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MN265 Spatial Ecology, Behaviour and Responses to Anthropogenic Disturbance of Lemurs in Mahamavo Dry Forests, Madagsacar Prof. Dr. Ute Radespiel, TiHo Hanover/Germany Dr. Kathy Slater, Operation Wallacea Within the Mahamavo forests of Western Madagascar there are numerous opportunities to study the species of lemur that occur there. The research opportunities can broadly be divided into two areas that focus on (1) the effect of anthropogenic habitat disturbance and human settlements on lemur ecology and behaviour and (2) the spatial ecology and feeding behaviour of Coqeuerel's Sifaka. Students booking on to this research project will be able to design their proposal around either of these two lines of enquiry based on the project summaries below. Study Site The project will be conducted in the Mahamavo area in northwestern Madagascar, close to the village of Mariarano. The habitat in this area is a matrix of wetlands and dry forest. The dry deciduous forest fragments of the area vary in size and surround the camp sites (Figure 1). Up to eight lemur species can be found in the fragments but their spatial distribution and local abundance in the fragments may vary. Various forest trails and a systematic grid system in the area allow access to the forest and will be used for systematic data collection. a) forest / non-forest b) patch area Figure 1: Maps of Mahamavo protected area showing forest patches in terms of forest versus nonforest (a) and forest patch area (b). Forest patch area was calculated using the distance of every forested pixel from the forest edge, the perimeter:area ratio of every forest patch (a measure of compactness), and the distance to the edge of the nearest neighbouring forest patch (a measure of isolation). Both maps were prepared by Dr Peter Long from Oxford University. 1) The effect of anthropogenic habitat disturbance and human settlements on lemur ecology and behaviour, Madagascar The high level of deforestation that has occurred on Madagascar over the past century is a primary conservation concern. The constant loss of forest habitats coincides with an increasing degree of forest fragmentation, and the rather small geographic distributions of many lemur species. In addition, remaining forests are often altered by selective logging or wood extraction, and many lemur species are still locally hunted (Mittermeier et al. 2010). In this situation it is of utmost importance to understand the ecological plasticity and responses of each lemur species towards these anthropogenic threats. This knowledge is needed to understand the ecological vulnerability of each species and to develop and formulate expert recommendations for effective conservation measures. It is known that anthropogenic disturbances such as habitat fragmentation, selective logging or hunting can modify habitats and alter the community structure and behavioural ecology of free-living animal populations considerably (Henle et al. 2004). However, it is also known that not all lemur species respond equally to forest fragmentation (Lehman et al. 2006). Extant Malagasy lemurs have very diverse ecological requirements (microhabitats, sleeping sites etc.), activity patterns (nocturnal, diurnal, cathemeral), feeding habits (folivores, frugivores, omnivores), body sizes (40g - 9.5kg) and social organisations, and the interactions between these parameters and the long-term viability of lemur populations in fragments is still largely underexplored. The intensity of habitat disturbances typically correlates with the access of humans to an area. Spatial proximity to the next human settlements and to forest edges can be a good approximation for these potential threats. A total of eight lemur species are known from the Mariarano area, six of which are nocturnal (Microcebus murinus, M. ravelobensis, Cheirogaleus medius, Phaner pallescens, Lepilemur edwardsi, Avahi occidentalis) and two are diurnal or partly cathemeral species (Eulemur fulvus, Propithecus coquereli) (Olivieri et al. 2005, Mittermeier et al. 2010). Five of them are categorized as endangered since the most recent IUCN assessment (IUCN 2012). The eight species vary in all above mentioned traits and therefore form an interesting subset of species to explore the effects of habitat fragmentation on species with different life styles and life histories. Species can be expected to alter their ecology but also their behaviour in response to human interventions of various kinds. For example, individuals may show different feeding strategies or group sizes, or they may differ in locomotion, vigilance, or flight responses towards human observers in varying distances to forest edges and settlements. The aim of this study is to explore the influence of varying proximity to human settlements and forest edges on the abundance and behaviour of different lemur species occurring in the Mahamavo region of northwestern Madagascar. Particular emphasis shall be given to nocturnal species (Microcebus spp., Lepilemur edwardsi), as they are generally less studied than their diurnal cousins but not necessarily less vulnerable. Data Collection Data on the spatial distribution of lemurs species are typically collected with nocturnal or diurnal very slow survey walks (Durckworth 