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MacNeil, M. Aaron. "Robust analysis of reef fish communities." Thesis, University of Newcastle Upon Tyne, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443102.
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Davey, Andrew J. H. "Competitive interactions in stream fish communities." Thesis, University of Southampton, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274580.
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Henriksson, Anna. "Biotic resistance in freshwater fish communities." Doctoral thesis, Umeå universitet, Institutionen för ekologi, miljö och geovetenskap, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-110251.
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Invasions of non-native species cause problems in ecosystems worldwide, and despite the extensive effort that has been put into research about invasions, we still lack a good understanding for why some, but not other, communities resist these invasions. In this doctoral thesis I test hypotheses on biotic resistance using a large dataset of more than 1000 both failed and successful introductions of freshwater fish into Swedish lakes. We have found that the classic species richness hypothesis is a poor descriptor of introduction success because it fails to acknowledge that resident species contribute to the resistance in different ways. We developed a new measure of biotic resistance, the weighted species richness, which takes into account that the resident species contributes to the resistance with different strength and sign. Further, we correlated performance traits of species in their role as an invader and as a resident species to predict how the biotic resistance of these communities would develop over time. We found a positive correlation between performance traits: Some species have high introduction success, they make a large contribution to the resistance, and they cause extinctions when introduced but do not go extinct themselves when other species establishes, whereas other species are weak performers in these respects. Thus, the biotic resistance of these communities should grow stronger as non-native species accumulates. These results give us clues about what type of communities that should be most sensitive to further invasions, i.e., communities harboring species weak performers. My results show that the biotic resistance of communities is an important factor in determining invasibility of a community. They also show that methods for quantifying resistance must take into account how interactions are structured in nature. What determine the biotic resistance of a community is the type of interactions that the resident species have with the invader and not the species richness of the community.
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Whitfield, Kelly. "Stanley Fish: Interpretation and interpretive communities." Thesis, Whitfield, Kelly (1995) Stanley Fish: Interpretation and interpretive communities. Masters by Coursework thesis, Murdoch University, 1995. https://researchrepository.murdoch.edu.au/id/eprint/52839/.
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This dissertation is a critique of the general theory that Stanley Fish presents in his two books, Is There A Text In This Class: The Authority Of Interpretive Communities, and Doing What Comes Naturally: Change, Rhetoric and the Practice of Theory in Literary and Legal Studies. The importance of the theories presented in these two books is of wider-ranging importance than just the literary and legal academy, which is, at first glance, what Stanley Fish appears to be writing about. Stanley Fish uses these fields as a starting point to discuss interpretation of the text. However, he claims that his arguments have a wider relevance, and can explain the nature of all interpretations of the world around us. Both the legal and literary academies make claims about the nature of interpretation of texts. The history of both fields is full of discussion over what should be regarded as the best method of interpretation of any particular text, with various reading strategies being proposed as being the most objective. Fish’s point of view, however, is that no interpretation can be truly objective, although he also claims that this point of view does not commit him to a position where all interpretation is subjective. He refuses the traditional dichotomy between these two terms. The key to this apparent paradox is in the use of his concept interpretive communities.
Stanley Fish proposes interpretive communities as a coherent social system of meaning which explains how interpretation, whilst not being objective in the pure sense of the term, is nevertheless not subjective. Fish’s explanation of interpretive communities has been subject to a great deal of criticism, and this dissertation will first summarize both Fish’s view, and that of some of his critics, then will discuss whether Fish’s arguments prove what he says they prove, or whether his critic’s objections prevail.
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Pennock, Casey A. "Fragmentation and fish passage: can fishways mitigate discontinuities in Great Plains fish communities?" Thesis, Kansas State University, 2016. http://hdl.handle.net/2097/34557.
