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The phylogenetic diversity of extant lemurs represents one of the most important but least studied aspects of the conservation biology of primates. The phylogenetic diversity of a species is inversely proportional to the relative number and closeness of its phylogenetic relatives. Phylogenetic diversity can then be used to determine conservation priorities for specific biogeographic regions. Although Malagasy strepsirhines represent the highest phylogenetic diversity among primates at the global level, there are few phylogenetic data on species-specific and regional conservation plans for lemurs in Madagascar. Therefore, in this paper the following questions are addressed for extant lemurs: 1) how does the measure of taxonomic uniqueness used by Mittermeier et al. ([1992] Lemurs of Madagascar; Gland, Switzerland: IUCN) equate with an index of phylogenetic diversity, 2) what are the regional conservation priorities based on analyses of phylogenetic diversity in extant lemurs, and 3) what conservation recommendations can be made based on analyses of phylogenetic diversity in lemurs? Taxonomic endemicity standardized weight (TESW) indices of phylogenetic diversity were used to determine the evolutionary component of biodiversity and to prioritize regions for conserving lemur taxa. TESW refers to the standardization of phylogenetic diversity indices for widespread taxa and endemicity of species. The phylogenetic data came from recent genetic studies of Malagasy strepsirhines at the species level. Lemur species were assigned as being either present or absent in six biogeographic regions. TESW indices were combined with data on lemur complementarity and protected areas to assign conservation priorities at the regional level. Although there were no overall differences between taxonomic ranks and phylogenetic rankings, there were significant differences for the top-ranked taxa. The phylogenetic component of lemur diversity is greatest for Daubentonia madagascariensis, Allocebus trichotis, Lepilemur septentrionalis, Indri indri, and Mirza coquereli. Regional conservation priorities are highest for lemurs that range into northeast humid forests and western dry forests. Expansion of existing protected areas in these regions may provide the most rapid method for preserving lemurs. In the long term, new protected areas must be created because there are lemur species that: 1) are not found in existing protected areas, 2) exist only in one or two protected areas, and 3) are still being discovered outside the current network of protected areas. Data on the population dynamics and feeding ecology of phylogenetically important species are needed to ensure that protected areas adequately conserve lemur populations in Madagascar. KEY WORDS phylogenetic diversity; complementarity; endemism; protected areas; lemurs; Madagascar

Forest edges are dynamic zones characterized by the penetration of conditions from the surrounding environment into the forest interior and changes in population dynamics as a consequence of edge effects can be defined as indirect biological effects. Although edge effects influence many tropical organisms they are particularly relevant to lemurs because of the highly fragmented forest landscapes found in Madagascar.

Edge effects are caused by the penetration of abiotic and biotic conditions from the matrix into forest interiors. Although edge effects influence the biogeography of many tropical organisms, they have not been studied directly in primates. Edge effects are particularly relevant to lemurs due to the loss of 80-90% of forests in Madagascar. In this study, data are presented on how biotic edge effects influenced the distribution and density of lemurs in the Vohibola III Classified Forest in southeastern Madagascar. In total, 415 lemur surveys were conducted during June-October 2003 and May--September 2004 along six 1,250-m transects that ran perpendicular to the forest edge. Data were also collected on lemur food trees along the six transects (density, height, diameter at breast height, area, volume, and distance to forest edge). Four nocturnal species (Avahi laniger, Cheirogaleus major, Lepilemur microdon, and Microcebus rufus) and four diurnal species (Eulemur rubriventer, Eulemur fulvus rufus, Hapalemur grisesus griseus, and Propithecus diadema edwardsi) were sighted during surveys. Regression analyses of lemur densities as a function of distance to forest edge provided edge tolerances for A. laniger (edge-tolerant), M. rufus (edge-tolerant), E. rubriventer (edge-tolerant or omnipresent), and H. g. griseus (omnipresent). The density and distribution of M. rufus and their foods trees were correlated. Edge-related variations in food quality and predation pressures may also be influencing lemurs in Vohibola III. Tolerance for edge effects may explain, in part, how lemurs have survived extreme habitat loss and forest fragmentation in southeastern Madagascar. KEY WORDS forest fragmentation; diet; food quality; predation; protected areas

