Viltets respons på lokalbefolkningens aktivitet i neotropiske verneområder

Medium- to large-bodied vertebrates are of critical importance to the integrity of natural ecosystems, sustaining the composition and structure of plant and faunal communities and the associated ecosystem services. Through distinct mechanisms, such as competition, predation and trophic cascades, they are able to promote profound influences across the entire plant and faunal community structure. These vertebrate species are often game vertebrates of great importance for local subsistence and cash, as they may serve as essential sources of food and other byproducts, particularly for human populations in rural areas. Despite their importance, game vertebrates have been severely impacted by human activities, and even natural areas with small, sparse rural populations are also likely to have their game populations affected by anthropogenic factors. This thesis aims to investigate the patterns of subsistence hunting practiced by human populations living within or in the vicinity of natural protected areas and how hunting and related anthropogenic activities affect local game communities. The study also attempts to shed light on the effectiveness of protected areas in maintaining viable populations of medium- to large-bodied vertebrates. To advance these goals, game vertebrate populations occurring at eight distinct South American protected areas were surveyed using line-transect censuses, camera-trapping surveys and censuses along rivers. Moreover, influences of local human populations on game communities were assessed by conducting household interviews and gathering information on other activities practiced by these rural populations. The occurrence of a large assemblage of game species in all surveyed sites is a resounding confirmation of the importance of protected areas for biodiversity conservation. Yet, the results also provided evidence that game vertebrate communities within these protected areas are being significantly affected by local human populations, with areas under different levels of influence of human activities diverging in the structure and composition of game communities. The claim that hunting is likely to be a major factor altering game populations in natural areas was corroborated by this study. However, the results also showed that game populations are greatly affected by other activities associated with rural populations. Overgrazing from cattle husbandry activities were related to lower occupancies of the most vulnerable game species surveyed, whereas compensatory modes of animal protein acquisition such as fishing was found to have a strong influence on hunting patterns, thereby indirectly affecting game offtake levels in some surveyed sites. These results underline the inter-relationship and synergistic effects of such activities, and the need to account for all the different aspects of rural livelihoods in ensuring the long-term persistence of neotropical game vertebrates.Mellomstore og store virveldyr har en avgjørende betydning for særpreget til naturlige økosystemer. De er med på å opprettholde sammensetning og struktur av de ulike plante- og dyresamfunnene, og tilhørende økosystemtjenester. Gjennom ulike mekanismer, som for eksempel konkurranse og predasjon, har de stor innflytelse over strukturen til hele plante- og dyresamfunn. Mange virveldyrarter er ofte av stor betydning for menneskers tilværelse og økonomi. De kan være viktige som matkilder og andre biprodukter, særlig blant befolkninger i rurale strøk. Til tross for sin store betydning, har mange små- og storviltpopulasjoner blitt sterkt negativt påvirket av menneskelig aktivitet. Til og med i naturområder med små, spredte, rurale befolkninger er det sannsynlig at mange viltbestander påvirkes av menneskelig aktivitet. Denne oppgaven tar sikte på å undersøke jaktmønstrene til mennesker som lever innenfor eller i nærheten av naturvernområder, og hvordan jakt og annen menneskelig aktivitet påvirker lokale viltpopulasjoner. Studien forsøker også å belyse betydningen av naturvernområder for å opprettholde levedyktige bestander av viltpopulasjoner. For å undersøke dette ble det brukt transekttellinger, viltkameraundersøkelser og tellinger langs elver for å kartlegge viltbestander i åtte forskjellige søramerikanske naturreservater. Videre ble lokalbefolkningens påvirkning av viltpopulasjoner undersøkt ved intervjuer i husstander og ved å samle informasjon om andre aktiviteter utført av den rurale befolkningen. Høy konsentrasjon av mange viltarter i de undersøkte områdene er en god bekreftelse på at naturvernområder er viktig for bevaring av biologisk mangfold. Resultatene viser likevel også at viltsamfunn i mange av disse verneområdene blir vesentlig påvirket av lokalbefolkningen. Viltsamfunn i områder med ulik grad av menneskelig påvirkning viser seg å ha forskjellig struktur og sammensetning. Påstanden om at jakt kan være en viktig faktor for å redusere viltbestander i naturområder ble bekreftet i dette studiet. Resultatene viste imidlertid at viltbestander også kan være sterkt påvirket av andre aktiviteter knyttet til den rurale befolkningen. Overbeiting av storfe hadde stor negativ betydning for de mest sårbare viltartene som ble undersøkt. Utnyttelse av alternative animalske proteinkilder, for eksempel fra fisk, hadde sterk innflytelse på jaktmønstre, og påvirket dermed indirekte mengden vilt som ble jaktet i enkelte av områdene. Disse resultatene understreker forholdet og synergieffektene mellom ulike aktiviteter og behovet for å ta hensyn til de forskjellige aspektene av levekår i rurale strøk for å sikre den langsiktige bevaringen av neotropiske viltbestander