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Master of ScienceDepartment of Biology
Keith B. Gido
Fishways are a common tool for mitigating the effects of habitat fragmentation on fish communities, but their utility in low-gradient, sand-bed rivers of the Great Plains is not well studied. The Lincoln Street Fishway on the Arkansas River became operational in 2015 and was built specifically to pass small-bodied threatened fishes. We used a combination of surveys up-and downstream of the barrier and tagging experiments to test the ability of fishes to move into and through the fishway. Differences in fish community structure up- and downstream of the dam were more pronounced prior to the construction and operation of the fishway. In particular, Emerald Shiner Notropis atherinoides was absent from collections upstream of the dam before fishway construction, but commonly collected upstream in 2015 and 2016 surveys. Surveys within the fishway structure revealed 29 species, or 74% of the total species captured during our study were using the fishway. To further quantify fishway passage, we used a VIE experiment to assess if fish marked downstream of the fishway moved into or upstream of the fishway. Although we did not recapture marked fish upstream of the fishway, some marked individuals moved into the fishway. Finally, we conducted a PIT tag experiment to evaluate short distance movements within the fishway for three species of small-bodied minnow and were able to document upstream movement across a gradient of flows through the fishway. Results from our study illustrate the potential for fishways to mitigate the effects of habitat fragmentation on small-bodied fishes in sand-bed rivers.
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Beugly, Jayson S. "Fish and invertebrate communities in agricultural headwater streams." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1391472.
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Agricultural practices may influence stream biological communities by removing riparian vegetation and modifying stream channel morphology, both which may reduce water retention time. I collected benthic invertebrates and fishes in seven headwater agriculturally-influenced streams in central Indiana, to quantify controls on invertebrate and fish community assemblage variation. Invertebrates were collected at 14 sites and fish were collected at 12 sites in Buck Creek watershed. The abundances of invertebrates and fishes were analyzed in Detrended Correspondence Analyses (DCA) in PC-ORD software and correlated with abiotic and biotic factors. The sites located in close proximity to Buck Creek have increased stability of biotic (fish assemblages) and abiotic (flow and water depth) factors. Abundances of invertebrates of headwater streams in east-central Indiana agricultural landscapes are influenced by distance between sites, distance to Buck Creek, and presence of fish species. Abundances of fishes were correlated with water quality and distance to Buck Creek.Department of Biology
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Panikian, Garabet. "Statistical modelling of marine fish populations and communities." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/17063/.
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Sustainable fisheries management require an understanding of the relationship between the adult population and the number of juveniles successfully added to that population each year. The process driving larval survival to enter a given stage of a fish population is highly variable and this pattern of variability reflects the strength of density-dependent mortality. Marine ecosystems are generally threatened by climate change and overfishing; the coupling of these two sources have encouraged scientists to develop end-to-end ecosystem models to study the interactions of organisms at different trophic levels and to understand their behaviours in response to climate change. Our understanding of this important and massively complex system has been constrained historically by the limited amount of data available. Recent technological advances are beginning to address this lack of data, but there is an urgent need for careful statistical methodology to synthesise this information and to make reliable predictions based upon it. In this thesis I developed methodologies specifically designed to interpret the patterns of variability in recruitment by accurately estimating the degree of heteroscedasticity in 90 published stock-recruitment datasets. To better estimate the accuracy of model parameters, I employed a Bayesian hierarchical modelling framework and applied this to multiple sets of fish populations with different model structures. Finally, I developed an end-to-end ecological model that takes into account biotic and abiotic factors, together with data on the fish communities, to assess the organisation of the marine ecosystem and to investigate the potential effects of weather or climate changes. The work developed within this thesis highlights the importance of statistical methods in estimating the patterns of variability and community structure in fish populations as well as describing the way organisms and environmental factors interact within an ecosystem.
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Zha, Yinghua. "Assembly of Gut Microbial Communities in Freshwater Fish and Their Roles in Fish Condition." Doctoral thesis, Uppsala universitet, Limnologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-314235.
