In south Florida, the Greater Everglades ecosystem supports sixteen species of wading birds. Wading birds serve as important indicator species because they are highly mobile, demonstrate flexible habitat selection, and respond quickly to changes in habitat quality. Models that establish habitat relationships from distribution patterns of wading birds can be used to predict changes in habitat quality that may result from restoration and climate change. I developed spatio-temporal species distribution models for the Great Egret, White Ibis, and Wood Stork over a decadal gradient of environmental conditions to identify factors that link habitat availability to habitat use (i.e., habitat selection), habitat use to species abundance, and species abundance (over multiple scales) to nesting effort and success. Hydrological variables (depth, recession rate, days since drydown, reversal, and hydroperiod) over multiple temporal scales and with existing links to wading bird responses were used as proxies for landscape processes that influence prey availability (i.e., resources). In temporal foraging conditions (TFC) models, species demonstrated conditional preferences for resources based on resource levels at differing temporal scales. Wading bird abundance was highest when prey production from optimal periods of wetland inundation was concentrated in shallow depths. Similar responses were observed in spatial foraging conditions (SFC) models predicting spatial occurrence over time, accounting for spatial autocorrelation. The TFC index represents conditions within suitable depths that change daily and reflects patch quality, whereas the SFC index spatially represents suitability of all cells and reflects daily landscape patch abundance. I linked these indices to responses at the nest initiation and nest provisioning breeding phases from 1993-2013. The timing of increases and overall magnitude of resource pulses predicted by the TFC in March and April were strongly linked to breeding responses by all species. Great Egret nesting effort and success were higher with increases in conspecific attraction (i.e., clustering). Wood Stork nesting effort was closely related to timing of concurrently high levels of patch quality (regional scale) and abundance (400-m scale), indicating the importance of a multi-scaled approach. The models helped identify positive and negative changes to multi-annual resource pulses from hydrological restoration and climate change scenarios, respectively. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection

Thesis (MTech (Environmental Health))--Cape Peninsula University of Technology, 2019. / Background: A recent review on the effects of ambient air pollution on human health in sub-Saharan Africa, specifically calls for an urgent need for more epidemiological studies in developing countries due to a lack of data in these countries. Air pollution information on exposure is important for understanding and addressing its public health impact in developing countries. In many African countries, the spatial distribution of air pollutants has not been quantified even though air pollution is a global public health risk. The main goal of the study was to quantify and compare the seasonal spatial variation of household air pollution in the 4 Western Cape neighbourhoods. Methods: Weekly indoor and outdoor measurements of Particulate Matter (PM2.5), Sulphur dioxide (SO2), Ozone (O3), Carbon monoxide (CO) and Nitrogen dioxide (NO2) were conducted at 127 households in four informal settlement areas (Khayelitsha, Marconi-Beam, Masiphumulele and Oudtshoorn) during one month each in summer and winter. PM2.5 measurements were conducted using Mesa Labs GK2.05 (KTL) cyclone with the GilAir Plus Air Sampling Pump, Gases were measured using Passam passive samplers. Statistical analyses were performed using Stata V12. Simple linear regression was used to evaluate the relationship between continuous exposure levels and the respective predictor variables. These include distance to major roads, bus routes, open grills and waste burning sites. Results: The highest average weekly outdoor PM2.5 and NO2 concentrations for summer were recorded in Milnerton (8.76 µg/m3 and 16.32 µg/m3 respectively). However, the highest average concentrations during winter for PM2.5 were recorded in Oudtshoorn (PM2.5: 16.07 µg/m3), whilst the highest NO2, was recorded in Khayelitsha (NO2: 35.69 µg/m3). SO2 levels were consistently low during both seasons. Noordhoek generally recorded the lowest average levels for all pollutants. Winter average weekly concentrations were generally higher than the levels recorded in summer for all pollutants. In a sub-sample of indoor and outdoor measurements, the results were comparable for PM2.5, NO2 and CO. However, the results of Ozone (O3) showed relatively higher (~10 times) outdoor compared to indoor levels. Linear regression modelling results revealed that significant predictors of elevated exposure to PM2.5 were proximity to construction activities and open grills. Analysis demonstrated a clear dose-response relationship with distance, with open grills within 1000m associated with a 0.33 µg/m3 increase in PM2.5 to 6.77 µg/m3 at a distance of 25 meters. Results from the linear regression modelling revealed that significant predictors of exposure to NO2 were proximity to rapid transport bus stops, bus routes, taxi routes and major routes. Distance to rapid transport bus stops demonstrated an increase in NO2 between 0.09 µg/m3 (at 1km) to 2.16 µg/m3 (at 50m) during summer. A similar pattern was observed for taxi routes and bus routes displaying an increase of 6.26 μg/m3and 6.82 μg/m3 respectively within the proximity of 1000 meters. / MAUERBERGER Foundation Scholarship

