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Ecologia populacional do bagre cego de Iporanga, Pimelodella kronei (Siluriformes: Heptateridae), do Vale do Alto Ribeira, Iporanga - SP: uma comparação com Trajano, 1987 / Population ecology of blind catfish from Iporanga, Pimelodella kronei (Siluriformes, Heptapteridae) in the Upper Ribeira Valley, Iporanga-SP: a comparison with Trajano, 1987Ana Luiza Feigol Guil 20 September 2011 (has links)
O bagre cego de Iporanga, Pimelodella kronei, da região do Parque Estadual Turístico do Alto Ribeira-PETAR, SP, foi o primeiro peixe troglóbio descoberto e descrito no Brasil e um dos mais estudados até hoje. Populações de bagres cegos atribuídas a essa espécie foram encontradas, até o momento, em cavernas do Sistema das Areias (Areias de Cima - localidade-tipo e abrigando a maior população conhecida -, Areias de Baixo e Ressurgência das Areias da Água Quente, esta aparentemente com uma população periférica), na Caverna Córrego Seco, na Ressurgência de Bombas e em cavernas do Sistema Alambari (caverna Alambari de Cima - população aparentemente extinta -, e Abismo do Gurutuva). Os bagres cegos do Sistema Areias foram excessivamente coletados na década de 1970, o que teria provocado um declínio populacional acentuado, registrado por Trajano (1987) 10 anos mais tarde. O presente estudo aborda a ecologia de P. kronei, com ênfase na população das Areias, utilizando métodos comparáveis aos de Trajano (op. cit.), para fins de monitoramento. Os aspectos analisados nas Areias foram: tamanho da população, crescimento individual e deslocamentos no habitat, a partir de marcação e recaptura individual; estrutura da população em termos de distribuição das freqüências de tamanhos (comprimento-padrão), peso e fator de condição (isométrico e alométrico); troglomorfismos (graus de redução de olhos e de pigmentação melânica). Complementarmente, exemplares das Areias, Bombas, Córrego Seco e Gurutuva foram comparados quanto à morfometria. A população de P. kronei das Areias mostrou evidências de estabilidade através da recuperação da estrutura de peso e comprimento-padrão. Assim como observado para outras espécies de siluriformes troglóbios, o crescimento individual é altamente heterogêneo, com casos de crescimento negativo. Os parâmetros da equação de Von Bertallanfy revelaram valores superiores aos de Trajano (1987), resultando em uma longevidade média de 15-20 anos. Os bagres estudados na Areias de Cima mostraram tendência de deslocamentos rio acima, em direção ao ponto mais distal no Córrego Grande (mais próximo à entrada de alimento externo), provavelmente para alimentação e reprodução. É possível que existam diferenças entre a população de Bombas e as demais localidades, sendo necessária uma investigação mais aprofundada, com métodos mais discriminatórios. / The blind catfish from Iporanga, Pimelodella kronei, from Parque Estadual Turístico do Alto Ribeira- PETAR, SP, was the first troglobitic fish discovered and described in Brazil. It is also one of the most investigated species so far. Populations of blind catfish attributed to this species have been found in caves belonging to the Areias System (Areias de Cima - type-locality, sheltering the largest known population - , Areias de Baixo and Ressurgence of Areias of Águas Quente, which apparently shows a peripherical population), besides Córrego Seco Cave, Bombas Ressurgence and caves of the Alambari System (Alambari de Cima - an apparently extinct population - , and Gurutuva). The blind catfish of Areias system were over-collected during the 1970s, which may have led to an accentuated population decline, as recorded by Trajano (1987) ten years later. The present study focus on the ecology of P. kronei, with emphasis on the Areias population, by using methods comparable to those by Trajano (op. cit.) for monitoring purposes. The aspects studied in the Areias caves were: population size, individual growth and movements in the habitat, based on individual marking and recapture; population structure in terms of distribution of size (standard length), weight and condition factor (isometric and alometric) frequencies; troglomorphism (levels of eye reduction and melanic pigmentation). In addition, samples from Areias, Bombas, Córrego Seco and Gurutuva were morphometrically compared. The P. kronei population of Areias showed evidence of stability through the regain of the size and weight structure. Like the observed for other troglobitic siluriforms, the individual growth in P. kronei is highly heterogeneous, with frequent cases of negative growth. The parameters of the Von Bertallanfy equation calculated were higher than those by Trajano (1987), resulting in a higher expected longevity - 15 to 20 years. The blind catfish from Areias presented a tendency to move upstream, approaching the distal end of Córrego Grande (closer to the input of epigean nutrients), probably for feeding and reproduction. There may be some differences in the Bombas populations of other locations, to be investigated using more discriminatory methods.
