Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 21
Filter
Add more filters










Publication year range
1.
J Neurol Sci ; 446: 120564, 2023 03 15.
Article in English | MEDLINE | ID: mdl-36731358

ABSTRACT

Alzheimer's disease (AD) is the most common form of dementia found in the elderly and disease progression is associated with accumulation of Amyloid beta 1-42 (Aß42) in brain. An immune-mediated approach as a preventive intervention to reduce amyloid plaques without causing brain inflammation is highly desirable for future clinical use. Genetic immunization, in which the immunizing agent is DNA encoding Aß42, has great potential because the immune response to DNA delivered into the skin is generally non-inflammatory, and thus differs quantitatively and qualitatively from immune responses elicited by peptides, which are inflammatory with production of IFNγ and IL-17 cytokines by activated T cells. DNA immunization has historically been proven difficult to apply to larger mammals. A potential barrier to use DNA immunization in large mammals is the method for delivery of the DNA antigen. We tested jet injection in mice and rabbits and found good antibody production and safe immune responses (no inflammatory cytokines). We found significant reduction of amyloid plaques and Aß peptides in brains of the DNA Aß42 immunized 3xTg-AD mouse model. This study was designed to optimize DNA delivery for possible testing of the DNA Aß42 vaccine for AD prevention in a clinical trial.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Mice , Rabbits , Animals , Amyloid beta-Peptides/metabolism , Plaque, Amyloid , Peptide Fragments , Immunotherapy , Brain/metabolism , Cytokines , Immunization/methods , Injections, Jet , DNA , Mice, Transgenic , Disease Models, Animal , Mammals/genetics , Mammals/metabolism
2.
Sci Total Environ ; 853: 158679, 2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36099955

ABSTRACT

Large forested landscapes often harbour significant amount of biodiversity and support mankind by rendering various livelihood opportunities and ecosystem services. Their periodic assessment for health and ecological integrity is essential for timely mitigation of any negative impact of human use due to over harvesting of natural resources or unsustainable developmental activities. In this context, monitoring of mega fauna may provide reasonable insights about the connectivity and quality of forested habitats. In the present study, we conducted a largest non-invasive genetic survey to explore mammalian diversity and genetically characterized 13 mammals from the Indian Himalayan Region (IHR). We analyzed 4806 faecal samples using 103 autosomal microsatellites and with three mitochondrial genes, we identified 37 species of mammal. We observed low to moderate level of genetic variability and most species exhibited stable demographic history. We estimated an unbiased population genetic account (PGAunbias) for 13 species that may be monitored after a fixed time interval to understand species performance in response to the landscape changes. The present study has been evident to show pragmatic permeability with the representative sampling in the IHR in order to facilitate the development of species-oriented conservation and management programmes.


Subject(s)
Conservation of Natural Resources , Ecosystem , Animals , Humans , Biodiversity , Mammals/genetics
3.
Ecol Evol ; 12(2): e8529, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35169447

ABSTRACT

Medium and large-sized mammals of Jorgo-Wato Protected Forest have not yet been documented though the forest established before four decades. Hence, this study aims to document medium and large mammals and the behavioral responses of selected mammals toward anthropogenic activities in the study area. The study was conducted from February 2015 to June 2016, encompassing the wet and dry seasons. Data were collected mainly through camera traps, indirect and direct evidence. The study revealed about 23 medium and large-sized mammals that belong to seven orders namely Bovidae, Carnivora, Primates, Rodentia, Tubulidentata, Lagomorpha, and Hyracoidea. Papio anubis, C. guereza, and C. aethiops were the most abundant large mammals in JWPF. Because of high anthropogenic activities, African buffalo shifted its activity period from diurnal into crepuscular and nocturnal. African buffalo traveled longer distances during the wet season (mean = 14.33 km, SD = 1.25 km) than during the dry season (mean = 9.00 km, SD = 2.16 km). This could be due to the fact that the local people were less likely to go to the forest for resource exploitation during the wet season as they are fully engaged in agricultural activities. However, low agricultural activities during the dry season allow the local people to extract resources and involve in bushmeat hunting which could limit the movement of mammals to their refugia. African buffalo preferred to rest on and adjacent to a gravel road (22.1%) in the forest, followed by on open rocky hilltops (14.7%) at night time, but rest in the bottomland thicket vegetation during the dry daytime. Regardless of high human pressure in the area, this study has revealed a good number of medium and large-sized mammals that could be used as baseline information to design a sound conservation and management action plan of large mammals and their habitat in Jorgo-Wato Protected Forest.

