68 research outputs found
The Alaotra gentle lemur: Population estimation and subsequent implications
Durrell Wildlife Conservation Trust (DWCT) has conducted since 1994 several census’ on the population of the Alaotran gentle lemur to observe the development of the population in time and space
Local socio-economic effects of protected area conservation: The case of Maromizaha forest, Madagascar
The vision Madagascar Naturally aimed to triple the size of protected areas in Madagascar from 1.7 million hectares to 6 million hectares before 2008, in order to ensure the safe guarding of Madagascar’s natural heritage and the human well-being that depends on it. In 2008, Maromizaha forest was selected by the Ministry of Environment and Forests tobecome a New Protected Area where the delegated manager is the Groupe d’Etude et de Recherche sur les Primates de Madagascar (GERP). One of GERP’s strategies is to provide support to the livelihoods of the local people around the Maromizaha protected area in order to reduce the dependency on natural resources. During April 2014, GERP organized a rapid socio-economic survey of 70 households across six villages, in order to make a preliminary, comparison and assessment of this development support and its impact on the main income generating activities of the local people, their highest level of formal education in 2008 and 2014, and their thinking about conservation offsetting. The results showed that in 2014, 70% of local people were engaged in agriculture and less than 40% in cattle farming. Some villagers have benefited from pilot development projects organized by financial and environmental organizations. Other local people benefited from other livelihood activities related to the conservation management of the forest. Most participants were aware of the ecosystem services of the forests (94.3%) and the education level has increased from 2008 to 2014, although even in 2014, 56% of the survey participants were educated only to primary school level; the rate of illiteracy is at 15.6%. We summarize some strengths, weaknesses and recommendations in order to improve the management of the Maromizaha Protected Area
Behavior and diet of the Critically Endangered Eulemur cinereiceps in Manombo forest, southeast Madagascar
Manombo Special Reserve is a parcel of rainforest along the southeastern coast of Madagascar, containing eight lemur species, including the White-collared brown lemur (Eulemur cinereiceps [Eulemur albocollaris]). Following a drastic cyclone in the region in January of 1997, the population of E. cinereiceps at Manombo was reduced by half. Results indicate that individuals of this critically endangered species at Manombo consume a total of 54 plant species belonging to 24 families, with over two-thirds of the diet comprised of ripe and unripe fruits. White-collared brown lemurs also opportunistically feed on novel food items and invasive plants in their recovering habitat. We report the first record of E. cinereiceps consuming a shelf fungus species growing on invasive trees. During feeding, lemurs tore pieces of the fungus from the trees with their hands and mouth (chewing cycle duration mean 0.28 s; SD 0.01). White-collared brown lemurs also consumed spicy fruits of a non-native plant species (Aframomum angustifolium) growing in highly disturbed open areas. Feeding bouts typically began by stripping away the outer covering with the anterior dentition, with pulp and seeds then consumed (chewing cycle duration mean 0.22 s; SD 0.005). This is the first record of consumption of either of these resources for any lemur species at Manombo. Ability to feed on items like A. angustifolium may permit E. cinereiceps to avoid competition with other species in this highly degraded forest environment.RÉSUMÉ La Réserve Spéciale de Manombo est un fragment de forêt dense humide de basse altitude et située le long de la côte Sud-est de Madagascar. Cette partie de forêt abrite au total huit espèces de lémuriens, y compris le Lémur à collier blanc (Eulemur cinereiceps [Eulemur albocollaris]). Le passage dramatique du cyclone Gretelle dans la région en janvier 1997 a réduit de moitié la taille de la population d’E. cinereiceps dans sa zone de distribution. Les résultats des études effectuées sur les individus restants de cette espèce, qui est classée comme Gravement Menacée, permettent d’énumérer un total de 54 espèces de plantes appartenant à 24 familles qui sont consommées par l’espèce. D’autre part, deux tiers du régime alimentaire d’E. cinereiceps sont représentés par des fruits mûrs ou non. Le Lémur à collier blanc consomme occasionnellement une quantité assez importante de plantes envahissantes pour assurer ses besoins nutritifs, ce qui n’est pas habituel dans l’histoire naturelle de la vie des lémuriens. La présente étude constitue également la première observation de consommation d’une espèce inconnue de champignon par les représentants d’E. cinereiceps. Dans le présent cas, ledit champignon venait juste de pousser sur un pied mort de Cecropia peltata, une espèce allogène et envahissante de la région. Durant la prise de nourriture, l’animal a arraché des morceaux du champignon sur l’arbre mort avec la main et puis la bouche. La partie consommée a été mâchée par l’animal pendant une période de 0,28 s. Le Lémur à collier blanc consomme aussi des fruits épicés d’une espèce de plante allogène (Aframomum angustifolium) qui ne pousse que dans des zones ouvertes et extrêmement dégradées. La prise de nourriture sur cette espèce de plante commence par l’enlèvement de la partie dure du fruit, pour cela l’animal utilise ses dents antérieures très puissantes, puis il tire soigneusement en même temps avec ses dents et sa langue la partie charnue et les graines. Cette prise de nourriture s’effectue pendant une période d’environ 0,22 s. C’était la première fois dans l’histoire des lémuriens de Manombo que des observations ont été effectuées sur un animal en train de manger des espèces de plantes inhabituelles. L’aptitude de manger des espèces de plantes telle que A. angustifolium pourrait permettre à E. cinereiceps d’éviter la compétition avec les autres espèces de lémuriens vivant dans cet environnement dégradé
Luminous Red Galaxies in Simulations: Cosmic Chronometers?