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Aspectos da ecologia populacional de Gracilinanus microtarsus (Mammalia: Didelphidae) / Aspects of the population ecology of Gracilinanus microtarsus (Mammalia: Didelphidae)Almeida, Marcos Vinicius de, 1988- 25 August 2018 (has links)
Orientadores: Sérgio Furtado dos Reis, Eduardo Guimarães Martins / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-25T08:14:09Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014 / Resumo: O objetivo do presente trabalho foi investigar diversos parâmetros de interesse para a ecologia populacional de Gracilinanus microtarsus. Em particular os objetivos foram estimar probabilidade sobrevivência e verificar como a população de G. microtarsus do Cerrado de Mogi Guaçu no estado de São Paulo se comporta com relação ao contínuo de estratégias reprodutivas; estimar taxas de captura e recaptura e verificar se os indivíduos na população do Cerrado de Mogi Guaçu se comportam com relação a chance de ser mais ou menos capturados; estimar o tamanho populacional e verificar se existe variação temporal nesse parâmetro. As estimativas de sobrevivência obtidas para G. microtarsus nesse estudo no Cerrado da Fazenda Campininha no município de Mogi Guaçu em São Paulo variaram entre um mínimo de 0,484 e um máximo de 0,815. A população de G. microtarsus no Cerrado da Fazenda Campininha se comporta do ponto de vista demográfico como semalpara parcial. O tamanho populacional de G. microtarsus na área de cerrado da Fazenda Campininha mostrou-se mais elevado estatisticamente nos meses de maior pluviosidade. As estimativas nesses meses, novembro, dezembro (2005), janeiro e março (2006), variaram de 20 a 30. As estimativas nos meses de dezembro (2005) e janeiro (2006) foram as mais altas com 24 e 31, respectivamente. Nossos dados para o maior tamanho populacional estimado para os meses mais quentes descritos no trabalho, sugerem uma forte influência da estação quente e úmida, onde a oferta de alimentos, principalmente insetos, é maior na região de estudo e é aquela que parece melhor favorecer a reprodução e o desenvolvimento de filhotes da cuíca G. microtarsus / Abstract: The purpose of this study was to investigate aspects of the population ecology of Gracilinanus microtarsus. Specifically, the primary objectives were to estimate the probability of survival and to assess the behavior of the population of G. microtarsus from the Cerrado de Mogi Guaçu in the state of São Paulo with respect the semelparity-iteroparity continuum; to estimate probabilities of capture and recapture; and to estimate population size and temporal variation in this parameter. Estimates of survival varied between 0.484 and 0.815. The population of G. microtarsus in the Cerrado de Mogi Guaçu behaves as partial semelparous. Population size was higher in the months of higher pluviosity / Mestrado / Biodiversidade Animal / Mestre em Biologia Animal
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Estimating vital rates with imperfect detection in amphibian and reptile populations = Estimando taxas vitais com detecção imperfeita em populações de anfíbios e répteis / Estimando taxas vitais com detecção imperfeita em populações de anfíbios e répteisRodrigues, Murilo Guimarães, 1978- 23 August 2018 (has links)
Orientador: Ricardo Jannini Sawaya / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-23T04:29:37Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: A ecologia de populações investiga os fatores que levam a variação das taxas vitais e, consequentemente, no número de indivíduos. Isso inclui testar hipóteses sobre aspectos da história de vida das espécies e entender os fatores que podem modular a dinâmica populacional. No entanto, a obtenção de dados para testar hipóteses pode ser difícil para populações que apresentam probabilidades de detecção < 1, como anfíbios e répteis. A marcação e recaptura é amplamente usada para estimar a detecção e inferir aspectos de dinâmica populacional e testar hipóteses ecológicas. Neste trabalho empregamos a teoria de marcação e recaptura para testar hipóteses relacionadas à ecologia e conservação de populações de anfíbios e répteis. Utilizamos o programa MARK para implementar modelos de populações abertas e fechadas incorporando a probabilidade de detecção dos indivíduos, para obter estimativas de sobrevivência, e outros parâmetros populacionais usando máxima verossimilhança. Organizamos esta tese em quatro capítulos. Iniciamos enfatizando a importância da probabilidade de detecção, além de simular cenários hipotéticos para demonstrar a relação entre esforço de campo, tamanho ótimo amostral e viés amostral. Em seguida comparamos o efeito de duas técnicas de marcação, o corte de artelhos e o implante de microchips, sobre a sobrevivência individual do sapo ferreiro, Hypsiboas faber. No terceiro capítulo estimamos a sobrevivência e o crescimento populacional da jararaca-ilhoa, Bothrops insularis incorporando emigração temporária aos modelos. Além do estudo de taxas vitais e de dinâmica nas populações, a alocação de energia e suas consequências na sobrevivência individual podem ser testadas com modelos de marcação e recaptura. Assim, no