4.
Sci Total Environ ; 758: 144000, 2021 Mar 01.
Article in English | MEDLINE | ID: mdl-33338787

ABSTRACT

With climate change, terrestrial fauna in riparian floodplain ecosystems must adapt to a predicted increase in frequency and magnitude of fluvial perturbations. Seasonal migration to seek refuge from floodwaters represents a central adaptation strategy, but may entail risky navigation of anthropogenic spaces in heterogeneous landscapes. Here, we demonstrate the opportunities and constraints large-bodied mammalian herbivores face during an adaptive response of obligatory flood-driven refuge migration, across a human-dominated environment. Our study system, centred around a productive protected area--Kaziranga National Park in Assam, Northeast India--on the floodplains of the Brahmaputra River, is home to an abundance of large herbivores that undertake seasonal migrations in response to floods. We contrast species distribution data during a major flood event with those from the dry season to illustrate season-specific movement and space use decisions of large herbivores ranging in body mass from the 3000-kg Asian elephant Elephas maximus to the 20-kg muntjac Muntiacus muntjak. In the dry season, most large herbivores--a majority of which are endangered and threatened by anthropogenic pressures--avoided areas with a strong human footprint, while preferring spaces with high land-use diversity. During the floods, such species were pushed out of inundated habitats within the protected area, and they chose to move through woodlands and areas under bamboo cover on private lands, as they migrated to forested refugia on higher ground. Our results show how seasonal environmental constraints shaped by floods determine the internal motivation of animals to risk traversing a human-dominated space to seek refuge, which contextually defines how animals view and navigate the landscape. Such insights underscore the importance of dynamic and adaptive planning, and participatory conservation efforts, to facilitate connectivity in the changing environment and climate of the present Anthropocene.


Subject(s)
Ecosystem , Floods , Animals , Climate Change , Conservation of Natural Resources , Humans , India , Rivers
5.
Biota Neotrop. (Online, Ed. ingl.) ; 21(3): e20201173, 2021. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1278411

ABSTRACT

Abstract: The state of Goiás, in central Brazil, is covered mainly by the Cerrado domain, with the Alto Paraná Atlantic Forest occupying its central-southern portion. Goiás is one of the 20 Brazilian federative units without a mammal checklist. In this study, we provide the first checklist of mammals from Goiás state. We recorded mammal species based primarily on the analysis of specimens housed in scientific collections as well as on literature with associated voucher material. We listed 191 mammalian species belonging to 125 genera, 31 families and 10 orders, which represents 25.2% of the mammal species occurring in Brazil. The most speciose orders were Chiroptera (90 spp.), followed by Rodentia (43 spp.), Carnivora (19 spp.) and Didelphimorphia (17 spp.). The following orders accounted for a smaller portion of the state diversity: Cetartiodactyla (7 spp.), Cingulata (7 spp.), Primates (4 spp.), Pilosa (2 spp.), Lagomorpha (1 sp.), and Perissodactyla (1 sp.). A total of 28 species (14.7%), mainly represented by medium and large-sized mammals, are nationally threatened while 12 (6.3%) are globally threatened. Our results indicate great portions of the state lacking a proper survey of mammals, especially the northwestern portion. We discuss species richness, distribution and conservation status of the mammals of Goiás state in national and regional scenarios. We highlight the need for mammal inventories based on complementary survey techniques with the collection of vouchers in order to provide karyologic, molecular, morphologic, parasitologic, and ecological data. These informations are the basis for integrative studies that lead to the understanding of current mammalian richness and diversity. Indeed, knowledge on species richness distribution in the state will guide conservation strategies, especially in areas undergoing habitat loss and fragmentation, such as the central-southern portion of Goiás.


Resumo: O estado de Goiás, no Brasil central, é coberto principalmente pelo domínio do Cerrado, com a Mata Atlântica do Alto Paraná ocupando sua porção centro-sul. Goiás é uma das 20 unidades federativas brasileiras que ainda não possui uma lista de espécies de mamíferos. Neste estudo, apresentamos a primeira lista de mamíferos para o estado. Registramos as espécies de mamíferos com base principalmente na análise de espécimes depositados em coleções científicas, bem como na literatura apresentando material testemunho associado. Listamos 191 espécies pertencentes a 125 gêneros, 31 famílias e 10 ordens, as quais representam 25,2% das espécies de mamíferos que ocorrem no Brasil. As ordens mais especiosas foram Chiroptera (90 spp.), seguida pelas ordens Rodentia (43 spp.), Carnivora (19 spp.) e Didelphimorphia (17 spp.), com as demais ordens respondendo por uma porção menor da diversidade: Cetartiodactyla (7 spp.), Cingulata (7 spp.), Primates (4 spp.), Pilosa (2 spp.), Lagomorpha (1 sp.) e Perissodactyla (1 sp.). Um total de 28 espécies (14,7%), principalmente representadas por mamíferos de médio e grande porte, estão ameaçadas nacionalmente e 12 (6,3%) encontram-se globalmente ameaçadas. Nossos resultados indicaram grandes porções do estado ainda não devidamente pesquisadas em relação aos seus mamíferos, com informações escassas e fragmentadas, principalmente no que diz respeito à sua porção noroeste. Discutimos a riqueza de espécies, a distribuição e o estado de conservação dos mamíferos do estado de Goiás nos cenários nacional e regional. Ressaltamos a importância da realização de inventários que utilizem técnicas complementares de amostragem, incluindo a coleta de material testemunho, proporcionando a obtenção de dados cariotípicos, moleculares, morfológicos, parasitológicos e ecológicos. Estas informações são a base de estudos integrativos, os quais aumentam nossa compreensão a respeito da riqueza e diversidade atual dos mamíferos. O conhecimento a respeito da distribuição da riqueza de espécies em Goiás é essencial para embasar estratégias de conservação, tão necessárias em áreas que vem sofrendo com a perda e fragmentação de seus hábitats naturais, como a porção centro-sul do estado.

