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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Spatial relational learning and foraging in cotton-top tamarins

Dolins, Francine Leigh January 1993 (has links)
Spatial relationalleaming can be defined as the use of the spatial (geometric) relationship between two or more cues (landmarks) in order to locate additional points in space (O'Keefe and Nadel, 1979). An internal spatial representation enables an animal to compute novel locations and travel routes from familiar landmarks and routes (Dyer, 1993). A spatial representation is an internal construct mediating between perceived stimuli in the environment and the behaviour of the animal (Tolman, 1948). In this type of spatial representation the information encoded must be isomorphic with the physical environment such that the geometric relations of distance, angle and direction are maintained or can be computed from the stored information (Gallistel, 1990). A series of spatial and foraging task experiments were conducted to investigate the utilisation of spatial relational learning as a spatial strategy available to cotton-top tamarins (Sag uinus oedipus oedipus). The apparatus used was an 8x8 matrix of holes set in an upright wooden board to allow for the manipulation of visual cues and hidden food items such that the spatial configuration of cues and food could be transformed (translated or rotated) with respect to the perimeter of the board. The definitive test of spatial relational learning was whether the monkeys relied upon the spatial relationship between the visual cues to locate the position of the hidden food items. In a control experiment testing for differential use of perceptual information the results showed that if given the choice, tamarins relied on visual over olfactory cues in a foraging task. Callitrichids typically depend on olfactory communication in socio-sexual contexts so it was unusual that olfaction did not also play a significant role in foraging. In the first spatial learning experiment, the tamarins were found to rely on the three visually presented cues to locate the eleven hidden food items. However, their performance was not very accurate. In the next experiment the task was simplified so that the types of spatial strategies the monkeys were using to solve the foraging task could be clearly identified. In this experiment, only two visual cues were presented on either end of a line of four hidden food items. Once the monkeys were trained to these cues, the cues and food were translated and/or rotated on the board. Data from the beginning and middle of each testing session were used in the final analysis: in a previous analysis it was found that the monkeys initially searched the baited holes in the beginning of a testing session and thereafter predominantly searched unbaited holes. This suggests that they followed a win-stay/lose-shift foraging strategy, a finding that is supported by other studies of tamarins in captivity (Menzel and Juno, 1982) and the wild (Garber, 1989). The results also showed that the monkeys were searching predominately between the cues and not outside or around of them, indicating that they were locating the hidden food by using the spatial relationship between the visual cues. This provides evidence for the utilisation of spatial relational learning as a foraging strategy by cotton-top tamarins and the existence of complex internal spatial representations. Further studies are suggested to test captive monkeys' spatial relational capabilities and their foraging strategies. In addition, comparative and field studies are outlined that would provide information regarding New World monkeys' spatial learning abilities, neurophysiological organisation and the evolution of complex computational processes.
2

Seed dispersal ecology of Leonia cymosa (Violaceae) in the rain forest of Eastern Ecuador

Pfrommer, Albrecht January 2009 (has links)
Würzburg, Univ., Diss., 2009. / Zsfassung in dt. Sprache.
3

Collar-Integrated Small Mammal GPS Tracker

Kundu, Ina, Rice, Sean, Klug, Kevin, Chen, Hao, Marquez, Elizabeth, Zhong, Yizhou 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / A position beaconing system for tracking small mammals, such as the Golden Lion Tamarin, was developed and tested. GPS acquires location of the animal. The system utilizes a VHF radio transmitter tuned to 144.390 MHz, which is located in the amateur radio band. APRS was selected as the protocol for position, transmission, and recovery. This allows users to benefit from any existing APRS enabled devices. The beacon was designed by attempting to optimize operational longevity and minimize size. Consequently, the system is implemented on a single board and enclosed for protection. As the system must be comfortable for the mammal, it was manufactured from lightweight components and enclosed in a plastic housing. To attach the case to the mammal, it is connected to a flexible, zig-zag, wearable antenna, which functions as a collar.
4

