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Habitat fragmentation is an increasingly serious issue affecting primates in most regions where they are found today. Populations of Lemur catta (ring‐tailed lemur) in Madagascar's south‐central region are increasingly restricted to small, isolated forest fragments, surrounded by grasslands or small‐scale agriculture. Our aim was to evaluate the potential for population viability of L. catta in nine forest fragments of varying sizes (2–46 ha, population range: 6–210 animals) in south‐central Madagascar, using a set of comparative, quantitative ecological measures. We used Poisson regression models with a log link function to examine the effects of fragment size, within‐fragment food availability, and abundance of matrix resources (food and water sources) on L. catta population sizes and juvenile recruitment. We found a strong association between overall population size and (a) fragment size and (b) abundance of key food resources Melia azedarach and Ficus spp. (per 100 m along transect lines). Juvenile recruitment was also associated with fragment size and abundance of the two above‐mentioned food resources. When the largest population, an outlier, was removed from the analysis, again, the model containing fragment size and abundance of M. azedarach and Ficus spp. was the best fitting, but the model that best predicted juvenile recruitment contained only fragment size. While our results are useful for predicting population presence and possible persistence in these fragments, both the potential for male dispersal and the extent of human disturbance within most fragments play crucial roles regarding the likelihood of long‐term L. catta survival. While seven of the nine fragments were reasonably protected from human disturbance, only three offered the strong potential for male dispersal, thus the long‐term viability of many of these populations is highly uncertain. Research Highlights: Fragment size and occurrence rate of key food trees are important predictors of population viability in Lemur catta confined to fragments in south‐central Madagascar.Lack of male dispersal opportunities and ongoing anthropogenic disturbance of some fragments compromises such viability. [ABSTRACT FROM AUTHOR]

In group-living species with male dominance hierarchies where receptive periods of females do not overlap, high male reproductive skew would be predicted. However, the existence of female multiple mating and alternative male mating strategies can call into question single-male monopolization of paternity in groups. Ring-tailed lemurs ( Lemur catta) are seasonally breeding primates that live in multi-male, multi-female groups. Although established groups show male dominance hierarchies, male dominance relationships can break down during mating periods. In addition, females are the dominant sex and mate with multiple males during estrus, including group residents, and extra-group males-posing the question of whether there is high or low male paternity skew in groups. In this study, we analyzed paternity in a population of wild L. catta from the Bezà Mahafaly Special Reserve in southwestern Madagascar. Paternity was determined with 80-95% confidence for 39 offspring born to nine different groups. We calculated male reproductive skew indices for six groups, and our results showed a range of values corresponding to both high and low reproductive skew. Between 21% and 33% of offspring (3 of 14 or three of nine, counting paternity assignments at the 80% or 95% confidence levels, respectively) were sired by extra-troop males. Males siring offspring within the same group during the same year appear to be unrelated. Our study provides evidence of varying male reproductive skew in different L. catta groups. A single male may monopolize paternity across one or more years, while in other groups, >1 male can sire offspring within the same group, even within a single year. Extra-group mating is a viable strategy that can result in extra-group paternity for L. catta males. [ABSTRACT FROM AUTHOR]

Lemur catta's ability to consume a wide variety of plant foods is a key to this species' survival in a time of ecological crisis across its geographic range. We examined seasonal diet variability of L. catta groups inhabiting two rocky outcrop fragments in south-central Madagascar: Anja Reserve and Tsaranoro Valley forest. Leaves and fruit of Melia azedarach were a keystone resource for Anja lemurs in wet and dry seasons. At Tsaranoro, L. catta relied on M. azedarach and Ficus spp. in dry season, but during the wet season, neither was a dominant food resource. Top food species at both sites differed markedly from those consumed by L. catta in other habitats. At Tsaranoro, a greater proportion of lemurs engaged in feeding during the dry season compared with wet season. We attribute this to resource scarcity during dry season, when greater feeding effort is needed to maintain energy requirements. Because M. azedarach is ubiquitous throughout Anja Reserve, producing fruit and leaves year-round, Anja lemurs can meet energy requirements with little seasonal adjustment in feeding activity. L. catta's IUCN status has been upgraded to Endangered, thus, greater insight into its diet flexibility and ability to survive on introduced plant species, can inform conservation plans in remaining wild habitats and ex situ programs. [ABSTRACT FROM AUTHOR]