6.
Sci Total Environ ; 742: 140712, 2020 Nov 10.
Article in English | MEDLINE | ID: mdl-32721759

ABSTRACT

Tropical forests inhabited by endangered orangutans, rhinos, tigers, and elephants in South-east Asia are threatened by deforestation, including oil palm expansion. Certification has been proposed to label sustainable palm oil production. However, from a remotely sensed time-series and imagery analysis (1984-2020), we discovered that most of the currently certified grower supply bases and concessions in Sumatra and Borneo are located in the 1990s large mammals habitat and in areas that were biodiverse tropical forests less than 30 years ago. In light of this dramatic evidence, we suggest that certification schemes claim for the "sustainable" production of palm oil just because they neglect a very recent past of deforestation and habitat degradation.


Subject(s)
Conservation of Natural Resources , Forests , Animals , Asia, Southeastern , Borneo , Certification , Ecosystem , Indonesia , Palm Oil
7.
Conserv Biol ; 34(4): 819-828, 2020 08.
Article in English | MEDLINE | ID: mdl-32406975

ABSTRACT

Former ranges of wild animals have been reestablished in many developed countries. However, this reestablishment has led to increasing human-wildlife conflict in agroforest ecosystems. In Japan, human-wildlife conflict, such as crop raiding by and ecological impacts of wild ungulates and primates, is a serious problem in depopulated rural areas due to these animal range expansions and increased abundances. Japan's human population is predicted to decline by 24% by 2050, and approximately 20% of agricultural settlements will become completely depopulated. In this scenario, anthropogenic pressures on wildlife (e.g., hunting and habitat alteration) will continue to decrease and human-wildlife conflict will increase due to increasing wildlife recovery. Japan's local governments plan to slow range recovery, prevent species reestablishment, or remove recolonizing large mammals through lethal control. This strategy, however, is not cost-effective, and workforce shortages in depopulated communities make it infeasible. Moreover, the suppression of wildlife prevents the recovery of ecological functions and thus would degrade regional biodiversity. The declining pressure on wildlife that accompanies human depopulation will prevent the restoration of any past states of human-wildlife interaction. We suggest human-used areas in rural landscapes be aggregated in compact cities and that in transition zones between human settlements and depopulated lands that land-sharing approaches be applied. Concentrating management efforts in compact cities may effectively decrease human-wildlife conflict, rather than intensifying human pressures. Reforestation of depopulated lands may lead to recovery of wildlife habitats, their ecosystem functions, and regional biodiversity due to minimization of negative anthropogenic effects (land-sparing approach). Balancing resolution of human-wildlife conflict and ecological rewilding could become a new, challenging task for regional wildlife managers.


Una Estrategia para el Manejo de Fauna en Áreas Rurales Despobladas de Japón Resumen Las distribuciones geográficas históricas de algunos animales silvestres se han reestablecido en muchos países desarrollados. Sin embargo, este restablecimiento ha derivado en un incremento del conflicto humano - fauna en los ecosistemas agroforestales. En Japón, el conflicto humano - fauna, como el asalto de cultivos y los impactos ecológicos de los primates y ungulados, es un problema serio en las áreas rurales despobladas debido a la expansión de la distribución y al incremento en abundancia de estos animales. Está pronosticado que la población humana de Japón decline en un 24% para 2050 y ∼20% de los establecimientos agrícolas estarán completamente despoblados. Bajo este escenario, las presiones antropogénicas sobre la fauna (como la caza y la alteración del hábitat) continuarán disminuyendo y el conflicto humano - fauna incrementará debido a la recuperación de la fauna. El gobierno local de Japón planea retrasar la recuperación de las distribuciones, prevenir el restablecimiento de las especies o remover a los mamíferos mayores en proceso de recolonización por medio del exterminio. Sin embargo, esta estrategia no es rentable y la escasez de mano de obra en las comunidades despobladas hace que no sea una estrategia factible. Además, la supresión de fauna impide la recuperación de las funciones ecológicas, por lo que terminaría por degradar la biodiversidad regional. La reducción de la presión sobre la fauna que va de la mano con la despoblación humana prevendrá la recuperación de cualquier estado pasado de la interacción humano - fauna. Sugerimos que las áreas usadas por humanos en los paisajes rurales queden agregadas en ciudades compactas y que se apliquen estrategias de tierras compartidas en las zonas de transición entre los asentamientos humanos y las tierras despobladas. La concentración de los esfuerzos de manejo en las ciudades compactas podría disminuir efectivamente el conflicto humano - fauna en lugar de intensificar las presiones humanas. La reforestación de las tierras despobladas podría derivar en la recuperación del hábitat de la fauna, sus funciones ambientales y de la biodiversidad regional debido a la minimización de los efectos antropogénicos (estrategia de tierra parsimoniosa). El balance entre la resolución del conflicto humano - fauna y el retorno ecológico a la vida silvestre podría convertirse en una tarea nueva y exigente para los administradores regionales de la fauna.


