significantly alter their behavior in different environments to fulfill their dietary needs. While nocturnal lemurs demonstrate adaptability and flexibility to degraded habitat, it is unclear how far this plasticity will stretch considering that Madagascar's forests are still being cleared at an alarming rate. Urgent conservation action is therefore needed to ensure the future of lemur habitat.

Seasonal variation in glucose and insulin is modulated by food and temperature conditions in a hibernating primate.

Feast-fast cycles allow animals to live in seasonal environments by promoting fat storage when food is plentiful and lipolysis when food is scarce. Fat-storing hibernators have mastered this cycle over a circannual schedule, by undergoing extreme fattening to stockpile fuel for the ensuing hibernation season. Insulin is intrinsic to carbohydrate and lipid metabolism and is central to regulating feast-fast cycles in mammalian hibernators. Here, we examine glucose and insulin dynamics across the feast-fast cycle in fat-tailed dwarf lemurs, the only obligate hibernator among primates. Unlike cold-adapted hibernators, dwarf lemurs inhabit tropical forests in Madagascar and hibernate under various temperature conditions. Using the captive colony at the Duke Lemur Center, we determined fasting glucose and insulin, and glucose tolerance, in dwarf lemurs across seasons. During the lean season, we maintained dwarf lemurs under stable warm, stable cold, or fluctuating ambient temperatures that variably included food provisioning or deprivation. Overall, we find that dwarf lemurs can show signatures of reversible, lean-season insulin resistance. During the fattening season prior to hibernation, dwarf lemurs had low glucose, insulin, and HOMA-IR despite consuming high-sugar diets. In the active season after hibernation, glucose, insulin, HOMA-IR, and glucose tolerance all increased, highlighting the metabolic processes at play during periods of weight gain versus weight loss. During the lean season, glucose remained low, but insulin and HOMA-IR increased, particularly in animals kept under warm conditions with daily food. Moreover, these lemurs had the greatest glucose intolerance in our study and had average HOMA-IR values consistent with insulin resistance (5.49), while those without food under cold (1.95) or fluctuating (1.17) temperatures did not. Remarkably low insulin in dwarf lemurs under fluctuating temperatures raises new questions about lipid metabolism when animals can passively warm and cool rather than undergo sporadic arousals. Our results underscore that seasonal changes in insulin and glucose tolerance are likely hallmarks of hibernating mammals. Because dwarf lemurs can hibernate under a range of conditions in captivity, they are an emerging model for primate metabolic flexibility with implications for human health.

Revision of the Subgenus Ochthomantis Frogs from Madagascar (Amphibia: Mantellidae) with the Description of Four Species and Resurrection of Mantidactylus catalai and M. poissoni.

The subgenus Ochthomantis is an obligate forest and stream-dwelling group of mantellid frogs, endemic to Madagascar, with six species currently recognized. However, this group suffers from ongoing taxonomic confusion due to low numbers of examined specimens, and failure to consider morphological variation from development and sexual dimorphism. Here, we examined the morphology of 637 sexed adult specimens collected by us in the field and from other museum collections. We also sequenced a DNA fragment of the 16S mtDNA gene for each lineage to determine congruence between morphological and molecular data sets and to help delimit species. Our results demonstrate that the subgenus Ochthomantis includes eleven valid species: five already recognized, M. catalai and M. poissoni that we resurrect from synonymy, and four new species which we describe for the first time here. In some analyses, Mantidactylus majori groups with other Mantidactylus subgenera, so we do not consider it a member of the subgenus Ochthomantis in this study. All species have restricted distributions and elevational ranges in the humid forests of Madagascar. This study demonstrates the utility of assessing cryptic species using both diagnostic morphological characters and molecular data. The discovery of this new cryptic biodiversity, and the taxonomic revision herein, will likely require conservation activities for those species with the most restricted distributions.

