The carnivores of Madagascar are likely the least studied of the world's carnivores, thus little is known about threats to their persistence. I provide the first long-term assessment of Madagascar's rainforest carnivore community, including: 1) how multiple forms of habitat degradation (i.e., fragmentation, exotic carnivores, human encroachment, and hunting) affect native and exotic carnivore occupancy; 2) how native and exotic carnivore temporal activity overlap and how body size and niche explain these patterns; 3) how native and exotic carnivores spatially co-occur across the landscape and which variables explain these relationships; and 4) how native and exotic carnivores and humans co-occur with lemurs across Madagascar's largest protected landscape: the Masoala-Makira landscape. From 2008 to 2013 I photographically sampled carnivores and conducted line-transect surveys of lemurs at seven study sites with varying degrees of degradation and human encroachment, including repeat surveys of two sites. As degradation increased, exotic carnivores showed increases in activity and occupancy while endemic carnivore, small mammal, and lemur occupancy and/or activity decreased. Wild/feral cats (Felis sp.) and dogs (Canis familiaris) had higher occupancy (0.37 ± SE 0.08 and 0.61 ± SE 0.07, respectively) than half of the endemic carnivore species across the landscape. Additionally, exotic carnivores had both direct and indirect negative effects on native carnivore occupancy. For example, spotted fanaloka (Fossa fossana) occupancy (0.70 ± SE 0.07) was negatively impacted by both wild/feral cat (beta = -2.65) and Indian civets (beta = -1.20). My results revealed intense pressure from hunting (ex. n = 31 fosa Cryptoprocta ferox consumed per year from 2005-2011 across four villages), including evidence that hunters target intact forest where native carnivore and lemur occupancy and/or activity are highest. I found evidence of high temporal overlap between native and exotic carnivores (ex. temporal overlap between brown-tail vontsira Salanoia concolor and dogs is 0.88), including fosa (Cryptoprocta ferox) avoiding dogs and humans across all seasons. However, I found no evidence of body size or correlates of ecological niche explaining temporal overlap among carnivores. Estimates of spatial co-occurrence among native and exotic carnivores in rainforest habitat revealed strong evidence that native and exotic carnivores occur together less often than expected and that exotic carnivores may be replacing native carnivores in forests close to human settlements. For example, falanouc show a strong increase in occupancy when dogs are absent (0.69 ± SE 0.11) compared to when they are present (0.23 ± SE 0.05). Finally, the two-species interaction occupancy models for carnivores and lemurs, revealed a higher number of interactions among species across contiguous forest where carnivore and lemur occupancy were highest. These various anthropogenic pressures and their effects on carnivore and lemur populations, particularly increases in exotic carnivores and hunting, have wide-ranging, global implications and demand effective management plans to target the influx of exotic carnivores and unsustainable hunting affecting carnivore and primate populations across Madagascar and worldwide. / Ph. D.

Ce travail de recherche traite des interactions des hommes et des lémuriens. Ces animaux endémiques de Madagascar, menacés de disparition par la déforestation, représentent à eux seuls plus de cinquante espèces et sous-espèces différentes, dont quelques-unes ont été implantées sur les îles Comores. Les recherches de l'auteure se sont portées sur les connaissances et les représentations, les techniques d'utilisation et les méthodes de classification des sociétés dites traditionnelles à l'égard de leur environnement naturel, en vue d'une meilleure compréhension de ce qui lie ces groupes humains à leur milieu, pour mieux définir à la fois leurs besoins et leurs impacts, mais également leur rôle potentiel dans la conservation et la protection de la biodiversité. Les terrains d'enquêtes à Madagascar étaient situés principalement sur la côte Ouest de la Grande Ile auprès des ethnies Sakalava du Boina, Tsimiety et Bestimisaraka, et sur la côte sud de Mayotte où se sont implantées des populations malgaches.