Human-Induced Trophic Cascades along the Fecal Detritus Pathway

Human presence and activity in tropical forest is thought to exert top-down regulation over the various ‘green-world’ pathways of plant-based foodwebs. However, these effects have never been explored for the ‘brown-world’ pathways of fecal-detritus webs. The strong effects of humans on tropical game mammals are likely to indirectly influence fecal detritivores (including Scarabaeine dung beetles), with subsequent indirect impacts on detrivore-mediated and plant-facilitating detrital processes. Across a 380-km gradient of human influence in the western Brazilian Amazon, we conducted the first landscape-level assessment of human-induced cascade effects on the fecal detritus pathway, by coupling data on human impact, game mammal and detritivore community structure, and rate measurements of a key detritus process (i.e. dung beetle-mediated secondary seed dispersal). We found evidence that human impact indirectly influences both the diversity and biomass of fecal detritivores, but not detritivore-mediated processes. Cascade strength varied across detritivore groups defined by species' traits. We found smaller-bodied dung beetles were at higher risk of local decline in areas of human presence, and that body size was a better predictor of cascade structure than fecal resource manipulation strategy. Cascade strength was also stronger in upland, unflooded forests, than in seasonally flooded forests. Our results suggest that the impact of human activity in tropical forest on fecal-detritus food web structure is mediated by both species' traits and habitat type. Further research will be required to determine the conditions under which these cascade effects influence fecal-detritus web function

Wild dogs at stake: deforestation threatens the only Amazon endemic canid, the short-eared dog (Atelocynus microtis)

The persistent high deforestation rate and fragmentation of the Amazon forests are the main threats to their biodiversity. To anticipate and mitigate these threats, it is important to understand and predict how species respond to the rapidly changing landscape. The short-eared dog Atelocynus microtis is the only Amazon-endemic canid and one of the most understudied wild dogs worldwide. We investigated short-eared dog habitat associations on two spatial scales. First, we used the largest record database ever compiled for short-eared dogs in combination with species distribution models to map species habitat suitability, estimate its distribution range and predict shifts in species distribution in response to predicted deforestation across the entire Amazon (regional scale). Second, we used systematic camera trap surveys and occupancy models to investigate how forest cover and forest fragmentation affect the space use of this species in the Southern Brazilian Amazon (local scale). Species distribution models suggested that the short-eared dog potentially occurs over an extensive and continuous area, through most of the Amazon region south of the Amazon River. However, approximately 30% of the short-eared dog's current distribution is expected to be lost or suffer sharp declines in habitat suitability by 2027 (within three generations) due to forest loss. This proportion might reach 40% of the species distribution in unprotected areas and exceed 60% in some interfluves (i.e. portions of land separated by large rivers) of the Amazon basin. Our local-scale analysis indicated that the presence of forest positively affected short-eared dog space use, while the density of forest edges had a negative effect. Beyond shedding light on the ecology of the short-eared dog and refining its distribution range, our results stress that forest loss poses a serious threat to the conservation of the species in a short time frame. Hence, we propose a re-assessment of the short-eared dog's current IUCN Red List status (Near Threatened) based on findings presented here. Our study exemplifies how data can be integrated across sources and modelling procedures to improve our knowledge of relatively understudied species

New insights into the distribution and conservation status of the Golden-White Tassel-Ear Marmoset Mico chrysoleucos (Primates, Callitrichidae)

