Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 18 of 18 for “"Trophic Niche"”.
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Characterizing the trophic niche of non-native psedorasbora parva and the consequences for native fish communities.
… introduction of a model non-native fish on the trophic position and trophic niche size of native fishes were investigated, along with assessment of the mechanisms of resource partitioning or sharing between the co-existing species. The model non-native fish was topmouth gudgeon Pseudorasbora …
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Small scale hydrogeomorphic features influence macroinvertebrate food webs in two Great Plains rivers
… δ13C in the food web, consumer resource use, trophic community metrics and size corrected standard ellipse area (SEAc) a measure of consumer niche breadth. I found river sinuosity and percent fine grain sediment to have a large influence on the food web. Increasing sinuosity was associated …
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Behavioural ecology of lesser sheathbills Chionis minor at Marion Island
… and predators. The adaptiveness of the broad trophic niche was investigated. A hypothesis that the variable social behaviour facilitated exploitation of variable food resources to benefit individual birds was examined; particular attention was paid to territoriality among breeding (summer) and …
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Systematics, Phylogeography and Ecology of Elaphomycetaceae
… we examined the possible effects of asexuality, trophic niche, dispersal method, and ocean barriers on population structure. In Chapter 2, we examine the systematics and phylogeography of the Elaphomycetaceae, a family consisting of the truffle genus Elaphomyces and the stalked genus …
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Ecological consequences of non-native parasites for native UK fishes.
… over a 12 month period. Differences in the trophic ecology of the infected and uninfected components of the host populations were identified using stable isotope analysis and associated metrics, and revealed considerable differences in the trophic niche breadth of the infected and uninfected …
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Stable isotope ecology of South African kelp forests
… web characteristics, with particular focus on trophic structure and functioning. SIA can be used to understand the basal isotope variability in producers, determine the primary carbon sources of food webs, and investigate the spatial and temporal patterns in consumer isotope values and trophic …
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Niche Occupancy, Partitioning, and the Role of Trophic Flexibility in Coexistence of Neotropical Bats
Understanding niche occupancy of an organism is critical to understanding its role in the environment, and how it persists as compared to others. In animal studies, the trophic niche is often used as a simplification of the Hutchinsonian realized niche. Trophic flexibility is a common strategy …
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Trophic Dynamic Interactions in a Temperate Karst River
… DIC availability in larger watersheds? 2. Are trophic niche breadths narrower in more karstified reaches than in less karstified reaches due to longitudinal differences in Cladophora standing stocks? 3. Do differences in trophic-dynamic relationships between primary consumers and their food …
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Fish Assemblage Structure, Trophic Ecology, and Potential Effects of Invading Asian Carps in Three Missouri River Tributaries, South Dakota
… that Silver Carp and Gizzard Shad overlapped trophically and the isotopic trophic niche of Emerald Shiner, which is usually pelagic, potentially moved to more benthic habitats and food sources as a result of Silver Carp presence. There were no perceived effects of Silver Carp on Bigmouth …
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Modelling and empirical approaches for predicting the invasiveness of alien species.
… empirical approaches in Chapter 5 predicted the trophic impacts of a globally invasive fish on a threatened native fish, with aquaria experiments and experimental ponds predicting that the global invader will substantially impact the trophic ecology of the native species (trophic niche shifts, …
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Utilizing an Integrated Approach to Explore Niche in a Complex Equatorial System
… rich tapestry of life seen on Earth. The term "niche" describes how animals partition resources in space and time, shaped by behavioural choices and environmental conditions. Iterations of niche over time have focused on different aspects of a species' ecological characteristics, from Grinnell’s …
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The foraging ecology and conservation of the Great Black-backed Gull Larus marinus
… indirect impacts such as the destabilisation of trophic relationships between predators and prey, leading in turn to predator-prey conflicts within seabird communities. Monitoring the abundance of seabird species and advancing our knowledge of their foraging ecology is therefore fundamental to …
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Population ecology and behaviour of European barbel Barbus barbus, a recreationally important, translocated fish.
… This was followed by investigating the B. barbus trophic relationships with other cyprinid species, and in relation to angling. In addition, the tracking of B. barbus in the lower river provided insights into the behaviours of individual fish. The majority of the spawning gravels analysed in the …
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Applied ecology and management of a European barbel Barbus barbus population of a lowland river
… (including the Great Ouse) to determine the trophic relationships of the fishes using stable isotope analysis. Outputs indicated that scales can be used for this analysis and revealed that rather than sharing food resources with functionally similar species such as chub Squalius cephalus, B. …
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Ecological consequences of indigenous and non-indigenous freshwater fish parasites.
… fishes, and revealed consistent patterns of trophic niche divergence between infected and uninfected population sub-groups. Whilst the actual mechanism underpinning this, such as parasite-mediated competition, could not be tested, these results did reveal that the consequences of infection …
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Influence of riparian forest and agricultural land use on community structure and ecosystem function in headwater streams
… all three land use groups due to differences in trophic structure. In addition, the fish assemblage matrix was significantly correlated to environmental patterns that clustered streams into each land use group. Macroinvertebrate assemblages were less sensitive to land use changes at both the …
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Bycatch and foraging ecology of sea turtles in the Eastern Pacific
… of three species of sea turtles to compare trophic status and to observe if spatial patterns were shown in the SIA signatures of sea turtles. To our knowledge this is the first study employing SIA to research the ecology of three species of sea turtles from the same time and space. Our …
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TROPHIC ECOLOGY OF JUVENILE LEAN AND SISCOWET LAKE TROUT (SALVELINUS NAMAYCHUSH) FROM U.S. WATERS OF LAKE SUPERIOR
… spatial overlap, diet similarity, and isotopic niches of juvenile Lean and Siscowet Lake Trout ecotypes across six ecoregions of Lake Superior. Spatially, Lean and Siscowet were observed in overlapping depth distributions. Leans were most abundant in shallow waters (60m). The greatest levels of …