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Over the past 20 years, GPS collars have emerged as powerful tools for the study of nonhuman primate (hereafter, "primate") movement ecology. As the size and cost of GPS collars have decreased and performance has improved, it is timely to review the use and success of GPS collar deployments on primates to date. Here we compile data on deployments and performance of GPS collars by brand and examine how these relate to characteristics of the primate species and field contexts in which they were deployed. The compiled results of 179 GPS collar deployments across 17 species by 16 research teams show these technologies can provide advantages, particularly in adding to the quality, quantity, and temporal span of data collection. However, aspects of this technology still require substantial improvement in order to make deployment on many primate species pragmatic economically. In particular, current limitations regarding battery lifespan relative to collar weight, the efficacy of remote drop-off mechanisms, and the ability to remotely retrieve data need to be addressed before the technology is likely to be widely adopted. Moreover, despite the increasing utility of GPS collars in the field, they remain substantially more expensive than VHF collars and tracking via handheld GPS units, and cost considerations of GPS collars may limit sample sizes and thereby the strength of inferences. Still, the overall high quality and quantity of data obtained, combined with the reduced need for on-the-ground tracking by field personnel, may help defray the high equipment cost. We argue that primatologists armed with the information in this review have much to gain from the recent, substantial improvements in GPS collar technology.

Drilling time and resources for casing and cementing the wellbore represent a significant cost in oilwell construction. Due to that, slender wells have been targeted to be constructed with less phases and higher efficiency reducing costs by half. The objective of this paper is to present how a fit-for-purpose foam cement system contributed to deliver a dependable barrier for a True One Trip Ultra-Slender well, where a single barrier shall provide wellbore mechanical integrity and competent isolation from the reservoir to seabed. The methodology for the foam cement job discussed in this paper involved, at first, hydraulic and thermal modelling, followed by extensive lab tests, such as thickening time, compressive strength and foam stability tests. The pumping schedule, included 4 different tailored systems that were pumped to maximize probability of returns at the mudline. By using the constant-nitrogen-rate technique, the foam quality was optimized to help ensure slurry and foam stability at bottomhole conditions. Proper energized fluid selection and casing centralization were placed to guarantee a slurry system application with improved mud removal capacity and optimized standoff to avoid slurry contamination attributed to channeling. During execution, no issues were observed until reaching the final depth. The open hole diameter was estimated by pumping a tracer and a sacrificial slurry, to be visualized at the mudline. With that information, further volumes were tuned and pumped to ensure appropriate foam cement quality and density along the wellbore. As one of the major objectives of the job, returns could be achieved at mudline and the final differential pressure was higher than expected, indicating a cement sheath in the annulus had extensive length. The cement job evaluation was performed after the job using sonic and ultrasonic tools to confirm the quality of the barrier placed in the annulus. Additionally, an Advanced Cement Evaluation was executed and showed excellent isolation for the slurries placed in the well. The results from this unprecedented operation in Brazil has proven the features and benefits of using foam cement in ultra-slender wells for specific challenges, such as: requirement of returns at mudline, application in long length zonal isolation operations and the necessity of high strength low density solutions. After this job, similar wells have been constructed in the same area, and the applied technique has continuously proven to be a dependable and sound solution for similar scenarios. Based on the successful case history presented in this paper, the application of foam cement technology in ultra-slender wells represent an innovative and dependable solution for the actual and future high efficiency wellbore geometries. By reducing the risks of having a single cement sheath in the entire well, it enables oilwell industry to reduce time and risks during wellbore construction and helps enhance its productivity.

