REPEATED FREEZE-THAW CYCLES BUT NOT SHORT-TERM STORAGE OF FECAL EXTRACTS AT AMBIENT TEMPERATURE INFLUENCE THE STABILITY OF STEROID METABOLITE LEVELS IN CRESTED MACAQUES

The objective of this study was to examine the effects of repeated freeze-thaw cycles and short-term storage of fecal extracts at ambient temperature on the stability of fecal glucocorticoid (fGCM) and estrogen metabolite (fEM) levels from crested macaques.In total 100 aliquots of fecal extracts from fecal samples collected from female crested macaques (Macaca nigra) living at the Tangkoko-Batuangus Nature Reserve, North Sulawesi were used. We performed two different experiments: (1) An experiment to investigate if levels of fGCM and fEM measured from fecal extracts that were exposed to two, four, six and eight repeated freeze-thaw cycles (test groups) differ to control samples (i.e. fecal extracts always stored frozen); (2) An experiment to evaluate whether storing fecal extracts at ambient temperature for two, four, six, and eight days (test groups)affects the levels of fGCM and fEM compared to the control group (i.e. fecal extracts frozen immediately).Results showed that hormone levels were significantly increased (P0.05) after four freeze-thaw cycles for fGCM and after eight freeze-thaw cycles for fEM. By contrast, there was no significant difference (P0.05) in levels of fGCM and fEM between the test groups and the control group in fecal extracts stored at ambient temperature. In conclusion, our data show that more than two and six repeated freeze-thaw cycles should be avoided when measuring fGCM and fEM in crested macaque fecal extracts, respectively. We also demonstrate that storing fecal extracts at ambient temperature is possible for at least 8 days without taking a risk of affecting the stability of fGCM and fEM levels

Identification of Follower Status Based on Male Proximity Score in Crested Macaque

Crested macaque live in multimale-multifemale social groups where temporary association (consortship) typically occurs. Current theory and these limited qualitative observations suggest the hypothesis that behavior functions as a means for males to gain access to fertile females. The aim of this study was to investigate follower status based on quantitative method. Males were classified as either “consort males,” “followers,” and “non-followers” based on proximity maintanance every 15 minute uses scan sampling. Tactics used by followers were classified into 1) individual challenge, 2) coalitionary challenge, 3) abandoned takeover, and 4) opportunistic takeover. The proportion of successful takeovers by followers was calculated by dividing the number of takeovers by followers by the total number of observed takeovers. The proportion of followers is higher than average on D-5 and earlier, D-4, and D-3. Only two of the four consort takeover tactics were used by followers. For abandoned which made up 40% and for individual tactic was made up to 11.5% of consort takeovers tactic used. This study contribute to our understanding of alternative mating strategy in primate and provide the first quantitative data demonstrating that following is an alternative mating strategy in crested macaque (Macaca nigra)

FAECAL GLUCOCORTICOID MEASUREMENT AS INDICATOR STRESS IN WILD CRESTED MACAQUES (MACACA NIGRA): THE IMPORTANCE OF VALIDATION AND SAMPLE PROCESSING TECHNIQUES

Monitoring of physiological stress in wild and/or endangered animals living in their natural habitat can be generated via measuring faecal glucocorticoid metabolites (FGCMs) through enzyme immunoassay technique. However, a careful validation of each enzyme immunoassays (EIAs) and methodological issues such as samples preservation, and extraction procedures must be a significant concern and validated because  it may influence FGCMs levels. In this present study, the aim was to carry out a biological validation to find reliable EIAs that could be used for non-invasive measurement of glucocorticoid levels in crested macaques. Moreover, we compared three different techniques of preservation: lyophilisation, oven drying and field extraction and three different solvents for extraction: 80% methanol, 90% pure ethanol and 90% commercial alcohol (isopropyl alcohol) to find the simple and practical techniques for sample processing. For hormone analysis, we colIected 189 faecal samples from wild crested macaques living in the Tangkoko-Batuangus Nature Reserve, North Sulawesi, Indonesia. The results show that biological validation can be used to validate measurement of faecal glucocorticoid which 3α,11β-dihydroxy-etiocholanolone was the most reliable EIAsfor this species. Different preservation and solvent extraction were not significantly influenced levels of FGCMs (p0.05). In conclusion, Our study highlights the importance of biological validation of FGCMassays and presents practical techniques for the non-invasive monitoring of physiological stress in crested macaques

Leben in Grenzregionen - "Wo kämen wir denn da hin?"