There have been a number of attempts to measure the expansion rate of the
universe at high redshift using Luminous Red Galaxies (LRGs) as "chronometers".
The method generally assumes that stars in LRGs are all formed at the same
time. In this paper, we quantify the uncertainties on the measurement of H(z)
which arise when one considers more realistic, extended star formation
histories. In selecting galaxies from the Millennium Simulation for this study,
we show that using rest-frame criteria significantly improves the homogeneity
of the sample and that H(z) can be recovered to within 3% at z~0.42 even when
extended star formation histories are considered. We demonstrate explicitly
that using Single Stellar Populations to age-date galaxies from the
semi-analytical simulations provides insufficient accuracy for this experiment
but accurate ages are obtainable if the complex star formation histories
extracted from the simulation are used. We note, however, that problems with
SSP-fitting might be overestimated since the semi-analytical models tend to
over predict the late-time star-formation in LRGs. Finally, we optimize an
observational program to carry out this experiment.Comment: 11 pages, 10 figures. Accepted to MNRAS
Primates in peril: the significance of Brazil, Madagascar, Indonesia and the Democratic Republic of the Congo for global primate conservation
Primates occur in 90 countries, but four—Brazil, Madagascar, Indonesia, and the Democratic Republic of the Congo (DRC)—harbor 65% of the world’s primate species (439) and 60% of these primates are Vulnerable, Endangered, or Critically Endangered (IUCN Red List of Threatened Species 2017-3). Considering their importance for global primate conservation, we examine the anthropogenic pressures each country is facing that place their primate populations at risk. Habitat loss and fragmentation are main threats to primates in Brazil, Madagascar and Indonesia. However, in DRC hunting for the commercial bushmeat trade is the primary threat. Encroachment on primate habitats driven by local and global market demands for food and non-food commodities hunting, illegal trade, the proliferation of invasive species, and human and domestic-animal borne infectious diseases cause habitat loss, population declines, and extirpation. Modeling agricultural expansion in the 21st century for the four countries under a worst-case-scenario, showed a primate range contraction of 78% for Brazil, 72% for Indonesia 62% for Madagascar and 32% for DRC. These pressures unfold in the context of expanding human populations with low levels of development. Weak governance across these four countries may limit effective primate conservation planning. We examine landscape and local approaches to effective primate conservation policies and assess the distribution of protected areas and primates in each country. P rimates in Brazil and Madagascar have 38% of their range inside protected areas, 17% in Indonesia and 14% in DRC, suggesting that the great majority of primate populations remain vulnerable. We list the key challenges faced by the four countries to avert primate extinctions now and in the future. In the short term, effective law enforcement to stop illegal hunting and illegal forest destruction is absolutely key. Long-term success can only be achieved by focusing local and global public awareness, actively engaging with international organizations, multinational businesses and consumer nations to reduce unsustainable demands on the environment. Finally, the four primate range states need to ensure that integrated, sustainable land-use planning for economic development includes the maintenance of biodiversity and intact, functional natural ecosystems
A Severe Lack of Evidence Limits Effective Conservation of the World's Primates
Threats to biodiversity are well documented. However, to effectively conserve species and their habitats, we need to know which conservation interventions do (or do not) work. Evidence-based conservation evaluates interventions within a scientific framework. The Conservation Evidence project has summarized thousands of studies testing conservation interventions and compiled these as synopses for various habitats and taxa. In the present article, we analyzed the interventions assessed in the primate synopsis and compared these with other taxa. We found that despite intensive efforts to study primates and the extensive threats they face, less than 1% of primate studies evaluated conservation effectiveness. The studies often lacked quantitative data, failed to undertake postimplementation monitoring of populations or individuals, or implemented several interventions at once. Furthermore, the studies were biased toward specific taxa, geographic regions, and interventions. We describe barriers for testing primate conservation interventions and propose actions to improve the conservation evidence base to protect this endangered and globally important taxon