Among mammals, the order Primates is exceptional in having a high taxonomic richness in which the taxa are arboreal, semiterrestrial, or terrestrial. Although habitual terrestriality is pervasive among the apes and African and Asian monkeys (catarrhines), it is largely absent among monkeys of the Americas (platyrrhines), as well as galagos, lemurs, and lorises (strepsirrhines), which are mostly arboreal. Numerous ecological drivers and species-specific factors are suggested to set the conditions for an evolutionary shift from arboreality to terrestriality, and current environmental conditions may provide analogous scenarios to those transitional periods. Therefore, we investigated predominantly arboreal, diurnal primate genera from the Americas and Madagascar that lack fully terrestrial taxa, to determine whether ecological drivers (habitat canopy cover, predation risk, maximum temperature, precipitation, primate species richness, human population density, and distance to roads) or species-specific traits (body mass, group size, and degree of frugivory) associate with increased terrestriality. We collated 150,961 observation hours across 2,227 months from 47 species at 20 sites in Madagascar and 48 sites in the Americas. Multiple factors were associated with ground use in these otherwise arboreal species, including increased temperature, a decrease in canopy cover, a dietary shift away from frugivory, and larger group size. These factors mostly explain intraspecific differences in terrestriality. As humanity modifies habitats and causes climate change, our results suggest that species already inhabiting hot, sparsely canopied sites, and exhibiting more generalized diets, are more likely to shift toward greater ground use.

Accurately quantifying species’ area requirements is a prerequisite for effective area‐based conservation. This typically involves collecting tracking data on species of interest and then conducting home‐range analyses. Problematically, autocorrelation in tracking data can result in space needs being severely underestimated. Based on the previous work, we hypothesized the magnitude of underestimation varies with body mass, a relationship that could have serious conservation implications. To evaluate this hypothesis for terrestrial mammals, we estimated home‐range areas with global positioning system (GPS) locations from 757 individuals across 61 globally distributed mammalian species with body masses ranging from 0.4 to 4000 kg. We then applied block cross‐validation to quantify bias in empirical home‐range estimates. Area requirements of mammals 1, meaning the scaling of the relationship changed substantially at the upper end of the mass spectrum., Article impact statement: Due to autocorrelation‐induced bias, conventional methods severely underestimate the area requirements of GPS‐tracked large mammals.

The intestinal microbiota plays a major role in host development, metabolism, and health. To date, few longitudinal studies have investigated the causes and consequences of microbiota variation in wildlife, although such studies provide a comparative context for interpreting the adaptive significance of findings from studies on humans or captive animals. Here, we investigate the impact of seasonality, diet, group membership, sex, age, and reproductive state on gut microbiota composition in a wild population of group‐living, frugi‐folivorous primates, Verreaux's sifakas (Propithecus verreauxi). We repeatedly sampled 32 individually recognizable animals from eight adjacent groups over the course of two different climatic seasons. We used high‐throughput sequencing of the 16S rRNA gene to determine the microbiota composition of 187 fecal samples. We demonstrate a clear pattern of seasonal variation in the intestinal microbiota, especially affecting the Firmicutes‐Bacteroidetes ratio, which may be driven by seasonal differences in diet. The relative abundances of certain polysaccharide‐fermenting taxa, for example, Lachnospiraceae, were correlated with fruit and fiber consumption. Additionally, group membership influenced microbiota composition independent of season, but further studies are needed to determine whether this pattern is driven by group divergences in diet, social contacts, or genetic factors. In accordance with findings in other wild mammals and primates with seasonally fluctuating food availability, we demonstrate seasonal variation in the microbiota of wild Verreaux's sifakas, which may be driven by food availability. This study adds to mounting evidence that variation in the intestinal microbiota may play an important role in the ability of primates to cope with seasonal variation in food availability.