Detta examensarbete utreder avståndsbedömning med hjälp av bildbehandling och stereoseende för känd kamerauppställning. Idag existerar ett stort antal beräkningsmetoder för att få ut avstånd till objekt, men metodernas prestanda har knappt mätts. Detta arbete tittar huvudsakligen på olika blockbaserade metoder för avståndsbedömning och tittar på möjligheter samt begränsningar då man använder sig av känd kunskap inom bildbehandling och stereoseende för avståndsbedömning. Arbetet är gjort på Bofors Defence AB i Karlskoga, Sverige, i syfte att slutligen användas i ett optiskt sensorsystem. Arbetet utreder beprövade Resultaten pekar mot att det är svårt att bestämma en närmask, avstånd till samtliga synliga objekt, men de testade metoderna bör ändå kunna användas punktvis för att beräkna avstånd. Den bästa metoden bygger på att man beräknar minsta absolutfelet och enbart behåller de säkraste värdena.

<p>This thesis employs a network perspective in studying ecosystems and natural resource management. It explores the structural characteristics of social and/or ecological networks and their implications on societies’ and ecosystems’ ability to adapt to change and to cope with disturbances while still maintaining essential functions and structures (i.e. resilience).</p><p>Paper I introduces terminology from the network sciences and puts these into the context of ecology and natural resource management. Paper II and III focus on habitat fragmentation and how it affects an agricultural landscape in southern Madagascar. Two ecosystem services were addressed: (1) crop pollination by bees, and (2) seed dispersal by ring-tailed lemurs. It is shown that the fraction of the studied landscape presently covered by both crop pollination and seed dispersal is surprisingly high, but that further removal of the smallest habitat patches in the study area could have a severe negative impact on the landscape’s capacity to support these ecosystem services.</p><p>In Papers IV and V, the network approach is used to study social networks and the impact they may have on the management of natural resources. In Paper IV it is found that social networks of low- to moderate link densities (among managers) significantly increase the probability for relatively high and stable utility returns whereas high link densities cause occasional large-scale ecological crises between periods of stable and excessively high utility returns. In Paper V, social networks of a rural fishing community in eastern Africa were analyzed. The results indicate that patterns of communication partly explain the distribution of ecological knowledge among villagers, and that gear type used by small-scale coastal fishermen strongly correlates with their patterns of communication. The results also show that groups most central in the network, and hence potentially most influential, are dominated by one type of fishermen.</p>

This thesis employs a network perspective in studying ecosystems and natural resource management. It explores the structural characteristics of social and/or ecological networks and their implications on societies’ and ecosystems’ ability to adapt to change and to cope with disturbances while still maintaining essential functions and structures (i.e. resilience). Paper I introduces terminology from the network sciences and puts these into the context of ecology and natural resource management. Paper II and III focus on habitat fragmentation and how it affects an agricultural landscape in southern Madagascar. Two ecosystem services were addressed: (1) crop pollination by bees, and (2) seed dispersal by ring-tailed lemurs. It is shown that the fraction of the studied landscape presently covered by both crop pollination and seed dispersal is surprisingly high, but that further removal of the smallest habitat patches in the study area could have a severe negative impact on the landscape’s capacity to support these ecosystem services. In Papers IV and V, the network approach is used to study social networks and the impact they may have on the management of natural resources. In Paper IV it is found that social networks of low- to moderate link densities (among managers) significantly increase the probability for relatively high and stable utility returns whereas high link densities cause occasional large-scale ecological crises between periods of stable and excessively high utility returns. In Paper V, social networks of a rural fishing community in eastern Africa were analyzed. The results indicate that patterns of communication partly explain the distribution of ecological knowledge among villagers, and that gear type used by small-scale coastal fishermen strongly correlates with their patterns of communication. The results also show that groups most central in the network, and hence potentially most influential, are dominated by one type of fishermen.

In an effort to better understand primate behavioural flexibility and responses to low-biomass habitats, behavioural patterns of ring-tailed lemurs (Lemur catta) living in a xerophytic spiny forest habitat in southern Madagascar were examined. Behavioural data were collected over two months on two separate groups living in two distinctly different habitats: a sub-desert spiny forest and a riverine gallery forest. Data on the following behavioural categories integral to primate sociality were collected: time allocation, anti-predator vigilance, predator sensitive foraging, feeding competition, and affiliative behaviour. L. catta living in the spiny forest habitat differed significantly in many behavioural patterns when compared to L. catta living in the gallery forest. I suggest that the ability to successfully alter behavioural strategies to varying ecological conditions allows ring-tailed lemurs to occupy low biomass habitats which are uninhabitable to nearly all other primate species in Madagascar. Lemur catta evolution, behavioural flexibility, and conservation will be discussed.