Among the 13 Mico species recognized by the IUCN Red List of Threatened Species, six are listed as "Data Deficient". The geographic range of most of the Mico species has been estimated from only a few records. We report new localities and the geographic extension of Mico chrysoleucos. In addition, we confirmed the presence of the species in two distinct protected areas. We modeled the habitat suitability of M. chrysoleucos using the maximum entropy method and including new records obtained by the authors in the state of Amazonas, Brazil. From the total area of occurrence calculated for the species, 22.8% is covered by protected areas and indigenous lands. The annual mean deforestation rate estimated between 2000 and 2015 was 2.95%, and the total area deforested by 2015 was 3354 km2 or 8.6% of the total distribution limits of the species. The habitat lost between 2000 and 2015 was 3.2% (1131 km2 ) of the total potential distribution, while the habitat loss area legally protected was 31 km2, and the habitat loss in settlements was equal to 691 km2. Our results extend the geographic distribution of the species about 100 km farther south, with the Maracanã River being a possible geographic barrier for the species. The significantly low rate of habitat loss inside protected areas and indigenous land, when compared to unprotected areas, points out the importance of these areas to M. chrysoleucos conservation. The species is relatively wide-ranging, legally protected, and resilient to regional anthropic threats. However, the hydroelectric schemes and the improvement of the road system in southern Amazonia pose an imminent threat to the species

Effects of human-induced habitat changes on site-use patterns in large Amazonian Forest mammals

The Amazon is one of the most diverse biomes around the globe, currently threatened by economic and industrial development and climate change. Large mammals are keystone species, playing an important role in ecosystem structure and function as ecological engineers, while being highly susceptible to deforestation, habitat degradation, and human exploitation. Using a unifying hierarchical Bayesian spatial approach, we examine the site-use patterns of four large Amazonian Forest mammals and their relationships to anthropogenic factors at a biome-wide scale. Our results showed that species’ patterns of site use are correlated with human induced habitat changes, and that this correlation is species-specific. The white-lipped peccary shows highest site-use estimates within strict protected areas, affected by proximity to urban areas and benefiting from indigenous territories, the tapir responding slightly to proximity to burned forested areas, while the giant armadillo and the jaguar were primarily affected by vegetation cover loss; disturbances related to the colonization of the Amazon. Our findings contribute to the understanding of how human-induced environmental changes influence the site-use patterns of these four large mammals, and inform future conservation and land use planning. Transboundary conservation efforts, empowering and integrating native (indigenous and non-indigenous) communities in land governance schemes, involving the private sector and securing the commitment of developed countries are important paths for the protection and sustainability of the globally-crucial Amazon rainforest

Campinarana e índios baniwa: influências ambientais e culturais sobre a comunidade de vertebrados terrestres no alto Rio Negro, AM