quarto e último capítulo consideramos dois caracteres sexuais presentes no sistema de acasalamento dos lagartos, o tamanho da mandíbula e a coloração chamativa, para comparar as estimativas de sobrevivência entre machos e fêmeas do lagarto cauda de chicote, Cnemidophorus cf. ocellifer. . De forma geral, observamos que a probabilidade de detecção individual nos sistemas estudados foi baixa e condizente com a detecção de vertebrados em ambientes tropicais. Além disso, a inclusão de covariáveis na investigação de parâmetros vitais e no processo de detecção é fundamental para o melhor entendimento dos fatores que explicam a dinâmica de uma população. Especificamente observamos que: (i) demonstramos que as taxas que não incorporam a detecção são enviesadas em relação às estimativas que consideram a detecção, (ii) as estimativas de sobrevivência foram similares em indivíduos de Hypsiboas faber marcados com ablação de artelhos e microchips , (iii) Bothrops insularis apresentou baixa probabilidade de sobrevivência anual e crescimento populacional anual negativo. Por fim, (iv) machos maiores do lagarto Cnemidophorus cf. ocellifer apresentaram sobrevivência mensal menor do que machos menores, mas o oposto foi observado para as fêmeas / Abstract: Population ecology aims to search for factors that lead to variation in vital rates and consequently, in the number of individuals. This includes testing hypotheses about natural history traits and threats to populations. However, obtaining data to test hypotheses is challenging because following individuals in the field can be difficult, especially for amphibians and reptiles, where detection probabilities are often < 1. Mark-recapture methods are widely used to estimate detection probabilities and to test ecological hypothesis. Here we used mark-recapture methods to test hypotheses related to ecology and conservation of amphibian and reptile populations. We implemented open- and closed-population models in Program MARK, to account for detection probabilities and to calculate survival estimates and other population parameters. We organized this dissertation into four chapters. In the first chapter we emphasize the importance of considering detection probabilities besides simulating hypothetical scenarios to show the relationship between field effort, sample size and precision. In the second chapter we used a Cormack-Jolly-Seber model to compare the effect of two amphibian marking techniques, toeclipping and PIT tagging, on survival in the blacksmith tree frog, Hypsiboas faber. In the third chapter our goal was to estimate survival and population growth of the golden lancehead, Bothrops insularis accounting for temporary emigration using Pollock's Robust Design. Besides the study of vital rates and population dynamics, energy allocation and its consequences for survival are testable with mark-recapture models. Thus, in the last chapter we used two traits from the lizard mating system, namely jaw size and courtship coloration, to compare survival estimates between males and females of the whiptail lizard, Cnemidophorus cf. ocellifer. In summary we observed that detection probability on the studied populations were low and similar to other vertebrate populations from the tropics. However, including covariates in estimation models of vital rates and detection is important to obtain more accurate results to explain population dynamics. Specifically we conclude that (i) return rates were biased low in relation to survival estimates that account for detectability, (ii) the estimates of survival were similar between toe-clipped and PIT tagged individuals of Hypsiboas faber, (iii) Bothrops insularis showed low survival probability and negative annual population growth. And (iv) larger Cnemidophorus cf. ocellifer males showed lower monthly survival probability than smaller males but the opposite was found for females / Doutorado / Ecologia / Doutor em Ecologia
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Zonation pattern and spatial arrangement of a Geukensia granosissima population in a mixed mangrove forest of Tampa BayHudson, Derrick Shane 22 March 2017 (has links)
Here I provide the first report on Geukensia granosissima patterns of abundance along a tidal gradient within a mixed mangrove stand located in Tampa Bay, Florida, USA. Specifically, I examined 1) the relationship between G. granosissima size and density with mangrove root type (e.g. prop root, pneumatophore), and of density within the intertidal zones; and 2) the possible role of predation in shaping the lower zonation patterns displayed. Transect surveys located along the lower and upper population limit boundaries were conducted every two months over a ten-month period. Variables measured include size distribution, density of mussels, above ground mangrove prop and pneumatophore roots. To evaluate potential predator influence on mussel distribution, predator exclusion experiments were conducted in March and June 2016, using mock pneumatophore platforms at both high and low tidal elevations. Surveys indicated that over all dates mean mussel densities and percent cover were higher along the lower