A utilização de sistemas de bateria de gaiolas é assunto de grande polêmica nos países da Europa, sendo que a maior preocupação com o uso de gaiolas se dá quanto ao espaço oferecido às aves poedeiras, o qual certamente afeta seu bem-estar. Sendo assim este trabalho teve como objetivos avaliar os aspectos relacionados ao comportamento e bem-estar das aves, comparando o sistema de criação convencional (bateria de gaiolas) com um sistema de criação em cama, ninho e poleiro, bem como avaliar a influencia das condições ambientais (estresse e conforto) na qualidade final dos ovos, associando técnicas da zootecnia de precisão (análise de imagens), para avaliar as respostas comportamentais das diferentes linhagens nas diferentes condições. Dois grupos de 20 aves (10 Hy-line W36 e 10 Hy-line Brown) em inicio de postura foram submetidas a duas condições ambientais durante duas semanas consecutivas (26°C e 60% UR e 35°C e 70%UR), sendo também submetidas a dois sistemas de criação (bateria de gaiolas e cama). Durante o período de avaliação um sistema de câmeras de vídeo registrava o comportamento das aves. Os ovos produzidos durante todo o período da pesquisa foram avaliados pela análise dos seguintes parâmetros de qualidade: peso do ovo, espessura da casca, gravidade especifica, unidades Haugh, além de análise da colorimetria da gema, porosidade da casca e análises microbiológicas, para a verificação de uma possível ocorrência de contaminação por Salmonella sp na gema e casca dos ovos. Os resultados obtidos revelaram uma redução significativa (P<0,05) nos parâmetros de qualidade do ovo para a condição de estresse térmico, principalmente para o sistema de criação em gaiolas. Quanto as análises de comportamento, o sistema de criação em cama proporcionou a expressão de todos os comportamentos naturais e de conforto das aves, favorecendo assim melhores condições de bem-estar. Para o sistema de criação convencional (gaiolas) foi possível verificar que mesmo sem nenhuma condição, as aves ainda tentavam executar seus comportamentos naturais, sendo que a impossibilidade de expressarem estes comportamentos certamente agravou a condição de estresse provocada por este sistema de criação. Pela análise dos dois sistemas de criação e das duas condições ambientais a linhagem Hy-Line W36. foi a que obteve um melhor desempenho. / The battery cage system is a very polemic issue in European countries, being the most commonly raised concerns focused on the spatial restrictions of the hens, which might compromise important comfort movements affecting their welfare conditions. This work aimed to evaluate aspects related to behavior and welfare of hens comparing a conventional housing system (laying cages in battery) with another system using litter, lair and roost. In addition, the effects of environmental conditions (stress or comfort) on final egg quality and behavior responses (analyzed by precision techniques) were evaluated in different laying hen lines. Two groups of 20 birds (10 Hyline W36 and 10 Hy-line Brown) at the beginning of production phase were submitted to two environmental conditions (26°C with 60% RU or 35°C with 70% RU) and two housing systems (cages in battery or litter) during two consecutive weeks. During the evaluation period, bird behaviors were recorded by video cameras. Total egg production was analyzed according to egg weight, shell thickness, specific gravidity, Haugh unit, yolk colorimetric parameters and shell porosity. Eggs were microbiologically analyzed in order to detect Salmonella sp contamination in yolk and eggshell. A significant (P<0.05) reduction in quality parameters was observed in eggs from laying hens raised under heat stress, mainly in those from laying cage system. In relation to behavior, the housing system in litters proportioned the expression of all natural behaviors and those related to bird comfort, which permitted to improve welfare conditions. In conventional system (laying cages) was verified that birds tried to manifest their natural behavior in spite of lacking condition for it. This impossibility for executing natural behaviors promoted an increase of stress provoked by the housing system. Analyzing both systems and environmental conditions, hens from Hy-Line W36 showed the better performances.

