Faunal inventories are essential to understanding distribution patterns, as well as informing and... more Faunal inventories are essential to understanding distribution patterns, as well as informing and prioritizing conservation actions. Lemurs are charismatic taxa, used not only as umbrella and flagship species but also as predictors of community richness and models of the diversification processes in Madagascar. The Vohimana Reserve is located in the heart of the Ankeniheny-Zahamena corridor, one of Madagascar’s conservation priorities, and hosts a mid-altitude rainforest. The forest has long faced strong anthropogenic disturbances, such as slash-and-burn agriculture, logging, and poaching. Prior to this study, no long-term study on the lemur community in Vohimana had been conducted and no updated information was available. We aimed to provide a lemur inventory and a description of threats that could be used by forest managers in order to inform and optimize future conservation plans. Between April and December 2018, we surveyed the forest using line-transect distance sampling. Our results show that Vohimana is home to 11 lemur species, including two critically endangered species (Indri indri and Propithecus diadema). We found no evidence of the presence of the black-and-white ruffed lemur (Varecia variegata), which was once reported to inhabit the forest. The possible disappearance of this species, the low frequency of Lemuridae species observations, and the observation of snares, selective logging, and charcoal production suggest actions and long-term monitoring are urgently needed in order to protect this fragile but strategic ecosystem.
Habitat loss and poaching are among the most serious threats to the fragile and unique biodiversi... more Habitat loss and poaching are among the most serious threats to the fragile and unique biodiversity of Madagascar. In the past, traditional taboos (fady), commonly associated with folk stories, have had a buffering effect on several lemur species. Here, we examine the status of hunting taboos with reference to the conservation of the critically endangered Perrier's sifaka (Propithecus perrieri). We also provide an update on P. perrieri’s presence in the protected area of Andrafiamena in the face of ongoing habitat fragmentation and poaching. The Andrafiamena forest represents one of the key refuges for this species, which has a very limited and fragmented range in northern Madagascar. We report the results of a 2016 presence/absence survey in Andrafiamena and from interviews on Perrier’s sifaka taboo adherence, conducted in 2012 across the whole species range. Our results confirm the presence of Perrier’s sifakas in Andrafiamena and that in 2012, across the species’ range, the hunting taboo was observed by most (>95%) interviewees who answered (N = 23). Forest clearing and a decrease of taboo adherence may intensify the pressure on the already small and fragile population of P. perrieri. A deeper knowledge of the human-wildlife interconnections, as well as regular monitoring of this rare species’ distribution, may be crucial for the success of its conservation.
Tree hollows provide shelters for a large number of forest-de-
pendent vertebrate species worldwi... more Tree hollows provide shelters for a large number of forest-de- pendent vertebrate species worldwide. In Madagascar, where high historical and ongoing rates of deforestation and forest degrada- tion are responsible for a major environmental crisis, reduced availability of tree hollows may lead to declines in hollow-dwelling species such as sportive lemurs, one of the most species-rich groups of lemurs. The identification of native tree species used by hollow-dwelling lemurs may facilitate targeted management inter- ventions to maintain or improve habitat quality for these lemurs. During an extensive survey of sportive lemurs in northern Mada- gascar, we identified one tree species, Strychnos madagascarien- sis (Loganiaceae), the spineless monkey orange tree, as a principal sleeping site of two species of northern sportive lemurs, Lepile- mur ankaranensis and L. milanoii (Lepilemuridae). This tree spe- cies represented 32.5% (n=1 50) of the 458 sleeping sites recorded. This result suggests that S. madagascariensis may be valuable for the conservation of hollow-dwelling lemurs.
The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confin... more The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confined to the Loky-Manambato region . Very little is known about L. milanoii and it is classified as "Data Deficient" by the IUCN . Despite the management of the area by the NGO Fanamby since 2005, no study had been conducted to determine the presence and the abundance of L. milanoii in the main forest fragments of the region. During the 2011 dry season we surveyed the ten main forest fragments of the Loky-Manambato region and estimated L. milanoii densities and population sizes using line transect distance sampling and the DISTANCE software . The results suggest that sportive lemur densities are reasonably high in the region, but with important discrepancies between forest fragments, with densities ranging from 49.8 ind./km² in Antsaharaingy to 590.5 ind./km² in Ampondrabe. For the region Loky-Manambato we were able to estimate a population size of ~52,000 individuals. This is the first estimate for the total population size and we argue that similar studies should be repeated to monitor environmental changes and anthropogenic pressures (hunting, deforestation, mining, etc.).
