Anna T.C. Feistner

Preliminary Field Data on Group Size, Diet and Activity in the Alaotran Gentle Lemur Hapalemur griseus alaotrensis

The Alaotran gentle lemur Hapalemur griseus alaotrensis is a poorly known primate found in the reed and papyrus beds around Lac Alaotra, Madagascar. Because of its restricted distribution, which does not contain any protected areas, it was classified as of highest conservation priority in the Lemur Action Plan [1]. Little is known about this taxon, it having been studied only briefly in 1969 [2] and 1984 [3]. These studies were based on limited direct observation and most information was derived from interviews with local people. In order to find out more about the lemur, in particular what its conservation and population status really were, two field studies were carried out in the wet (March–April) and dry seasons (October–November) of 1993 [4, 5], followed by a 6month study from February to August 1994 [6]. Information on distribution, population size, conservation status [7, 8] and threats to H. griseus alaotrensis [9] has already been published. In this paper, we present information from the three studies on group size, diet and activity pattern.

Dietary Intake, Food Composition and Nutrient Intake in Wild and Captive Populations of Daubentonia madagascariensis

Data are presented on dietary and nutrient intake in a wild population of aye-ayes. Study animals ate 4 main food types: seeds, nectar, fungus and insect larvae. Calculated calorie intake was slightly lower during the cold season than during the hot, wet and the hot, dry seasons. Total intakes almost doubled to compensate for the lower energy content of the diet during the cold season. Comparison of natural and captive diets suggests that maintenance and even growth requirements of aye-ayes can be met by relatively low-fat, low-protein diets. Daily energy requirements were estimated to average about 280 kcal metabolizable energy/day. Animals in the wild were estimated to eat between 260 and 342 kcal, while captive animals consumed 260 kcal/day.

Conservation education in Madagascar: three case studies in the biologically diverse island-continent

Few Malagasy children and adults are aware of the rare and unique fauna and flora indigenous to their island‐continent, including flagship lemur species. Even the Malagasy ancestral proverbs never mentioned lemurs, but these same proverbs talked about the now extinct hippopotamus. Madagascars geography, history, and economic constraints contribute to severe biodiversity loss. Deforestation on Madagascar is reported to be over 100,000 ha/year, with only 10–15% of the island retaining natural forest [Green & Sussman, 1990]. Educating children, teacher‐training, and community projects about environmental and conservation efforts to protect the remaining natural habitats of endangered lemur species provide a basis for long‐term changes in attitudes and practices. Case studies of three conservation education projects located in different geographical regions of Madagascar, Centre ValBio, Madagacar Wildlife Conservation Alaotra Comic Book Project, and The Ako Book Project, are presented together with their ongoing stages of development, assessment, and outcomes. We argue that while nongovernmental organizational efforts are and will be very important, the Ministry of Education urgently needs to incorporate biodiversity education in the curriculum at all levels, from primary school to university. Am. J. Primatol. 72:391–406, 2010.

Conservation status and distribution of the Alaotran gentle lemur Hapalemur griseus alaotrensis

The Alaotran gentle lemur Hapalemur griseus alaotrensis is found only in the marsh vegetation surrounding Lac Alaotra in Madagascar. This habitat is shrinking and becoming fragmented due to conversion to rice cultivation. In addition, lemurs are hunted for pets and food. There is no protected area within their limited range. This paper presents the results of a 6-month field study assessing the distribution, population size and conservation status of the lemur. The population consists of about 7500 animals, split into at least two subpopulations. If no conservation action is taken in the near future, drainage of the remaining 13,000 ha block of marsh vegetation will probably lead to the extinction in the wild of this primate taxon .

Group encounters and territoriality in wild Alaotran gentle lemurs (Hapalemur griseus alaotrensis).

During a 3 month field study, 18 group encounters between four groups of Alaotran gentle lemurs (Hapalemur griseus alaotrensis) were observed in the Lake Alaotra marshland in Madagascar. Behaviors observed during group encounters are described, and quantitative data on intergroup interactions and ranging patterns are discussed in the context of territoriality. Intergroup interactions varied in their intensity, ranging from visual monitoring, scent marking, and display locomotion to penetrating the neighboring range. A quarter (27%) of the encounters were aggressive, involving chases and confrontation displays, and no affiliative interactions were observed. Both adult males and females were involved in intergroup encounters, with males playing more active roles. All encounters took place in the small overlapping areas of neighboring home ranges. The outcome of an aggressive encounter was determined by its location, with the resident group always driving out the intruding one. The Alaotran gentle lemur actively advertised and consistently defended a large area of its home range against intrusion of neighboring groups and can therefore be considered territorial. Am. J. Primatol. 46:251–258, 1998.