A utilização de sistemas de bateria de gaiolas é assunto de grande polêmica nos países da Europa, sendo que a maior preocupação com o uso de gaiolas se dá quanto ao espaço oferecido às aves poedeiras, o qual certamente afeta seu bem-estar. Sendo assim este trabalho teve como objetivos avaliar os aspectos relacionados ao comportamento e bem-estar das aves, comparando o sistema de criação convencional (bateria de gaiolas) com um sistema de criação em cama, ninho e poleiro, bem como avaliar a influencia das condições ambientais (estresse e conforto) na qualidade final dos ovos, associando técnicas da zootecnia de precisão (análise de imagens), para avaliar as respostas comportamentais das diferentes linhagens nas diferentes condições. Dois grupos de 20 aves (10 Hy-line W36 e 10 Hy-line Brown) em inicio de postura foram submetidas a duas condições ambientais durante duas semanas consecutivas (26°C e 60% UR e 35°C e 70%UR), sendo também submetidas a dois sistemas de criação (bateria de gaiolas e cama). Durante o período de avaliação um sistema de câmeras de vídeo registrava o comportamento das aves. Os ovos produzidos durante todo o período da pesquisa foram avaliados pela análise dos seguintes parâmetros de qualidade: peso do ovo, espessura da casca, gravidade especifica, unidades Haugh, além de análise da colorimetria da gema, porosidade da casca e análises microbiológicas, para a verificação de uma possível ocorrência de contaminação por Salmonella sp na gema e casca dos ovos. Os resultados obtidos revelaram uma redução significativa (P<0,05) nos parâmetros de qualidade do ovo para a condição de estresse térmico, principalmente para o sistema de criação em gaiolas. Quanto as análises de comportamento, o sistema de criação em cama proporcionou a expressão de todos os comportamentos naturais e de conforto das aves, favorecendo assim melhores condições de bem-estar. Para o sistema de criação convencional (gaiolas) foi possível verificar que mesmo sem nenhuma condição, as aves ainda tentavam executar seus comportamentos naturais, sendo que a impossibilidade de expressarem estes comportamentos certamente agravou a condição de estresse provocada por este sistema de criação. Pela análise dos dois sistemas de criação e das duas condições ambientais a linhagem Hy-Line W36. foi a que obteve um melhor desempenho. / The battery cage system is a very polemic issue in European countries, being the most commonly raised concerns focused on the spatial restrictions of the hens, which might compromise important comfort movements affecting their welfare conditions. This work aimed to evaluate aspects related to behavior and welfare of hens comparing a conventional housing system (laying cages in battery) with another system using litter, lair and roost. In addition, the effects of environmental conditions (stress or comfort) on final egg quality and behavior responses (analyzed by precision techniques) were evaluated in different laying hen lines. Two groups of 20 birds (10 Hyline W36 and 10 Hy-line Brown) at the beginning of production phase were submitted to two environmental conditions (26°C with 60% RU or 35°C with 70% RU) and two housing systems (cages in battery or litter) during two consecutive weeks. During the evaluation period, bird behaviors were recorded by video cameras. Total egg production was analyzed according to egg weight, shell thickness, specific gravidity, Haugh unit, yolk colorimetric parameters and shell porosity. Eggs were microbiologically analyzed in order to detect Salmonella sp contamination in yolk and eggshell. A significant (P<0.05) reduction in quality parameters was observed in eggs from laying hens raised under heat stress, mainly in those from laying cage system. In relation to behavior, the housing system in litters proportioned the expression of all natural behaviors and those related to bird comfort, which permitted to improve welfare conditions. In conventional system (laying cages) was verified that birds tried to manifest their natural behavior in spite of lacking condition for it. This impossibility for executing natural behaviors promoted an increase of stress provoked by the housing system. Analyzing both systems and environmental conditions, hens from Hy-Line W36 showed the better performances.