In spite of the great diversity of higher-taxa animals found in the Amazonian forest, few studies have tried to characterize the structure of vertebrate communities in the region, and the peculiarities related to different Amazonian physionomies. In this study I analised, using four different methods, the structure of terrestrial vertebrate community found in Amazonian white sand vegetation environment, focusing on the species richness, abundance and density. Information on different species could be obtained by surveying the area and registering direct observations (sights and sounds), animal tracks on sand parcels and animal burrows. Information about other species found in that region could also be obtained by interviewing Baniwa Indians, inhabitants of the area studied. Results show the Upper Rio Negro white sand vegetation as an ecossistem with a very similar vertebrate community when compared to lowland terra firme forest environments, in terms of species richness. On the other hand, most animal populations censed here presented lower values of abundance when compared to other sites in Amazonia, propably influenced by the low productivity of this environment. Here I present the use of wildlife and subsistence hunting among Baniwa Indians, from the Upper Rio Negro River, Amazonia. Just like other studies carried out in different neotropical rainforest sites, Baniwa Indians use a wide array of species for protein consumption and cultural purposes. Different hunting technologies are being employed by this group, resulting in different prey compositions. Despite the short-term study, the game composition and yield obtained indicate a low amount of preys killed and bushmeat obtained by Baniwa Indians, compared to other Indian groups, suggesting the low preference of hunting acitivity to supply the daily protein requirements compared to fishing activity. This behaviour is probably influenced by the low abundance of important game species in the area, although not indicating nutritional resources depletion, noted by the despise for consumption of lesser bodied animals and the presence of taboo areas. Different studies have already demonstrated the influence of subsistence hunting activities affecting the terrestrial vertebrate community structure. But, despite the amount of studies on this subject, it is still difficult to measure the levels of impact caused by this kind of activity. Here I examine the effects of human population size on game species community, known to be one of the greatest concerns in conservation issues, as it increases hunting impact and other deleterious activities on the environment. The species richness was not significantly affected by the cultural and environmental variables measured. The community composition showed a stronger relation to geographic variation, than any other variable measured. Species abundance, on the other hand, tended to vary with human population size. Results indicate that, although environmental factors can affect wildlife composition, even a slight increase of human population is sufficient to cause considerable changes in the game species community.Apesar da grande diversidade de animais encontrada na Amazônia, poucos estudos realizados nessa região buscaram caracterizar a estrutura das comunidades de vertebrados terrestres existentes e as peculiaridades relacionadas aos diferentes tipos de fisionomias existentes. Nesse estudo analisei a estrutura da comunidade de vertebrados terrestres de médio e grande porte em uma região de campinarana, enfocando na riqueza, abundância e densidade populacional das espécies encontradas na região e utilizando, para isso, quatro diferentes métodos de amostragem. Obtive registros dos animais existentes nessa região através do censo baseado em registros diretos (sonoros e visuais), registros de rastros obtidos em parcelas de areia e registros de tocas. Informações sobre a possível ocorrência de outras espécies também foi obtida por meio de entrevistas com os índios Baniwa, habitantes da região. Os resultados obtidos apresentam a campinarana do Alto Rio Negro como um ambiente onde pode ser encontrada uma comunidade de vertebrados terrestres semelhante, em termos de riqueza, às florestas de terra firme. No entanto, em termos de abundância, as populações encontradas na campinarana apresentaram valores muito baixos, provavelmente inflenciada pelas condições de baixa produtividade da região. Apresento nesse estudo o uso da vida silvestre e a caça de subsistência praticada pelos índios Baniwa, do Alto Rio Negro, na região Amazônica. Assim como outros estudos realizados em diferentes locais nas florestas neotropicais, os índios Baniwa usam uma ampla gama de espécies para consumo proteico e por motivos culturais. Diferentes tecnologias de caça são empregadas por esses grupos, resultando em diferentes composições de caça. Apesar do curto tempo empregado para avaliar a composição da caça e a taxa de consumo de caça, os dados obtidos indicam uma baixa quantidade de presas abatidas pelos Baniwa, comparado com outros grupos indigenas, sugerindo uma baixa preferência da atividade da caça como forma de suprir as necessidades proteicas diárias em comparação com a atividade da pesca, provável reflexo da baixa abundância das espécies caçadas na região, sem, no entanto, indicar uma alta pauperização de recursos alimentares, como mostra o desprezo pelas espécies de menor tamanho e a existência de espécies tabú. Apesar de estudos realizados na Amazônia e em outras regiões demostrarem que a caça praticada por povos indígenas atuam influenciando a estrutura das comunidades de animais visados pela caça, ainda há dificuldades em se mensurar essas alterações. Apresento aqui uma análise da variação da comunidade de vertebrados ao longo de uma região na Amazônia e a relação desta com variáveis ambientais e com o tamanho das aldeias indígenas existentes na região, visto que o aumento demográfico humano, inflacionando a caça e outras atividades potencialmente deletérias ao animais, é uma das maiores preocupações atuais quando se discute conservação. A riqueza não mostrou ser significativamente influenciada pelas variáveis medidas. A abundância das espécies, no entanto, mostrou uma considerável relação com o aumento populacional na região. Os resultados indicam que, apesar de fatores ambientais serem importantes agentes influenciando a composição da comunidade de animais caçados na região, o acréscimo de poucas pessoas na área estudada já é o suficiente para também surtir efeito nessa comunidade

Flood pulse dynamics affects exploitation of both aquatic and terrestrial prey by Amazonian floodplain settlements

