Center ValBio

Ranomafana, Madagascar

Center ValBio

Ranomafana, Madagascar
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Razafindratsima O.H.,Rice University | Razafindratsima O.H.,Center ValBio | Dunham A.E.,Rice University | Dunham A.E.,Center ValBio
Journal of Ecology | Year: 2016

Co-fruiting plant species are subject to a variety of biotic and abiotic processes that may influence patterns of fruiting phenology and the functional and phylogenetic diversity of co-fruiting taxa in a community. Understanding the seasonal patterns of functional and phylogenetic diversity of fruiting in a community will shed new light on potential mechanisms structuring plant communities. Using rain forest trees in south-eastern Madagascar as our system, we predicted there would be clustering of fruit and seed traits and phylogenetic relationships among co-fruiting species because plants are vying for seed-dispersal services from a limited set of generalist frugivore taxa. We also predicted that seasonal variations in rainfall would mediate fluctuations in functional trait and phylogenetic diversity of co-fruiting assemblages. Despite fluctuating patterns in their functional trait diversity over time, co-fruiting assemblages displayed consistent clustering of fruit/seed traits across time. Phylogenetic diversity was not clustered overall, but fluctuated non-randomly in time, between clustered and overdispersed, such that strong shifts in rainfall were associated with the co-fruiting of more closely related species. Synthesis. We suggest that it may be more beneficial for co-fruiting plant species to share similar fruit and seed traits than to diversify traits, when they rely on a comparatively small set of generalist frugivorous taxa for seed dispersal. Results also demonstrate that rainfall-driven environmental filtering may cause seasonal fluctuations in the phylogenetic patterns of phenology in a community. Results highlight the importance of a temporal context in examining structural patterns of communities. © 2016 The Authors. Journal of Ecology © 2016 British Ecological Society

Razafindratsima O.H.,Rice University | Razafindratsima O.H.,Center ValBio | Dunham A.E.,Rice University | Dunham A.E.,Center ValBio
Ecology | Year: 2015

Directed dispersal is defined as enhanced dispersal of seeds into suitable microhabitats, resulting in higher recruitment than if seeds were dispersed randomly. While this constitutes one of the main explanations for the adaptive value of frugivore-mediated seed dispersal, the generality of this advantage has received little study, particularly when multiple dispersers are involved. We used probability recruitment models of a long-lived rainforest tree in Madagascar to compare recruitment success under dispersal by multiple frugivores, no dispersal, and random dispersal. Models were parameterized using a three-year recruitment experiment and observational data of dispersal events by three frugivorous lemur species that commonly disperse its seeds. Frugivore-mediated seed dispersal was nonrandom with respect to canopy cover and increased modeled per-seed sapling recruitment fourfold compared to no dispersal. Seeds dispersed by one frugivore, Eulemur rubriventer, had higher modeled recruitment probability than seeds dispersed randomly. However, as a group, our models suggest that seeds dispersed by lemurs would have lower recruitment than if dispersal were random. Results demonstrate the importance of evaluating the contribution of multiple frugivores to plant recruitment for understanding plant population dynamics and the ecological and evolutionary significance of seed dispersal. © 2015 by the Ecological Society of America.

Razafindratsima O.H.,Rice University | Razafindratsima O.H.,Center ValBio | Dunham A.E.,Rice University | Dunham A.E.,Center ValBio
Ecology | Year: 2016