This thesis examined the impact of anthropogenic alterations in four riverine catchments of the Eastern Mt. Lofty Ranges, South Australia, to identify if creek restoration via environmental flows is a viable management option and if so, to determine; 1) Whether an aquatic/riparian viable seed bank was present and if so what was its composition 2) The ecological condition of selected riverine reaches. This in combination with the seed bank study would identify those creeks that would most benefit from the imposition of environmental flows 3) The response of key species to the water regimes likely to result from the imposition of environmental flows 4) The influence of nutrient enrichment under a fluctuating water level and to use this information to formulate best practice policy for environmental flows 5) Whether aquatic plants promoted by environmental flows were a significant fraction of the diet for higher trophic levels represented by Trichopterans and Amphipods. The seed banks were of comparable density (ranging from 4,000 to 110,000 seeds m-2) and species richness (ranging from 13 to 20 aquatic / riparian species) to the seed banks of other Australian rivers and wetlands, but this varied significantly among riverine sections and across catchments. Out of a total of 81 species recorded, 51 were classified as terrestrial (63% of all species recorded). What is of greater concern was the number of exotic (both aquatic and terrestrial) species recorded: 43% of the species recorded in the Angas, 47% of the species in the Finniss, 39% of the species in Tookayerta creek and 43% of the species recorded in Currency creek were exotic, which are significantly higher in comparison to other Australian studies. There were 24 to 28 aquatic/riparian species recorded in the extant vegetation of each catchment that were not recorded in their seed banks. Likewise, a number of species (3 to 7) were recorded in each catchments seed bank that were not recorded in the extant vegetation of those catchments. A species of particular interest is Crassula sieberana, which is on the State endangered plant species list. Indices for assessing the ecological condition, health or integrity of a river or riparian habitat were employed to investigate the relationship between the river/riparian habitat and the land and water management practices associated with those habitats. Of the four catchments surveyed, each catchment identified a unique set of site parameters (subindex indicators) that were strongly correlated with its ecological condition. Indicator species analyses revealed pasture grasses to be a significant indicator of reaches in very poor condition (p = 0.0010) along the Finniss and Baumea juncea of those reaches in good condition (p = 0.0230). Along the Angas, Cotula coronopifolia was an indicator of those reaches in average condition (p = 0.0240) and along Currency creek, Cladium procerum was an indicator of those reaches in good condition (p = 0.0190). However, when all 115 surveyed reaches were analysed together, those reaches of average to excellent ecological condition were all strongly correlated (R2 = 0.50) with the subindex indicators: bank stability, % riparian cover, grazing, fenced, aquatic wood, and width of the riparian vegetation. This would indicate that these subindex indicators are the main site parameters determining the ecological condition of a riverine reach and hence its restoration potential. Those catchments or sub-catchments containing a high proportion of reaches classified to be in poor to very poor condition had significantly reduced seed banks. The influence of water level fluctuations (±15 cm, ±30 cm and ±45 cm) on the growth of four species of emergent macrophytes (Cyperus vaginatus, Phragmites australis, Typha domingensis and Triglochin procerum) were species dependent. These species naturally inhabits different zones across the elevation gradient. C. vaginatus, which has a high elevation preference, was strongly inhibited by increasing water depth and fluctuations in water levels. In contrast, species with an intermediate elevation preference, such as Phragmites australis and Typha domingensis, were more tolerant to both depth and water level fluctuations. However, the biomass and relative growth rate (RGR) of T. domingensis and P. australis were depressed when grown under the combination of deep elevation and a highly fluctuating water level (±45 cm). Between the static and ±45 cm amplitude treatments, growth of T. domingensis was inhibited by 52%. The growth of P. australis appeared to be enhanced by fluctuating water levels and only showed a severe drop-off in growth in the deep elevation, ±45 cm amplitude treatment. In C. vaginatus the RGR was dependent of the average emergent surface area (and the implied rate of carbon acquisition)(p<0.0001; r2=0.7196; F=87.276; n=36; RGR (mg g-1 day-1) = -5.096 + 4.313 × ln (Average emergent surface area (cm2)), but this was not the case in P. australis and T. domingensis (p>0.05) even when the photosynthetic canopy was partially inundated by rising water levels. Yet these two species demonstrated different growth rates when grown under different water regime amplitudes and at different elevations. Growth of T. procerum did not respond to either amplitude or elevation, but its RGR remained negative. This suggests that another factor(s) was limiting the growth of P. australis, T. domingensis and possibly T. procerum, a