Subject(s)
Animals, Wild , Ecosystem , Animals , Biodiversity , Conservation of Natural Resources , Humans , Japan
8.
Pediatr Cardiol ; 40(7): 1345-1358, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31346664

ABSTRACT

The neonatal capacity for cardiac regeneration in mice is well studied and has been used to develop many potential strategies for adult cardiac regenerative repair following injury. However, translating these findings from rodents to designing regenerative therapeutics for adult human heart disease remains elusive. Large mammals including pigs, dogs, and sheep are widely used as animal models of humans in preclinical trials of new cardiac drugs and devices. However, very little is known about the fundamental cardiac cell biology and the timing of postnatal cardiac events that influence cardiomyocyte proliferation in these animals. There is emerging evidence that external physiological and environmental cues could be the key to understanding cardiomyocyte proliferative behavior. In this review, we survey available literature on postnatal development in various large mammal models to offer a perspective on the physiological and cellular characteristics that could be regulating cardiomyocyte proliferation. Similarities and differences between developmental milestones, cardiomyocyte maturational events, as well as environmental cues regulating cardiac development, are discussed for various large mammals, with a focus on postnatal cardiac regenerative potential and translatability to the human heart.


Subject(s)
Cell Proliferation/physiology , Heart/physiology , Regeneration/physiology , Animals , Disease Models, Animal , Dogs , Humans , Myocytes, Cardiac/physiology , Sheep , Swine
9.
J Environ Manage ; 217: 690-699, 2018 Jul 01.
Article in English | MEDLINE | ID: mdl-29654972

ABSTRACT

A rapidly expanding human footprint - comprised of anthropogenic land-use change and infrastructure - is profoundly affecting wildlife distributions worldwide. Cumulative effects management (CEM) is a regional approach that seeks to manage combined effects of the human footprint on biodiversity across large spatial scales. Challenges to implementing this approach include a lack of ecological data at large spatial scales, the high cost of monitoring multiple indicators, and the need to manage multiple footprints across industries. To inform development of effective CEM, we used large mammals as indicators to address the following questions: a) do species respond more strongly to individual footprint features or to cumulative effects (combined area of all footprint types, measured as total footprint), b) which features elicit the strongest responses across species, and c) are the direction of responses to footprint consistent? We used data from 12 years of snowtrack surveys (2001-2013) in the boreal forest of Alberta, coupled with regional footprint and landcover data, to develop generalized linear mixed-effects models relating the relative abundance of five boreal mammals [gray wolf (Canis lupus), Canada lynx (Lynx canadensis), coyote (Canis latrans), white-tailed deer (Odocoileus virginianus) and moose (Alces alces)] to individual and cumulative effects of the human footprint. We found that across species the strongest responses were to agriculture, roads, and young cutblocks (<10 years), suggesting these as potential priority stressors to address within CEM. Most species also responded to total footprint, indicating that in the absence of detailed information on individual features, this coarse measure can serve as an index of cumulative effects. There was high variability in direction and magnitude of responses across species, indicating that community-level responses are likely and should be considered within CEM planning.


Subject(s)
Biodiversity , Deer , Human Activities , Alberta , Animals , Animals, Wild , Ecology , Humans , Population Dynamics
10.
Ecol Appl ; 28(1): 106-118, 2018 01.
Article in English | MEDLINE | ID: mdl-28944528

ABSTRACT

In animal surveys, detectability can vary widely across species. We hypothesized that detectability of animals should be a function of species traits such as mass, color, and mean herd size. We also hypothesized that models of detectability based on species traits can be used to predict detectability for new species not in the original data set, leading to substantial benefits for ecology and conservation. We tested these hypotheses with double-observer aerial surveys of 10 mammal species in northern Botswana. We combined all 10 species and modeled their detectability with species traits (mass, mean herd size, color) as predictors while controlling for observer effects, vegetation, and herd size. We found support for effects of mass and an interaction between herd size and mean herd size on detectability. This model accurately predicted the ratio of herds detected by two observers vs. one observer for 8 of 10 species. To test whether a model based on species traits could be applied to a new species, we serially deleted each species from the data set, fit a trait-based model to the remaining nine species, and used this model to predict detectability for the deleted species. The model was able to reproduce the species-trait model for seven species and accurately predicted the ratio of detections by one or two observers for a different set of seven species; the model was successful by both measures for five species. To our knowledge, this represents the first time that a mechanistic model for detectability of animals has been used to predict detectability for new species. Prediction failed for species with extreme values of traits, suggesting that predicting detectability is not possible near or beyond the boundaries of one's data set. The approach taken in this paper can potentially be used with a variety of taxa and may provide new opportunities to apply detectability corrections where they have not been possible before.