Developing saddleback and emperor tamarin SNP set for in situ genotyping

López Clinton, Samantha January 2022 (has links)
Many countries in the global south - which harbour the majority of the world’s biodiversity - face serious resource limitations and a lack of access to affordable sequencing services. Furthermore, biodiversity research and monitoring of non-model, threatened and/or cryptic species often relies on low-quality non-invasive genetic samples. In situ conservation genomics approaches optimised for field conditions and low-quality DNA can help empower local researchers and meet their needs. To do so, however, accessible and reproducible sequencing and genotyping alternatives are needed. I designed a SNP panel as a field-friendly genotyping approach for two species of Amazonian primates using both high- and low-quality DNA samples, and two different sequencing platforms, Illumina and Nanopore. I used 14 high-quality genomes to identify a set of 210 SNPs that allow for identification of species (twelve SNPs), sex (twelve SNPs) and individual identity (186 SNPs) in two species of tamarins, Leontocebus weddelli and Saguinus imperator. Primers, adapters and indexes were designed in a Genotyping-in-Thousands by sequencing approach that is compatible with both sequencing platforms. This approach is based on sequencing multiplexed PCR products of a few hundred target SNPs to genotype thousands of individuals in a single sequencing run. In an effort to make conservation genomics more accessible, the reproducible pipeline to obtain the informative SNPs is being modulated with Snakemake, a workflow management system. / Muchos países en el sur global - los cuales poseen la mayoría de la biodiversidad mundial - enfrentan serias limitaciones de recursos y una falta de acceso a servicios económicos de secuenciación. Con frecuencia, la investigación y el monitoreo de biodiversidad y especies no-modelo, amenazadas y/o crípticas, dependen de muestras genéticas no-invasivas de baja calidad. La genómica de la conservación in situ optimizada para condiciones de campo y ADN de baja calidad puede empoderar a investigadorxs locales y ayudarles a responder a sus necesidades. Para ello, sin embargo, se requieren alternativas accesibles y reproducibles de secuenciación y genotipado. Diseñé un panel de SNPs como una aproximación de genotipado apta para el campo y dirigida a dos especies de primates amazónicos con el uso de ADN de baja y alta calidad, y dos plataformas de secuenciación (Illumina y Nanopore). Usé 14 genomas de alta calidad para encontrar 210 SNPs que permiten la identificación de la especie (doce SNPs), del sexo (doce SNPs) y de la identidad individual (186 SNPs) en dos especies de pichicos, Leontocebus weddelli y Saguinus imperator. Los cebadores, adaptadores e índices fueron diseñados con un enfoque de Genotyping-in-Thousands by sequencing (Genotipado en los miles por secuenciación) que es compatible con ambas plataformas de secuenciación. Este método está basado en la secuenciación de productos de PCR multiplexados de unos cientos de SNPs para genotipar miles de individuos en una sola corrida de secuenciación. En un intento de mejorar la accesibilidad de la genómica de la conservación, el proceso reproducible para obtener a los SNPs informativos está siendo modulado con Snakemake, un sistema de manejo de flujos de trabajo.
5

Formal security analysis of authentication in an asynchronous communication model / Formell säkerhetsanalys av autentisering i en asynkron kommunikationsmodell