Group size is a key component of sociality and can affect individual health and fitness. However, proximate links explaining this relationship remain poorly understood, partly because previous studies neglected potential confounding effects of ecological factors. Here, we correlated group size with various measures of health while controlling for measures of seasonality and habitat quality, to explore trade-offs related to group living in a mainly folivorous primate—Verreaux’s sifakas (Propithecus verreauxi). Over a course of 2 years, we studied 42 individuals of 7 differently sized groups (range 2–10) and combined measures of faecal glucocorticoid metabolites (n > 2300 samples), parasitism (n > 500 samples), ranging and activity patterns, together with estimates of habitat quality (measures of ~ 7000 feeding trees). None of our measures was correlated with group size, while seasonality, but not habitat quality, impacted almost all examined variables. We conclude that group size alone might be insufficient to explain patterns in the sociality-health nexus or that the small range of group sizes in this species does not induce effects suggested for species living in larger groups. An optimal group size balancing the advantages and disadvantages of living in differently sized groups may not exist for Verreaux’s sifakas. Our results do not support predictions of the ecological constraints hypothesis or the optimal group size hypothesis as they may only account for species limited in group size by ecological factors—a condition that may not apply to the majority of folivorous mammals, which seem to be limited by social factors. Group size is a key component of group living and can crucially impact individual health. Ecological variables may modulate this relationship, but they were often neglected in previous studies. To better understand the links between sociality and health, we, for the first time in a mammal, simultaneously examined variation in ranging patterns, daily activities, glucocorticoid concentrations, and parasitism as a function of group size and under consideration of measures of seasonality and habitat quality in wild Verreaux’s sifakas (Propithecus verreauxi). Group size had no impact on individual health indicators, while seasonal variation in food availability and temperature differences, but not habitat quality, affected the majority of variables. We demonstrate strong impacts of environmental factors on socio-ecological traits and conclude that group size on its own might be insufficient to explain patterns in the sociality-health nexus.

Individuals living in groups have to achieve collective action for successful territorial defense. Because conflicts between neighboring groups always involve risks and costs, individuals must base their decision to participate in a given conflict on an evaluation of the trade-off between potential costs and benefits. Since group members may differ in motivation to engage in group encounters, they exhibit different levels of participation in conflicts. In this study, we investigated factors influencing participation in intergroup encounters in Verreaux's sifakas (Propithecus verreauxi), a group-living primate from Madagascar. Over a period of 12 months, we studied eight adjacent sifaka groups in Kirindy Forest. We observed 71 encounters between known neighboring groups in which adult females and males participated equally as often. No individual participated in every encounter, and non-participation occurred more often in larger groups. Females participated less often in encounters when they had dependent infants, presumably to reduce the risk of infanticide. Male participation was influenced by social status: dominant males participated in most encounters, whereas males with fewer opportunities to reproduce participated less often, hence male participation is influenced by the incentive of maintaining access to females. The number of actively participating individuals in the opponent group positively influenced the participation in both sexes. Thus, sifakas seem to decide joining a given encounter opportunistically, most likely based on a combination of individual incentives and the actual circumstance of each encounter, suggesting that the complexity in intergroup relationships appears to be the product of decisions made by each individual group member. SIGNIFICANCE STATEMENT: Cooperation among group-living animals is often challenged by collective action problems resulting from individual differences in interests in contributing to collective behaviors. Intergroup encounters involve distinguished costs and benefits for each individual despite being in the same social group. Therefore, encounters between groups offer a good opportunity to investigate individual participation in collective action. In this study, we investigate the influence of different incentives on individual participation in intergroup encounters in wild Malagasy primate, Verreaux's sifakas. We propose a novel approach that takes into account the variable circumstances of each conflict, such as the number of individuals fighting in both groups as a predictor for participation. We believe that our study not only provides novel data on wild sifakas, but it also offers new perspectives for the interpretation of intergroup relationships in other taxa. peerReviewed

Over the past 20 years, GPS collars have emerged as powerful tools for the study of nonhuman primate (hereafter, “primate”) movement ecology. As the size and cost of GPS collars have decreased and performance has improved, it is timely to review the use and success of GPS collar deployments on primates to date. Here we compile data on deployments and performance of GPS collars by brand and examine how these relate to characteristics of the primate species and field contexts in which they were deployed. The compiled results of 179 GPS collar deployments across 17 species by 16 research teams show these technologies can provide advantages, particularly in adding to the quality, quantity, and temporal span of data collection. However, aspects of this technology still require substantial improvement in order to make deployment on many primate species pragmatic economically. In particular, current limitations regarding battery lifespan relative to collar weight, the efficacy of remote drop-off mechanisms, and the ability to remotely retrieve data need to be addressed before the technology is likely to be widely adopted. Moreover, despite the increasing utility of GPS collars in the field, they remain substantially more expensive than VHF collars and tracking via handheld GPS units, and cost considerations of GPS collars may limit sample sizes and thereby the strength of inferences. Still, the overall high quality and quantity of data obtained, combined with the reduced need for on-the-ground tracking by field personnel, may help defray the high equipment cost. We argue that primatologists armed with the information in this review have much to gain from the recent, substantial improvements in GPS collar technology.