DNA‐based fungal diversity in Madagascar and arrival of the ectomycorrhizal fungi to the island

AbstractMadagascar is known for its high diversity and endemism of fauna and flora. Fungi, however, have been largely overlooked in diversity and evolution studies on the island, and whether fungi exhibit the same patterns as animals and plants has yet to be further examined. We collected fungal sporocarps and ectomycorrhizal (EcM) roots during three opportunistic surveys in five forests in Madagascar and generated a dataset of fungal Internal Transcribed Spacer (ITS) DNA sequences. We analyzed them together with all publicly available fungal ITS DNA sequences and identified 620 Operational Taxonomic Units (OTUs) from Madagascar, 10% of which contained only sequences from our surveys. Two hundred and ninety‐two OTUs belonged to EcM species with /russula‐lactarius, /boletus, /tomentella‐telephora, /cortinarius, and /amanita being the most abundant EcM lineages. Overall, 60% of all fungi and 81% of the EcM species from Madagascar appear to be endemic. We conducted a phylogenetic analysis using all the OTUs in Amanitaceae, Boletaceae, and Russulaceae families to elucidate their relative timing of arrival in Madagascar. We found that most EcM species from Madagascar in the three families diverged less than 22 million years ago (mya), long after the separation of India and Madagascar (88 mya), which is consistent with a dispersal mediated process of arrival to the island. Our study provides the first comprehensive view of the overall DNA‐based fungal diversity in Madagascar and the current state of knowledge of EcM fungi based on DNA sequences, useful for further ecological and evolutionary studies.Abstract in Malagasy is available with online material.

Tree canopy density thresholds for improved forests cover estimation in protected areas of Madagascar

Abstract The rich endemic biodiversity of Madagascar is concentrated in different types of natural forests primarily conserved within the network of protected areas (PAs). Since 1990, remote sensing has been utilized to monitor forest cover. The latest forest cover map generated using these techniques provides accurate estimates of natural forest cover within the PAs network. However, the standardized application of Tree Canopy Density (TCD), as used in global assessments of forest cover, yields erroneous estimates for different forest types in Madagascar because the standard TCD cannot be globally applied to all types of forests. Our study aims to utilize global remote sensing data at the scale of PAs to identify specific TCD thresholds for individual PAs. Starting from the year 2000 data, the application of these thresholds will allow us to estimate deforestation in subsequent years at reduced costs. We used the official PA boundaries, a reliable forest cover map at the national scale, and the TCDs published at a global scale to infer the values of TCD to be applied in each PA. The standard TCD threshold above 30% overestimates humid and dry forests and underestimates dry spiny forests in Madagascar. Our specific TCD thresholds inferred for each PA accurately estimate the forest cover in the vast majority of PAs. Using these specific TCD thresholds will allow for improved monitoring of forest cover within the network of PAs. The methodology detailed here can also be applied in other geographic regions, and future improvements in data on forest cover—both remotely sensed and field-collected—will enhance our ability to estimate forest cover and its changes over time.

Host-related and environmental factors influence long-term ectoparasite infestation dynamics of mouse lemurs in northwestern Madagascar.

Parasite infestations depend on multiple host-related and environmental factors. In the case of ectoparasites, which are exposed to the environment beyond the host, an impact of climate, expressed by seasonal or yearly variations, can be expected. However, long-term dynamics of ectoparasite infestations are rarely studied in nonhuman primates. We investigated the yearly variations in ectoparasite infestations of two small primates, the gray (Microcebus murinus) and the golden-brown (Microcebus ravelobensis) mouse lemur. For a more comprehensive evaluation, we also analyzed the potential effects of yearly and monthly climatic variation (temperature, rainfall) in addition to habitat, host sex, age, species, and body mass, on ectoparasite infestation. Individuals of both host species were sampled in two study sites within the Ankarafantsika National Park in northwestern Madagascar during several months (March-November) and across 4 years (2010, 2011, 2015, 2016). Our results show significant monthly and yearly variations in the infestation rates of three native ectoparasite taxa (Haemaphysalis spp. ticks, Schoutedenichia microcebi chigger mites, Lemurpediculus spp. sucking lice) and in ectoparasite species richness in both mouse lemur species. In addition, significant impacts of several host-related (species, sex, body mass) and environmental factors (habitat, temperature, rainfall) were found, but with differences in relevance for the different parasite taxa and partly deviating in their direction. Although some differences could be attributed to either permanent or temporary presence of the parasites on the host or to ecological differences between the host species, the lack of specific knowledge regarding the life cycle and microhabitat requirements of each parasite taxon precludes a complete understanding of the factors that determine their infestation dynamics. This study demonstrates the presence of yearly and monthly dynamics in lemur-parasite interactions in tropical, seasonal, dry deciduous forests in Madagascar, which call out for broad ecological long-term studies focusing both on primate hosts and their parasites.