Behaviour (activity budget, degree of terrestriality, intergroup sociality) and diet, and the impact of proximity to forest edge on both, were compared between two populations of ringtailed lemurs (Lemur catta) inhabiting rocky outcrop/anthropogenic savannah-surrounded forest fragments in south-central Madagascar. Both sites—a fragment in the Tsaranoro Valley local to Andringitra National Park, and a fragment at Anja Special Reserve, adjacent to National Route 7 in the Ambalavao area—are considered sacred forests (sites of human burial) by the local people living in these regions, and are therefore subject to traditional protective prohibitions (fady). Both sites attract tourists, but are managed differently, and the resources available to the L. catta differ between sites, affecting the behaviour of the lemur populations: L. catta at Tsaranoro spent more time feeding, and less time resting and engaging in social behaviour compared with those at Anja, where introduced fruiting trees were available and resource abundance appeared to be relatively higher. Also, L. catta at Tsaranoro were less edge-avoidant, with some groups travelling over 400 meters beyond outside the forest in order to utilize resources at the tourist establishment local to the site. L. catta at Anja were never observed more than nine meters outside the forest. Although the fragments are of similar size and were expected to differ little, many significant behavioural dissimilarities were observed, suggesting the importance of the refinement of rapid assessment techniques for judging the habitat suitability and conservational value of small forest fragments.

No description available.

In an effort to better understand primate behavioural flexibility and responses to low-biomass habitats, behavioural patterns of ring-tailed lemurs (Lemur catta) living in a xerophytic spiny forest habitat in southern Madagascar were examined. Behavioural data were collected over two months on two separate groups living in two distinctly different habitats: a sub-desert spiny forest and a riverine gallery forest. Data on the following behavioural categories integral to primate sociality were collected: time allocation, anti-predator vigilance, predator sensitive foraging, feeding competition, and affiliative behaviour. L. catta living in the spiny forest habitat differed significantly in many behavioural patterns when compared to L. catta living in the gallery forest. I suggest that the ability to successfully alter behavioural strategies to varying ecological conditions allows ring-tailed lemurs to occupy low biomass habitats which are uninhabitable to nearly all other primate species in Madagascar. Lemur catta evolution, behavioural flexibility, and conservation will be discussed.