Propithecus perrieri (Perrier's sifaka) is one of the most endangered lemur species due to its 27... more Propithecus perrieri (Perrier's sifaka) is one of the most endangered lemur species due to its 27 small and fragmented distribution range. Despite a critically endangered (CR) conservation 28 and flagship species status, there are still many uncertainties regarding its actual distribution 29 and its presence in some forests of its putative distribution range. We report the results of 30 diurnal and nocturnal surveys carried out in 2012 across most forest fragments of its putative 31 distribution range, namely the Ankarana National Park, the Analamerana Special Reserve and 32
Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats mon... more Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats montrent que les densités de microcèbes sont relativement élevées, et varient de 28 à 325 ind/km² entre fragments forestiers de la région. Des études plus approfondies des données collectées seront nécessaires pour déterminer les variables environnementales responsables des différences de densité observées.
Developing Coffea arabica seeds accumulate large amounts of chlorogenic acids (CGAs) as a storage... more Developing Coffea arabica seeds accumulate large amounts of chlorogenic acids (CGAs) as a storage form of phenylpropanoid derivatives, making coffee a valuable model to investigate the metabolism of these widespread plant phenolics. However, developmental and environmental regulations of CGA metabolism are poorly understood. In the present work, the expression of selected phenylpropanoid genes, together with CGA isomer profiles, was monitored throughout seed development across a wide set of contrasted natural environments. Although CGA metabolism was controlled by major developmental factors, the mean temperature during seed development had a direct impact on the time-window of CGA biosynthesis, as well as on final CGA isomer composition through subtle transcriptional regulations. We provide evidence that the variability induced by the environment is a useful tool to test whether CGA accumulation is quantitatively modulated at the transcriptional level, hence enabling detection of rate-limiting transcriptional steps [quantitative trait transcripts (QTTs)] for CGA biosynthesis. Variations induced by the environment also enabled a better description of the phenylpropanoid gene transcriptional network throughout seed development, as well as the detection of three temporally distinct modules of quantitatively co-expressed genes. Finally, analysis of metabolite-to-metabolite relationships revealed new biochemical characteristics of the isomerization steps that remain uncharacterized at the gene level.
The seed of Coffea arabica accumulates large amounts of cell wall storage polysaccharides (CWSPs)... more The seed of Coffea arabica accumulates large amounts of cell wall storage polysaccharides (CWSPs) of the mannan family in the cell walls of the endosperm. The variability induced by the growing environment and extensive pairwise correlation analysis with stringent significance thresholds was used to investigate transcript-transcript and transcript-metabolite relationships among 26 sugar-related genes, and the amount of CWSPs and seven soluble low molecular weight carbohydrates in the developing coffee endosperm. A dense module of nine quantitatively co-expressed genes was detected at the mid-developmental stage when CWSPs accumulate. This module included the five genes of the core galactomannan synthetic machinery, namely genes coding for the enzymes needed to assemble the mannan backbone (mannan synthase, ManS), and genes that introduce the galactosyl side chains (galactosyltransferase, GMGT), modulate the post-depositional degree of galactose substitution (α-galactosidase), and produce the nucleotide sugar building blocks GDP-mannose and UDP-galactose (mannose-1P guanyltransferase and UDP-glucose 4'-epimerase, respectively). The amount of CWSPs stored in the endosperm at the onset of their accumulation was primarily and quantitatively modulated at the transcriptional level (i.e. positively correlated with the expression level of these key galactomannan biosynthetic genes). This analysis also suggests a role for sorbitol and raffinose family oligosaccharides as transient auxiliary sources of building blocks for galactomannan synthesis. Finally, a microarray-based analysis of the developing seed transcriptome revealed that all genes of the core galactomannan synthesis machinery grouped in a single cluster of 209 co-expressed genes. Analysis of the gene composition of this cluster revealed remarkable functional coherence and identified transcription factors that putatively control galactomannan biosynthesis in coffee.