Wie lebt es sich in einer Grenzregion? Dieser Artikel möchte eine Antwort darauf geben und stützt sich auf eine empirische Erhebung in vier Zwillingsorten der "Großregion". Die Ergebnisse, basierend auf einer postalischen Befragung in den Zwillingsgemeinden sowie auf Face-to-Face-Interviews, zeigen, dass aufgrund der Grenzlage verschiedene finanzielle und praktische Vorteile auf beiden Seiten gesehen werden. Die Zusammenarbeit zwischen den Gemeinden wird vorwiegend als recht positiv beschrieben. Hinsichtlich identifikatorischer Prozesse besteht sowohl ein Zugehörigkeitsgefühl zum Nationalstaat als auch zur (grenzüberschreitenden) Region, wobei sich Unterschiede zwischen den Befragten in den einzelnen Ländern zeigen. Geht es um die Bedeutung der Grenze, so ist der allgemeine Konsens, dass sie kaum mehr wahrnehmbar und das Leben seit ihrem Wegfall komfortabler geworden ist und Vorteile bietet. Gleichzeitig werden verschiedene Herausforderungen gesehen - Aufgaben für die kommenden Jahre.What is life in a border region like? This article aims to answer this question, drawing on empirical research in four twin-villages of the Greater Region. The findings, based on a postal survey in the twin municipalities and face-to-face interviews, show that both sides see the border situation as bringing financial and practical advantages. The cooperation between the municipalities is mostly described very positively. In terms of identityrelated processes, feelings of belonging to both the nation state and the (cross-border) region exist, although there are differences here between those surveyed in the different countries. In terms of the importance of the border, there is general agreement that it is scarcely noticed anymore, and that since its disappearance life has become more convenient and has benefited. Various challenges are also seen - tasks for the coming years

Factors Affecting the Outcome and Intensity of Intergroup Encounters in Crested Macaques (Macaca nigra)

Conspecific animal groups often compete for access to fitness-enhancing resources. The more valuable the resource at stake is, the greater the costs groups can afford to outcompete their neighbours, leading to between-group conflicts. We investigated what factors affected intergroup encounter outcome (win, loss, or draw) and intensity (level of aggression and duration) in wild, crested macaques (Macaca nigra). We collected data on 158 dyadic intergroup encounters among three groups of crested macaques in Tangoko Nature Reserve (Indonesia) between November 2015 and July 2016. Intergroup encounters were more likely to have a clear winner the larger the group size difference was between the opposing groups and when both groups rarely used the intergroup encounter location. Groups tended to win in specific parts of their home range, regardless of the numerical advantage, the frequency of use of the intergroup encounter location and its distance to the closest core area. Most encounters involved aggression, but contact aggression was rare. None of our candidate predictors helped to explain the differences in intergroup encounter escalation. Male intergroup aggression was more common than female intergroup aggression. The probability of female and male participation in intergroup aggression increased with the participation of the other sex. Males chased and attacked females in their group (i.e., herded them) in most encounters. Our study suggests that intragroup sexual conflict occurs during intergroup encounters in crested macaques. More detailed and longer studies on intergroup participation may help to understand the factors behind crested macaque intergroup encounter outcome and intensity

Macaques can contribute to greener practices in oil palm plantations when used as biological pest control

Conversion of tropical forests into oil palm plantations reduces the habitats of many species, including primates, and frequently leads to human–wildlife conflicts. Contrary to the widespread belief that macaques foraging in the forest–oil palm matrix are detrimental crop pests, we show that the impact of macaques on oil palm yield is minor. More importantly, our data suggest that wild macaques have the potential to act as biological pest control by feeding on plantation rats, the major pest for oil palm crops, with each macaque group estimated to reduce rat populations by about 3,000 individuals per year (mitigating annual losses of 112 USD per hectare). If used for rodent control in place of the conventional method of poison, macaques could provide an important ecosystem service and enhance palm oil sustainability

Morphological variants of silent bared‐teeth displays have different social interaction outcomes in crested macaques (Macaca nigra)