1998) which need to be complemented with capture-mark-release sessions in the case of mouse lemurs (Microcebus spp.), since the two sympatric species cannot be easily distinguished during nocturnal surveys (Rakotondravony & Radespiel, 2009). During a systematic survey walk, lemur encounters are always documented for each species by with a GPS-device, and complementary data can be simultaneously collected on the used microhabitats (e.g. substrate, height above ground), group size, and/or behaviour (e.g. locomotion, feeding, flight response) that will allow the test of specific hypotheses. Each survey walk will take between 2-3 hours depending on trail length (1-1.5km) which should have a perpendicular orientation to the forest edge. The remaining time of the day can then be used for data entry and analyses of the GIS-based dataset and edgedependent behavioural responses. Mouse lemur capture sessions are typically performed overnight with the help of Sherman Live Traps that are baited with banana and checked in the early morning. The installation of traps at varying distance from forest edges and human settlements will allow testing the influence of these two parameters on mouse lemur abundance. Captured mouse lemurs will be marked, sexed, and assigned to their respective species. They can furthermore be measured morphometrically in order to obtain physical data on body size, body dimension or body condition that may be relevant for certain questions. All mouse lemurs will be released at their individual capture sites at dusk. Capture data will allow to determine species-specific abundances and edge responses of both species in a comparable way. Survey walks can also be combined with the method of focal animal sampling (Altmann 1974) in order to obtain more extended behavioural datasets for a particular lemur species. Encountered but individually unknown individuals of that species can be followed and observed continuously until contact is lost. The interrupted survey walk will subsequently be resumed up to the next encounter, which will mark the beginning of the next episode of behavioural observations. By employing this mixed approach, larger behavioural datasets can be obtained without actually marking the animals or knowing them individually. These modified survey walks will typically be conducted over half nights or half days. Mouse lemurs (Microcebus spp.) can also be observed individually by employing the method of radio-tracking which is always preceded by a period of capturing. Some captured individuals can then be radio-collared and will subsequently be released at their respective capture sites. The observer can then collect individual-based datasets on a defined number of individuals on space use (home range sizes), sleeping sites, or other behaviours in varying distance from forest edges and human settlements. Nocturnal focal observations will typically be conducted over half nights. Depending on the topic that is chosen and developed within this framework of fragmentation effects, some of the above mentioned methods can be combined and conducted in parallel in study sites that differ in their proximity to forest edges and human settlements. 2) Feeding ecology, habitat preferences and activity budgets of Coquerel’s Sifaka, Madagascar Coquerel’s Sifaka (Propithecus coquereli) is a medium sized lemur with a total length of 93110cm and weight of 3.7-4.3kg (Rambinintsoa et al., 2006). They are diurnal and live in extended family groups of 2-10 individuals (Rambinintsoa et al., 2006; Mittermeier et al., 2010). This species is primarily folivorous, but are also known to eat flowers and fruits when available (Richard, 1978; Mittermeier et al., 2010). Their diet includes up to 98 different plant species (Richard, 1978), but they show a significant preference for leaves high in extractable protein and low in acid detergent fibre (Ganzhorn, 1992). These “high quality” leaves occur at significantly higher densities in dry deciduous forest than in evergreen forest (Ganzhorn, 1992). Feeding is often in a suspensory posture (Mittermeier et al., 2010). Coquerel’s Sifakas are most active in the morning and late afternoon, and travel between trees by leaping often large distances from trunk to trunk and occasional bipedal hopping similar to a kangaroo (Mittermeier et al., 2010). They favour gallery forest, but can be found in a range of habitats including degraded forests and small forest fragments (Mittermeier et al., 2010). However, detailed studies of their behavioural and dietary adaptations to forest fragmentation and degradation are lacking. Coquerel’s Sifaka have one of the most restricted ranges of all the lemurs and are only found in the lowland dry forests of north western Madagascar. Listed as an IUCN endangered species, these lemurs are severely threatened by habitat loss and hunting. For local tribes in the region it is taboo to harm the lemurs, but recent immigration had lead to hunting of Coquerel’s Sifaka in some areas. There are only two protected areas where Coquerel’s Sifaka are known to occur: the Ankarafantsika National Park and the Bora Special Reserve. Unfortunately there is significant hunting pressure on this species in Ankarafantsika and the forest in Bora has become considerably degraded. Coquerel’s Sifaka are also found in