The crowned sifaka (Propithecus coronatus) is Endangered. It has a large but highly fragmented di... more The crowned sifaka (Propithecus coronatus) is Endangered. It has a large but highly fragmented distribution; its known range extends from the Betsiboka River in the north of Madagascar, to the Mahavavy River in the north-west, and down to the Tsiribihina River in the south-west. The species lives in forest habitats that are highly and increasingly fragmented and are continuously suffering perturbations and destruction. In order to carry out effective conservation measures targeting P. coronatus, its conservation status needs to be updated so that measures can be taken before anthropogenic or natural environmental changes lead to the extirpation of the species in most of its forests. We (i) identified forest fragments where the species is still present and (ii) using the line-transect "Distance" sampling method, estimated the population size and density in the principal remaining forest fragments in the northern part of its range, including both protected and unprotected areas. We visited most of the forests in the northern part of its range in order to update the current area of occupancy, and to rate the state of its forests using a qualitative "forest quality index." Our survey results have shown that (i) a large number of forests have disappeared or decreased in size in the last 10 years, and (ii) population densities vary considerably among forest fragments (ranging from 49 to 309 individuals per km²), with some very high densities in forests located along the Mahavavy River and in the Antrema area. Their abundance in the area surveyed is likely to be between 4,226 and 36,672 individuals, and most probably above 10,000. It is difficult to extrapolate from these estimates to the total abundance across the species' entire range, but we estimate that it is likely to be large, probably between 130,000 and 220,000 individuals. Unfortunately, many field observations suggest that its populations continue to decline at a high rate due to habitat loss and hunting, and we argue for the re-evaluation of the conservation status from Endangered A2cd to Endangered A4acd, and the need to survey the rest of the range of P. coronatus.
Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite i... more Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite its Endangered (EN) IUCN conservation status, uncertainties persist regarding its actual distribution and its presence in forests that are thought to be part of its distribution range. We provide here the first extensive population surveys of Coquerel's sifaka across a large number of forest fragments neighboring 27 sites of its known and expected distribution range in northwestern Madagascar, including 12 previously visited sites. During our diurnal surveys carried out in the dry seasons from 2009 to 2011 we observed the species in 26 of the 27 visited sites. Combining our results with previously published data, we propose a refined update of the species' distribution range and identify areas to be surveyed. We also recorded the support tree species on which sifakas were observed, and note that, surprisingly, P. coquereli was frequently seen around villages and in areas dominated by introduced tree species. Although the species was present at almost all the visited sites of its highly fragmented distribution range, it remains unclear how viable the populations of a significant proportion of these sites actually are. Due to political instability and high rates of deforestation, large-scale conservation actions are urgently needed. We thus (1) discuss the outline of a possible metapopulation conservation action plan for P. coquereli and (2) identify priority sites and actions.
Rajaonson, A.; Ratolojanahary, T.; Rafalimandimby, J.; Fanomezantsoa, P.; Ramahefasoa, B.; Rasolo... more Rajaonson, A.; Ratolojanahary, T.; Rafalimandimby, J.; Fanomezantsoa, P.; Ramahefasoa, B.; Rasolofoharivelo, T.; Ravaloharimanitra, M.; Ratsimbazafy, J.; Dolch, R.; King, T. 2011. New distributional records and conservation implications for the critically endangered greater bamboo lemur Prolemur simus. Folia Primatologica 82 (2): 118-129. Randrianarimanana, L.; Ravaloharimanitra, M.; Ratolojanahary, T.; Rafalimandimby, J.; Rasolofoharivelo, T.; Ratsimbazafy, J.; Dolch, R.; King, T. 2012. Statut et conservation de Prolemur simus dans les sites de Ranomainty et Sakalava du Corridor Ankeniheny-Zahamena. Lemur News 16: 2-7. Ravaloharimanitra, M.; Ratolojanahary, T.; Rafalimandimby, J.; Rajaonson, A.; Rakotonirina, L.; Rasolofoharivelo, T.; Ndriamiary, J.N.; Andriambololona, J.; Nasoavina, C.; Fanomezantsoa, P.; Rakotoarisoa, J.C.; Youssouf; Ratsimbazafy, J.; Dolch, R.; King, T. 2011. Gathering local knowledge in Madagascar results in a major increase in the known range and number of sites for critically endangered greater bamboo lemurs (Prolemur simus).
Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats mon... more Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats montrent que les densités de microcèbes sont relativement élevées, et varient de 28 à 325 ind/km² entre fragments forestiers de la région. Des études plus approfondies des données collectées seront nécessaires pour déterminer les variables environnementales responsables des différences de densité observées.
The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confin... more The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confined to the Loky-Manambato region . Very little is known about L. milanoii and it is classified as "Data Deficient" by the IUCN . Despite the management of the area by the NGO Fanamby since 2005, no study had been conducted to determine the presence and the abundance of L. milanoii in the main forest fragments of the region. During the 2011 dry season we surveyed the ten main forest fragments of the Loky-Manambato region and estimated L. milanoii densities and population sizes using line transect distance sampling and the DISTANCE software . The results suggest that sportive lemur densities are reasonably high in the region, but with important discrepancies between forest fragments, with densities ranging from 49.8 ind./km² in Antsaharaingy to 590.5 ind./km² in Ampondrabe. For the region Loky-Manambato we were able to estimate a population size of ~52,000 individuals. This is the first estimate for the total population size and we argue that similar studies should be repeated to monitor environmental changes and anthropogenic pressures (hunting, deforestation, mining, etc.).
Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite i... more Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite its Endangered (EN) IUCN conservation status, uncertainties persist regarding its actual distribution and its presence in forests that are thought to be part of its distribution range. We provide here the first extensive population surveys of Coquerel's sifaka across a large number of forest fragments neighboring 27 sites of its known and expected distribution range in northwestern Madagascar, including 12 previously visited sites. During our diurnal surveys carried out in the dry seasons from 2009 to 2011 we observed the species in 26 of the 27 visited sites. Combining our results with previously published data, we propose a refined update of the species' distribution range and identify areas to be surveyed. We also recorded the support tree species on which sifakas were observed, and note that, surprisingly, P. coquereli was frequently seen around villages and in areas dominated by introduced tree species. Although the species was present at almost all the visited sites of its highly fragmented distribution range, it remains unclear how viable the populations of a significant proportion of these sites actually are. Due to political instability and high rates of deforestation, large-scale conservation actions are urgently needed. We thus (1) discuss the outline of a possible metapopulation conservation action plan for P. coquereli and (2) identify priority sites and actions.
The global loss of biodiversity continues at an alarming rate. Genomic approaches have been sugge... more The global loss of biodiversity continues at an alarming rate. Genomic approaches have been suggested as a promising tool for conservation practice as scaling up to genome-wide data can improve traditional conservation genetic inferences and provide qualitatively novel insights. However, the generation of genomic data and subsequent analyses and interpretations remain challenging and largely confined to academic research in ecology and evolution. This generates a gap between basic research and applicable solutions for conservation managers faced with multifaceted problems. Before the real-world conservation potential of genomic research can be realized, we suggest that current infrastructures need to be modified, methods must mature, analytical pipelines need to be developed, and successful case studies must be disseminated to practitioners.
Faunal inventories are essential to understanding distribution patterns, as well as informing and... more Faunal inventories are essential to understanding distribution patterns, as well as informing and prioritizing conservation actions. Lemurs are charismatic taxa, used not only as umbrella and flagship species but also as predictors of community richness and models of the diversification processes in Madagascar. The Vohimana Reserve is located in the heart of the Ankeniheny-Zahamena corridor, one of Madagascar’s conservation priorities, and hosts a mid-altitude rainforest. The forest has long faced strong anthropogenic disturbances, such as slash-and-burn agriculture, logging, and poaching. Prior to this study, no long-term study on the lemur community in Vohimana had been conducted and no updated information was available. We aimed to provide a lemur inventory and a description of threats that could be used by forest managers in order to inform and optimize future conservation plans. Between April and December 2018, we surveyed the forest using line-transect distance sampling. Our results show that Vohimana is home to 11 lemur species, including two critically endangered species (Indri indri and Propithecus diadema). We found no evidence of the presence of the black-and-white ruffed lemur (Varecia variegata), which was once reported to inhabit the forest. The possible disappearance of this species, the low frequency of Lemuridae species observations, and the observation of snares, selective logging, and charcoal production suggest actions and long-term monitoring are urgently needed in order to protect this fragile but strategic ecosystem.