Made available in DSpace on 2018-11-26T17:44:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2018-01-26 Robert Bosch Foundation Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission. Senckenberg Gesell Naturforsch, Senckenberg Biodivers & Climate Res Ctr, D-60325 Frankfurt, Main, Germany Goethe Univ, Dept Biol Sci, D-60438 Frankfurt, Main, Germany Univ Maryland, Dept Biol, College Pk, MD 20742 USA Univ Maryland, SESYNC, Annapolis, MD 21401 USA Univ Guelph, Dept Integrat Biol, Guelph, ON N1G 2W1, Canada Norwegian Inst Nat Res, POB 5685 Torgard, NO-7485 Trondheim, Norway Duke Univ, Dept Biol, Durham, NC 27708 USA Duke Univ, Dept Evolut Anthropol, Durham, NC 27708 USA Hirola Conservat Programme, Garissa, Kenya Swedish Univ Agr Sci, Dept Wildlife Fish & Environm Studies, S-90183 Umea, Sweden Radboud Univ Nijmegen, Dept Anim Ecol & Physiol, Inst Water & Wetland Res, NL-6500 GL Nijmegen, Netherlands Univ Fed Mato Grosso do Sul, Ecol & Conservat Grad Program, Campo Grande, MS, Brazil Univ Alberta, Dept Biol Sci, Edmonton, AB, Canada Univ London, Royal Vet Coll, Struct & Motion Lab, London NW1 0TU, England Wildlife Conservat Soc, Mongolia Program, Ulaanbaatar, Mongol Peo Rep Mississippi State Univ, Forest & Wildlife Res Ctr, Carnivore Ecol Lab, Box 9690, Mississippi State, MS USA Sao Paulo State Univ, Anim Biol Postgra Program, BR-15054000 Sao Jose Do Rio Preto, SP, Brazil Michigan Dept Nat Resources, 1990 US 41 South, Marquette, MI 49855 USA Univ Calif Davis, Dept Anthropol, Davis, CA 95616 USA Aarhus Univ, Dept Biosci, DK-4000 Roskilde, Denmark Max Planck Inst Ornithol, Vogelwarte Radolfzell, D-78315 Radolfzell am Bodensee, Germany Wildlife Conservat Soc, Bronx, NY 10460 USA Univ Potsdam, Plant Ecol & Nat Conservat, D-14476 Potsdam, Germany Middle Tennessee State Univ, Dept Biol, Murfreesboro, TN 37132 USA Univ Pretoria, Dept Zool & Entomol, Mammal Res Inst, ZA-0028 Gauteng, South Africa Fdn Edmund Mach, Res & Innovat Ctr, Dept Biodivers & Mol Ecol, I-38010 San Michele All Adige, TN, Italy Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA Natl Zool Pk, Smithsonian Conservat Biol Inst, Front Royal, VA USA Univ Evora, Depat Fitotecn, P-7002554 Evora, Portugal Univ Evora, ICAAM, Inst Mediterranean Agr & Environm Sci, Evora, Portugal Univ Montpellier, Univ Paul Valery Montpellier, CNRS,EPHE, Ctr Ecol Fonctionnelle & Evolut,UMR 5175, F-34293 Montpellier 5, France Phillip Isl Nat Parks, Cowes, Vic, Australia Monash Univ, Sch Biol Sci, Melbourne, Vic, Australia Ohio State Univ, Dept Civil Environm & Geodet Engn, Columbus, OH 43210 USA Fiji Natl Univ, Dept Biol, POB 5529, Natabua, Lautoka, Fiji Univ Massachusetts, US Geol Survey, Massachusetts Cooperat Fish & Wildlife Res Unit, Amherst, MA 01003 USA Penn State Univ, US Geol Survey, Penn Cooperat Fish & Wildlife Res Unit, University Pk, PA 16802 USA Univ Oxford, Dept Zool, Oxford OX1 3PS, England Giraffe Conservat Fdn, POB 