forests outside these protected areas. Community based conservation projects in these areas are therefore extremely important for the survival of this species. The aim of this project is to investigate the ranging, habitat preferences, feeding ecology, and activity budgets of Coquerel’s Sifaka in the Mahamavo region of north western Madagascar, close to the village of Mariarano. These data will provide vital information relating to the species behavioural and dietary adaptations when living in forest fragments. The data will also be useful for the community management of the area by improving the understanding of the ecological needs and impacts of habitat disturbance on Coquerel’s Sifaka. Data Collection In order to investigate activity budgets, data is needed from dawn until dusk. However, such long days does not leave sufficient time for data entry and addition data collection such as habitat assessments. Depending on the ease with which the lemurs can be encountered and the length of time they can be followed each day, behavioural observations will either be conducted from dawn until dusk with occasional full days where the lemurs are not observed to allow time for data entry and other data collection, or in morning (dawn till midday) and afternoon sessions (midday till dusk) leaving half-day sessions for data entry and other data collection. The GPS location of the group will be recorded throughout the day in order to assess home and day range. Upon locating a group, the number or individuals and age-sex classification of each will be recorded. Activity data will be collected using instantaneous scan samples (Altmann 1974). You will need to decide on the interval for these scans, either 3, 5, or 10 minute intervals. If you can easily scan the group and record data for each individual within 1 minute, then 3 minute intervals are fine, but if it takes you longer to do this (due to visibility issues or because group members are often spread out) then you need to increase the interval to 5 or 10 minutes to ensure that each scan is independent of the other. For each scan you should record the behaviour (feeding, moving, resting, social, vigilant etc) of each adult individual in the group using a predefined behavioural ethogram. When feeding, the type of food (mature leaves, young leaves, fruit, flowers and bark), and corresponding plant species will be recorded where known. Where plants can not be identified in the field, photographs and samples will be taken for later identification. For each scan, the habitat type, predominant plant species, and weather conditions can be recorded. Additional data can then be collected in order to interpret the findings of the activity and diet data. Habitat surveys could be conducted to investigate forest structure, woody plant composition and to ascertain the level of forest disturbance. Habitat data could be collected using 20m x 20m plots in which the major woody plants are identified, DBH is measured, canopy cover is measured using canopy scopes and evidence of anthropogenic disturbance is recorded. Alternatively, habitat preferences could be investigated by uploaded ranging patterns of the lemurs obtained from GPS units onto existing GIS vegetation maps of the reserve. It may also be possible to investigate how Sifakas adapt their behaviour and diet according to characteristics of the forest fragments in terms of patch area and distance to other fragments. References Altmann, J. 1974. Observational study of behaviour: sampling methods. Behaviour 49: 227267. Duckworth. J.W. 1998. The difficulty of estimating population densities of nocturnal forest mammals from transect counts of animals. Journal of Zoology, London 246: 466-468. Ganzhorn, J. U. (1992). Leaf chemistry and the biomass of folivorous primates in tropical forests. Test of a hypothesis. Oecologia 91: 540–547. Henle, K., Davies, K.F., Kleyer, M., Margules, C., Settele, J. 2004. Predictors of species sensitivity to fragmentation. Biodiversity and Conservation 1: 207-251. Lehman S.M., Rajaonson, A. & Day, S. 2006. Edge effects and their influence on lemur density and distribution in southeast Madagascar. American Journal of Physical Anthropology 129: 232-241. Mittermeier, R.A., Louis Jr, E.E., Richardson, M., Schwitzer, C., Langrand, O. Rylands, A.B., Hawkins, F., Rajaobelina, S., Ratsimbazafy, J., Rasoloarison, R., Roos, C., Kappeler, P.M. and Mackinnon, J., Illustrated by Nash, S.D. (2010). Lemurs of Madagascar: Conservation International Tropical Field Guide Series, Third Edition. Conservation International: Arlington, VA, USA. Olivieri, G., Craul, M. & Radespiel, U. 2005. Inventaire des lémuriens dans 15 fragments de forêt de la province de Mahajanga. Lemur News 10: 11-16. Rakotondravony, R. & Radespiel, U. 2009. Varying patterns of coexistence of two mouse lemur species (Microcebus ravelobensis and M. murinus) in a heterogeneous landscape. American Journal of Primatology 71: 928-938. Rambinintsoa, A., Rigobert, Z.J., Richar, R., Razafindraibe Jean François Xavier, R.J.F., Brenneman, R.A. and Edward E. Louis Jr, E.E. (2006). A preliminary study on resident lemur populations in the Mariarano Classified Forest. Lemur News 11: 21-24 Richard, A.F. (1978). Behavioral Variation: Case Study of a Malagasy Lemur. Bucknell University Press: London.