Wahlgren, Jacob, Yousefzadegan Hedin, Sam January 2020 (has links)
Formal analysis of security protocols is becoming increasingly relevant. In formal analysis, a model is created of a protocol or system, and propositions about the security of the model are written. A program is then used to verify that the propositions hold, or find examples of where they do not. This report uses formal methods to analyse the authentication aspect of a protocol that allows private individuals, enterprises, and systems to securely and asynchronously share sensitive data. Unpublished, early drafts of the protocol were studied and algorithms described in it were verified with the help of the formal verification tool Tamarin Prover. The analysis revealed two replay attacks. Improvements to the protocol were suggested based on this analysis. In later versions of the protocol, the improvements have been implemented by the protocol developers. / Det blir alltmer relevant med formell analys av säkerhetsprotokoll. I formell analys så skapas en modell av ett protokoll eller ett system, och påståenden om modellens säkerhet skrivs. Ett program används sedan för att verifiera att påståendena gäller, eller för att hitta exempel där de inte gäller. Den här rapporten avänder formella metoder för att analysera autentiseringsaspekten av ett protokoll som tillåter privatpersoner, företag och system att asynkront dela känslig information på ett säkert sätt. Opublicerade och tidiga utkast av protokollet studerades och de algoritmer som beskrivs i protokollet verifierades med hjälp av Tamarin Prover. Analysen avslöjade två återspelningsattacker. Förbättringar till protokollet föreslogs baserat på denna analys. I senare versioner har protokollutvecklarna implementerat förslagen.
6

Seed dispersal ecology of Leonia cymosa (Violaceae) in the rain forest of Eastern Ecuador / Ökologie der Ausbreitung der Samen von Leonia cymosa (Violaceae) im Regenwald von Ost-Ekuador