Habitat and ecological niche characteristics of the elusive Hairy-eared Dwarf Lemur (Allocebus trichotis) with updated occurrence and geographic range data.

Ecological niche modeling (ENM) is particularly useful in the study of cryptic and elusive species that are only rarely seen, difficult to study in the wild, and simultaneously threatened by a multitude of anthropogenic factors. We collected presence records one such example, the understudied Hairy-eared Dwarf Lemur (Allocebus trichotis), from the literature and supplemented these with observations from surveys in previously unstudied areas to model its fundamental and realized niche throughout Madagascar. We further evaluated habitat characteristics at each sighting location to judge its conservation status and its adaptability towardhabitat degradation. We found 31 presence localities in the literature and directly observed A. trichotis a further 23 times. According to the ENMs, precipitation of the driest quarter and maximum temperature of the warmest month mostly influenced its distribution, restricting it to the higher altitudes of the northeastern humid forests of Madagascar. Its fundamental niche, extent of occurrence, and area of occupancy were estimated as 65,819, 53,054, and 16,967 km²respectively. The latter, however, declined by 29.2% since 1990. On a habitat level, it was most often observed in primary forest habitats of different degradation stages (85.7%, n = 21). The fundamental niche of A. trichotis is most likely restricted by climatic factors. Although it can be found in moderately degraded forests, it is known to depend on the availability of tree holes and therefore old-growth forest structures. Ongoing deforestation and habitat fragmentation are likely to be the major threats to the survival of this species. Our ENMs provide evidence on where to intensify survey efforts on the elusive Hairy-eared Dwarf Lemurs of Madagascar.

Vanilla Bats: Insectivorous Bat Diversity in the Vanilla Agroecosystems of Northeastern Madagascar

Due to global agricultural expansion and intensification, many animal species must now survive within a landscape dominated by agroecosystems. For bats, agroecosystems can provide a valuable foraging-habitat, and many species of bats thrive within such habitats whilst also providing a range of ecosystem services for farmers. Despite this, bat usage of many agroecosystem types remains unstudied. Here, we investigated the diversity of insectivorous bats in the vanilla agroecosystems of northeastern Madagascar, the world's principal vanilla-growing region. To assess bat diversity, we used a passive acoustic survey technique, and we identified and classified bat species diversity using PCA and DFA analysis of echolocation call acoustic parameters. In total, we were able to detect the presence of at least 13 different bat species within Madagascar's vanilla agroecosystems, seven of which we were able to confidently identify to species level. However, due to our conservative classification approach, the true diversity of bats in vanilla agroecosystems is likely to be higher. The results of this study indicate that Madagascar's vanilla agroecosystems represent suitable foraging habitat for numerous bat species, particularly forest-specialists, which is a highly encouraging finding for the conservation of Madagascar's bats. Expansion of vanilla agroecosystems is therefore likely to provide valuable habitat extensions for Madagascar's forest bats in the future, provided this expansion does not come at the expense of existing largely-undisturbed natural habitats.

Quali-Quantitative Fingerprinting of the Fruit Extract of Uapaca bojeri Bail. (Euphorbiaceae) and Its Antioxidant, Analgesic, Anti-Inflammatory, and Antihyperglycemic Effects: An Example of Biodiversity Conservation and Sustainable Use of Natural Resources in Madagascar.

