Mahajanga, Madagascar

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Fischer E.,University of Koblenz-Landau | Rahelivololona M.E.,University of Mahajanga | Abrahamczyk S.,University of Bonn
Phytotaxa | Year: 2017

Impatiens galactica, a new species from lowland rainforest in Marojejy National Park, NE Madagascar, is described and illustrated. It belongs to Impatiens section Trimorphopetalum and is related to I. messmerae, also known from Mt. Marojejy. Impatiens galactica differs from the latter species in the shape of the lateral sepals, and in the dorsal petal and the lateral united petals being entirely glabrous and lacking small white scales. Furthermore, I. galactica has a distinct flower morphology with strongly reduced upper lobes of the lateral united petals. The lateral petals are thus resembling the lower case letter “b” or “d”, respectively. Additionally, it has unusually coloured yellowish white, semi-transparent flowers with an orange-yellow, shiny line along the midrib of the lower sepal, all of which are lacking in I. messmerae. © 2017 Magnolia Press.


Schwitzer C.,Bristol Zoological Society | Mittermeier R.A.,Wildlife Conservation Society | Johnson S.E.,University of Calgary | Donati G.,Oxford Brookes University | And 17 more authors.
Science | Year: 2014

Community-based management, ecotourism, and researchers' presence are proposed to prevent lemur extinctions.


Rumpler Y.,University of Strasbourg | Hauwy M.,University of Strasbourg | Fausser J.-L.,University of Strasbourg | Roos C.,Gene Bank of Primates and Primate Genetics Laboratory | And 3 more authors.
Chromosome Research | Year: 2011

The Malagasy primate family Indriidae comprises three genera with up to 19 species. Cytogenetic and molecular phylogenies of the Indriidae have been performed with special attention to the genus Propithecus. Comparative R-banding and FISH with human paints were applied to karyotypes of representatives of all three genera and confirmed most of the earlier R-banding results. However, additional chromosomal rearrangements were detected. A reticulated and a cladistic phylogeny, the latter including hemiplasies, have been performed. Cladistic analysis of cytogenetic data resulted in a phylogenetic tree revealing (1) monophyly of the family Indriidae, (2) monophyly of the genus Avahi, (3) sister-group relationships between Propithecus diadema and Propithecus edwardsi, and (4) the grouping of the latter with Indri indri, Propithecus verreauxi, and Propithecus tattersalli, and thus suggesting paraphyly of the genus Propithecus. A molecular phylogeny based on complete mitochondrial cytochrome b sequences of 16 species indicated some identical relationships, such as the monophyly of Avahi and the sister-group relationships of the eastern (P. diadema and P. edwardsi) to the western Propithecus species (P. verreauxi, Propithecus coquereli, and P. tattersalli). However, the main difference between the molecular and cytogenetic phylogenies consists in an early divergence of Indri in the molecular phylogeny while in the chromosomal phylogeny it is nested within Propithecus. The similarities and differences between molecular and cytogenetic phylogenies in relation to data on the species' geographic distributions and mating systems allow us to propose a scenario of the evolution of Indriidae. Chromosomal and molecular processes alone or in combination created a reproductive barrier that was then followed by further speciation processes. © 2011 Springer Science+Business Media B.V.


Giacoma C.,University of Turin | Sorrentino V.,University of Turin | Rabarivola C.,University of Mahajanga | Gamba M.,University of Turin
International Journal of Primatology | Year: 2010

In some primate species, males and females within a social group emit loud calls in a coordinated manner or chorus. Indri indri emits a very conspicuous loud call that elicits the loud calls of neighboring groups. Previous investigations have hypothesized that the main functions of the indri chorus are related to territorial announcement, intergroup avoidance, and group cohesion. We investigated sex differences in indri song. We recorded and analysed songs given by 10 different groups over 160 d. Overall singing duration did not vary between the sexes. However, males emitted significantly fewer but longer notes. Adult males and females of each group participated in the song with sex-specific repertoires. Females had a song repertoire of 8 note types; males shared all of their 6 notes with females. Apart from the initial roars, in all note types shared by both sexes, male notes were significantly longer than female ones, whereas variations in frequency parameters differed according to the note type. These findings suggest that indri song may provide cues to conspecifics, such as group size and sex composition, which could influence interactions between groups. © 2010 Springer Science+Business Media, LLC.