86099, Eros, Namibia German Primate Ctr, Behav Ecol & Sociobiol Unit, D-37077 Gottingen, Germany Tech Univ Munich, Dept Ecol & Ecosyst Management, Restorat Ecol, D-85354 Freising Weihenstephan, Germany Cary Inst Ecosyst Studies, Millbrook, NY 12545 USA Univ British Columbia, Irving K Barber Sch Arts & Sci, Unit 2, Biol, Okanagan Campus, Kelowna, BC V1V 1V7, Canada Univ Zurich, Dept Evolutionary Biol & Environm Studies, CH-8057 Zurich, Switzerland Univ Wyoming, Dept Zool & Physiol, Laramie, WY 82071 USA Univ Washington, Sch Environm & Forest Sci, Seattle, WA 98195 USA Univ Montana, Coll Forestry & Conservat, Dept Ecosyst & Conservat Sci, Wildlife Biol Program, Missoula, MT 59812 USA Bavarian Forest Natl Pk, Dept Conservat & Res, D-94481 Grafenau, Germany Albert Ludwigs Univ Freiburg, Wildlife Ecol & Management, D-79106 Freiburg, Germany Univ Toulouse, INRA, CEFS, Castanet Tolosan, France Univ Calif Davis, Anim Behav Grad Grp, Davis, CA 95616 USA Bionet Natr Onderzoek, NL-6171 EL Stein, Netherlands Univ Vet Med Vienna, Res Inst Wildlife Ecol, A-1160 Vienna, Austria Univ Coll Cork, Sch Biol Earth & Environm Sci, Cork, Ireland Univ Wyoming, US Geol Survey, Dept Zool & Physiol, Wyoming Cooperat Fish & Wildlife Res Unit, Laramie, WY USA North Carolina Museum Nat Sci, Raleigh, NC 27601 USA North Carolina State Univ, Dept Forestry & Environm Resources, Raleigh, NC 27695 USA Karatina Univ, Dept Nat Resource Management, POB 195710101, Karatina, Kenya Univ Lethbridge, Dept Psychol, Lethbridge, AB T1K 3M4, Canada Columbia Univ, Lamont Doherty Earth Observ, Palisades, NY 10964 USA Univ Valencia, Terr Vertebrates Grp, Cavanilles Inst Biodivers & Evolutionary Biol, E-46980 Valencia, Spain SUNY Stony Brook, Dept Anthropol, Stony Brook, NY 11794 USA TSG, SSC, IUCN, Rua Licuala 622,Damha 1,Campo Grande, BR-79046150 Mato Grosso Sul, Brazil IPE Inst Pesquisas Ecol Inst Ecol Res, Caixa Postal 47, BR-12960000 Sao Paulo, Brazil Univ Alicante, Dept Ciencias Ambient & Recursos Natur, Vertebrates Zool Res Grp, Alicante, Spain Embrapa Pantanal, BR-79320900 Corumba, MS, Brazil Chico Mendes Inst Conservat Biodivers, Natl Res Ctr Carnivores Conservat, BR-12952011 Atiba, SP, Brazil Univ Glasgow, Inst Biodivers Anim Hlth & Comparat Med, Glasgow, Lanark, Scotland NYU, Dept Biol, Ctr Genom & Syst Biol, New York, NY 10003 USA Univ Calif Davis, Dept Microbiol & Mol Genet, Davis, CA 95616 USA Univ Oslo, Dept Biosci, Ctr Ecol & Evolutionary Synth, NO-0316 Oslo, Norway Hebrew Univ Jerusalem, Alexander Silberman Inst Life Sci, Dept Ecol Evolut & Behav, Movement Ecol Lab, IL-91904 Jerusalem, Israel Norwegian Inst Nat Res, NO-0349 Oslo, Norway Norwegian Univ Sci & Technol NTNU, Dept Math Sci & Ctr Biodivers Dynam, N-7491 Trondheim, Norway Univ Fed Mato Grosso do Sul, Dept Ecol, BR-79070900 Campo Grande, MS, Brazil Field Museum Nat Hist, Integrat Res Ctr, Chicago, IL 60605 USA Consorzio Parco Nazl Stelvio, Bormio, Sondrio, Italy