Discovery of Macrotarsomys bastardi at Beza Mahafaly Special Reserve, southwest Madagascar, with observations on the dynamics of small mammal interactions

We report the presence of Macrotarsomys bastardi, Bastard’s big - footed mouse, at the Beza Mahafaly Special Reserve in southwestern Madagascar. Despite years of fieldwork, including field research targeting the nocturnal mammals, this species had never been reported here previously. A program of intensive and random capture of nocturnal mammals was established over a period of one year (October 2006 to September 2007). We monitored the relative abundances and microhabitat preferences of small - bodied nocturnal mammals in three forests at Beza, as reflected in trapping success both on the ground and at heights of one to two meters in the trees. Three species are common at Beza (although they have different apparent habitat preferences): Microcebus griseorufus, Rattus rattus, and Echinops telfairi. Endemic rodents appear to be rare. Possible interactions between introduced rodents (rats and mice) and endemic species of rodents (Macrotarsomys and Eliurus) are also discussed

Multiple ectoparasites infest Microcebus griseorufus at Beza Mahafaly Special Reserve, Madagascar

The mouse lemur Microcebus griseorufus at the Beza Mahafaly Special Reserve and general vicinity in southwestern Madagascar were surveyed for ectoparasites as part of a year-long behavioral and ecological study. Of 249 individual mouse lemurs examined, 74 were positively identified as hosting ectoparasites. Ticks from 20 mouse lemurs and lice in a subset of two individuals captured in a 90 ha gallery forest (Parcel 1) were preserved in 70 % ethanol or EDTA and stored for analysis and for identification. Two species of Haemaphysalis ticks are represented in the sample, H. lemuris and possibly H. simplex, a tick previously reported on tenrecs, birds and rats. Synchronous development of ticks may pose a risk for vector - borne diseases at the reserve especially during the dry season. The louse represented in the sample belongs to the order Anoplura (sucking lice), and resembles Lemurpediculus verruculosus, previously reported on Microcebus rufus in eastern Madagascar.RÉSUMÉUn inventaire d’ectoparasites a été réalisé dans le cadre d’une étude de longue durée portant sur le comportement et l’écologie de Microcebus griseorufus dans trois parcelles forestières de Beza Mahafaly et ses environs. Sur les 249 microcèbes observés, 74 individus étaient infestés d’ectoparasites. La majorité de ces individus infestés, soit 97,3 % , provenait de la parcelle 1 de la réserve. Des poux et des tiques recensés sur ces animaux ont été immédiatement retirés puis préservés dans l’éthanol 70 % ou dans l’EDTA à des fins d’analyse et d’identification. Deux espèces de tiques ont été identifiées, Haemaphysalis lemuris et probablement H. simplex, cette dernière n’était préalablement connue que pour infester les tenrecs, les oiseaux et les rats. Les rongeurs jouent un rôle significatif en tant qu’hôtes pour près de la moitié des larves et des nymphes d’ixodes de tiques du monde, y compris H. simplex. Les rats sont connus pour être des porteurs d’une population importante de différentes tiques. Ils sont ainsi les hôtes avec la plus grande tolérance. Une nouvelle forme de transmission a été identifiée à Beza Mahafaly dans laquelle H. simplex et d’autres espèces de tiques ont simultanément infesté des tenrecs. Ce chevauchement de plusieurs parasites forme une sorte de réserve et favorise la transmission des agents pathogènes à travers les espèces hôtes. Les tiques immatures jouent un rôle significatif dans la transmission des maladies véhiculées par les hôtes car les nymphes ainsi infectées peuvent transmettre des pathogènes aux hôtes et aux larves engorgées. À Beza Mahafaly, le microcèbe pourrait être l’hôte des formes immatures des tiques de H. lemuris et H. simplex chez lesquelles le stade larvaire et le stade nymphal sont synchrones. Ces formes immatures de tiques se nourrissent ensemble sur des individus de microcèbes. Les poux appartiennent à l’ordre des Anoploures (poux suceurs) et ressemblent à Lemurpediculus verruculosus qui n’était connu que pour infester Microcebus rufus des forêts humides de Ranomafana.Il est possible que M. griseorufus accueille sa propre espèce de Lemurpediculus, si ce n’est le cas, il faudra admettre que la spécificité de cet arthropode serait moins limitée qu’elle ne le semblait. Pour comprendre la dynamique des parasites de la réserve, des études sur l’écologie des tiques et des poux sont recommandées afin de pouvoir contribuer effectivement à l’amélioration de la protection de la réserve

Spatial memory in the grey mouse lemur (Microcebus murinus)

Wild animals face the challenge of locating feeding sites distributed across broad spatial and temporal scales. Spatial memory allows animals to find a goal, such as a productive feeding patch, even when there are no goal-specific sensory cues available. Because there is little experimental information on learning and memory capabilities in free-ranging primates, the aim of this study was to test whether grey mouse lemurs (Microcebus murinus), as short-term dietary specialists, rely on spatial memory in relocating productive feeding sites. In addition, we asked what kind of spatial representation might underlie their orientation in their natural environment. Using an experimental approach, we set eight radio-collared grey mouse lemurs a memory task by confronting them with two different spatial patterns of baited and non-baited artificial feeding stations under exclusion of sensory cues. Positional data were recorded by focal animal observations within a grid system of small foot trails. A change in the baiting pattern revealed that grey mouse lemurs primarily used spatial cues to relocate baited feeding stations and that they were able to rapidly learn a new spatial arrangement. Spatially concentrated, non-random movements revealed preliminary evidence for a route-based restriction in mouse lemur space; during a subsequent release experiment, however, we found high travel efficiency in directed movements. We therefore propose that mouse lemur spatial memory is based on some kind of mental representation that is more detailed than a route-based network map