We examined the mechanisms guiding male affiliative relationships among ring-tailed lemurs {Lemur catta) to investigate the adaptive significance of male social bonds in a female dominant, strictly seasonally breeding strepsirhine primate. To test whether male affiliative relationships were driven by reproductive and/or ecological conditions, we compared the frequency of male affiliation across the annual reproductive cycle in populations of L. catta inhabiting three habitat types found within its geographic range: (1) gallery forest at Beza Mahafaly Special Reserve in southwestern Madagascar; (2) spiny bush at Cap Sainte-Marie (CSM) in southern Madagascar; and (3) rockyoutcrop forest fragments at Anja Reserve and the Tsaranoro Valley in Madagascar's south-central highlands. Each study period spanned the gestation, lactation/migration, post-migration, and mating periods. Inter-male affiliation rates varied across reproductive periods at each of the four sites, with the highest frequencies being observed during the gestation and lactation/migration periods and the lowest frequencies occurring during the mating period. In contrast, we found no clear patterns in male-female affiliation rates with respect to reproductive period. Comparing the Beza Mahafaly and CSM populations, rates of inter-male affiliation were higher at CSM during the gestation and lactation/migration periods, and rates male-female affiliation were higher at CSM across all seasons except the post-migration period. We suggest that inter-male affiliative relationships in L. catta may provide beneficial social interactions (i.e., grooming, ectoparasite control, predator protection, vigilance against extra-group male agonism) when females are unavailable, particularly during male dispersal, as well as under harsh climatic conditions characteristic of some L catta habitats. [ABSTRACT FROM AUTHOR]

Strong resource seasonality in Madagascar has led to the evolution of female feeding priority and weaning synchrony in most lemur species. For these taxa, pregnancy/early lactation periods coincide with low food availability, and weaning of infants is timed with increased resources at the onset of the rainy season. Reproductive females experience high metabolic requirements, which they must accommodate, particularly when food resources are scarce. Female ring-tailed lemurs ( Lemur catta) residing in spiny forest habitat must deal with resource scarcity, high temperatures (∼36-40°C) and little shade in early to mid-lactation periods. Considered 'income breeders,' these females must use resources obtained from the environment instead of relying on fat stores; thus, we expected they would differ from same-sized males in time spent on feeding and in the intake of food and nutrients. We investigated these variables in two groups ( N = 11 and 12) of Lemur catta residing in spiny forest habitat during early gestation and early to mid-lactation periods. Focal animal data and food plant samples were collected, and plants were analyzed for protein, kcal, and fiber. We found no sex differences for any feeding or nutrient intake variable for the top five food species consumed. Females in early gestation spent more time feeding compared with early/mid-lactation. Physiological compensation for spiny forest-dwelling females may be tied to greater time spent resting compared with gallery forest conspecifics, consuming foods high in protein, calories, and water, reduced home range defense in a sparsely populated habitat, and for Lemur catta females in general, production of relatively dilute milk compared with many strepsirrhines. Am J Phys Anthropol, 2011. © 2011 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

We compared diets and female feeding agonism in 2 groups of ring-tailed lemurs living in markedly diverse microhabitats in and near the Beza Mahafaly Reserve, Madagascar during mid-to-late gestation periods and height of the dry season to test predictions concerning differences in resource availability, preferred foods, female rank, and degree and frequency of feeding agonism in relation to usurpability and monopolization of food resources. Quadrat sampling in disturbed forest habitat revealed a greater number of plant species than in the gallery forest home range area, but females in both groups consumed nearly equal numbers of actual food plant species. Higher-ranking females in disturbed forest consumed human food scraps from the researchers camp significantly more often than low-ranking females did, while there was no rank effect for consumption of any food type between females in the gallery forest group. Higher rates of female feeding agonism in both groups occurred around usurpable fruit and leaves, as well as over monopolizable human food scraps in the disturbed forest group. There is no association between degree of agonism and food type in either group, and rate of feeding agonism is similar for both groups. The most highly contested food items came in large packages and were high in nutrients: beneficial foods for gestating females in the height of dry season in southwestern Madagascar. [ABSTRACT FROM AUTHOR]