Food sharing in black lion tamarins (Leontopithecus chrysopygus)

Food sharing behavior was investigated by studying 10 captive black lion tamarin (Leontopithecus chrysopygus) infants (six litters) between the ages of four and 26 weeks. The frequency of sharing by parents in response to infant begging increased steadily from the age of five to nine weeks, but then declined gradually, although infants were still receiving food even at 26 weeks. Until the age of 15 weeks, infants received more food items by transfer from other group members than they did from self‐feeding. Thereafter, self‐feeding predominated. Offering of food by adults without prior infant begging occurred at low frequencies (5.3% of items transferred) and ceased at 20 weeks of age. Begging success (the proportion of infant begs which resulted in food sharing) remained relatively constant, averaging 65%. In common with other lion tamarins, black lion tamarins appear to continue to share food with infants well after weaning, and until at least six months of age. Am. J. Primatol. 52:47–54, 2000.

Social organization of the Alaotran gentle lemur (Hapalemur griseus alaotrensis)

Knowledge of the social organization of lemurs is still limited for most species. Where there is sufficient information, it has been shown that lemur social organization differs in essential points from that of other primates. In the field study reported here, demographic structure and life‐history processes were investigated in order to characterize the social organization of the Alaotran gentle lemur (Hapalemur griseus alaotrensis). Data were obtained through captures and observations. Alaotran gentle lemurs were found in small groups of up to nine individuals. Although most groups contained just one breeding female, a substantial proportion of groups (35%) had two breeding females. Therefore, Alaotran gentle lemurs cannot be classed as being organized in monogamous family groups. An extended birth season was found, and groups with two breeding females had significantly higher breeding output per adult than groups with a single adult female. Limited data suggest that females emigrate from their natal group while still subadult, whereas males can stay in the natal group until they are fully grown and disperse as adults. Variability in group composition, significantly higher reproductive output per adult in groups with two breeding females, and delayed dispersal of males suggest that Alaotran gentle lemurs pursue a resource‐defense mating strategy, rather than a female‐defense mating strategy. The suggestion that extant social lemurs may have evolved from a monogamous system, could explain the differences between lemur social systems and those of other primates. Am. J. Primatol. 50:9–24, 2000.

Responses of Captive Aye-Ayes (Daubentonia madagascariensis) to the Scent of Conspecifics: A Preliminary Investigation

The ability of 6 captive aye-ayes (Daubentonia madagascariensis) to discriminate scents from conspecifics of different age-sex classes was tested. The animals were presented with either unscented logs or logs that had been placed in: (1) their own cage, (2) the cages of adult males or (3) the cages of adult females with female offspring. Responses to the logs, measured by approaching, proximity, tapping, gnawing, sniffing, scent marking and vocalizations, were recorded for 30 min following presentation. Logs from females with offspring provoked the highest responses, and immature aye-ayes investigated logs more than adults of either sex. These results suggest that, as in many other prosimians, olfaction plays an important role in the communication systems of aye-ayes.

Food sharing in pied bare-faced tamarins (Saguinus bicolor bicolor): Development and individual differences

We investigated food sharing behavior in 5 litters of pied bare-faced tamarins (Saguinus bicolor bicolor)—8 infants, from 3 families—from 5 to 26 weeks of age. The frequency of sharing by parents in response to infant begging increased steadily from the age of 5 weeks to 16 weeks, and then declined. Offering of food by adults without prior infant begging occurred at very low frequencies throughout observations (1.5% of total items transferred). On average, infants received approximately equal amounts of food from transfers from others and by self feeding until about 20 weeks, after which self feeding began to predominate. Begging success—the proportion of infant begs which resulted in food sharing—remained relatively constant over time, at 60–70%. Overall, therefore, the frequency of food sharing seemed to be governed by changes in infant rather than adult behavior. There were individual differences between adults in their response to infant begging, but two of three fathers transferred significantly more food to infants than mothers did. The results of this study emphasize the existence of specific and individual differences in food-sharing behavior, which must be taken into account in explaining its importance in the reproductive strategies of the Callitrichidae.

Cross-generic Food Sharing in Tamarins

Adult-infant food-sharing behavior is a major component of the infant care strategies of callitrichids (marmosets and tamarins). It is particularly well-developed in cotton-top tamarins (Saguinus Oedipus) and lion tamarins (Leontopithecus spp), which show frequent adult-initiated food offering, as well as sharing of food in response to begging by infants. This report documents a case of cross-generic food sharing, in which a male golden-headed lion tamarin (Leontopithecus chrysomelas) shared food with an infant cotton-top tamarin. The lion tamarin provided more food to the infant than its mother did. This emphasizes the importance of this behavior in the reproductive strategies of the communally-rearing Callitrichidae and raises questions about mechanisms that underly it.