Pfrommer, Albrecht January 2009 (has links) (PDF)
Leonia cymosa (Violaceae) ist ein Baum der unteren Waldschicht im Amazonischen Regenwald. Meine Probenflächen befanden sich in der „Reserva Faunistica Cuyabeno“ im nord-östlichen Ecuador: Meine Untersuchung hatte das Ziel, die Variation von Baummerkmalen zu beschreiben und zu klären, ob und wie die Fruchtentnahme aus den einzelnen Bäumen durch Fruchtfresser mit den Baummerkmalen zusammenhängt. Die mittlere Höhe einer fruchttragenden L. cymosa war 6,6 m (Min. 2 m, Max. 12,6 m). Der Median der Individuendichte lag bei 11,8 Bäumen pro Hektar. Die Bäume wuchsen überwiegend in Gruppen, die aus Bäumen verschiedener Höhe bestanden. L. cymosa blühte zwei Mal im Jahr, sowohl im späten Februar bis März, als auch im Oktober. Die daraus jeweils folgenden Fruchtsaisons erstreckten sich auf die Monate August/September und März bis Mai. Das Fruchtfleisch von L. cymosa enthielt die Zucker Fruktose, Glucose und Saccharose, Proteine, aber keine Lipide. Es gab es signifikante Unterschiede zwischen Bäumen bei allen untersuchten Nährstoffbestandteilen. Die saisonale Produktivität der überwachten Bäume lag im Median bei 45 (1999, n= 57) bzw. bei 36 (2000, n=92) reifen Früchten. Das maximale Fruchtangebot eines Baumes zum Zeitpunkt einer Fruchtzählung lag bei 324 reifen Früchten Schwarzrückentamarine (Saguinus nigricollis, Callitrichidae) und Totenkopfäffchen (Saimiri sciureus, Cebidae), sowie möglicherweise eine unidentifizierte nachtaktive Tierart, konsumierten die Früchte von L. cymosa in meinem Untersuchungsgebiet. Früchte, die von den Bäumen auf den Boden herabgefallen waren, wurden von Grünen Zwergagutis (Myoprocta pratti, Dasyproctidae) gefressen. Schwarzrückentamarine und Totenkopfäffchen unterschieden sich stark in ihrer Effektivität als Samenausbreiter. Schwarzrückentamarine waren zuverlässige Ausbreiter, Totenkopfäffchen nicht. Jede meiner Studienflächen war Teil des Kern-Wohngebietes von jeweils einer Gruppe von Schwarzrückentamarinen, und fiel in das Streifgebiet einer Gruppe von Totenkopfäffchen. In einer Stichprobe von 6 Bäumen vergleichbarer und hoher saisonaler Fruchtproduktion war die Gesamtanzahl an reifen Früchten eines jeweiligen Baums, die durch den zuverlässigen Samenausbreiter S. nigricollis im Verlauf einer Fruchtsaison geerntet wurden, mit keinem der gemessenen Nährstoffbestandteile des Fruchtfleischs signifikant korreliert. Der zuverlässige Samenausbreiter von L. cymosa scheint keinen Selektionsdruck auf den Nährstoffgehalt der Früchte von L. cymosa auszuüben. Die saisonale Fruchtproduktion eines L. cymosa -Baums war die hauptsächliche Vorhersagevariable für alle Aspekte der Fruchtentnahme durch den effektiven Samenausbreiter, Saguinus nigricollis, sowie auch durch den Nicht-Samenausbreiter, Saimiri sciureus. Bäume mit größerer saisonaler Fruchtproduktion hatten eine höhere Wahrscheinlichkeit der Fruchtentnahme durch den Samenausbreiter als Bäume mit kleinerer saisonaler Fruchtproduktion. Von Bäumen mit größerer saisonaler Fruchtproduktion ernteten die Samenausbreiter ebenfalls mehr Früchte. Diese Bäume hatten also einen größeren Ausbreitungserfolg. Der prozentuale Anteil der vom Samenausbreiter entnommenen Früchte an der gesamten saisonalen Fruchtproduktion eines Baums sank jedoch mit wachsender Fruchtproduktion. Im Gegensatz dazu stieg der prozentuale Anteil der vom Nicht-Samenausbreiter abgeernteten Früchte an der gesamten saisonalen Fruchtproduktion mit größer werdender saisonaler Fruchtproduktion. Ebenso stieg die Wahrscheinlichkeit der Fruchtentnahme durch den Nicht-Samenausbreiter und die Anzahl der von ihm geernteten Früchte mit größer werdender saisonaler Fruchtproduktion. Die beobachteten Unterschiede zwischen Samenausbreiter und Nicht-Samenausbreiter sind auf Unterschiede in der jeweiligen Nahrungsaufnahmekapazität, der Gruppengröße und des Fouragierverhaltens zurückzuführen. Tamarine ernteten mit geringerer Wahrscheinlichkeit L. cymosa Bäume, die nicht oder nur wenig von umgebender Vegetation gedeckt waren. Dies reflektiert wahrscheinlich ein Verhalten der Tamarine zur Vermeidung von Angriffen von Wald-Raubvögeln. Bei hoher Dichte von L. cymosa-Früchten in der Nachbarschaft einzelner Bäume verringerte sich der Anteil der Früchte an der saisonalen Fruchtproduktion, die von Tamarinen geerntet wurden. Dies spricht für Konkurrenz von Bäumen um Samenausbreiter. Meine Studie hat Selektionsdrücke der Samenausbreiter auf die saisonale Fruchtproduktion von L. cymosa aufgedeckt. Meine Ergebnisse bestätigen die Vorhersagen der „fruit crop size-Hypothese“. Meine Ergebnisse zeigen ebenfalls, dass es auch Faktoren außerhalb der Kontrolle eine Baumindividuums gibt, die die Fruchtentnahme von L. cymosa Bäumen beeinflussen. Selektion durch Samenausbreiter könnte durch Nachbarschaftsbedingungen begrenzt. / Leonia cymosa (Violaceae) is a small tree from the