Habitat loss and poaching are among the most serious threats to the fragile and unique biodiversi... more Habitat loss and poaching are among the most serious threats to the fragile and unique biodiversity of Madagascar. In the past, traditional taboos (fady), commonly associated with folk stories, have had a buffering effect on several lemur species. Here, we examine the status of hunting taboos with reference to the conservation of the critically endangered Perrier's sifaka (Propithecus perrieri). We also provide an update on P. perrieri’s presence in the protected area of Andrafiamena in the face of ongoing habitat fragmentation and poaching. The Andrafiamena forest represents one of the key refuges for this species, which has a very limited and fragmented range in northern Madagascar. We report the results of a 2016 presence/absence survey in Andrafiamena and from interviews on Perrier’s sifaka taboo adherence, conducted in 2012 across the whole species range. Our results confirm the presence of Perrier’s sifakas in Andrafiamena and that in 2012, across the species’ range, the hunting taboo was observed by most (>95%) interviewees who answered (N = 23). Forest clearing and a decrease of taboo adherence may intensify the pressure on the already small and fragile population of P. perrieri. A deeper knowledge of the human-wildlife interconnections, as well as regular monitoring of this rare species’ distribution, may be crucial for the success of its conservation.
Tree hollows provide shelters for a large number of forest-de-
pendent vertebrate species worldwi... more Tree hollows provide shelters for a large number of forest-de- pendent vertebrate species worldwide. In Madagascar, where high historical and ongoing rates of deforestation and forest degrada- tion are responsible for a major environmental crisis, reduced availability of tree hollows may lead to declines in hollow-dwelling species such as sportive lemurs, one of the most species-rich groups of lemurs. The identification of native tree species used by hollow-dwelling lemurs may facilitate targeted management inter- ventions to maintain or improve habitat quality for these lemurs. During an extensive survey of sportive lemurs in northern Mada- gascar, we identified one tree species, Strychnos madagascarien- sis (Loganiaceae), the spineless monkey orange tree, as a principal sleeping site of two species of northern sportive lemurs, Lepile- mur ankaranensis and L. milanoii (Lepilemuridae). This tree spe- cies represented 32.5% (n=1 50) of the 458 sleeping sites recorded. This result suggests that S. madagascariensis may be valuable for the conservation of hollow-dwelling lemurs.
The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confin... more The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confined to the Loky-Manambato region . Very little is known about L. milanoii and it is classified as "Data Deficient" by the IUCN . Despite the management of the area by the NGO Fanamby since 2005, no study had been conducted to determine the presence and the abundance of L. milanoii in the main forest fragments of the region. During the 2011 dry season we surveyed the ten main forest fragments of the Loky-Manambato region and estimated L. milanoii densities and population sizes using line transect distance sampling and the DISTANCE software . The results suggest that sportive lemur densities are reasonably high in the region, but with important discrepancies between forest fragments, with densities ranging from 49.8 ind./km² in Antsaharaingy to 590.5 ind./km² in Ampondrabe. For the region Loky-Manambato we were able to estimate a population size of ~52,000 individuals. This is the first estimate for the total population size and we argue that similar studies should be repeated to monitor environmental changes and anthropogenic pressures (hunting, deforestation, mining, etc.).
Propithecus perrieri (Perrier's sifaka) is one of the most endangered lemur species due to its 27... more Propithecus perrieri (Perrier's sifaka) is one of the most endangered lemur species due to its 27 small and fragmented distribution range. Despite a critically endangered (CR) conservation 28 and flagship species status, there are still many uncertainties regarding its actual distribution 29 and its presence in some forests of its putative distribution range. We report the results of 30 diurnal and nocturnal surveys carried out in 2012 across most forest fragments of its putative 31 distribution range, namely the Ankarana National Park, the Analamerana Special Reserve and 32
Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats mon... more Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats montrent que les densités de microcèbes sont relativement élevées, et varient de 28 à 325 ind/km² entre fragments forestiers de la région. Des études plus approfondies des données collectées seront nécessaires pour déterminer les variables environnementales responsables des différences de densité observées.