factor that varies with water level. Cyperus gymnocaulos had significantly increased plant performance (p <.0001) with increased nutrient loading rates but this effect was significantly reduced under a fluctuating water regime (p =0.0007). Remarkably, under a fluctuating regime, P. australis had a significant reduction in performance with increased nutrient loading rates (p =0.0013), whereas T. domingensis performance was significantly limited (p =0.034) even with increased nutrient loading rates. T. procerum too had increased plant performance with increased nutrient loading rates but this effect was reduced under a fluctuating regime. The morphological response by T. procerum demonstrates that it is mainly limited by the nutrient loading rates and not the water regime. However, it was significantly limited/reduced by its increased turnover rates caused by a stochastic fluctuating water regime. Illustrating that in fact the effects of nutrient enrichment on T. procerum were independent of water regime but bearing in mind that water regime is the primary factor determining the productivity of this species. For those species with higher elevation preferences, e.g. C. gymnocaulos, or low elevation preference, e.g. T. procerum, the effects of nutrient loading are independent of water regime, whereas those species with an intermediate elevation preference, e.g. P. australis and T. domingensis the effects of nutrient loading are largely dependent on the water regime. Amphipoda and Trichoptera selectively fed on succulent semi-emergent macrophytes across sites of average to excellent ecological condition (31-64% to 65-97% of diet), depending on availability. These semi-emergent macrophytes contained the lowest C:N ratio (≈10:1), closest to that of their consumers (≈5:1) and therefore the highest nutritional content. In degraded riverine reaches, there were limited food resources available, hence course particulate organic matter (CPOM) formed the main dietary components of Amphipoda (20-53% of diet) even though it had the highest C:N ratio (≈40:1). At site VP. 1, filamentous algae was the main dietary component of Trichoptera (48-64% of diet) due to its availability and its low C:N ratio (≈14:1) in comparison to the other primary sources available. The imbalanced consumer-resource nutrient ratios in these degraded riverine reaches are likely to impose constraints on the growth and reproduction of their aquatic shredder communities with probable knock-on effects at higher trophic levels. The installation of environmental flows to restore and promote aquatic/riparian plant communities, which in turn would benefit higher trophic organisms, is a viable and realistic management option along selected reaches. Those selected reaches contain a significant aquatic/riparian seed bank and with sufficient physical habitat remaining to promote their germination and establishment. However, the imposition of environmental flows as a control measure to prevent the colonisation and dominance of particular species (T. domingensis and P. australis) was deemed to be redundant as a management technique given the limited water resources available. / Thesis (Ph.D.) -- School of Earth and Environmental Sciences, 2007

Post-pelagic juvenile and subadult Kemp's ridley sea turtles (Lepidochelys kempii) (20-40 cm straight carapace length) utilize nearshore waters of the northwestern Gulf of Mexico as nursery or developmental feeding grounds. This study utilizes 10 years of entanglement netting data to characterize long-term abundance and distribution of Kemp's ridley sea turtles at index habitats in this region. Netting surveys were conducted during April-October 1993-2002, primarily at Sabine Pass, Texas and Calcasieu Pass, Louisiana. Additionally, this study takes an ecosystem-based approach to understanding factors influencing Kemp's ridley in-water abundance and distribution via the development of a conceptual model incorporating data on nesting dynamics, environmental conditions, prey availability, and predation pressure. Overall monthly mean ridley catch-per-unit-effort (CPUE) peaked in the beginning of summer (April-June), probably in response to rising water temperatures and seasonal occurrence of blue crab prey. Annual mean ridley CPUE across all study areas peaked in 1994, 1997, 1999 and 2002, suggesting a 2-3 year cycle in abundance that may be related to patterns in clutch size or hatch success at the Rancho Nuevo, Mexico nesting beach. However, ridley CPUE in nearshore waters remained relatively constant or decreased slightly even as number of hatchlings released from Rancho Nuevo increased exponentially. Annual declines in Texas strandings since 1994 and subsequent increases in Florida counterparts since 1995 suggest a shift in ridley distribution from the western to eastern Gulf in recent years. Significant declines in ridley CPUE at Sabine Pass since 1997 coincided with a concurrent reduction in blue crab size, but a similar trend was not detected at Calcasieu Pass. Kemp's ridley occurrence at study sites was not significantly related to shrimping activity/by-catch. There also were no biologically significant relationships between Kemp's ridley CPUE and abiotic factors, nor were ridleys deterred from utilizing areas frequented by bull sharks. Overall, nesting dynamics and prey availability were conceptual model components appearing to have the greatest influence on nearshore ridley occurrence.