Subject(s)
Ecology/methods , Mammals , Models, Theoretical , Aircraft , Animals , Botswana
11.
Conserv Biol ; 32(3): 672-684, 2018 06.
Article in English | MEDLINE | ID: mdl-29068083

ABSTRACT

Land-use change is the largest proximate threat to biodiversity yet remains one of the most complex to manage. In British Columbia (BC), where large mammals roam extensive tracts of intact habitat, continued land-use development is of global concern. Extant mammal diversity in BC is unrivalled in North America owing, in part, to its unique position at the intersection of alpine, boreal, and temperate biomes. Despite high conservation values, understanding of cumulative ecological impacts from human development is limited. Using cumulative-effects-assessment (CEA) methods, we assessed the current human footprint over 16 regional ecosystems and 7 large mammal species. Using historical and current range estimates of the mammals, we investigated impacts of human land use on species' persistence. For ecosystems, we found that bunchgrass, coastal Douglas fir, and ponderosa pine have been subjected to over 50% land-use conversion, and over 85% of their spatial extent has undergone either direct or estimated indirect impacts. Of the mammals we considered, wolves were the least affected by land conversion, yet all species had reduced ranges compared with historical estimates. We found evidence of a hard trade-off between development and conservation, most clearly for mammals with large distributions and ecosystems with high levels of conversion. Rather than serve as a platform to monitor species decline, we strongly advocate these data be used to inform land-use planning and to assess current conservation efforts. More generally, CEAs offer a robust tool to inform wildlife and habitat conservation at scale.


Subject(s)
Conservation of Natural Resources , Ecosystem , Animals , Biodiversity , British Columbia , Humans , North America
12.
Ecology ; 99(1): 172-183, 2018 Jan.
Article in English | MEDLINE | ID: mdl-29065232

ABSTRACT

Occupancy-abundance (OA) relationships are a foundational ecological phenomenon and field of study, and occupancy models are increasingly used to track population trends and understand ecological interactions. However, these two fields of ecological inquiry remain largely isolated, despite growing appreciation of the importance of integration. For example, using occupancy models to infer trends in abundance is predicated on positive OA relationships. Many occupancy studies collect data that violate geographical closure assumptions due to the choice of sampling scales and application to mobile organisms, which may change how occupancy and abundance are related. Little research, however, has explored how different occupancy sampling designs affect OA relationships. We develop a conceptual framework for understanding how sampling scales affect the definition of occupancy for mobile organisms, which drives OA relationships. We explore how spatial and temporal sampling scales, and the choice of sampling unit (areal vs. point sampling), affect OA relationships. We develop predictions using simulations, and test them using empirical occupancy data from remote cameras on 11 medium-large mammals. Surprisingly, our simulations demonstrate that when using point sampling, OA relationships are unaffected by spatial sampling grain (i.e., cell size). In contrast, when using areal sampling (e.g., species atlas data), OA relationships are affected by spatial grain. Furthermore, OA relationships are also affected by temporal sampling scales, where the curvature of the OA relationship increases with temporal sampling duration. Our empirical results support these predictions, showing that at any given abundance, the spatial grain of point sampling does not affect occupancy estimates, but longer surveys do increase occupancy estimates. For rare species (low occupancy), estimates of occupancy will quickly increase with longer surveys, even while abundance remains constant. Our results also clearly demonstrate that occupancy for mobile species without geographical closure is not true occupancy. The independence of occupancy estimates from spatial sampling grain depends on the sampling unit. Point-sampling surveys can, however, provide unbiased estimates of occupancy for multiple species simultaneously, irrespective of home-range size. The use of occupancy for trend monitoring needs to explicitly articulate how the chosen sampling scales define occupancy and affect the occupancy-abundance relationship.


Subject(s)
Ecology , Ecosystem , Animals
13.
Accid Anal Prev ; 109: 55-61, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29031047

ABSTRACT

Roadside Animal Detection Systems (RADS) aim to reduce the frequency of wildlife-vehicle collisions. Unlike fencing and wildlife passages, RADS do not attempt to keep animals off the road; rather, they attempt to modify driver behavior by detecting animals near the road and warning drivers with flashing signs. A RADS was installed in Big Cypress National Park (Florida, USA) in 2012 in response to an increased number of Florida panther mortalities. To assess driver response, we measured the speed of individual cars on the road when the RADS was active (flashing) and inactive (not flashing) during the tourist season (November-March) and the off-season (April-October), which vary dramatically in traffic volume. We also used track beds and camera traps to assess whether roadside activity of large mammal species varied between seasons. In the tourist season, the activation of the RADS caused a significant reduction in vehicle speed. However, this effect was not observed in the off-season. Track and camera data showed that the tourist season coincided with peak periods of activity for several large mammals of conservation interest. Drivers in the tourist season generally drove faster than those in the off-season, so a reduction in speed in response to the RADS is more beneficial in the tourist season. Because traffic volume and roadside activity of several species of conservation interest both peak during the tourist season, our study indicates that the RADS has the potential to reduce the number of accidents during this period of heightened risk.