Rural populations in the tropics frequently rely on game vertebrates and fish to supply their daily protein requirements. However, few studies have quantified the environmental and socioeconomic drivers of hunting and fishing effort and the potential compensatory relationship between these extractive activities. Here, we assessed game and fish extraction by 222 semi-subsistence households from 28 villages along a major white-water tributary of Brazilian Amazonia. During the 44 months study, a total of 32,114 kg of game and 261,752 kg of fish were harvested, amounting to an average extraction rate of 30.5 ± 109.9 g person− 1 day− 1 and 1519.4 ± 1037.6 g person− 1 day− 1 for game and fish, respectively. While 97.93 ± 0.03% of all fishing trips resulted in fish catches, only 77.12 ± 27.02% of the hunting forays successfully obtained at least one forest vertebrate. The flood pulse had a strong effect on both fishing and hunting activities. However, the seasonally rising floodwaters had a negative effect on fish yield and catch per unit effort (CPUE), but had a positive effect on game yields. Game yield was also an important variable explaining fish yield, indicating a strong compensatory interaction between these two forms of protein acquisition. Our results highlight the importance of considering different modes of animal protein harvesting in conservation planning and management of both forest vertebrates and aquatic organisms

Consequences of actor level livelihood heterogeneity for additionality in a tropical forest payment for environmental services programme with an undifferentiated reward structure

Primary tropical forests provide crucial environmental services, including carbon storage and hydrological regulation. Options for promoting forest conservation include payments for environmental services (PES) programmes that provide financial incentives to local actors, in exchange for reduced forest clearance. The success of voluntary PES (defined in terms of avoided primary forest conversion) is contingent upon behavioural changes in enrolled actors. As both the degree of enrolment and likelihood of sustained behavioural change depend upon how PES compensation structures interact with existing actor economies, local heterogeneity in livelihood strategies may play a strong role in the ultimate success of PES programmes, particularly when compensation is not differentiated with respect to opportunity costs. We examined the influence of livelihood heterogeneity on the potential success of a deforestation-reduction PES with an undifferentiated reward structure. We collected socioeconomic and demographic data at the household and community levels across two large Amazonian extractive reserves where a spatially extensive PES programme (Bolsa Floresta) operates. We show that demographic and socioeconomic status varies widely across households and communities, and found that both households and communities that are most and least likely to convert primary forest receive similar financial incentives. Those households most engaged in manioc agriculture (the primary driver of local primary forest conversion) both benefitted from the highest annual incomes and incurred the greatest opportunity costs. We show that avoided primary forest conversion could be greatly increased with differentiated payment structures adjusted for local differences in opportunity costs and livelihood strategies, and present two metrics that could help to achieve that goal

Determinants of livelihood strategy variation in two extractive reserves in Amazonian flooded and unflooded forests

Extractive reserves account for a significant proportion of the remaining intact forest within Brazilian Amazonia. Managers of extractive reserves need to understand the livelihood strategies adopted by rural Amazonians in order to implement projects that benefit the livelihoods of local residents whilst maintaining forest integrity. Whilst resident populations are often descended from immigrant rubber-tappers, dynamic economic and social conditions have led to a recent diversification of land-use practices. This two-year study in two large contiguous extractive reserves encompassing both unflooded (terra firme) and seasonally flooded (várzea) forest, shows the degree to which local livelihood strategies of different settlements are heterogeneous. Extractive offtake of forest products and fish catches and agricultural activities, together with income from sales, for 82 households in 10 communities were quantified in detail by means of weekly surveys. The survey data were combined with interviews to examine the demographic and wealth profile, and engagement in alternative activities, in 181 households across 27 communities. All households and communities were engaged in all three subsistence activity types, but there was large variation in engagement with income-generating activities. Households within a community showed considerable congruence in their income-generating activity profiles, but there was significant variation between communities. Yields from agriculture and fishing were more temporally stable than extraction of highly-seasonal forest products. Generalized linear mixed models showed that forest type was consistently important in explaining yields of both agrarian and extractive products. Communities with greater access to terra firme forest were inherently more agricultural, and strongly committed to manioc production. Communities with greater access to flooded forest, however, showed a greater dependence on fishing. Conservation should be more attuned to the diversity and dynamism of livelihood strategies in protected areas; in particular, reserve managers and policy makers should account for the effect of local variation in physical geography when designing sustainable development projects