under story of the Amazonian rain forest. I investigated the seed dispersal ecology of L. cymosa in plots of old growth terra firme forest located within the Cuyabeno Faunistic Reserve in north-eastern Ecuador. This species offered good conditions to examine the variation of traits of individual trees and the way they are linked with fruit removal from each tree. With this study I aimed to address the question whether frugivores exert selection pressures on fruits and the fruiting regime of fleshy fruited plants. The mean height of a fruiting L. cymosa was 6.6 m (range: 2 - 12.6 m). The median tree density was 11.8 trees per hectare. Trees grew in clusters consisting of different numbers of trees of different heights. L. cymosa flowered two times a year, in late February to March and in October. The respective fruiting seasons occurred in August/September and between March and May. The fruit pulp of L. cymosa contained the sugars fructose, glucose, and sucrose, the total soluble sugar being the first important nutritional compound of the fruit pulp. The second important compound was proteins. No lipids were found in the fruit pulp. The variation of nutritional quality of the fruits was high within trees. Nonetheless, significant differences were found among trees in all nutrient constituents studied. The maximum of ripe fruits produced per season by a single tree was 427. Median productivity of the trees was 45 ripe fruits throughout the fruiting season in 1999 (n=57) and 36 ripe fruits in 2000 (n=92). The maximum standing crop of fruits in a tree was 324 fruits (counted in 2000). Black mantle tamarins, Saguinus nigricollis (Callitrichidae), and squirrel monkeys, Saimiri sciureus (Cebidae), and possibly an unknown nocturnal frugivore consumed the fruits of L. cymosa at my study site. Green-rumped acouchis (Myoprocta pratti, Dasyproctidae) consumed fallen fruits and seeds underneath the trees. Black mantle tamarins and squirrel monkeys differed widely in their effectiveness as seed dispersers. Black mantle tamarins swallowed the seeds together with the fruit pulp and defecated intact seeds far away from the mother tree. Squirrel monkeys opened the fruits to suck and gnaw on the fruit pulp, and then dropped seeds to the forest floor below the tree crowns. Each of my study plots fell into the core home range of one group each of S. nigricollis and S. sciureus. Thus, the frugivore assemblage is small and disperser availability is limited for the individual tree of L. cymosa. In a sample of 6 trees of comparable and high fruit crop size, the total of ripe fruits removed from a tree throughout the whole fruiting season by the reliable seed disperser S. nigricollis was neither significantly correlated with the content of any of the nutrients measured in the fruit pulp (fructose, glucose, sucrose, total protein; pulp does not contain lipids), nor with total metabolisable energy, seed to pulp weight ratio, or water content of the fruit pulp. Feeding preferences for single sugars determined by other laboratory studies were not confirmed by this field study. The reliable seed disperser S. nigricollis does not seem to exert selective pressure on the nutrient content of the fruits of L. cymosa. Seasonal fruit crop size was the main predictor of all aspects of fruit removal by the effective disperser of L. cymosa, Saguinus nigricollis, as well as by the non-disperser, Saimiri sciureus. Trees with larger seasonal fruit crop size had a higher probability to have fruits removed by the disperser than those with small seasonal fruit crop sizes. They also had a higher number of fruits removed by the seed disperser. However, the proportion of fruits removed by the disperser decreased with increasing seasonal fruit crop size. In contrast, probability of fruit removal, the number of fruits removed, and the proportion of fruits removed by the non-disperser increased with increasing seasonal fruit crop sizes. The observed differences between disperser and non-disperser are due to differences in feeding capacity, group size and foraging behavior. Tamarins were less likely to harvest Leonia trees that were not or less completely covered by surrounding vegetation. This probably reflects a behavior to avoid predation by forest raptors. At high con-specific fruit abundance in the neighborhood, the proportion of fruits removed by tamarins was reduced. This suggests competition of trees for the disperser. My study revealed selection of the disperser on seasonal fruit crop size of L. cymosa. My results are consistent with the “fruit crop size hypothesis”. FCSH appears to constitute a valid framework also in the monkey-dispersed L. cymosa. My findings also show that factors beyond the tree’s control influenced fruit removal from Leonia trees. Disperser-mediated selection may be constrained (yet not impeded) by neighborhood conditions.
7