Univ Grenoble Alpes, Irstea, UR LESSEM, BP 76, F-38402 St Martin Dheres, France Univ Bayreuth, BayCEER, D-95447 Bayreuth, Germany Natl Park Schwarzwald, D-77889 Seebach, Germany Univ New South Wales, Evolut & Ecol Res Ctr, Sydney, NSW 2052, Australia Univ New South Wales, Sch Biol Earth & Environm Sci, Sydney, NSW 2052, Australia Penn Game Commiss, Harrisburg, PA 17110 USA Princeton Univ, Dept Ecol & Evolutionary Biol, Princeton, NJ 08544 USA Univ Konstanz, Dept Biol, D-78467 Constance, Germany Off Natl Chasse & Faune Sauvage, Studies & Expertise DRE, F-01330 Birieux, France Univ Haifa, Dept Evolutionary & Environm Biol, IL-3498838 Haifa, Israel Western Ecosyst Technol Inc, Laramie, WY 82070 USA Aarhus Univ, Arctic Res Ctr, DK-8000 Aarhus C, Denmark Polish Acad Sci, Inst Nat Conservat, PL-31120 Krakow, Poland Univ Porto, CIBIO InBIO Associate Lab, P-4485661 Vairao, Portugal Univ Lisbon, Inst Super Agron, InBIO Associate Lab, Ctr Appl Ecol Prof Baeta Neves, P-1349017 Lisbon, Portugal Univ Lisbon, Fac Ciencias, Ctr Ecol Evolut & Environm Changes, P-1749016 Lisbon, Portugal Univ Calif Davis, Dept Environm Sci & Policy, Davis, CA 95616 USA Jackson Hole Conservat, Jackson, WY 83001 USA Univ Vet Med Hannover, Inst Terr & Aquat Wildlife Res, D-30173 Hannover, Germany Univ Calif Santa Cruz, Environm Studies Dept, Ctr Integrated Spatial Res, Santa Cruz, CA 95060 USA Univ Pretoria, Dept Zool & Entomol, ZA-0028 Hatfield, South Africa Colorado State Univ, Dept Fish Wildlife & Conservat Biol, Ft Collins, CO 80523 USA Tatra Natl Pk, PL-34500 Zakopane, Poland Sao Paulo State Univ, Anim Biol Postgra Program, BR-15054000 Sao Jose Do Rio Preto, SP, Brazil

Intergroup competition has an important impact on the survival and fitness of individuals in group-living species. However, factors influencing the probability of winning an encounter are not fully understood. We studied the influence of numerical advantage and location of the encounter on the chances of winning in eight neighboring groups of Verreaux’s sifakas (Propithecus verreauxi), in Kirindy Forest, western Madagascar. Intergroup encounters were inferred from spatial data collected via GPS loggers over a period of two years. Location, i.e., the proximity to the respective core area, rather than the numerical advantage of a group in a given encounter, influenced the probability of winning. Accordingly, the high value that resident groups attribute to exclusive and intensively used areas increased their motivation in defending these locations against intruders. Moreover, losers used the encounter area less often than winners within a month after the encounter, suggesting that losing also entails long-term costs. Thus, our results suggest that in gregarious animals the particular circumstances of each encounter, such as the location, can outweigh group characteristics and predict the chances of winning an intergroup encounter.