Chemical deterioration of teeth is common among modern humans, and has been suggested for some extinct primates. Dental erosion caused by acidic foods may also obscure microwear signals of mechanical food properties. Ring-tailed lemurs at the Beza Mahafaly Special Reserve (BMSR), Madagascar, display frequent severe tooth wear and subsequent tooth loss. In contrast, sympatric Verreaux's sifaka display far less tooth wear and infrequent tooth loss, despite both species regularly consuming acidic tamarind fruit. We investigated the potential impact of dietary acidity on tooth wear, collecting data on salivary pH from both species, as well as salivary pH from ring-tailed lemurs at Tsimanampesotse National Park, Madagascar. We also collected salivary pH data from ring-tailed lemurs at the Indianapolis Zoo, none of which had eaten for at least 12 hr before data collection. Mean salivary pH for the BMSR ring-tailed lemurs (8.098, n=41, SD=0.550) was significantly more alkaline than Verreaux's sifaka (7.481, n=26, SD=0.458). The mean salivary pH of BMSR (8.098) and Tsimanampesotse (8.080, n=25, SD=0.746) ring-tailed lemurs did not differ significantly. Salivary pH for the Indianapolis Zoo sample (8.125, n=16, SD=0.289) did not differ significantly from either the BMSR or Tsimanampesotse ring-tailed lemurs, but was significantly more alkaline than the BMSR Verreaux's sifaka sample. Regardless of the time between feeding and collection of pH data (from several minutes to nearly 1 hr), salivary pH for each wild lemur was above the “critical” pH of 5.5, below which enamel demineralization occurs. Thus, the high pH of lemur saliva suggests a strong buffering capacity, indicating the impact of acidic foods on dental wear is short-lived, likely having a limited effect. However, tannins in tamarind fruit may increase friction between teeth, thereby increasing attrition and wear in lemurs. These data also suggest that salivary pH varies between lemur species, corresponding to broad dietary categories. Am. J. Primatol. 70:363–371, 2008. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Glucocorticoids, a group of adrenal hormones, are secreted in response to stress. In male primates, variables such as breeding seasonality, dominance hierarchy stability, and aggressive and affiliative interactions can affect glucocorticoid levels. In this study, we examined interindividual differences in mean fecal glucocorticoid (fGC) levels among males in three groups of wild ring-tailed lemurs to better understand the physiological costs of group living for males in a female-dominant species that exhibits strict reproductive seasonality. Fecal and behavioral data samples were collected during one mating and two postmating seasons (2001 and 2003). The mean fGC levels were examined in relation to reproductive season, male rank, number of resident males, intermale and female–male agonism, and affiliative behavior with females. The mean fGC levels were not significantly elevated during mating season compared to the postmating period. During the mating season, male dominance hierarchies broke down and rank effects could not be tested; however, there was no relationship between male rank and fGC levels in the postmating periods. In 2001, males that resided in the group with the fewest males exhibited lower fGC levels during the postmating period. They also affiliated more with females than did males in the other groups. During the mating season of 2003, males engaged in more affiliative behaviors with females compared to the postmating season, but female–male agonism did not differ by season. However, rates of intermale agonism were significantly higher during mating compared to postmating periods, but such heightened agonism did not translate to a higher stress response. Thus, neither male–male competition for mates nor heightened agonism between males during the breeding season affected male fGC levels. Fewer males residing in a group, however, did have some effect on male–female affiliation and male fGC levels outside of the mating period. Males that live in a group with only a few (two or three) males may experience less physiological stress than those that live in groups with more males. Am. J. Primatol. 67:5–23, 2005. © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Scent-marking and olfactory communication are used extensively by prosimians and can provide spatial and temporal records of group movement and behavior. We compare rates of male scent-marking in relation to reproductive seasons, male dominance rank, and habitat use in two related prosimians: Lemur catta and Eulemur fulvus rufus . We collected scent-marking data on adult male Lemur catta at Beza-Mahafaly Reserve (dry forest), and on Eulemur fulvus rufus at Ranomafana National Park (rainforest), Madagascar. In Lemur , rates of overall scent-marking differed significantly by reproductive season, with higher rates occurring in mating and lactation/migration periods, whereas in Eulemur , reproductive season did not appear to affect scent-marking rates. Dominance rank of male Lemur catta did not affect rates of scent-marking. Among male Eulemur fulvus , dominance relations were not apparent; however, 2 of the 5 focal males scent-marked somewhat more frequently during the mating season and also experienced greater mating success. In Lemur catta , higher rates of scent-marking in the mating season may relate to indirect reproductive competition during a period of high aggression, while such mating competition was not as marked in Eulemur fulvus . Furthermore, higher rates of marking in resident male Lemur catta during male migration may correlate with vigilance toward immigrating males. Greater overall scent-marking rates in ring-tailed lemurs may relate to extensive intergroup home range overlap and no area of exclusive use, whereas the red-fronted lemur groups tended to forage in areas of their home range where little-to-no intergroup overlap occurred. [ABSTRACT FROM AUTHOR]