Rasoloharijaona S.,University of Mahajanga | Randrianambinina B.,University of Mahajanga | Joly-Radko M.,University of Mahajanga | Joly-Radko M.,University of Veterinary Medicine Hannover
American Journal of Primatology | Year: 2010

Nonhuman primates may defend crucial resources using acoustic or chemical signals. When essential resources are limited, ownership display for a resource may be enhanced. Defending resources may depend on population density and habitat characteristics. Using the Milne Edwards' sportive lemurs (Lepilemur edwardsi) and weasel sportive lemurs (L. mustelinus) as models, we tested whether two cryptic nocturnal lemur species differing in population density and habitat show differences in their vocal and chemical communication for signaling ownership of resources. L. edwardsi inhabits a western dry deciduous forest in a high-density population, whereas L. mustelinus is found in an eastern rainforest in low density. We followed ten L. edwardsi (six males and four females) and nine L. mustelinus (four males and five females) for 215 hr during the early evening (06:00-10:00 p.m.) and the early morning (02:00-05:00 a.m.) and recorded their behavior using focal animal sampling. We found that both species differed in their vocal and chemical communication. L. edwardsi was highly vocal and displayed loud calling in the mornings and evenings while feeding or in the vicinity of resting places. In contrast, L. mustelinus never vocalized during observations, but displayed tree-gouging behavior that was never observed in L. edwardsi. Tree gouging occurred more often during early evening sessions than early morning sessions. Subjects gouged trees after leaving their sleeping hole and before moving around. We suggest that, in weasel sportive lemurs, non-nutritive tree gouging is used as a scent-marking behavior in order to display ownership of sleeping sites. Altogether, our findings provide first empirical evidence on the evolution of different communication systems in two cryptic nocturnal primate species contrasting in habitat quality and population density. Further investigations are needed to provide more insight into the underlying mechanisms. Am. J. Primatol. 72:1062-1072, 2010. © 2010 Wiley-Liss, Inc.


Quemere E.,French National Center for Scientific Research | Quemere E.,CNRS Biological Evolution and Diversity Laboratory | Crouau-Roy B.,French National Center for Scientific Research | Crouau-Roy B.,CNRS Biological Evolution and Diversity Laboratory | And 4 more authors.
Molecular Ecology | Year: 2010

Habitat fragmentation may strongly reduce individuals' dispersal among resource patches and hence influence population distribution and persistence. We studied the impact of landscape heterogeneity on the dispersal of the golden-crowned sifaka (Propithecus tattersalli), an endangered social lemur species living in a restricted and highly fragmented landscape. We combined spatial analysis and population genetics methods to describe population units and identify the environmental factors which best predict the rates and patterns of genetic differentiation within and between populations. We used non-invasive methods to genotype 230 individuals at 13 microsatellites in all the main forest fragments of its entire distribution area. Our analyses suggest that the Manankolana River and geographical distance are the primary structuring factors, while a national road crossing the region does not seem to impede gene flow. Altogether, our results are in agreement with a limited influence of forest habitat connectivity on gene flow patterns (except for North of the species' range), suggesting that dispersal is still possible today among most forest patches for this species. Within forest patches, we find that dispersal is mainly among neighbouring social groups, hence confirming previous behavioural observations. © 2010 Blackwell Publishing Ltd.