Subject(s)
Accidents, Traffic/prevention & control , Animal Welfare , Automobile Driving , Automobiles , Accidents, Traffic/statistics & numerical data , Animals , Coyotes , Deer , Florida , Humans , Lynx , Risk , Seasons , Ursidae
14.
Zookeys ; (613): 1-157, 2016.
Article in English | MEDLINE | ID: mdl-27667928

ABSTRACT

The fluviatile terrace deposits of Khok Sung, Nakhon Ratchasima province, have yielded more than one thousand fossils, making this the richest Pleistocene vertebrate fauna of Thailand. The excellent preservation of the specimens allows precise characterization of the faunal composition. The mammalian fauna consists of fifteen species in thirteen genera, including a primate, a canid, a hyaenid, proboscideans, rhinoceroses, a suid, cervids, and bovids. Most species correspond to living taxa but globally (Stegodon cf. orientalis) and locally (Crocuta crocuta ultima, Rhinoceros unicornis, Sus barbatus, and Axis axis) extinct taxa were also present. The identification of Axis axis in Khok Sung, a chital currently restricted to the Indian Subcontinent, represents the first record of the species in Southeast Asia. Three reptilian taxa: Crocodylus cf. siamensis, Python sp., and Varanus sp., are also identified. Faunal correlations with other Southeast Asian sites suggest a late Middle to early Late Pleistocene age for the Khok Sung assemblage. However, the Khok Sung mammalian fauna is most similar to that of Thum Wiman Nakin, dated to older than 169 ka. The Khok Sung large mammal assemblage mostly comprises mainland Southeast Asian taxa that migrated to Java during the latest Middle Pleistocene, supporting the hypothesis that Thailand was a biogeographic pathway for the Sino-Malayan migration event from South China to Java.

15.
J Hum Evol ; 95: 1-12, 2016 06.
Article in English | MEDLINE | ID: mdl-27260171

ABSTRACT

The dispersal of Homo erectus out of Africa at some 1.9 million years ago is one of the most important, crucial, and yet controversial events in human evolution. Current opinions about this episode expose the contrast between those who see H. erectus as a highly social, cooperative species seeking out new ecological opportunities to exploit, and those preferring a passive, climate driven explanation for such an event. By using geostatistics techniques and probabilistic models, we characterised the ecological context of H. erectus dispersal, from its East African origin to the colonization of Eurasia, taking into account both the presence of other large mammals and the physical characteristics of the landscape as potential factors. Our model indicated that H. erectus followed almost passively the large herbivore fauna during its dispersal. In Africa, the dispersal was statistically associated with the presence of large freshwater bodies (Rift Valley Lakes). In Eurasia, the presence of H. erectus was associated with the occurrence of geological outcrops likely yielding unconsolidated flint. During the early phase of dispersal, our model indicated that H. erectus actively avoided areas densely populated by large carnivores. This pattern weakened as H. erectus dispersed over Europe, possibly because of the decreasing presence of carnivores there plus the later acquisition of Acheulean technology. During this later phase, H. erectus was associated with limestone and shaley marl, and seems to have been selecting for high-elevation sites. While our results do not directly contradict the idea that H. erectus may have been an active hunter, they clearly point to the fact that predator avoidance may have conditioned its long-distance diffusion as it moved outside Africa. The modelled dispersal route suggests that H. erectus remained preferentially associated with low/middle latitude (i.e., comparatively warm) sites throughout its colonization history.


Subject(s)
Animal Distribution , Biological Evolution , Hominidae/physiology , Africa , Animals , Human Migration , Models, Biological
16.
J Anim Ecol ; 85(4): 857-68, 2016 07.
Article in English | MEDLINE | ID: mdl-27007672