Frugivores are the main seed dispersers in many ecosystems, such that behaviorally driven, nonrandom patterns of seed dispersal are a common process; but patterns are poorly understood. Characterizing these patterns may be essential for understanding spatial organization of fruiting trees and drivers of seed-dispersal limitation in biodiverse forests. To address this, we studied resulting spatial associations between dispersed seeds and adult tree neighbors in a diverse rainforest in Madagascar, using a temporal and phylogenetic approach. Data show that by using fruiting trees as seed-dispersal foci, frugivores bias seed dispersal under conspecific adults and under heterospecific trees that share dispersers and fruiting time with the dispersed species. Frugivore-mediated seed dispersal also resulted in nonrandom phylogenetic associations of dispersed seeds with their nearest adult neighbors, in nine out of the 16 months of our study. However, these nonrandom phylogenetic associations fluctuated unpredictably over time, ranging from clustered to overdispersed. The spatial and phylogenetic template of seed dispersal did not translate to similar patterns of association in adult tree neighborhoods, suggesting the importance of post-dispersal processes in structuring plant communities. Results suggest that frugivore-mediated seed dispersal is important for structuring early stages of plant-plant associations, setting the template for post-dispersal processes that influence ultimate patterns of plant recruitment. Importantly, if biased patterns of dispersal are common in other systems, frugivores may promote tree coexistence in biodiverse forests by limiting the frequency and diversity of heterospecific interactions of seeds they disperse. © 2016 by the Ecological Society of America.

News Article | October 28, 2016

Two of Oakland Zoo’s Education staff are now in Madagascar as part of a three-year program developing conservation-based educational curriculum for grade school students in the country’s remote and impoverished villages. Daniel Flynn and Betty Vilallta of Oakland Zoo, along with representatives from Centre ValBio, Madagascar Ministry of Basic Education, Madagascar Ministry of Higher Education, University of Fianarantsoa, Stony Brook University in New York, and local Malagasy teachers and village leaders have teamed together to develop and launch a new educational curriculum aimed to inspire and empower young girls and boys in impoverished and remote villages of Madagascar. Centre ValBio, a conservation partner to Oakland Zoo dedicated to lemur research and conservation in Madagascar, approached the Zoo’s Education Department in 2015 about the program, and for the second year in a row the Zoo has sent two education specialist staff to be part of the “brain trust” tasked in developing and carrying out conservation-focused, locally relevant curriculum and education aids used in the new alternative method in teaching and learning, titled “My Rainforest, My World.” The project, funded by a three-year grant from Three Graces Foundation, is intended to help the children learn more effectively in science and to develop critical thinking skills - encouraging them to continue their education into middle school and beyond. Currently, the average age of girls and boys opting out of formal education in Madagascar is 4th grade and younger, with some as young as 13 marrying and starting families of their own. Since the program’s launch last year, the number of participating schools has doubled from ten to twenty. The schools are located in very rural farming communities, with little to no classroom resources, most of the program schools have no running water or electricity. Upon arriving in Madagascar, Oakland Zoo’s educators delivered 200 pounds of classroom supplies and $700 donated by Zoo staff, Bay Area schools and businesses to the participating schools. Oakland Zoo is also auctioning off a behind-the-scenes experience with lemurs, native to Madagascar, to raise much needed funds for the purchase of additional school supplies. In addition to developing curriculum and educational aids in collaboration with Centre ValBio, located in Southeastern Madagascar, the project hopes to expand the frontiers of knowledge while safeguarding biodiversity for future generations. A key component of the project involves recruiting and training student teacher interns to aid in the classrooms. These interns will help administer and teach the new curriculum in the schools under the direction and guidance of Centre ValBio and Oakland Zoo; and students will be taught hands-on science through the Zoo’s participatory educational models and theories which they can then use when they graduate. This effort marks the third hands-on collaboration between Oakland Zoo and Centre ValBio. Last year, zookeepers Margaret Rousser and Elizabeth Abram travelled to Madagascar to assist in the capture and data collection of the park’s Milne-Edward sifaka’s (lemurs, which are critically endangered). Oakland Zoo is thrilled to work on yet another project in Madagascar that directly benefits the local people and native wildlife. The Bay Area's award-winning Oakland Zoo is home to more than 660 native and exotic animals. The Zoo offers many educational programs and kid's activities perfect for science field trips, family day trips and exciting birthday parties. Oakland Zoo is dedicated to the humane treatment of animals and wildlife conservation onsite and worldwide; with 25¢ from each ticket donated to support conservation partners and programs around the world. The California Trail, a transformational project that more than doubles our size, opens in 2018, and will further our commitment to animal care, education, and conservation with a focus on this state’s remarkable native wildlife. Nestled in the Oakland Hills, in 500-acre Knowland Park, the Zoo is located at 9777 Golf Links Road, off Highway 580. The East Bay Zoological Society (Oakland Zoo) is a nonprofit 501(c)3 organization supported in part by members, contributions, the City of Oakland and the East Bay Regional Parks. For more information, go to: Centre ValBio was created by Professor Patricia Wright in 2003 to help both indigenous people and the international community better understand the value of conservation in Madagascar and around the world. CVB’s mission has three main objectives, which are: to promote world-class research in one of the world’s most biologically diverse and unique ecosystems; to encourage environmental conservation by developing ecologically sustainable economic development programs with local villages; to provide the local villagers with the knowledge and tools to improve their quality of life through projects focused on sanitation, diet, and education, and ultimately reduce poverty in the area.