Small peat basins (c. 10-50 m diameter) were used to obtain fine spatial resolution pollen-stratigraphic records of Holocene vegetation and land-use history in upland West Glen Affric and adjacent lowland Kintail, north-western Scottish Highlands. These data provide evidence for remarkably diverse and dynamic early to mid-Holocene vegetational mosaic and sustained later Holocene upland land-use. While acidophilous Pinus sylvestris-Betula-Calluna vulgaris communities on lower hillslopes appear comparable with other areas of the Highlands, data from floodplain and alluvial fan sediments in West Affric indicate a greater woodland diversity. Betula-dominated alluvial woods included a species-rich mix of arboreal, fen, tall-herb and ruderal herbaceous taxa, with Pinus forming small populations, confined to marginal soils. Ulmus was an important component of the lowland Betula-Alnus woods. Spatial differences in soil forming processes, particularly nutrient and base status, played a primary role in determining community composition, structure, dynamics, species diversity and stability. Inferred climatic shifts during the mid-Holocene, initially to drier, more continental conditions, followed by increased oceanicity, are suggested to have made woodland communities increasingly vulnerable to low intensity grazing disturbance and anthropogenic interference during the later Neolithic and early Bronze Age. These stresses resulted in widespread woodland decline, including that of Pinus, with the spread of blanket peat and heath on poorer hillside soils, and grassland communities on alluvial sediment. Bronze Age agricultural expansion is followed by several phases of expansion and/or intensification, with sustained pastoral and arable activity in the lowlands and on small 'islands' of richer soils in the uplands. There is little evidence for abandonment and the longevity of agricultural activity, particularly cultivation, above 250 m OD clearly indicates that the unqualified assumption of upland marginality is inappropriate. The implications for the interpretation of land-use in the Highlands from conventional palynological and archaeological records are discussed. The level of spatial and temporal detail regarding the palaeoecology of plant communities and adaptive land management evident in the present study is not afforded by conventional pollen analyses. This suggests that fine-spatial resolution palynology has the potential to contribute previously unrecognised information at scales which are directly applicable to ecological and human understanding and which can be more successfully integrated with neoecological and archaeological research, fostering closer collaboration between the disciplines.