ABSTRACT

Indirect effects of large mammalian herbivores (LMH), while much less studied than those of apex predators, are increasingly recognized to exert powerful influences on communities and ecosystems. The strength of these effects is spatiotemporally variable, and several sets of authors have suggested that they are governed in part by primary productivity. However, prior theoretical and field studies have generated conflicting results and predictions, underscoring the need for a synthetic global analysis. We conducted a meta-analysis of the direction and magnitude of large mammalian herbivore-initiated indirect interactions using 67 published studies comprising 456 individual responses. We georeferenced 41 of these studies (comprising 253 responses from 33 locations on five continents) to a satellite-derived map of primary productivity. Because predator assemblages might also influence the impact of large herbivores, we conducted a similar analysis using a global map of large carnivore species richness. In general, LMH reduced the abundance of other consumer species and also tended to reduce consumer richness, although the latter effect was only marginally significant. There was a pronounced reduction in the strength of negative (i.e. suppressive, due e.g., to competition) indirect effects of LMH on consumer abundance in more productive ecosystems. In contrast, positive (facilitative) indirect effects were not significantly correlated with productivity, likely because these comprised a more heterogeneous array of mechanisms. We found no effect of carnivore species richness on herbivore-initiated indirect effect strength. Our findings help to resolve the fundamental problem of ecological contingency as it pertains to the strength of an understudied class of multitrophic interactions. Moreover, these results will aid in predicting the indirect effects of anthropogenic wildlife declines and irruptions, and how these effects might be mediated by climatically driven shifts in resource availability. To the extent that intact ungulate guilds help to suppress populations of small animals that act as agricultural pests and disease reservoirs, the negative impacts of large mammal declines on human well-being may be relatively stronger in low-productivity areas.


Subject(s)
Food Chain , Herbivory , Plant Physiological Phenomena , Animals , Carnivory , Ecosystem , Mammals
17.
Ecology ; 97(4): 1058-1068, 2016 Apr.
Article in English | MEDLINE | ID: mdl-28792596

ABSTRACT

Autumn has to a large extent been neglected in the climate effect literature, yet autumn events, e.g., plant senescence and animal migration, affect fitness of animals differently than spring events. Understanding how variables including plant phenology influence timing of autumn migrations is important to gain a comprehensive understanding of the full annual cycle of migratory species. Here we use 13 yr of data from 60 male and 168 female red deer (Cervus elaphus) to identify triggers of autumn migration. We relate the timing of autumn migration to environmental variables like snow fall, temperature, and plant phenology (NDVI), and to onset of hunting, sex, and migration distance. Severe weather has been suggested as the main trigger of autumn migration, but we found that the majority of the individuals had left the summer range well before snow fall (80.3%) and frost (70.5%), and also before the peak deterioration in forage quality (71.9%). Declining temperatures were associated with a higher daily migration potential. Onset of hunting showed the largest effect on migration potential, with a marked increase during the first days of hunting. Individuals still present in the summer range when snow fall, frost, or peak forage deterioration occurred showed a significantly higher migration potential around these events. Males were less responsive to environmental cues, suggesting rutting activity, starting earlier in males, initiate movement prior to such conditions. Also, individuals with longer migration distances had a higher migration potential late in the season than individuals with shorter migration distances. Our study shows that factors beyond weather and plant phenology, such as onset of hunting, may be important triggers of autumn migration. Severe weather and forage deterioration were important triggers for the individuals experiencing this, which suggests a hierarchical response to environmental cues. The trade-off between staying longer in the summer range and increased energy expenditures if surprised by severe weather is asymmetric, and leaving well in advance can be seen as a risk-averse tactic.


Subject(s)
Animal Migration , Deer/physiology , Environmental Monitoring , Animals , Climate , Female , Male , Seasons , Snow
18.
Biota neotrop. (Online, Ed. port.) ; 15(4): 1-11, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-762897

ABSTRACT

At least 251 mammal species are recorded for the Brazilan cerrado, which, therefore, is the third richest Brazilian biome. Most mammal surveys in Brazilian cerrado result from studies performed opportunistically and in short time periods. The aims of the present study were (1) provide a checklist for the mammalian fauna based on a five-year sampling in Serra do Facão region, Southeastern Goiás state; (2) compare small non-flying mammals diversity in open and forest areas and (3) compare species diversity before and after the flood caused by a hydroelectric reservoir filling. The data was gathered in 19 sampling periods, from May 2008 to September 2013. We sampled open and forest habitats and captured non-flying small mammals with Sherman and Tomahawk live traps and pitfalls; bats were sampled with mist-nets; large mammals were recorded with camera traps, and by direct observations and track surveys in field. We found 20 species of small non-flying mammals, 10 species of bats and 33 species of larger mammals. Species diversity was greater for forest than open habitats, and was also greater before than after the complete reservoir filling. About 10% of the recorded species are included in the Brazilian official list of threatened species. The total richness represents 25% of all cerrado mammal fauna, highlighting the importance of this area for regional mammal fauna conservation.