We examine demographic patterns from a long-term study (1987–1996) of the population of ring-tailed lemurs in the Beza-Mahafaly Special Reserve, in southwestern Madagascar. In particular, we focus on the effects that a severe drought in 1991 and 1992 had on the population. The population of adult animals peaked in 1991 but decreased rapidly during the subsequent drought and immediate postdrought years. In the 1992 birth season (and second year of the drought) infant mortality reached 80%, and 20.8% of all adult females in the reserve died. The following year, adult female mortality reached a high of 29.9%. Juvenile mortality in 3 intensively studied groups was 57% during the second year of the drought. We compare these data with infant, juvenile, and adult female mortality in non-drought years. We are not able to calculate adult male mortality, as they often emigrate from the reserve to the adjacent forest; however, in the same 3 intensively studied groups, 89% of the males disappeared during the 2 immediate postdrought years. By 1996, the population had begun to recover after the decline that correlated with the drought conditions. Annual reproduction, high birth rates (.80–.86 annually), early sexual maturity, and dietary adaptability may be contributing factors to the recovery. Effects of and recovery from this type of natural disaster in the Beza Mahafaly ring-tailed lemur population parallel responses of some species of macaques and baboons with respect to the adaptability of edge species. [ABSTRACT FROM AUTHOR]

Examines the vigilance behavior of adult males and females in two groups of ring-tailed lemurs during the birth and lactation season at the Beza-Mahafaly Reserve in southwestern Madagascar. Rank of focal animals; Intrasexual rank and vigilance.

Affiliative behavior between adult male and female ringtailed lemurs was examined as part ora project concerning male affiliation with conspecifics of all age/sex classes. Males in three social groups were studied over a 12 month period. Male-female preferred partnerships existed, and were variable according to reproductive season. Dominance rank, age, or tenure of the male did not appear to affect either the number of partnerships or frequency of affiliative behaviors that males had with females. However, males residing m groups with fewer males exhibited both higher frequencies of affiliative interactions with females and were nearest neighbors to females more often than males living m a group containing more males. Females were found to be responsible for proximity maintenance of male-female dyads in the majority of cases. Neither reproductive season nor seasonal availability of food resources strongly affected the frequency of affiliative interactions between males and females, it is proposed that an important aspect of successful group membership for male ringtailed lemum relays to the development of social relationships with adult females. Males can benefit from such relationships in terms of greater centrality to the spatial core of the group, which can result in enhanced predator protection, greater opportunities for social contact, and potentially greater access to estrous females. [ABSTRACT FROM AUTHOR]