Objectives While it has been demonstrated that even subtle variation in human facial expressions can lead to significant changes in the meaning and function of expressions, relatively few studies have examined primate facial expressions using similarly objective and rigorous analysis. Construction of primate facial expression repertoires may, therefore, be oversimplified, with expressions often arbitrarily pooled and/or split into subjective pigeonholes. Our objective is to assess whether subtle variation in primate facial expressions is linked to variation in function, and hence to inform future attempts to quantify complexity of facial communication. Materials and Methods We used Macaque Facial Action Coding System, an anatomically based and hence more objective tool, to quantify “silent bared-teeth” (SBT) expressions produced by wild crested macaques engaging in spontaneous behavior, and utilized discriminant analysis and bootstrapping analysis to look for morphological differences between SBT produced in four different contexts, defined by the outcome of interactions: Affiliation, Copulation, Play, and Submission. Results We found that SBT produced in these contexts could be distinguished at significantly above-chance rates, indicating that the expressions produced in these four contexts differ morphologically. We identified the specific facial movements that were typically used in each context, and found that the variability and intensity of facial movements also varied between contexts. Discussion These results indicate that nonhuman primate facial expressions share the human characteristic of exhibiting meaningful subtle differences. Complexity of facial communication may not be accurately represented simply by building repertoires of distinct expressions, so further work should attempt to take this subtle variability into account

Morphological variants of silent bared-teeth displays have different social interaction outcomes in crested macaques (Macaca nigra)

Objectives: While it has been demonstrated that even subtle variation in human facial expressions can lead to significant changes in the meaning and function of expressions, relatively few studies have examined primate facial expressions using similarly objective and rigorous analysis. Construction of primate facial expression repertoires may, therefore, be oversimplified, with expressions often arbitrarily pooled and/or split into subjective pigeonholes. Our objective is to assess whether subtle variation in primate facial expressions is linked to variation in function, and hence to inform future attempts to quantify complexity of facial communication. Materials and Methods: We used Macaque Facial Action Coding System, an anatomically based and hence more objective tool, to quantify “silent bared‐teeth” (SBT) expressions produced by wild crested macaques engaging in spontaneous behavior, and utilized discriminant analysis and bootstrapping analysis to look for morphological differences between SBT produced in four different contexts, defined by the outcome of interactions: Affiliation, Copulation, Play, and Submission. Results: We found that SBT produced in these contexts could be distinguished at significantly above‐chance rates, indicating that the expressions produced in these four contexts differ morphologically. We identified the specific facial movements that were typically used in each context, and found that the variability and intensity of facial movements also varied between contexts. Discussion: These results indicate that nonhuman primate facial expressions share the human characteristic of exhibiting meaningful subtle differences. Complexity of facial communication may not be accurately represented simply by building repertoires of distinct expressions, so further work should attempt to take this subtle variability into account

Androgen correlates of male reproductive effort in wild male long-tailed macaques (Macaca fascicularis): A multi-level test of the challenge hypothesis.

The challenge hypothesis (Wingfield et al., 1990) has been broadly utilised as a conceptual framework to study male androgen correlates of reproductive challenges in mammals. These studies mainly assessed male androgen responsiveness to a general degree of challenge over extended periods of time. Short term co-variation between the socio-sexual challenging context and androgen levels remains, however, largely understudied. We thus aim at providing a multi-level test of the challenge hypothesis by investigating the inter- and intra-individual variations in faecal androgen excretion associated to 1) breeding seasonality, 2) dominance rank, 3) mate-guarding activity and 4) value of the guarded female. We studied long-tailed macaques, a species in which males engage in highly challenging monopolisation of females over discreet periods of time. This particularity allows testing specifically the predicted increase from level B to level C in the challenge hypothesis. The study was carried out during two reproductive seasons on three groups of wild long-tailed macaques. We combined behavioural observations and non-invasive measurements of faecal androgen metabolite (fAM) levels. We found that, as predicted by the challenge hypothesis, male long-tailed macaques respond not only to seasonal but also to short term reproductive challenges by adapting their androgen levels. First, males exhibited a seasonal rise in fAM levels during the mating period which may be triggered by fruit availability as shown by our phenological data. Second, males had increased androgen levels when mate-guarding females and, across mate-guarding periods, males had higher fAM levels when monopolising high-ranking parous females than when monopolising low-ranking ones. Finally, high-ranking males had higher fAM levels than low-ranking males year round. Our study confirms that, in species with a high degree of female monopolisability, androgen may be an important physiological fitness enhancing tool for males by increasing female monopolisation efficiency (in particular with highly valuable females) and helping males to respond to rank take-over challenges