Influência da paisagem e das características locais na ocorrência do Mico-Leão-Preto (Leontopithecus Chrysopygus, Callitrichidae) / Influence of the landscape and characteristics of the area on the occurrence of the Black Lion Tamarin (Leontopithecus Chrysopygus, Callitrichidae)

Pinto, Bruna Lopes [UNESP] 02 June 2017 (has links)
Submitted by BRUNA LOPES PINTO null (brunalopes111@gmail.com) on 2017-08-02T13:08:31Z No. of bitstreams: 1 Bruna_Lopes Pinto_defesa de mestrado.pdf: 1828198 bytes, checksum: f87153ba517dc4a0051e0058362a5ed3 (MD5) / Rejected by Luiz Galeffi (luizgaleffi@gmail.com), reason: Solicitamos que realize uma nova submissão seguindo a orientação abaixo: O arquivo submetido está sem a ficha catalográfica e sem o certificado de aprovação. O número do processo FAPESP deve constar nos agradecimentos da dissertação/tese. A versão submetida por você é considerada a versão final da dissertação/tese, portanto não poderá ocorrer qualquer alteração em seu conteúdo após a aprovação. Corrija esta informação e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2017-08-03T17:34:36Z (GMT) / Submitted by BRUNA LOPES PINTO null (brunalopes111@gmail.com) on 2017-08-12T19:37:28Z No. of bitstreams: 1 Bruna_Lopes Pinto_defesa_mestrado.pdf: 2556419 bytes, checksum: a7f4d02a3a6803b418af5a8a09394fc8 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-08-18T18:55:19Z (GMT) No. of bitstreams: 1 pinto_bl_me_rcla.pdf: 2556419 bytes, checksum: a7f4d02a3a6803b418af5a8a09394fc8 (MD5) / Made available in DSpace on 2017-08-18T18:55:19Z (GMT). No. of bitstreams: 1 pinto_bl_me_rcla.pdf: 2556419 bytes, checksum: a7f4d02a3a6803b418af5a8a09394fc8 (MD5) Previous issue date: 2017-06-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O bioma Mata Atlântica possui alta diversidade de primatas e com alto grau de endemismo, porém grande parte desses primatas estão ameaçados devido à grande modificação da paisagem. O mico-leão-preto (Callitrichidae, Leontopithecus chrysopygus) é uma espécie endêmica do Estado de São de Paulo, ameaçada de extinção, que ocorre na Mata Atlântica e cuja detecção é difícil por ser de pequeno porte, críptico e ocorrer em baixa densidade. Para poder implementar programas de conservação eficazes, é necessário o conhecimento das áreas de ocorrência da espécie assim como das características ambientais que favorecem sua ocupação. Este trabalho tem como objetivo determinar as características da paisagem e locais que influenciam a ocupação e detecção do mico-leão preto. Através do playback, foi realizado o levantamento dos micos-leões-pretos em 16 sítios amostrais, com 3 pontos em cada um e 3 repetições (uma por mês, Maio-Julho de 2016). Coletamos dados sobre as características locais (largura dos pontos amostrais, diâmetro à altura do peito das árvores, estratificação e presença de gado) e da paisagem (conectividade funcional, quantidade de densidade de borda, cobertura vegetal, tipo de matriz e distância à Estação Ecológica de Angatuba) em cada ponto amostral. As características foram obtidas através dos programas ArcGis, Grass e Google Earth Pro, além da ajuda de um botânico para algumas características locais. O modelo de ocupação (verossimilhança), através da análise de padrão-de única estação (standard-singleseason) pelo programa PRESENCE ® versão 11.8, foi utilizado para encontrar as características que melhor explicam a ocupação e detecção do mico-leão-preto. A ocupação foi de 26% e a detecção de 75%. As características da paisagem foram as que influenciaram tanto na ocupação quanto na detecção. A ocupação dos micos-leões-pretos foi associada à quantidade de áreas florestais, que obteve uma relação positiva, a mesma também encontrada para a detectabilidade. Todavia, a detecção apresentou outra característica (quantidade de densidade de borda), que em lugares mais alterados (com efeito de borda) podem apresentar uma vantagem em relação à locais mais conservados (mais fechados), auxiliando na propagação do som e facilitando a procura do mico no campo. Assim, ao identificar as principais características que influenciam a ocupação dos micos-leões-pretos, outros locais podem ser estimados e as áreas florestais priorizadas e com as medidas mitigadoras mais direcionadas para a preservação e conservação da espécie juntamente com seus hábitats. / The Atlantic Forest biome presents high primate diversity and high degree of endemism, but most of these primates are threatened habitat fragmentation. The black lion tamarin (Callitrichidae, Leontopithecus chrysopygus) is an endemic species of the State of São Paulo, threatened with extinction, occurring in the Atlantic Forest and whose detection is difficult because it is small, cryptic and occurs in low density. In order to implement effective conservation programs, it is necessary to know the areas of occurrence of the species as well as the environmental characteristics that favor their presence. This work aims to determine local and landscape characteristics that influence the occupancy and detection of the black lion tamarin. We used the playback methodology to find the primates in 16 sites samples with 3 points in each and 3 replicates (one per month, May-July 2016). It was collect data from local (width of sampling points, diameter at breast height, stratification and presence of cattle) and landscape characteristics (functional connectivity, amount of border density, vegetation cover, type of matrix and distance to the Ecological Station of Angatuba) at each sampling point. The characteristics were from ArcGis, Grass and Google Earth Pro software, and also from a botanist. The occupation model (likelihood), through standard-single-season (standardsingle-season) using the PRESENCE ® version 11.8 software, helped to find which characteristics best explain the occupation and detection of the black lion tamarin. The occupation was 26% and the detection was 75%. The characteristics of the landscape were those that influenced both (occupation and detection). The occupation of the black lion tamarins was associated to the number of forest areas, which obtained a positive relation, the same also it was find for detectability. However, the detection presented another characteristic (amount of edge density), which shows that in more altered sites (with border effect) can present an advantage over the more conserved (more closed) sites, helping the propagation of the sound and facilitating the search of the black lion tamarin in the field. Thus, identifying the main characteristics that influence the occupation of black lion tamarins, other sites can be estimate, forest areas can be prioritized and mitigating measures for the preservation and conservation of the species along with their habitats. / FAPESP: 2014/14739-0
8