limit tidal elevation [mean (± SD) = 1280.3 ± 665.9 m-2 and 20.6 ± 3.78% respectively], versus that in the higher limit tidal elevation [102.4 ± 50.7 m-2 and 0.52 ± 0.17%]. Survivorship of mussels in the predator exclusion platforms placed at higher position within lower edge of the mussel tidal distribution was approximately 100% on both experimental dates. During March 2016, mussel survivorship was lower when predators had access to mussels with the greatest loss of mussels in the lower (26% survivorship) vs. higher (66.5%) tidal elevations after 48h. Similarly, when predators had access to mussels in June experiments, after just 24 h mussel loss was greater at lower (1% survivorship) vs. higher (80% survivorship) tidal elevations, possibly reflecting differences in predator densities, identities, and/or functional responses. Overall trends in the patterns of distribution of this population of G. granosissima suggest that the lower tidal boundary of the mussel is shaped by predation but that predation plays a lesser role in the high tidal areas.
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AN ASSESSMENT OF STREAM QUALITY IN RELATION TO POPULATION HEALTH OF PLANTAGO CORDATAHudgens, Faith Victoria 01 September 2021 (has links)
Understanding the health of rare and at-risk plant species is crucial for the conservation of biodiversity. Rare and at-risk species are often specialists with very specific requirements for growth and reproductive success. Some parameters associated with growth and reproductive success of rare aquatic species may include biotic and abiotic factors such as herbivory, competition, water depth, pH, and other factors associated with habitat quality. In this thesis, the population health of the rare and at-risk aquatic species Plantago cordata in Southern Illinois streams is assessed in relation to stream quality of sites containing Plantago cordata and sites without Plantago cordata.The objectives of this study were to (1) Determine if there is a relationship between population size structure and biotic habitat factors among populations and sites, and (2) Determine if there is a relationship between population size structure and abiotic habitat factors among populations and sites. Hypotheses were constructed using the hierarchy-of hypotheses method and most narrow alternative hypotheses are as follows: (1) There will be significant relationships between biotic and abiotic factors and Plantago cordata growth and reproductive success. (2) Levels of herbivory will have significant relationships with growth and reproductive success of Plantago cordata. (3) The abundance of co-occurring species individually and considered in functional groups (graminoid, herb, woody) will have significant relationships with growth and reproductive success of Plantago cordata. (4) Stream depth will have a unimodal relationship with growth and reproductive success of Plantago cordata, with maximum performance at an intermediate stream depth. (5) Stream pH will have a unimodal relationship with growth and reproductive success of Plantago cordata. (6) Stream quality (as outlined by the QHEI assessment) will have significant relationships with growth and reproductive success of Plantago cordata. General trends in herbivory suggest that Plantago cordata could be at greatest risk of herbivory during warmest average temperatures of the study season. There is evidence to suggest that flowering individuals could have a greater threat of herbivory than other growth stages based on Kendal correlation results. A Wilcox test determined that there were no statistical differences in species richness for plots with versus without Plantago cordata. There were relatively low values for percent cover of co-occurring species when considered in functional groups and there was overall relatively low species richness across all communities. Despite this, non-metric multidimensional scaling (NMDS) of community data provided evidence to suggest that there were statistical differences in the species composition of co-occurring individual riparian species among P. cordata populations. A significant negative correlation for water depth and flowering individuals and a significant positive correlation with water depth and pH occurred. A significant positive correlation for stream pH with the numbers of seedlings and dehiscing individuals was also found. One-way analyses of variance (ANOVAs) showed that some populations containing Plantago cordata were found to have stream pH values statistically different from nearby IEPA control streams without Plantago cordata. One population of Plantago cordata was found to be significantly different than two other populations in regards to stream pH using a linear mixed model. A principal components analysis (PCA) of stream Qualitative Habitat Evaluation Index (QHEI) assessments demonstrated distinct clustering of Plantago cordata streams and control IEPA streams without Plantago cordata. These findings provide partial evidence to suggest that growth and reproductive success of Plantago cordata could potentially be impacted by the abiotic and biotic parameters explored in this thesis.