Antioxidants are important supplements for the human body for their roles in human life for the maintenance of homeostasis. Tapia fruits (Uapaca bojeri) are used by the riverain population of the Tapia forests in Madagascar as complementary foods. This study aims to quantify the main antioxidants in the U. bojeri fruits to verify their contribution to the enhancement of their anti-inflammatory and antihyperglycemic effects. Standard phytochemical screening was used for qualitative analysis, while spectrophotometric (TPC, TAC, and TFC) and chromatographic analyses (HPLC) were used to quantify several phytochemicals in U. bojeri fruits. The antioxidant activity was evaluated using DPPH and FRAP assays. The writhing test was used for the analgesic effects, the carrageenan-induced paw edema was used for the anti-inflammatory activity, and OGTT was used to test the anti-hyperglycemia property of the MEUB in mice. Several phytocompounds were detected and quantified in the fruits, including succinic acid (67.73%) as the main quantified compound. Fruits exerted a good antioxidant capacity and showed analgesic, anti-inflammatory, and antihyperglycemic activities in mice. Isolation of the bioactive compounds should be carried out to confirm these pharmacological properties and develop health-promoting food products or medicinal applications derived from this species.

Spontaneous neoplasms in captive red-bellied lemurs (Eulemur rubriventer)

Red-bellied lemurs (Eulemur rubriventer: genus Eulemur, family Lemuridae, Suborder Strepsirrhini) are non-human primates endemic to the forests of Madagascar and listed as 'vulnerable' on the IUCN Red List of Threatened Species. Currently, descriptions of neoplasia in this species are extremely scarce, with only one case of hepatocellular adenoma reported. Prosimian submissions received by the Anatomic Pathology Service at North Carolina State University from January 2010 to January 2021 were retrieved. A total of 200 cases of Strepsirrhini prosimians were identified, representing 57 (28.5%) individuals from the genus Eulemur of which seven (12.3%) cases were red-bellied lemurs. Neoplasia was identified in two of the seven (28.57%) cases. The first case was a 25-year-old, intact female with hepatocellular carcinoma and the second a 33-year-old, intact female with a cervical mass consistent with osteoblastic osteosarcoma arising from the left clavicular bone. Hepatocellular neoplasms are commonly reported in prosimians, with carcinomas more frequent than adenomas. In contrast, osteosarcoma has been rarely described in lemuriformes, with four cases reported. To our knowledge, this is the first report of osteosarcoma and hepatocellular carcinoma in a red-bellied lemur.

The eco‐evolutionary history of Madagascar presents unique challenges to tropical forest restoration

AbstractHigh biodiversity and endemism combined with persistently high deforestation rates mark Madagascar as one of the hottest biodiversity hot spots. Contemporary rising interest in large‐scale reforestation, both globally and throughout Madagascar itself, presents a promising impetus for forest restoration and biodiversity conservation across the island. However, Madagascar may face unique restoration challenges due to its equally unique eco‐evolutionary trajectory, which must be understood to enable successful ecological restoration. We conducted a systematic review of potential barriers to restoration for terrestrial forest biomes (rain forests, dry forests, and subhumid highland forests) in Madagascar. Our results indicate that aboveground biomass recovery of Malagasy forests appears to be slower than other tropical forests. We suggest four key synergistic factors that inhibit restoration in Madagascar: (a) lack of resilience to shifting nutrient and fire regimes arising from widespread high‐intensity shifting cultivation; (b) predominance of nutrient‐poor, highly weathered ferralitic soils; (c) vulnerability of regenerating native trees to competition with invasive species due to their evolutionary isolation; and (d) low seed dispersal into regenerating forests due to the unique dependence of Malagasy trees on dispersal by forest‐dependent endangered or extinct primates. However, we note that rigorous experimental study of regenerating forests in Madagascar is currently lacking. There are great opportunity and need for such research to disentangle drivers and interactions inhibiting forest restoration. These studies would enable reforestation practitioners to effectively capitalize on current global momentum to implement the large‐scale restoration necessary for the conservation of Madagascar's numerous endemic species.Abstract in Malagasy is available with online material