Small-scale coexistence of two mouse lemur species (Microcebus berthae and M. murinus) within a homogeneous competitive environment

Understanding the co-occurrence of ecologically similar species remains a puzzling issue in community ecology. The species-rich mouse lemurs (Microcebus spec.) are distributed over nearly all remaining forest areas of Madagascar with a high variability in species distribution patterns. Locally, many congeneric species pairs seem to co-occur, but only little detailed information on spatial patterns is available. Here, we present the results of an intensive capture–mark–recapture study of sympatric Microcebus berthae and M. murinus populations that revealed small-scale mutual spatial exclusion. Nearest neighbour analysis indicated a spatial aggregation in Microcebus murinus but not in M. berthae. Although the diet of both species differed in proportions of food categories, they used the same food sources and had high feeding niche overlap. Also, forest structure related to the spatial distribution of main food sources did not explain spatial segregation because parts used by each species exclusively did not differ in density of trees, dead wood and lianas. We propose that life history trade-offs that result in species aggregation and a relative increase in the strength of intra-specific over inter-specific competition best explain the observed pattern of co-occurrence of ecologically similar congeneric Microcebus species

Demise of the Bet Hedgers: A Case Study of Human Impacts on Past and Present Lemurs of Madagascar

We live in an era marked by an accelerating rate of species death, but since the early days of the discipline, anthropology has contemplated the death of languages, cultural groups, and ways of life. The essays in this collection examine processes of—and our understanding of—extinction across various domains. The contributors argue that extinction events can be catalysts for new cultural, social, environmental, and technological developments—that extinction processes can, paradoxically, be productive as well as destructive. The essays consider a number of widely publicized cases: island species in the Galápagos and Madagascar; the death of Native American languages; ethnic minorities under pressure to assimilate in China; cloning as a form of species regeneration; and the tiny hominid Homo floresiensis fossils ( hobbits ) recently identified in Indonesia. The Anthropology of Extinction offers compelling explorations of issues of widespread concern

Morphological variability or inter‐observer bias? A methodological toolkit to improve data quality of multi‐researcher datasets for the analysis of morphological variation

International audienceObjectives: The investigation of morphological variation in animals is widely used in taxonomy, ecology, and evolution. Using large datasets for meta-analyses has dramatically increased, raising concerns about dataset compatibilities and biases introduced by contributions of multiple researchers.Materials and Methods: We compiled morphological data on 13 variables for 3073 individual mouse lemurs (Cheirogaleidae, Microcebus spp.) from 25 taxa and 153 different sampling locations, measured by 48 different researchers. We introduced and applied a filtering pipeline and quantified improvements in data quality (Shapiro-Francia statistic, skewness, and excess kurtosis). The filtered dataset was then used to test for genus-wide sexual size dimorphism and the applicability of Rensch's, Allen's, and Bergmann's rules.Results: Our pipeline reduced inter-observer bias (i.e., increased normality of data distributions). Inter-observer reliability of measurements was notably variable, highlighting the need to reduce data collection biases. Although subtle, we found a consistent pattern of sexual size dimorphism across Microcebus, with females being the larger (but not heavier) sex. Sexual size dimorphism was isometric, providing no support for Rensch's rule. Variations in tail length but not in ear size were consistent with the predictions of Allen's rule. Body mass and length followed a pattern contrary to predictions of Bergmann's rule.Discussion: We highlighted the usefulness of large multi-researcher datasets for testing ecological hypotheses after correcting for inter-observer biases. Using genus-wide tests, we outlined generalizable patterns of morphological variability across all mouse lemurs. This new methodological toolkit aims to facilitate future large-scale morphological comparisons for a wide range of taxa and applications

Sleeping and Ranging Behavior of the Sambirano Mouse Lemur, Microcebus sambiranensis

Primates require secure sleeping sites for periods of rest, but despite their importance, the characteristics of desired sleeping sites are poorly known. Here we investigated the sleeping ecology of a radio-collared population of the Sambirano mouse lemur, Microcebus sambiranensis, during the nonreproductive season in the Anabohazo forest, northwestern Madagascar. We also investigated their ranging behavior and examined the spatial distribution of sleeping sites within the home ranges of the collared individuals. We took measurements of the sleeping tree’s physical characteristics and recorded the number of collared individuals using each sleeping site. We found that M. sambiranensis generally use foliage sleeping sites more frequently than tree holes and individuals slept more frequently in densely foliated trees than in sparsely foliated trees, often alone. We observed no significant differences in home range size or nightly travel distance between males and females; however, home ranges were smaller than those described for other mouse lemur species. Finally, we found that M. sambiranensis sleep peripherally and forage centrally within their home ranges, a behavior not previously described for mouse lemurs. Our results indicate profound differences in the social organization between M. sambiranensis and other mouse lemur species described in the literature, suggesting species-specificity in mouse lemur ecology. Understanding the sleeping ecology and ranging behavior of mouse lemurs is of great importance to their conservation, as these data facilitate the planning of long-term reforestation, habitat management, and population assessment.</p