Aujourd’hui la restriction calorique modérée et chronique (RC) est la seule intervention non génétique capable de ralentir l’apparition de pathologies liées à l’âge et d’accroître la longévité chez plusieurs espèces animales. Le resvératrol (RSV), un composé appartenant au groupe des polyphénols, présente des propriétés thérapeutiques intéressantes et constitue un candidat prometteur comme mimétique des effets d’une RC. Afin d’évaluer l’impact de tels protocoles nutritionnels à long terme, une étude longitudinale a été menée sur une cohorte de 53 mâles microcèbes (Microcebus murinus), modèle primate pertinent pour les recherches sur le vieillissement normal ou pathologique au vue de sa longévité maximale de 12 ans en captivité. Depuis l’intégration des animaux dans l’étude (3 ans d’âge) à l’avancement actuel du projet (8 ans d’âge), des paramètres physiologiques et comportementaux ont été évalués régulièrement au sein de la cohorte, partagée en trois groupes: un groupe soumis à une RC (-30%) et un groupe supplémenté en RSV (200 mg.kg-1.jour-1), comparés à un groupe contrôle (CTL). Avec l’âge, chez les microcèbes CTL, des perturbations sont apparues : diminution de la sensibilité à l’insuline, accumulation de dommages cellulaires, déclin moteur et cognitif (mémoire spatiale de reférence) et déclin de certains marqueurs prédictifs du vieillissement chez cette espèce. La RC a permis une amélioration de la sensibilité à l’insuline et a limité l’accumulation de certains marqueurs du stress oxydant, elle n’a pas entraîné d’amélioration des capacités cognitives, mais a diminué l’anxiété, amélioré les performances motrices et augmenté l’activité locomotrice spontanée. La RC a aussi induit une réponse adaptative métabolique avec une perte de masse corporelle sans réduire les dépenses énergétiques, un abaissement des taux hormonaux d’IGF-1 et de la testostérone suggérant un compromis entre reproduction et survie. Le RSV a mimé une partie des effets bénéfiques démontrés sous RC. Cependant il a permis une amélioration de la mémoire spatiale de travail, absente chez les animaux restreints. Le RSV a également montré des effets opposés à ceux de la RC comme un maintien de la masse corporelle et des taux d’hormones par rapport aux CTL, une augmentation des dépenses énergétiques et des niveaux de testostérone pendant la période de jours longs. Finalement les données de survie actuelles sont prometteuses ; moins de 50% de l’effectif de départ des animaux CTL a survécu, alors que plus de 50% des animaux RC et RSV sont encore vivants, présentant de surcroît un âge moyen à la mort plus élevé d’environ 1 an par rapport aux CTL. Malgré des effets hétérogènes et pourtant bénéfiques, la RC et le RSV sont capables de ralentir l’apparition de certains déclins intrinsèques au vieillissement et d’améliorer la survie des microcèbes, soutenant l’hypothèse selon laquelle ces effets pourraient être induits par des mécanismes différents mais permettant d’atteindre les mêmes issues favorables notamment au niveau de l’espérance de vie. Ces résultats constituent un véritable outil pour la compréhension future des mécanismes sous-jacents au processus du vieillissement mais aussi des voies de régulation cellulaires mises en jeu par la RC et le RSV à moyen et long terme chez un primate / Nowadays moderate and chronic calorie restriction (CR); is the only non-genetic intervention known to slow the onset of age-related diseases and to increase longevity in several animal species. Resveratrol (RSV), a natural compound belonging to the polyphenols group, has therapeutic properties and is a promising candidate as CR effects mimetic. To assess the impact of such long-term nutritional protocols, a longitudinal study was conducted on a cohort of 53 males grey mouse lemurs (Microcebus murinus), a relevant primate model for normal and pathological aging research as regards to its high longevity in captivity, up to 12 years. Since the integration of the animals in the study (3 years old) to the current status of the project (8 years of age), physiological and behavioral parameters were assessed regularly in the cohort divided into three groups: a group submitting to a -30% CR and a group supplemented with RSV (200 mg.kg-1.day-1), compared to a control group (CTL). With age, disturbances appeared in CTL mouse lemurs: decreased insulin sensitivity, accumulation of cellular damage, motor and cognitive decline associated with particular type of memory and a decline of certain predictive biomarkers of aging in this species. CR has improved insulin sensitivity and limited the accumulation of markers of oxidative stress, it has not resulted in improved cognitive abilities but in a decreased anxiety, improved motor performances and an increased spontaneous locomotor activity. CR also induced an adaptive metabolic response with body weight loss without lowering energy expenditure, lower hormone levels of IGF-1 and testosterone, supporting a probable trade-off between reproduction and survival. RSV mimicked some of the beneficial effects demonstrated in CR. However, it has improved the spatial memory task, which was not observed in restricted animals. RSV also showed opposite effects to those of CR, as maintained body weight and hormone levels compared to CTL, an increase in energy expenditure and in testosterone levels during the long day’s season. Finally, the current survival data are promising; less than 50% of the CTL animals survived, while more than 50% of CR and RSV animals are still alive, with in addition a mean age at death about 1 year higher compared with CTL animals. Despite heterogeneous, but yet beneficial effects, CR and RSV were able to slow the appearance of some intrinsic age-related declines and to improve the lemurs’ survival, supporting the hypothesis that these effects may be mediated by different mechanisms achieving the same positive outcomes including enhanced life expectancy. These evidences are a real tool for the future understanding of the mechanisms underlying the aging process but also of cellular regulatory pathways that are involved in long term CR and RSV treatment in a primate