Protein limitation has been considered a key factor in hypotheses on the evolution of life history and animal communities, suggesting that animals should prioritize protein in their food choice. This contrasts with the limited support that food selection studies have provided for such a priority in nonhuman primates, particularly for folivores. Here, we suggest that this discrepancy can be resolved if folivores only need to select for high protein leaves when average protein concentration in the habitat is low. To test the prediction, we applied meta‐analyses to analyze published and unpublished results of food selection for protein and fiber concentrations from 24 studies (some with multiple species) of folivorous primates. To counter potential methodological flaws, we differentiated between methods analyzing total nitrogen and soluble protein concentrations. We used a meta‐analysis to test for the effect of protein on food selection by primates and found a significant effect of soluble protein concentrations, but a non‐significant effect for total nitrogen. Furthermore, selection for soluble protein was reinforced in forests where protein was less available. Selection for low fiber content was significant but unrelated to the fiber concentrations in representative leaf samples of a given forest. There was no relationship (either negative or positive) between the concentration of protein and fiber in the food or in representative samples of leaves. Overall our study suggests that protein selection is influenced by the protein availability in the environment, explaining the sometimes contradictory results in previous studies on protein selection. Fil: Ganzhorn, Joerg U.. Universitat Hamburg; Alemania Fil: Arrigo Nelson, Summer J.. California University of Pennsylvania; Estados Unidos Fil: Carrai, Valentina. Università degli Studi di Pisa; Italia Fil: Chalise, Mukesh K.. Tribhuvan University; Nepal Fil: Donati, Giuseppe. Oxford Brookes University; Reino Unido Fil: Droescher, Iris. German Primate Center; Alemania Fil: Eppley, Timothy M.. Universitat Hamburg; Alemania Fil: Irwin, Mitchell T.. Northern Illinois University; Estados Unidos Fil: Koch, Flávia. German Primate Center; Alemania Fil: Koenig, Andreas. Stony Brook University; Estados Unidos Fil: Kowalewski, Miguel Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentina Fil: Mowry, Christopher B.. Berry College; Estados Unidos Fil: Patel, Erik R.. Duke Lemur Center; Estados Unidos Fil: Pichon, Claire. Centre National de la Recherche Scientifique; Francia Fil: Ralison, José. University of Antananarivo; Madagascar Fil: Reisdorff, Christoph. Universitat Hamburg; Alemania Fil: Simmen, Bruno. Centre National de la Recherche Scientifique; Francia Fil: Stalenberg, Eleanor. Australian National University; Australia Fil: Starrs, Danswell. Australian National University; Australia Fil: Terboven, Juana. Universitat Hamburg; Alemania Fil: Wright, Patricia C.. Stony Brook University; Estados Unidos Fil: Foley, William J.. Australian National University; Australia

Fluctuations in food availability are a major challenge faced by primates living in seasonal climates. Variation in food availability can be especially challenging for females, because of the high energetic costs of reproduction. Therefore, females must adapt the particular demands of the different reproductive stages to the seasonal availability of resources. Madagascar has a highly seasonal climate, where food availability can be extremely variable. We investigated the seasonal changes in diet composition, nutrient and energy intake of female and male sifakas (Propithecus verreauxi) in a dry deciduous forest in western Madagascar. We examined how females adjust their diet to different reproductive stages. Seasonality affected the diet of both sexes; particularly in the dry season (Apr-Oct) with low availability of food items, especially fruits, males and females had a reduced nutrient and energy intake compared to the wet season (Nov-Mar) with higher food and fruit availability. The comparison of the diet between sexes in different reproductive stages showed that during the late stage of lactation (Nov-Jan) females had higher food intake, and as a result they had a higher intake of macronutrients (crude protein, fat and non-structured carbohydrates (TNC)) and energy than males. These differences were not present during the pregnancy of females, with both sexes having similar intake of macronutrients and energy during that stage. The increase in the intake of macronutrients observed for females during late lactation could be related to the higher energetic demands of this stage of reproduction. Thus, the observed pattern in the diet indicates that sifaka females are following a capital breeding strategy, whereby females potentially store enough nutrients to cope with the reproduction costs in periods of low food availability.