As with many other species in the primate order, ring-tailed lemurs (Lemur catta) are threatened with extinction. Our articles documented declines in wild ring-tailed lemur populations and noted that fewer than 2,500 wild ring-tailed lemurs are known to persist in 32 [Gould and Sauther: Primate Conservation 2016; 30: 89-101] and 34 [LaFleur et al.: Folia Primatologica 2017; 87: 320-330] sites. A criticism of our articles [Murphy et al.: International Journal of Primatology 2017; 38: 623-628] suggested that we have inadequately sampled ring-tailed lemur populations and habitats, and misused the literature. We disagree, and provide both a detailed rebuttal and responses to specific critique points herein. Moreover, we restate our case outlining a dramatic decline of ring-tailed lemurs resulting from anthropogenic pressures (deforestation, severe habitat fragmentation, extraction for the pet and bushmeat trades). We pose several thought-provoking questions as to when is the appropriate time for researchers to "sound the alarm" about a species' decline, and remain committed to understanding the drivers of unsustainable exploitation of this emblematic lemur, and preventing their extinction in the wild., (© 2018 S. Karger AG, Basel.)

Genetic variability among captive and wild ring-tailed lemurs (Lemur catta) was assessed using mitochondrial and nuclear DNA data. A 529 bp segment of mtDNA was sequenced and 9 microsatellite loci were genotyped for 286 ring-tailed lemurs. Samples were obtained from the well-studied L. catta population at the Bezà Mahafaly Special Reserve and from captive animals at six institutions worldwide. We found evidence of possible patrilineal contribution but the absence of matrilineal contribution from the Bezà area, and haplotypes not found in Bezà but present in Ambohimahavelona, Andringitra Massif, and other unknown locations, in the sampled captive population, indicating that the founders of the captive population originated from a wide geographic range. Total genetic variation and relatedness in captive L. catta in the six institutions were similar in extent to that of the wild population in Bezà. Based on the diverse origins of the captive population founders our results suggest the erosion of genetic diversity in the captive population. Sampled individuals from the same institution were more closely related to each other than members of a social group in the wild. Individuals housed at different institutions were less closely related than those of different social groups at Bezà, indicating lower genetic exchange between captive institutions than between social groups in a locality in the wild. Our findings underscore the usefulness of genotyping in determining the geographic origin of captive population founders, obtaining pedigree information if paternity is uncertain, and in maximizing preservation of extant genetic diversity in captivity., (© 2015 Wiley Periodicals, Inc.)

The spiny forest ecoregion of southern and southwestern Madagascar is characterized by low annual rainfall, high temperatures, short-stature xeric vegetation and lack of canopy. Lemur catta is often the only diurnal primate persisting in this habitat. For reproductive females living in spiny forests, gestation and early-to-mid lactation periods occur during the dry season when food resources are limited. We conducted a between-site comparison of variables important to the feeding ecology of reproductive female L. catta inhabiting spiny forest at 3 sites: Berenty spiny forest (BSF), Cap Sainte-Marie (CSM) and Tsimanampesotse National Park (TNP). We hypothesize that the ability for pregnant and lactating females to adequately obtain plant foods high in protein, low in fiber and with a high water content is crucial to their survival and successful reproduction in spiny habitat. We found favorable or relatively equal protein-to-fiber ratios in plant foods most frequently consumed by reproductive females, and preferred foods contained high water content. Some overlap in preferred plant species at the 3 sites suggests important plant foods for reproductive females inhabiting spiny forests. We suggest that choosing foods high in protein, relatively low in fiber and with high water content are behavioral adaptations allowing female L. catta to reproduce and survive in this habitat., (© 2015 S. Karger AG, Basel.)