Ecogeographic size variations have been documented in some but not all sifakas. Few morphometric or body weight data have been available for two critically endangered subspecies of diademed sifakas: Perrier's sifakas (Propithecus diadema perrieri) and silky sifakas (Propithecus diadema candidus). The objectives of our study were to determine size variations in sifakas and if these variations are related to resource quality and/or resource seasonality. P. d. perrieri and P. d. candidus were captured, weighed, and measured in northern Madagascar. Body weights and morphometrics were compared with other subspecies of diademed sifakas and indris (Indri indri). Differences in body weights and morphometrics between taxa are particularly pronounced for P. d. perrieri compared to P. d. diadema, P. d. edwardsi, and I. indri. Most morphometrics varied in comparisons between P. d. candidus and the other Indriidae (P. d. diadema, P. d. edwardsi, and I. indri). Average body size in sifakas is positively correlated with annual rainfall and negatively correlated with length of dry season. Sifaka body size is not correlated with protein-to-fiber ratios. Thus, size variations in sifakas are related to resource seasonality rather than resource quality. The relationships between the temporal availability of food resources and sifaka body size reflect complex and regionally varying causalities. Detailed, longitudinal information on the ecological factors underlying food selection and nutrient requirements in sifakas are needed to determine the relationship between ecogeographic variables and body size in sifakas. KEY WORDS Propithecus diadema perrieri; Propithecus diadema candidus; biogeography; morphometrics; rainfall; protein-to-fiber ratios; Madagascar

Habitat loss and fragmentation are major ecological forces threatening animal communities across the globe. These issues are especially true in Madagascar, where forest loss is ongoing. We examined the effects of forest fragmentation on the distribution and abundance of sympatric, endemic gray, and golden‐brown mouse lemurs (Microcebus murinus and Microcebus ravelobensis), the endemic western tuft‐tailed rat (Eliurus myoxinus), and the invasive black rat (Rattus rattus) in two regions in northwestern Madagascar. We used systematic capture procedures in 40 forest fragments and four continuous forest sites which differed in size, shape, and degree of isolation. With a trapping effort of 11,567 trap nights during two dry seasons (2017–2018), we captured 929 individuals (432 M. ravelobensis, 196 M. murinus, 116 E. myoxinus, and 185 R. rattus). We examined the influence of study region, forest type (fragment vs. continuous), forest size, forest shape, the proportion of 50‐m forest edge and distance to continuous forest on the abundance and interaction of the four species. Responses to fragmentation differed strongly between species, but no interaction could be detected between the abundance of the different species. Thus competition within and between native and invasive species may not be regulating abundances in these regions. On the contrary, the abundance of M. ravelobensis and E. myoxinus differed significantly between study regions and was negatively affected by fragmentation. In contrast, there was no evidence of an impact of fragmentation on the abundance of M. murinus. Finally, the invasive R. rattus responded positively to the increasing distance to the continuous forest. In conclusion, the response of small Malagasy mammals to forest fragmentation varies largely between species, and fragmentation effects need to be examined at a species‐specific level to fully understand their ecological dynamics and complexity. Research Highlights: Habitat fragmentation affects the abundance of mouse lemurs and rodents differently.Endangered Microcebus ravelobensis and Eliurus myoxinus are more sensitive to fragmentation than Microcebus murinus and Rattus rattus.There was no evidence for interspecific competition. [ABSTRACT FROM AUTHOR]

A study was made with a main goal to determine the way habitat variation influences dietary patterns in Perrier's sifakas that range into both dry and riparian forest in northern Madagascar. 542 hr of data was collected on the behavior and diet of two groups of perrieri from 7June to 4 August 1998 at camp Antobiratsy in Analamera special reserve, Madagascar.

Although roads are often assumed to be barriers to the dispersal of arboreal species, there has been little empirical testing of this assumption. If arboreal animals are unable to cross roads, population subdivision may occur, or resources may become inaccessible. We tested the hypothesis that Route Nationale 4 (RN4), a paved highway, was a barrier to movement and dispersal of the Endangered golden-brown mouse lemur Microcebus ravelobensis in Ankarafantsika National Park, in north-west Madagascar. During June–August 2015 we conducted a capture–mark–recapture study at three sites: two adjacent to RN4 and one within intact forest without a potential barrier. During 2,294 trap nights we captured 120 golden-brown mouse lemurs 1,032 times. In roadside habitats we captured significantly more males than females, whereas the opposite was the case in interior forest habitat. We detected eighteen crossings of highway transects by nine individuals; however, all potential dispersal events involved males. In roadside habitat, movement was significantly inhibited in both males and females. We present some of the first data on the effects of roads on movement patterns in arboreal Malagasy mammals, showing species- and sex-biased effects of roads as dispersal barriers. Our findings indicate that roads may not be complete barriers to dispersal in lemurs. We recommend that conservation managers and scientists examine explicitly the effects of roads and natural arboreal bridges in Madagascar in future studies. [ABSTRACT FROM AUTHOR]