Home range- and behavioural analysis of the Saddleback tamarin (Leontocebus fuscicollis) in Madre de Dios, Peru

Nymark, Marianne Kristine January 2023 (has links)
60% of primates in the world are threatened with extinction, while 75% have declining populations. The biggest threats to primates are the result of human activity. In this study, I have been looking at the primate Spix’s Saddleback tamarin (Leontocebus fuscicollis) and tried to estimate the home range size of four different study groups, while also trying to assess if there are differences in the type of trees in the areas where the tamarins are present compared to where they are absent. I have also compared the behaviour of the four different study groups. The data was collected in the Tambopata nature reserve in the Madre de Dios region in Peru during the summer of 2022, with the help and support from the research organisation Fauna Forever. To complement the observations, previously collected data from 2019-2021 was also used. The tamarins were followed using a group follow method, and the behaviour was noted every 10 minutes using an instantaneous scan sampling method. The tree composition data was gathered from previously created tree plots, made by the Fauna Forever staff. I found that the home range sizes of the four study groups varied between 2.6 ha and 17.9 ha. The data from the tree plots showed no statistically significant difference in where the tamarins chose to live. There was also no statistically significant difference between the four study groups in behaviour, except for how high up in the trees they groups spent their time. There was a lack of good data in this study, due to time- and material constraints, but overall the home ranges were of close to similar size as earlier studies, and the behaviour of the tamarins was in general also consistent with earlier studies. More research would be needed to answer the further questions that arose during this study concerning the ecological constraints of the tamarins home range.
9