Madagascar's lemurs, now deemed the most endangered group of mammals, represent the highest primate conservation priority in the world. Due to anthropogenic disturbances, an estimated 10% of Malagasy forest cover remains. The endangered Lemur catta is endemic to the southern regions of Madagascar and now occupies primarily fragmented forest habitats. We examined the influence of habitat fragmentation and isolation on the genetic diversity of L. catta across 3 different forest fragments in south-central Madagascar. Our analysis revealed moderate levels of genetic diversity. Genetic differentiation among the sites ranged from 0.05 to 0.11. These data suggest that the L. catta populations within south-central Madagascar have not yet lost significant genetic variation. However, due to ongoing anthropogenic threats faced by ring-tailed lemurs, continued conservation and research initiatives are imperative for long-term viability of the species., (© 2015 S. Karger AG, Basel.)

Lemur catta has traditionally been considered a species with male-biased dispersal; however, occasional female dispersal occurs. Using molecular data, we evaluated dispersal patterns in 2 L. catta populations in southwestern Madagascar: Tsimanampesotse National Park (TNP) and Bezà Mahafaly Special Reserve (BMSR). We also investigated the genetic differentiation between the populations and dispersal partner relatedness. Results showed minor genetic differentiation between the populations (ϴ(ST) = 0.039), which may indicate gene flow historically occurring in this region, made possible by the presence of L. catta groups between the sites. Different patterns of sex-biased dispersal were found between the sites using corrected assignment indices: male-biased dispersal in TNP, and a lack of sex-biased dispersal in BMSR. Observational evidence of female dispersal in BMSR supports these results and may imply intense female resource competition in and around BMSR, because small groups of 2-3 females have been observed dispersing within BMSR and entering the reserve from outside. These dispersing groups largely consisted of mothers transferring with daughters, although we have an aunt-niece pair transferring together. Genetic data suggest that males also transfer with relatives. Our data demonstrate that dispersal partners consist of same-sexed kin for L. catta males and females, highlighting the importance of kin selection., (© 2015 S. Karger AG, Basel.)

For over 50 years, ring-tailed lemurs have been studied continuously in the wild. As one of the most long-studied primate species, the length and breadth of their study is comparable to research on Japanese macaques, baboons and chimpanzees. They are also one of the most broadly observed of all primates, with comprehensive research conducted on their behaviour, biology, ecology, genetics, palaeobiology and life history. However, over the last decade, a new generation of lemur scholars, working in conjunction with researchers who have spent decades studying this species, have greatly enhanced our knowledge of ring-tailed lemurs. In addition, research on this species has expanded beyond traditional gallery forest habitats to now include high altitude, spiny thicket, rocky outcrop and anthropogenically disturbed coastal forest populations. The focus of this special volume is to 're-imagine' the 'flagship species of Madagascar', bringing together three generations of lemur scholars., (© 2015 S. Karger AG, Basel.)

Over 15 field seasons (1987-2001), we collected census and life-history data on a population of individually identified ring-tailed lemurs at the Beza Mahafaly Reserve, Madagascar. No significant difference was found in population size over the study period, though a marked decline in the population occurred following a 2-year drought. The population rebounded rapidly after the immediate postdrought period. There was nearly a complete replacement of individuals over the study period. Average group size is 11.5 animals, and adult male to female sex ratio is 0.92. Most females reproduce annually, and the average fecundity rate is 84.3%. The greatest variability in fecundity is found among old females. We suggest that ring-tailed lemur females follow an "income breeding" strategy, i.e., females use maximum resources during reproduction rather than relying on fat stores, as do "capital breeders." Infant mortality to 1 year of age in a nondrought year is 52%, higher than infant mortality in small to medium-sized anthropoids. The oldest known female was 18 years old in 2001. We suggest that 18-20 years may represent the maximum life-span for wild ring-tailed lemurs. Because males regularly emigrate from the population, we have no data regarding male life-span; however, there is some indication that males do not survive as long as females. Group fission has occurred three times: twice from one parent group living in the driest area of the reserve, with the most dispersed food resources. We suggest that the reproductive strategy that has evolved in this species, wherein females reproduce early in life and annually until old age, is a response to the unusual climate and environmental conditions under which Lemur catta has evolved., (Copyright 2003 Wiley-Liss, Inc.)