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Measuring Avian Breeding Diversity and Nesting Activity in Fragmented Pine PlantationsWare, Kathryn 24 May 2022 (has links)
No description available.
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Michael Rohde Thesis.pdfMichael L Rohde (15354475) 27 April 2023 (has links)
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<p>Many species of turtle are facing serious declines from multiple anthropogenic causes. One such turtle native to the United States, the Blanding’s Turtle (<em>Emydoidea blandingii</em>), has faced declines in nearly every sector of their range, yet few populations have known recorded demographics, such as abundance, density, sex ratio, and body sizes. To inform managers of these crucial demographic measures of three spatially adjacent populations on Camp Grayling, MI, I implemented a capture-mark-recapture study from 2021 to 2022. I calculated Lincoln-Petersen Index and ran constant, time-varying, and behavioral response models for both full and conditional likelihoods in Program MARK. All best fit models estimated populations ≥30. The three populations sampled at Camp Grayling were low in abundance, densities, and biomass compared to some more well-known populations. Adult body weight means were 1456 g and 1223 g for males and females, respectively. Mean carapace lengths for males was 22.42 cm and females were 20.11 cm. The males of these populations were significantly larger than the mean found across the Blanding’ Turtles range. There is evidence of recruitment within these populations. A long-term research plan should be implemented and focus on investigating connectedness of these populations, as well as building data for population viability analyses. Additionally, immediate conservation action should take place to protect this vulnerable species.</p>
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Dormant Propagules in Demographic Studies: a Recurrent Bias and Potential SolutionsBorghesi, Federico 01 January 2023 (has links) (PDF)
In the face of unprecedented anthropogenic change, we increasingly turn to emergent technologies and extensive data sets for solutions that complement much needed systemic changes in our societies. These technological solutions, however, must be approached with care. We must recognize and address biases in the way data has been accumulated. In demographic studies, dormant life stages, such as seed banks, and other cryptic factors have often been neglected. The potential consequences of these omissions have been extensively described in the literature. In the first chapter, I analyze patterns of seed bank omissions in demographic models, finding unjustified omissions are widespread across ecoregions, growth forms, and taxonomic groups. More importantly, studies with longer duration and accounting for a greater range of conditions were less likely to neglect the seed bank. Unfortunately, most demographic studies are conducted for relatively short periods and are limited to one or a few sites. In addition, modeling tools often focus on mean behavior and do not properly characterize variability. In the second chapter, I explore the use of Bayesian generalized linear mixed models to characterize vital rates and compare their variation across growing conditions. Using wild and translocated populations of Dicerandra christmanii,this study tests the ability of this approach to evaluate early translocation success and site suitability.In chapter 3, I expand the demographic analysis of Dicerandra christmaniiand provide an example of the use of Bayesian-fitted Integral Projection Models (IPMs) to combine data sources and incorporate seed dynamics into demographic models. By propagating uncertainty from vital rates to derived population metrics, this study illustrates the consequences of accounting for the seed bank stage and site condition to our assessment of population viability. In the final part of this work, I present potential routes to expand field and modeling tools to help address the inclusion of dormant and cryptic life stages into demographic studies. Among these, I recommend exploring more complex sampling schemes, informed priors, and expanded IPMs.
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The Effects of Bot Fly (<i>Cuterebra Fontinella</i>) Parasitism on the Ecology and Behavior of the White-Footed Mouse (<i>Peromyscus Leucopus</i>)Cramer, Michael John 03 April 2006 (has links)
No description available.
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Effects of Host Density, Active Burrow Density, and Sex Ratio on Ectoparasite Load of Black-tailed Prairie Dogs (<i>Cynomys ludovicianus</i>) in Northern ColoradoSearl, Kari F. 30 July 2010 (has links)
No description available.
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