Honda A.,University of Cape Town | Randaoharison P.G.,University of Mahajanga | Matsui M.,Maternal and Child Health Group
Reproductive Health Matters | Year: 2011

Timely access to emergency obstetric care is necessary to save the lives of women experiencing complications at delivery, and for newborn babies. Out-of-pocket costs are one of the critical factors hindering access to such services in low- and middle-income countries. This study measured out-of-pocket costs for caesarean section and neonatal care at an urban tertiary public hospital in Madagascar, assessed affordability in relation to household expenditure and investigated where families found the money to cover these costs. Data were collected for 103 women and 73 newborns at the Centre Hospitalier Universitaire de Mahajanga in the Boeny region of Madagascar between September 2007 and January 2008. Out-of-pocket costs for caesarean section were catastrophic for middle and lower socio-economic households, and treatment for neonatal complications also created a big financial burden, with geographical and other financial barriers further limiting access to hospital care. This study identified 12 possible cases where the mother required an emergency caesarean section and her newborn required emergency care, placing a double burden on the household. In an effort to make emergency obstetric and neonatal care affordable and available to all, including those living in rural areas and those of medium and lower socio-economic status, well-designed financial risk protection mechanisms and a strong commitment by the government to mobilise resources to finance the country's health system are necessary. © 2011 Reproductive Health Matters.


Aymoz B.G.P.,Laval University | Randrianjafy V.R.,University of Mahajanga | Randrianjafy Z.J.N.,Direction Provincial du Projet de Soutien Au Developpement Rural | Khasa D.P.,Laval University
Ambio | Year: 2013

We analyzed the management, resource use and conservation of the Ankarafantsika National Park (Madagascar) to develop a management plan, which provides a sustainable development strategy of the area while empowering the local residents. Using qualitative methodology we performed interviews with villagers and local organizations to assess the park's successes and failures from local stakeholders' perspectives. People living in a village with a permanent Madagascar National Parks (MNP) agent are more favorable to and supportive of the park conservation. People living in the park are supportive but are more divided. On the other hand, people living on the periphery of the park see conservation as more of a burden. Strategies like more equitable distribution of wealth, environment improvement and decentralization of power are discussed to achieve a more sustainable management plan based on community natural resources management. Short-term, medium, and long-term interventions from park authorities are needed to ensure the cooperation of local people in conservation endeavors. © 2013 Royal Swedish Academy of Sciences.


Fischer E.,University of Koblenz-Landau | Rahelivololona M.E.,University of Mahajanga
Phytotaxa | Year: 2015

Two new species, Impatiens susan-nathansoniae and I. hendrikii, from Mt. Marojejy, Madagascar, are described. Impatiens susan-nathansoniae is related to I. humblotiana from eastern central Madagascar, but differs in the shape of the lower sepal with spur, the dorsal petal and the lateral united petals. Impatiens hendrikii is related to I. fuchsioides, but differs in the straight stem, the larger leaves, the broader lateral sepals, the broader lateral united petals with different shape, and the glabrous lower sepal gradually tapering into a short, saccate, whitish red spur. © 2015 Magnolia Press.


The available data on the prevalence of tobacco use among teenagers in Madagascar are very limited. The aim of this study was to analyze tobacco-use behaviors among teenage pupils aged 12 to 18 living in urban and suburban areas of Madagascar and to identify the associated risk factors. A cross-sectional descriptive study was conducted as part of this research. Probabilistic multistage sampling was used to obtain a representative sample. Data were collected using an anonymous self-reported questionnaire and computer analyzed using SPSS 16. Correlation and logistic regression were used to analyze the risk factors. The results show that approximately one third of the 711 pupils (36.3%) included in the sample reported that they had tried tobacco. Among them, 25.2% were regular users. Nearly 10% had started smoking before the age of 14. Male adolescents were found to smoke twice as much as their female counterparts. The study found that the key factors associated with tobacco use include: male gender (Exp(B)=3,769(95%IC 2,579-5,509), urbanization (Exp(B) = 3,679, 95% IC 2,138-6,332), age, peer influence, a sense of insecurity at school, and the impact of the mass media (films, television). The study found that the family environment did not have a significant impact on tobacco use. To conclude, the prevalence of smoking among teenage pupils in Madagascar is a significant issue. This paper argues that it is important to understand the associated risk factors in order to develop a prevention program aimed at reversing the tobacco epidemic in schools. © S.F.S.P.. Tous droits réservés pour tous pays.

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