Tecot S.R.,University of Arizona | Tecot S.R.,State University of New York at Stony Brook | Tecot S.R.,Center ValBio | Tecot S.R.,University of Texas at Austin
International Journal of Primatology | Year: 2010

Highly seasonal breeding has been considered one of the keys to understanding Malagasy primate socioecology. Strict seasonal breeding may be particularly critical for Malagasy primates because they live in such energetically challenging seasonal environments. Lemurs also live in highly unpredictable environments, and there is growing evidence that reproductive timing may be mediated by additional factors, suggesting that more relaxed breeding seasonality is adaptive in some cases. I tested the adaptive breadth of the birth peak in Eulemur rubriventer, which breed in several different months. I describe reproduction in the species by determining the timing and extent of the birth season (period in which all births occur) and birth peak (period in which the majority of births occur); test whether relaxed reproductive seasonality might increase reproductive success by comparing infant mortality within and outside the birth peak; and model the extent to which fruit availability has an influence on the timing of reproduction. I collected birth data on 5 groups in 2003-2005, which I combined with demographic data that D. Overdorff collected from 5 focal groups and additional censused groups between 1988 and 1996. Thirty births occurred in 8 different months. Births were significantly seasonal, with a unimodal birth peak in late August/September/October, and a mean birth date of October 11. Twenty-three births (76.7%) occurred within 54 d (14.79%) of the year. No births occurred May-July, indicating that conceptions did not occur from late December through late February, and cycling (estimated using gestation length) did not occur until ca. 101 d after the austral summer solstice (December 21). Of 22 infants followed regularly, 18 were born in the birth peak, of which 2 died (11%). All 4 infants born out of season died. Based on fruit availability, I calculated a Theoretical Overlap index (T), which indicated a 3-mo window with optimal food conditions for reproduction. This window corresponded to the timing and breadth of the birth peak in Eulemur rubriventer. These results indicate that a breeding season >3 mo within a given year is not adaptive in the species, likely due in large part to the availability of fruit during key reproductive stages, particularly before breeding. © 2010 Springer Science+Business Media, LLC.

Tecot S.R.,University of Arizona | Tecot S.R.,Center ValBio | Gerber B.D.,Colorado State University | King S.J.,University of Massachusetts Amherst | And 3 more authors.
Behavioral Ecology | Year: 2013