Reconciling nature, people and policy in the mangrove social-ecological system through the adaptive cycle heuristic
© 2021 The Authors. While mangroves are increasingly described as social-ecological systems (SESs), performing SES research is so much more than merely documenting local resource utilisation patterns in case studies. The aim of this paper is to review and show how ecological, human and institutional resilience could be understood and fostered in an era of uncertainty, through the adaptive cycle (AC) heuristic. Uncertainties come in many forms and shapes: climate change, social and economic dynamics, natural disasters, political and institutional disruption and ever-increasing public demands for participation. Social-ecological studies form windows of experimentation that can provide insights beyond their case-specific context. In order to synthesise and structure the cumulative knowledge base arising from existing and future studies, the need for a suitable overarching framework arose. Here, the AC heuristic represents the connectedness between variables of the mangrove SES versus the mangrove's accumulated capital (natural, built, human and social). We posit that the AC heuristic can be used to interpret spatial and temporal changes (ecological, social, economic, political) in mangrove SESs and we exemplify it by using the 2004 Indian Ocean tsunami as well as a century-long silviculture case. The AC, combined with the SES scheme, allows integration of the spato-temporal dynamics and the multi-dimensional character of mangrove SESs. We also reviewed the ecosystem functions, services and disservices of mangrove SESs, linking each of them to SES capital and variable (fast or slow) attributes, which in turn are closely linked to the different axes and phases of the AC. We call upon mangrove scientists from the natural, applied, social and human sciences to join forces in fitting diversified empirical data from multiple case studies around the world to the AC heuristic. The aim is to reflect on and understand such complex dynamic systems with stakeholders having various (mutual) relationships at risk of breaking down, and to prepare for interactive adaptive planning for mangrove forests.Belgian Science Policy Office ‘EVAMAB – Economic valuation of ecosystem services in Man & Biosphere Reserves' - BELSPO (BL/58/UN32); Erasmus Mundus Masters Course in Tropical Biodiversity and Ecosystems (TROPIMUNDO); VLIR-UOS-funded GREENDYKE Project (ZEIN2008PR347); BELSPO-funded MAMAFOREST-Project (SR/00/323); ZMT Academy travel grant; Singapore National Parks Board (NParks); TUYF Charitable Trust; HKU Seed Fund for Research; International Coral Reef Initiative (ICRI); UNEP/GEF Blue Forest Project; Pew Charitable Trust; Department of Science and Technology, India INSPIRE Faculty scheme (IFA18-LSPA111)
Better Few than Hungry: Flexible Feeding Ecology of Collared Lemurs Eulemur collaris in Littoral Forest Fragments
Frugivorous primates are known to encounter many problems to cope with habitat degradation, due to the fluctuating spatial and temporal distribution of their food resources. Since lemur communities evolved strategies to deal with periods of food scarcity, these primates are expected to be naturally adapted to fluctuating ecological conditions and to tolerate a certain degree of habitat changes. However, behavioral and ecological strategies adopted by frugivorous lemurs to survive in secondary habitats have been little investigated. Here, we compared the behavioral ecology of collared lemurs (Eulemur collaris) in a degraded fragment of littoral forest of south-east Madagascar, Mandena, with that of their conspecifics in a more intact habitat, Sainte Luce.Lemur groups in Mandena and in Sainte Luce were censused in 2004/2007 and in 2000, respectively. Data were collected via instantaneous sampling on five lemur groups totaling 1,698 observation hours. The Shannon index was used to determine dietary diversity and nutritional analyses were conducted to assess food quality. All feeding trees were identified and measured, and ranging areas determined via the minimum convex polygon. In the degraded area lemurs were able to modify several aspects of their feeding strategies by decreasing group size and by increasing feeding time, ranging areas, and number of feeding trees. The above strategies were apparently able to counteract a clear reduction in both food quality and size of feeding trees.Our findings indicate that collared lemurs in littoral forest fragments modified their behavior to cope with the pressures of fluctuating resource availability. The observed flexibility is likely to be an adaptation to Malagasy rainforests, which are known to undergo periods of fruit scarcity and low productivity. These results should be carefully considered when relocating lemurs or when selecting suitable areas for their conservation
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