This thesis examines a crisis of governance in the Republic of South Africa (RSA), a crisis which threatens Constitutionally guaranteed intergenerational rights to water, meaning these rights are unlikely to be upheld. RSA's post-1994 Constitution incorporated a number of historically unparalleled human rights, based on fundamental principles of human dignity and equality. This includes the right to water resources for current and future generations - making RSA one of a few countries to enshrine intergenerational rights in law. Under law, Government acts as fiduciary trustee with duties to protect the water resources for current and future generations of citizens. The thesis asserts that influences of Emmanuel Kant, John Rawls and Edith Brown Weiss are reflected in the Constitution and subsequent laws. However, historical and on-going impacts from extractive industries in the province of Gauteng are negatively impacting upon intergenerational water rights. Acid mine drainage is an acidic wastewater produced as a by-product of mineral extraction - particularly gold. It is polluting ground- and surface-waters across the province. A lack of effective government response to this issue has meant that AMD is acting as a catalyst accelerating the country's already problematic governance processes to a crisis level. As it has no long-term management plan, the government is neglecting its intergenerational responsibilities and abrogating Constitutional purpose. This situation is exacerbated by multiple, often conflicting, understandings in different sectors of society of the significance of intergenerational equity, further reinforcing the governance crisis. Due to lack of government response, non-State agents, specifically the mining and financial sectors, are becoming increasingly involved in political decision-making and governance. This has positive short-term effects in ensuring that the rights of communities that were previously affected by water shortages and pollution are upheld. Yet there are potential serious long-term repercussions for democracy in RSA as a result: non-State actors are not best equipped to determine outcomes of governance, and this may result in procedures of deliberative democracy being contravened. Robert Dahl's theories inform this thesis's understanding of deliberative democracy. Consequently, although RSA's Constitution guarantees intergenerational equity in theory, it is hard to achieve in practice. This is due to the governance crisis that has been precipitated by acid mine drainage, so that intergenerational rights to water are an unlikely long-term outcome for this developing nation.

L’étude des mécanismes endocriniens est particulièrement intéressante du fait du rôle majeur des hormones dans la régulation des interactions entre la physiologie d’un organisme, son comportement, et les modifications de son environnement. Cette thèse s’est intéressée aux relations entre le statut hormonal, les performances de reproduction et le succès reproducteur d’un oiseau marin longévif, le manchot Adélie Pygoscelis adeliae, dans un contexte environnemental soumis à des changements. Le statut endocrinien de manchots mâles a été manipulé en utilisant des implants dégradables sous-cutanés diffusant l’hormone d’intérêt ou un inhibiteur de sa sécrétion. Les effets d’une modification des niveaux d’hormones sur l’investissement parental pendant l’incubation ont été mesurés à l’aide d’observations directes et d’oeufsfactices enregistrant les paramètres d’incubation. Les niveaux de corticostérone – hormone dite de stress, de prolactine – hormone des soins parentaux, et de testostérone – hormone liée aux comportements sexuels et à l’agressivité, ont été manipulés. Les effets d’une augmentation des niveaux de corticostérone sur les performances et le succès reproducteur pendant la période de l’élevage des poussins ont également été mesurés. Enfin, les conséquences d’une légère élévation des niveaux de corticostérone pendant l’ensemble de la saison de reproduction en termes de comportement et de succès reproducteur ont été examinées. Une augmentation des niveaux de corticostérone a globalement diminué les performances et le succès de reproduction. D’autre part, une modification des niveaux de prolactine ou de testostérone a affecté la durée etles paramètres d’incubation, suggérant une implication de ces deux hormones dans le contrôle de la phénologie de la reproduction. Les résultats présentés dans cette thèse mettent l’accent sur le fait que la relation entre statut endocrinien et performances de reproduction est dose, état et contexte dépendante. Nos résultats illustrent le rôle majeur des hormones étudiées dans la régulation de l’effort reproducteur, et soulignent également l’importance de considérer les interactions entre les organismes et leur environnement. / Studying endocrine mechanisms is of particular interest because of the major role played by hormones in mediating interactions between an animal’s physiology, its behaviour, and both predictable and unpredictable regimes of environmental variation. During this PhD, I have investigated the relationships between endocrine status, reproductive performance, and reproductive output in a long-lived polar seabird, the Adélie penguin Pygoscelis adeliae, while integrating environmental parameters for some of the studies. The endocrine status of male penguins was experimentally modified using subcutaneous self-degradable pellets, which released either the hormone or an inhibitor of its secretion. The effects of changes in the levels of several hormones on the parental investment during incubation were assessed, using direct observations and dummy eggs to record incubation parameters. The levels of corticosterone – the so-called stress hormone, prolactin – the parental care hormone, and testosterone – the sexual behaviour and aggressiveness hormone, were manipulated. The effects of increased corticosterone levels on reproductive performance and output were also evaluated during the chick-rearing period. Finally, the behavioural consequences of a moderate elevation of corticosterone levels during the whole breeding cycle were assessed. On the whole, an increase in corticosterone levels decreased reproductive performances and output. Changes in prolactin or testosterone levels affected incubation duration and egg temperature, suggesting a role for these hormones in the control of the timing of breeding. The results prevented in this PhD highlight the fact that the relationship between endocrine status and reproductive performance is dose-, state-, and context-dependant. Our results illustrate the major role of the hormones considered in our studies in the regulation of reproductive effort. They also underline the importance of considering the interactions of organisms with their environment in studies of animal behaviour and ecophysiology.

Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-03-05T18:27:51Z No. of bitstreams: 2 Fernando_Martins2017.pdf: 3146180 bytes, checksum: a1dcde101c1559cda9b93c488d0f17e9 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-05T18:27:51Z (GMT). No. of bitstreams: 2 Fernando_Martins2017.pdf: 3146180 bytes, checksum: a1dcde101c1559cda9b93c488d0f17e9 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / For species that do not exhibit parental care such as oviparous insects, choosing a favorable oviposition site is of utmost importance for brood success. Niche theory predicts that crickets should show a bell-shaped oviposition response to substrate humidity. However, at least one lab experiment with mole crickets (Orthoptera: Gryllotalpoidea) indicated a linear oviposition responses to substrate humidity. The house cricket Acheta domesticus (Orthoptera: Grylloidea) also shows a linear juvenile body growth response to substrate humidity, which suggests a positive relationship between humidity and oviposition preference. We evaluated the relationship between oviposition frequency and substrate humidity in forest litter- dwelling species, primarily composed of Ubiquepuella telytokous, using field experiments. We also tested oviposition responses of U. telytokous to substrate humidity in a laboratory experiment. We offered oviposition substrates that varied in humidity from zero percent to maximum substrate water absorption capacity. Oviposition preference was estimated using presence or absence of eggs as a binary response variable, adjusted logistic regression (GAMM) was used to test for non-linear responses, and GLMs were used to test linear responses. We found that oviposition probability increased linearly with substrate humidity for U. telytokous in both field and lab experiments. Our results demonstrate the importance of substrate humidity as an ecological niche requirement for this species. This work bolsters knowledge of litter cricket life history association with humidity, and suggests that litter crickets may be particularly threatened by changes in climate that favor habitat drying. / Para espécies que não apresentam cuidados parentais, tais como insetos ovíparos, a escolha de um local de oviposição favorável é de extrema importância para o sucesso da prole. A teoria do nicho prevê que a oviposição de grilos deve mostrar uma resposta em forma de sino à umidade do substrato. Entretanto, pelo menos um experimento de laboratório com paquinhas (Orthoptera: Gryllotalpoidea) indicou uma resposta de oviposição linear em relação a umidade do substrato. O grilo doméstico Acheta domesticus (Orthoptera: Grylloidea) também apresenta um crescimento corporal dos juvenis linear em relação a umidade do substrato, o que sugere uma relação positiva entre umidade e preferência de oviposição. Aqui testamos a relação entre a frequência de oviposição e a umidade do substrato, em espécies de grilos de serrapilheira florestal, primariamente compostas Ubiquepuella telytokous, utilizando experimentos de campo. Também testamos as respostas de oviposição de U. telytokous em experimentos de laboratório. Oferecemos substratos de oviposção que variaram a umidade de zero porcento até a capacidade máxima de absorção do substrato. A preferência de oviposição foi estimada utilizando presença ou ausência de ovos como uma variável resposta binária, regressão logística ajustada (GAMM) para testar respostas não lineares, e GLMs para testar respostas lineares. Verificamos que a probabilidade de oviposição aumenta linearmente com a umidade do substrato para U. telytokous, nos experimentos de campo e laboratório. Nossos resultados demonstram a importância da umidade do substrato como requisito de nicho ecológico para Ubiquepuella telytokous. Este trabalho reforça o conhecimento da associação de história de vida de grilos com a umidade, e sugere que esses organismos podem ser particularmente ameaçados por mudanças climáticas que tornam habitats áridos.