Sexually selected traits and the use of strategies to enhance male reproductive success (e.g., competition and dispersal) can yield sex differences in metabolic requirements, rates and durations of growth and maturation, and the propensity for risky behavior, which are suggested to result in age-specific sex differences in mortality and life span. We investigated age-specific sex ratios, mortality, and dispersal in Propithecus edwardsi in Ranomafana National Park, Madagascar. We predicted that, due to similarities in growth rates and body sizes, male and female juvenile mortality rates would be comparable; because both sexes disperse and have intense intersexual competition and aggression, adult mortality would be similar; given similarities in dispersal frequency and distance, the timing of dispersal would not differ. We used 80 group-years births, deaths, and dispersals (Nfemales = 41, N males = 34) collected over 23 years to calculate sex ratios and survival curves. Females lived longer than males (maximum 32 and 19 years, respectively). Sex ratios were male biased from sexual maturity through 17 years and female biased at birth and older ages. Infant survival probabilities were similar. Thus, differential development and maturation are unlikely explanations for longer female life span in this species. Males were more likely to survive from 2 to 18 years. However, male annual survival probability declined quickly around 13-18 years; males continued to disperse until their deaths, whereas females generally stopped dispersing after 11 years. We suggest that sex differences in the timing of dispersal and the unique challenges of risky behavior at older ages may be sufficient to yield differences in male and female life span. © 2013 The Author. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved.

Zohdy S.,Emory University | Zohdy S.,Center ValBio | Derfus K.,Emory University | Andrianjafy M.T.,University of Antananarivo | And 4 more authors.
Parasites and Vectors | Year: 2015

Background: Malaria is the 4th largest cause of mortality in Madagascar. To better understand malaria transmission dynamics, it is crucial to map the distribution of the malaria vectors, mosquitoes belonging to the genus Anopheles. To do so, it is important to have a strong Anopheles-specific lure to ensure the maximum number of captures. Previous studies have isolated volatiles from the human skin microbiota and found the compound 3-methyl-1-butanol to be the most attractive to the malaria mosquito, Anopheles gambiae, in a laboratory setting; and recommended 3-methyl-1-butanol as a compound to increase An. gambiae captures in the field. To date, this compound's ability to lure wild mosquitoes in differing land-use settings has not been tested. In this study, we evaluate the role of the synthetic compound, 3-methyl-1-butanol in combination with field produced CO2 in attracting Anopheles mosquitoes in varying land-use sites in Madagascar. Methods: CDC miniature light traps in combination with field produced CO2 were deployed in and around six villages near Ranomafana National Park, Madagascar. To test the role of 3-methyl-1-butanol in luring Anopheles mosquitoes, two traps were set in each land-use site (village, agricultural sites, and forested habitats affiliated with each village). One was baited with the synthetic odor and the other was kept as a non-baited control. Results: While 3-methyl-1-butanol baited traps did capture An. gambiae s.l. in this study, we did not find traps baited with synthetic 3-methyl-1-butanol to be more successful in capturing Anopheles mosquitoes, (including Anopheles gambiae s.l.) than the non odor-baited control traps in any of the land-use sites examined; however, regardless of odor bait, trapping near livestock pens resulted in the capture of significantly more Anopheles specimens. Conclusions: A strong synthetic lure in combination with insecticide has great potential as a mosquito control. Our findings suggest that trapping mosquitoes near livestock in malaria endemic regions, such as Madagascar, may be more successful at capturing Anopheles mosquitoes than the proposed 3-1-methyl-butanol lure. © 2015 Zohdy et al.; licensee BioMed Central.

Gerber B.,Virginia Polytechnic Institute and State University | Karpanty S.M.,Virginia Polytechnic Institute and State University | Crawford C.,Virginia Polytechnic Institute and State University | Kotschwar M.,Virginia Polytechnic Institute and State University | Randrianantenaina J.,Center ValBio
ORYX | Year: 2010

