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

Nonalimentary tooth use in prehistory: An example from early Holocene in Central Sahara (Uan Muhuggiag, Tadrart Acacus, Libya)

Signs of nonalimentary tooth use were observed on the dentition of an adult male from a single burial excavated in an area close to the Uan Muhuggiag rock shelter (Tadrart Acacus, Libya), dated to more than 7800 uncalibrated years BP, that represents the most ancient human remain found in the Libyan Sahara, and provides a first glimpse of human adaptation in the early Holocene of this region. The wear pattern shows large grooves running across the occlusal surfaces of maxillary and mandibular anterior teeth and premolars. The results of macroscopic and microscopic observation, together with scanning electron microscope (SEM) examination and experimental tests, suggest that the microdamage might be due to repeated friction of vegetal fibers, probably as a consequence of basket making, net production, or mat processing. Further data are needed to allow us to distinguish among plant-oriented activities related to food acquisition (e.g., rope and net processing), food storage (e.g., basket making), or domestic handicraft (e.g., mat processing), whose implications may generate different interpretations of sexual division of labor

Proximate and ultimate determinants of cathemeral activity in brown lemurs

Among primates, only two lemur genera, Eulemur and Hapalemur, and a population of the platyrrhine Aotus azarai are known to be cathemeral (i.e. show a mixture of daytime and night-time activity). Given the rarity of this phenomenon in primates except for Malagasy lemurs, its proximate and ultimate factors are still debated. The adaptive reasons for this apparently odd lifestyle are mainly based on four not mutually exclusive hypotheses: thermoregulatory benefits, antipredator strategy, competition avoidance and metabolic dietary-related needs. However, little effort has been made to tease apart proximate cues from potential ultimate factors in the multivariate context of activity correlates. To investigate these hypotheses, we compared the year-round cathemeral activity of two groups of Eulemur collaris and one group of hybrids E. collaris  Eulemur fulvus rufus in a humid littoral and in a dry gallery forest of southern Madagascar. Data were collected using a 5 min instantaneous method, with sampling equally distributed between day and night. We weighted the different effects of proximate and ultimate factors via the ANCOVA analysis using as the dependent variable the ratio between diurnal and nocturnal activity. Photoperiodic changes and nocturnal luminosity were the two proximate factors that accounted for most of the variability at the two sites. Diet quality was the only ultimate factor that had a significant effect on the diurnality index of the two lemur populations, suggesting a role of metabolic dietary-related needs in determining cathemeral activity in these lemurs.

Living in Islands of Forests: Nutritional Ecology of the Howler Monkey ( Alouatta palliata) at La Suerte Biological Field Station, North-Eastern Costa Rica

This unique book allows to be used as a textbook and a resource in field schools and universities, as well as for field research. It can easily provide a general and deep overview, as well serve as a species and inventory guide of Central American biodiversity, its natural resources and habitats for some of the most prolific habitats: the low elevation rainforest (location of La Suerte Biological station, Costa Rica), the tropical dry forest and lake system (location of the Ometepe Island station, Nicaragua), and Central America as a whole (including its unique coastal, marine and atmospheric heritage). These land—and seascapes are globally praised for their huge and unique species richness, but are also known for their fast decay. This book fills a niche, and it is based on over a decade of teaching and research experience of the main author, his international colleagues and students at both sites run by the Maderas Rainforest Conservancy The authors also have a wide experience with the historical and international context and with the political ecology for the region, as well as with analyzing complex biodiversity and landscapes, the Caribbean, Central America, and with open access geographic information system (GIS) data and modeling; this emphasize is shared here with the audience. Locally, the two field sites featured cover many relevant habitats (tropical rainforest, dry forest, freshwater, volcano, cloud forest, Caribbean and Pacific coast, agriculture). The conservation urgency regarding biodiversity and tropical forest loss, habitat conversion, and its social decay does hardly need further mentioning and in times of ongoing climate change and globalization. Unique data have been compiled in this publication for the first time (digitally, with GIS and online). This book tackles wildlife management in the tropics: from sea turtles and sea floor benthos over plants and trees to insects, birds, small mammals, monkeys, sloths, tapirs, amphibians, and reptiles. The digital online appendix of this book provides relevant and highly seeked-after background material for any naturalist, e.g., digital species check lists for field stations, GIS maps, course syllabi, and photos

Time spent by collared lemurs eating on the various food categories at the two study sites.

<p>Upper quadrant: monthly percentages of feeding records. Lower quadrant: residuals of log-transformed feeding records controlling for log-transformed group size. Values are means and standard errors. STL: Sainte Luce; MAN: Mandena; * p<.05.</p

Effects of site and group size on lemur time-budget and diet according to one-way analyses of covariance.

<p>Analyses were performed on log-transformed data. Values are F-values.</p><p>*p<0.05.</p><p>**p<0.01.</p