The Saguwentje of Berg En Dal

Veres, Michael J. 27 November 2012 (has links)
No description available.
10

O mico-leão-dourado ( Leontopithecus rosalia) como dispersor de sementes na Reserva Biológica União/IBAMA, Rio das Ostras, RJ. / "The golden lion tamarin (Leontopithecus rosalia) as a seed dispersal in the Uniao Biological Reserve, Rio das Ostras, RJ"

Lapenta, Marina Janzantti 29 May 2002 (has links)
O papel do mico-leão-dourado ( Leontopithecus rosalia) como dispersor de sementes na Reserva Biológica União foi avaliado pelo acompanhamento mensal de dois grupos de micos, de dezembro de 1998 a dezembro de 2000, num total de 871,9h de observações no campo. No período de estudo os micos se alimentaram dos frutos de 57 espécies de árvores de pelo menos 17 famílias, ingerindo sementes de 39 espécies,das quais 23 foram colocadas para germinar em laboratório e/ou no campo. Leontopithecus rosalia pode ser considerado como agente dispersor legítimo para as espécies estadas, porque as sementes de todas as espécies germinaram, mesmo que em baixas porcentagens, após a ingestão. Também foi avaliada a velocidade de germinação das sementes. Estes primatas não apresentam um efeito consistente na germinação final de sementes, pois beneficiam algumas espécies, enquanto prejudicam a porcentagem e/ou velocidade da germinação de outras. Para as espécies de frutos mais consumidas foram anotados o tamanho e formato das sementes engolidas, o número de árvores visitadas, além dos hábitats de ocorrência das árvores e dos locais onde as fezes foram depositadas. O tempo de retenção das sementes no trato digestório e a distância de dispersão foram medidos, bem como foram procuradas sementes predadas e digeridas nas fezes. O tempo médio de passagem para as sementes das espécies ingeridas foi de 1,1 + 0,3h e a distância média de dispersão de 107,8 + 70,6m, sendo que de modo geral as sementes dispersadas por mamíferos não são depositadas próximo às árvores parentais. O hábitat de deposição das fezes foi adequado para a germinação das sementes para 88,9% das espécies testadas, estando de acordo com o ambiente das árvores visitadas pelos micos-leões. O mico-leãodourado é um dos primatas mais ameaçados de extinção do mundo, e estudos sobre seu comportamento e ecologia irão contribuir para a preservação da espécie, de seu hábitat, e da Reserva Biológica União, uma das últimas áreas de Mata Atlântica de Baixada Costeira do Estado do Rio de Janeiro. / The role of the golden lion tamarins (Leontopithecus rosalia) as a seed disperser was studied in União Biological Reserve. Two groups of golden lion tamarins were studied during 24 months from December 1988 to December 2000, on a total of 871.9h. During the study period the tamarins fed on fruits of 57 species of trees at least from 17 families. Seeds from 39 species were ingested, and of them, 23 were put to germinate in lab and/or in the field. Leontopithecus rosalia can be considered as a legitimate seed disperser for the tested species, because seeds of all species germinated after ingestion, even in low ercentages. It was still considered the seed germination velocity. These primates do not have a consistent effect on seed germination, since benefit the germination percentage and/or velocity of some species and decrease of others. It was noted the size and shape of swallowed seeds from most frequently eaten species, the total number of visited trees, the habitat where these trees occur and where the faeces were deposited. The retention time of the seeds in the gut and the dispersion distance was noted, and damage and digested seeds were searched in the faeces. The mean time of gut passage from seeds of ingested species was 1.1+0.3h and the mean distance of dispersion was 107.8 + 70.6m, and the seeds dispersed by mammals were not usually defecated near the parental trees. The habitats of faecal deposition and of visited trees were the same in 88.9% of tested species, being possibly appropriated for seed germination and establishment. The golden-liontamarin is one of the most threatened primates in the world, and studies on their behaviour and ecology will contribute to preserve the species the habitat, and the União Biological Reserve, one of the last areas of lowland Atlantic Forest of southeast Brazil.

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