Despite major efforts to understand and conserve Madagascars unique biodiversity, relatively little is known about the islands carnivore populations. We therefore deployed 43 camera-trap stations in Ranomafana National Park, Madagascar during June-August 2007 to evaluate the efficacy of this method for studying Malagasy carnivores and to estimate the relative abundance and density of carnivores in the eastern rainforest. A total of 755 camera-trap nights provided 1,605 photographs of four endemic carnivore species (fossa Cryptoprocta ferox, Malagasy civet Fossa fossana, ring-tailed mongoose Galidia elegans and broad-striped mongoose Galidictus fasciata), the exotic Indian civet Viverricula indica and the domestic dog Canis familiaris. We identified 38 individual F. fossana and 10 individual C. ferox. We estimated density using both capture-recapture analyses, with a buffer of full mean-maximum-distance-moved, and a spatially-explicit maximum-likelihood method (F. fossana: 3.03 and 2.23 km-2, respectively; C. ferox: 0.15 and 0.17 km-2, respectively). Our estimated densities of C. ferox in rainforest are lower than published estimates for conspecifics in the western dry forests. Within Ranomafana National Park species richness of native carnivores did not vary among trail systems located in secondary, selectively-logged and undisturbed forest. These results provide the first assessment of carnivore population parameters using camera-traps in the eastern rainforests of Madagascar. Copyright © 2010 Fauna & Flora International.

Gerber B.D.,Virginia Polytechnic Institute and State University | Karpanty S.M.,Virginia Polytechnic Institute and State University | Randrianantenaina J.,Center ValBio
ORYX | Year: 2012

Forest carnivores are threatened globally by logging and forest fragmentation yet we know relatively little about how such change affects predator populations. This is especially true in Madagascar, where carnivores have not been extensively studied. To understand better the effects of logging and fragmentation on Malagasy carnivores we evaluated species composition, density of fossa Cryptoprocta ferox and Malagasy civet Fossa fossana, and carnivore occupancy in central-eastern Madagascar. We photographically-sampled carnivores in two contiguous (primary and selectively-logged) and two fragmented rainforests (fragments <2.5 and >15 km from intact forest). Species composition varied, with more native carnivores in the contiguous than fragmented rainforests. F. fossana was absent from fragmented rainforests and at a lower density in selectively-logged than in primary rainforest (mean 1.38±SE 0.22 and 3.19±SE 0.55 individuals km-2, respectively). C. ferox was detected in fragments <2.5 km from forest and had similar densities in primary and selectively-logged forests (0.12±SE 0.05 and 0.09±SE 0.04 adults km-2, respectively) but was absent in fragments >15 km from forest. We identified only two protected areas in Madagascar that may maintain >300 adult C. ferox. Occupancy of broad-striped mongoose Galidictis fasciata was positively related to fragment size whereas occupancy of ring-tailed mongoose Galidia elegans elegans was negatively associated with increasing exotic wild cat (Felis spp.) activity at a camera site. Degraded rainforest fragments are difficult environments for Malagasy carnivores to occupy; there is a need to prioritize the reconnection and maintenance of contiguous forest tracts. © 2012 Fauna & Flora International.

Gerber B.D.,Virginia Polytechnic Institute and State University | Karpanty S.M.,Virginia Polytechnic Institute and State University | Randrianantenaina J.,Center ValBio
Journal of Mammalogy | Year: 2012

Temporal partitioning of activity among sympatric species can be an important mechanism for species coexistence. Further, if exotic and native species overlap temporally, there is potential for direct competition and antagonism, which may lead to native species extirpation. We 1st assessed if ecologically similar native carnivores of Madagascar demonstrated activity pattern overlap and then explored whether overlap in activity might lead to negative impacts of exotic carnivores on native carnivores. We used photographic sampling to quantify the temporal activity patterns of carnivores at 4 study sites. The activity of the 2 smaller-bodied native species, Galidia elegans and Galidictis fasciata, overlapped minimally; these 2 carnivores share a similar generalist diet, which may drive their divergent temporal activity. In contrast, the medium-sized native species, Fossa fossana and Eupleres goudotii, were both highly nocturnal; these 2 species appear segregated in their diets. The largest native carnivore, Cryptoprocta ferox, selectively used crepuscular hours, but overall was cathemeral; it was notably absent or basically so at sites where dogs were most abundant and active throughout the diel cycle. We found G. elegans to shift from preferred activity periods in the presence of dogs and the exotic Viverricula indica. Our results suggest that the presence and activity of exotic carnivores can negatively impact native carnivores in fragmented rain forests. © 2012 American Society of Mammalogists.

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