Developing Coffea arabica seeds accumulate large amounts of chlorogenic acids (CGAs) as a storage... more Developing Coffea arabica seeds accumulate large amounts of chlorogenic acids (CGAs) as a storage form of phenylpropanoid derivatives, making coffee a valuable model to investigate the metabolism of these widespread plant phenolics. However, developmental and environmental regulations of CGA metabolism are poorly understood. In the present work, the expression of selected phenylpropanoid genes, together with CGA isomer profiles, was monitored throughout seed development across a wide set of contrasted natural environments. Although CGA metabolism was controlled by major developmental factors, the mean temperature during seed development had a direct impact on the time-window of CGA biosynthesis, as well as on final CGA isomer composition through subtle transcriptional regulations. We provide evidence that the variability induced by the environment is a useful tool to test whether CGA accumulation is quantitatively modulated at the transcriptional level, hence enabling detection of rate-limiting transcriptional steps [quantitative trait transcripts (QTTs)] for CGA biosynthesis. Variations induced by the environment also enabled a better description of the phenylpropanoid gene transcriptional network throughout seed development, as well as the detection of three temporally distinct modules of quantitatively co-expressed genes. Finally, analysis of metabolite-to-metabolite relationships revealed new biochemical characteristics of the isomerization steps that remain uncharacterized at the gene level.
The seed of Coffea arabica accumulates large amounts of cell wall storage polysaccharides (CWSPs)... more The seed of Coffea arabica accumulates large amounts of cell wall storage polysaccharides (CWSPs) of the mannan family in the cell walls of the endosperm. The variability induced by the growing environment and extensive pairwise correlation analysis with stringent significance thresholds was used to investigate transcript-transcript and transcript-metabolite relationships among 26 sugar-related genes, and the amount of CWSPs and seven soluble low molecular weight carbohydrates in the developing coffee endosperm. A dense module of nine quantitatively co-expressed genes was detected at the mid-developmental stage when CWSPs accumulate. This module included the five genes of the core galactomannan synthetic machinery, namely genes coding for the enzymes needed to assemble the mannan backbone (mannan synthase, ManS), and genes that introduce the galactosyl side chains (galactosyltransferase, GMGT), modulate the post-depositional degree of galactose substitution (α-galactosidase), and produce the nucleotide sugar building blocks GDP-mannose and UDP-galactose (mannose-1P guanyltransferase and UDP-glucose 4'-epimerase, respectively). The amount of CWSPs stored in the endosperm at the onset of their accumulation was primarily and quantitatively modulated at the transcriptional level (i.e. positively correlated with the expression level of these key galactomannan biosynthetic genes). This analysis also suggests a role for sorbitol and raffinose family oligosaccharides as transient auxiliary sources of building blocks for galactomannan synthesis. Finally, a microarray-based analysis of the developing seed transcriptome revealed that all genes of the core galactomannan synthesis machinery grouped in a single cluster of 209 co-expressed genes. Analysis of the gene composition of this cluster revealed remarkable functional coherence and identified transcription factors that putatively control galactomannan biosynthesis in coffee.
The crowned sifaka (Propithecus coronatus) is Endangered. It has a large but highly fragmented di... more The crowned sifaka (Propithecus coronatus) is Endangered. It has a large but highly fragmented distribution; its known range extends from the Betsiboka River in the north of Madagascar, to the Mahavavy River in the north-west, and down to the Tsiribihina River in the south-west. The species lives in forest habitats that are highly and increasingly fragmented and are continuously suffering perturbations and destruction. In order to carry out effective conservation measures targeting P. coronatus, its conservation status needs to be updated so that measures can be taken before anthropogenic or natural environmental changes lead to the extirpation of the species in most of its forests. We (i) identified forest fragments where the species is still present and (ii) using the line-transect "Distance" sampling method, estimated the population size and density in the principal remaining forest fragments in the northern part of its range, including both protected and unprotected areas. We visited most of the forests in the northern part of its range in order to update the current area of occupancy, and to rate the state of its forests using a qualitative "forest quality index." Our survey results have shown that (i) a large number of forests have disappeared or decreased in size in the last 10 years, and (ii) population densities vary considerably among forest fragments (ranging from 49 to 309 individuals per km²), with some very high densities in forests located along the Mahavavy River and in the Antrema area. Their abundance in the area surveyed is likely to be between 4,226 and 36,672 individuals, and most probably above 10,000. It is difficult to extrapolate from these estimates to the total abundance across the species' entire range, but we estimate that it is likely to be large, probably between 130,000 and 220,000 individuals. Unfortunately, many field observations suggest that its populations continue to decline at a high rate due to habitat loss and hunting, and we argue for the re-evaluation of the conservation status from Endangered A2cd to Endangered A4acd, and the need to survey the rest of the range of P. coronatus.
Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite i... more Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite its Endangered (EN) IUCN conservation status, uncertainties persist regarding its actual distribution and its presence in forests that are thought to be part of its distribution range. We provide here the first extensive population surveys of Coquerel's sifaka across a large number of forest fragments neighboring 27 sites of its known and expected distribution range in northwestern Madagascar, including 12 previously visited sites. During our diurnal surveys carried out in the dry seasons from 2009 to 2011 we observed the species in 26 of the 27 visited sites. Combining our results with previously published data, we propose a refined update of the species' distribution range and identify areas to be surveyed. We also recorded the support tree species on which sifakas were observed, and note that, surprisingly, P. coquereli was frequently seen around villages and in areas dominated by introduced tree species. Although the species was present at almost all the visited sites of its highly fragmented distribution range, it remains unclear how viable the populations of a significant proportion of these sites actually are. Due to political instability and high rates of deforestation, large-scale conservation actions are urgently needed. We thus (1) discuss the outline of a possible metapopulation conservation action plan for P. coquereli and (2) identify priority sites and actions.
Rajaonson, A.; Ratolojanahary, T.; Rafalimandimby, J.; Fanomezantsoa, P.; Ramahefasoa, B.; Rasolo... more Rajaonson, A.; Ratolojanahary, T.; Rafalimandimby, J.; Fanomezantsoa, P.; Ramahefasoa, B.; Rasolofoharivelo, T.; Ravaloharimanitra, M.; Ratsimbazafy, J.; Dolch, R.; King, T. 2011. New distributional records and conservation implications for the critically endangered greater bamboo lemur Prolemur simus. Folia Primatologica 82 (2): 118-129. Randrianarimanana, L.; Ravaloharimanitra, M.; Ratolojanahary, T.; Rafalimandimby, J.; Rasolofoharivelo, T.; Ratsimbazafy, J.; Dolch, R.; King, T. 2012. Statut et conservation de Prolemur simus dans les sites de Ranomainty et Sakalava du Corridor Ankeniheny-Zahamena. Lemur News 16: 2-7. Ravaloharimanitra, M.; Ratolojanahary, T.; Rafalimandimby, J.; Rajaonson, A.; Rakotonirina, L.; Rasolofoharivelo, T.; Ndriamiary, J.N.; Andriambololona, J.; Nasoavina, C.; Fanomezantsoa, P.; Rakotoarisoa, J.C.; Youssouf; Ratsimbazafy, J.; Dolch, R.; King, T. 2011. Gathering local knowledge in Madagascar results in a major increase in the known range and number of sites for critically endangered greater bamboo lemurs (Prolemur simus).
Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats mon... more Dans ce but nous avons utilisé la méthode de «line transect distance-sampling». Nos résultats montrent que les densités de microcèbes sont relativement élevées, et varient de 28 à 325 ind/km² entre fragments forestiers de la région. Des études plus approfondies des données collectées seront nécessaires pour déterminer les variables environnementales responsables des différences de densité observées.
The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confin... more The population of the Daraina sportive lemur (Lepilemur milanoii) is believed to be mostly confined to the Loky-Manambato region . Very little is known about L. milanoii and it is classified as "Data Deficient" by the IUCN . Despite the management of the area by the NGO Fanamby since 2005, no study had been conducted to determine the presence and the abundance of L. milanoii in the main forest fragments of the region. During the 2011 dry season we surveyed the ten main forest fragments of the Loky-Manambato region and estimated L. milanoii densities and population sizes using line transect distance sampling and the DISTANCE software . The results suggest that sportive lemur densities are reasonably high in the region, but with important discrepancies between forest fragments, with densities ranging from 49.8 ind./km² in Antsaharaingy to 590.5 ind./km² in Ampondrabe. For the region Loky-Manambato we were able to estimate a population size of ~52,000 individuals. This is the first estimate for the total population size and we argue that similar studies should be repeated to monitor environmental changes and anthropogenic pressures (hunting, deforestation, mining, etc.).
Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite i... more Coquerel's sifaka Propithecus coquereli has a large but highly fragmented distribution. Despite its Endangered (EN) IUCN conservation status, uncertainties persist regarding its actual distribution and its presence in forests that are thought to be part of its distribution range. We provide here the first extensive population surveys of Coquerel's sifaka across a large number of forest fragments neighboring 27 sites of its known and expected distribution range in northwestern Madagascar, including 12 previously visited sites. During our diurnal surveys carried out in the dry seasons from 2009 to 2011 we observed the species in 26 of the 27 visited sites. Combining our results with previously published data, we propose a refined update of the species' distribution range and identify areas to be surveyed. We also recorded the support tree species on which sifakas were observed, and note that, surprisingly, P. coquereli was frequently seen around villages and in areas dominated by introduced tree species. Although the species was present at almost all the visited sites of its highly fragmented distribution range, it remains unclear how viable the populations of a significant proportion of these sites actually are. Due to political instability and high rates of deforestation, large-scale conservation actions are urgently needed. We thus (1) discuss the outline of a possible metapopulation conservation action plan for P. coquereli and (2) identify priority sites and actions.
The global loss of biodiversity continues at an alarming rate. Genomic approaches have been sugge... more The global loss of biodiversity continues at an alarming rate. Genomic approaches have been suggested as a promising tool for conservation practice as scaling up to genome-wide data can improve traditional conservation genetic inferences and provide qualitatively novel insights. However, the generation of genomic data and subsequent analyses and interpretations remain challenging and largely confined to academic research in ecology and evolution. This generates a gap between basic research and applicable solutions for conservation managers faced with multifaceted problems. Before the real-world conservation potential of genomic research can be realized, we suggest that current infrastructures need to be modified, methods must mature, analytical pipelines need to be developed, and successful case studies must be disseminated to practitioners.
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Papers by Jordi Salmona
pendent vertebrate species worldwide. In Madagascar, where high
historical and ongoing rates of deforestation and forest degrada-
tion are responsible for a major environmental crisis, reduced
availability of tree hollows may lead to declines in hollow-dwelling
species such as sportive lemurs, one of the most species-rich
groups of lemurs. The identification of native tree species used by
hollow-dwelling lemurs may facilitate targeted management inter-
ventions to maintain or improve habitat quality for these lemurs.
During an extensive survey of sportive lemurs in northern Mada-
gascar, we identified one tree species, Strychnos madagascarien-
sis (Loganiaceae), the spineless monkey orange tree, as a principal
sleeping site of two species of northern sportive lemurs, Lepile-
mur ankaranensis and L. milanoii (Lepilemuridae). This tree spe-
cies represented 32.5% (n=1 50) of the 458 sleeping sites recorded.
This result suggests that S. madagascariensis may be valuable for
the conservation of hollow-dwelling lemurs.
pendent vertebrate species worldwide. In Madagascar, where high
historical and ongoing rates of deforestation and forest degrada-
tion are responsible for a major environmental crisis, reduced
availability of tree hollows may lead to declines in hollow-dwelling
species such as sportive lemurs, one of the most species-rich
groups of lemurs. The identification of native tree species used by
hollow-dwelling lemurs may facilitate targeted management inter-
ventions to maintain or improve habitat quality for these lemurs.
During an extensive survey of sportive lemurs in northern Mada-
gascar, we identified one tree species, Strychnos madagascarien-
sis (Loganiaceae), the spineless monkey orange tree, as a principal
sleeping site of two species of northern sportive lemurs, Lepile-
mur ankaranensis and L. milanoii (Lepilemuridae). This tree spe-
cies represented 32.5% (n=1 50) of the 458 sleeping sites recorded.
This result suggests that S. madagascariensis may be valuable for
the conservation of hollow-dwelling lemurs.