Há 251 espécies de mamíferos de ocorrência confirmada no cerrado, o terceiro bioma brasileiro em riqueza de espécies. A maioria dos inventários da mastofauna do cerrado é resultado de estudos oportunísticos, com curta duração. Os objetivos do presente estudo foram (1) inventariar a mastofauna durante cinco anos de amostragens na região do Aproveitamento Hidrelétrico da Serra do Facão, no sudeste do estado de Goiás; (2) Comparar a diversidade de pequenos mamíferos em áreas abertas e florestais e (3) comparar a diversidade da mastofauna antes e depois da inundação causada pelo enchimento do reservatório do empreendimento hidrelétrico. A coleta de dados foi realizada em 19 campanhas de amostragem, entre maio de 2008 e setembro de 2013. Os pequenos mamíferos não voadores foram amostrados com armadilhas Sherman e Tomahawk, e armadilhas de queda; morcegos foram amostrados com redes de neblina; e os mamíferos de maior porte foram amostrados com armadilhas-fotográficas, observações diretas e observações de vestígios. Foram registradas 20 espécies de pequenos mamíferos não-voadores, 10 espécies de morcegos e 33 de mamíferos de maior porte. A diversidade de pequenos mamíferos não voadores foi maior em ambientes florestais que em abertos, e foi também maior antes do que depois do enchimento do reservatório da hidroelétrica. Cerca de 10% das espécies registradas estão incluídas na lista oficial dos mamíferos ameaçados de extinção. O total de espécies representa 25% da fauna de mamíferos do cerrado, o que demonstra a importância da área para conservação da mastofauna regional.

20.
Biota neotrop. (Online, Ed. port.) ; 11(1): 313-328, jan.-mar. 2011. graf, mapas, tab
Article in Portuguese | LILACS | ID: lil-599705

ABSTRACT

A comunidade de mamíferos terrestres foi amostrada em três localidades (1-Mateiros, TO; 2- Rio da Conceição, TO e 3- Formosa do Rio Preto, BA) no interior da Estação Ecológica Serra Geral do Tocantins. Para o registro dos marsupiais e pequenos roedores foram utilizadas armadilhas convencionais (5.396 armadilhas.noite) e armadilhas de queda (5.300 pitfalls.noite) nas diferentes fitofisionomias encontradas, entre elas: campo úmido, campo limpo, campo sujo, campo cerrado, cerrado sensu stricto, cerrado com afloramentos rochosos, mata de galeria e mata de galeria úmida. No caso dos mamíferos de médio e grande porte, foram obtidos registros casuais através de observação direta e evidências indiretas (rastros, fezes, crânios e carcaças de animais encontrados mortos). Foram amostradas 24 espécies de pequenos mamíferos e 17 espécies de mamíferos de médio e grande porte, totalizando 41 espécies para a região. Considerando-se os pequenos mamíferos, a comunidade foi representada por várias espécies raras e de abundância intermediária, e poucas espécies muito abundantes. Os roedores cricetídeos dominaram tanto em número de espécies (14) quanto em abundância (50 por cento da comunidade). As espécies se distribuíram, basicamente, em dois tipos de fisionomias: um grupo esteve restrito aos ambientes florestais, e outro às formações abertas, demonstrando a grande seletividade de hábitats e a importância de se amostrar o mosaico de hábitats presente na região para uma melhor caracterização da diversidade deste grupo de mamíferos. Em termos biogeográficos, a fauna de pequenos mamíferos amostrada apresentou certa sobreposição com a fauna da Caatinga e da Amazônia, evidenciando a importância destes domínios para a composição de espécies das comunidades que habitam a porção norte do Cerrado, além da presença de espécies endêmicas e de distribuição geográfica restrita ao norte do domínio, caracterizando uma comunidade distinta de outras regiões do Cerrado. Em relação aos mamíferos de médio e grande porte, a presença de um elevado número de espécies ameaçadas de extinção (10) também ressalta a importância da preservação desta região.


The terrestrial mammal community was surveyed along three distinct localities (1-Mateiros, TO; 2- Rio da Conceição, TO e 3- Formosa do Rio Preto, BA) in the Estação Ecológica Serra Geral do Tocantins. The small non-volant mammals were recorded by the use of conventional live traps (5,396 trap.nights) and pitfall traps (5,300 trap.nights) in the different physiognomies found, such as: "campo úmido", "campo limpo", "campo sujo", "campo cerrado", "cerrado sensu stricto", "cerrado sensu stricto with rocks", gallery forest and wet gallery forest. The large mammals were casually registered by visual or indirect evidences (tracks, feces, carcasses). We recorded 24 small non-volant mammals and 17 large mammals, totalizing 41 species for this region. The small mammal community was characterized by several rare and intermediate in abundance species, and few species very abundant. Rodents from the family Cricetidae dominated both in number of species (14) as in number of individuals (50 percent of the community). The species segregated among the forested and open formations, showing the great habitat selectivity and the importance to survey the habitat mosaic to characterize the diversity of this mammal group. The small non-volant mammal fauna surveyed showed some overlap with the fauna from the Caatinga and Amazon biomes, demonstrating the importance of these biomes in the faunal composition of the communities localized in the northern portion of the Cerrado. In addition, we also recorded endemic species and species with a restricted distribution to this north portion, characterizing a distinct community within the Cerrado. The large mammal community was characterized by a high number of threatened species (10), increasing the importance of this region in preserving the fauna of the northern portion of the Cerrado.

SELECTION OF CITATIONS
SEARCH DETAIL
...