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Animal hosts provide associated microorganisms with suitable ecological niches in their intestines. Microbes help their hosts to digest food, protect against pathogens, and influence the host’s metabolisms. Compositional variation of gut microbial communities is common among hosts, and may affect the health status of hosts. Diet and genetic factors are well known to influence the assembly of gut microbial communities. This thesis focuses on disentangling the contributions of factors including host genetics (sex), diet, environment, and other ecological processes to the assembly of gut microbial communities in freshwater fish. The association between gut microbial communities and fish condition is also evaluated in this thesis. Applying metacommunity theory, we found environmental factors including fish habitat, fish species, their diet, dispersal factors including microbes from fish diet, and ecological drift contributed to the assembly of fish gut microbial communities. The proportion of their contribution varied between fish species, where ecological drift explained more in perch than in roach. Under natural conditions fish populations face the risk of predation, which can induce competition and impose predation stress within prey individuals. This can therefore lead to changes in their diet qualities and quantities. In this thesis, it was shown that fish diet in terms of qualities and quantities significantly influenced the overall gut microbial composition, and this influence was dependent on fish sex, a host genetic factor. Predation stress was also suggested to significantly decrease the species richness. Furthermore, when fish were experiencing a diet shift, we showed that different bacterial phyla from novel food had different colonization success in the intestine, and this colonization success was positively influenced by predation stress. Fish condition was suggested in this thesis to be affected by gut microbial composition, especially by the contributions of the bacterial phyla Tenericutes and Actinobacteria.
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Xu, Yi. "Modeling the Seasonal and Interannual Variability of Peruvian Anchovy (Engraulis ringens) Population Dynamics: Linking Environmental Conditions with Fish." Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/XuY2009.pdf.
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Carlson, William E. "Evaluating hydrologic controls on fish and macroinvertebrate communities in Ohio's western Allegheny Plateau." Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1149193823.
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Murphy, Stephen J. "Assessment of fish and plant communities in Lake Apopka, Florida." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0012980.
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Smith, Michelle Anne. "Outcomes of river rehabilitation on instream hydraulics and fish communities." Thesis, University of Hull, 2013. http://hydra.hull.ac.uk/resources/hull:8125.
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All fish species have specific habitat requirements, which differ according to life history and life stage. Where requirements are not met, or are inadequate for a particular species, the species will be locally absent or the population in poor condition and abundance. As a result of numerous anthropogenic stressors, river systems, and consequently fish physical habitat, have undergone considerable transformation, frequently resulting in homogenisation of the river channel, often to the detriment of the fish biota present. Following the emergence of the EC Water Framework Directive (WFD) and EC Habitats Directive (HD), there has been an increase in river rehabilitation schemes to ameliorate anthropogenic pressures of rivers and augment ecological status to meet specific obligations. However, despite the extensive implementation of river rehabilitation programmes little follow up monitoring, and dissemination of results takes place leaving a paucity of information on the outcomes of such schemes on in stream hydraulic conditions and fish community composition. Four river rehabilitation schemes on three UK Rivers were monitored to assess the effects of the schemes on instream hydraulic conditions and fish community composition and structure. Variation of instream hydraulics was assessed before and after the rehabilitation to investigate the environmental outcomes of river rehabilitation schemes. Little significant change in hydraulic conditions was observed following river rehabilitation at all sites surveyed although a significant decrease in depth and a significant increase in flow velocity was observed at the most upstream site following weir removal from the River Dove at Dovedale. Little change in fish species composition was observed following river rehabilitation at all sites. Given the importance of physical habitat to fish, surveys were conducted on a meso-scale in heterogeneous rivers to assess differences in hydraulic conditions and fish species composition of different habitat types. Glides were generally deeper than riffles, with fish species composition dominated by >1+ brown trout whereas riffles were generally shallower than glides. The composition of the fish community in riffles generally contained a greater proportion of bullhead and 0+ brown trout than glides. Due to the importance of fish as an indicator of ecological quality under WFD guidelines, it is imperative to understand the intricate linkages between fish species and hydraulic habitat. Habitat use of all species captured was investigated and despite similarity in the range of values measured, different preferences were shown by different species. The relationship between descriptors of fish community composition and measures of hydraulic habitat were also investigated and revealed that individual hydraulic parameters have little influence over fish community composition.
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Fielding, Nicola Jane. "Fish and benthos communities in regenerated dock systems on Merseyside." Thesis, University of Liverpool, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.482788.
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Restored docks have high amenity, tourism and recreational value. Polluted and unaestheticw ater is a major factor potentially inhibiting redevelopmento f docklands, particularly if the source of water suffers from severe pollution problems. The aims were to examine spatial and temporal patterns of hydrography and ecology of Merseyside Docks. Strategies to develop benthic filter-feeders on both the walls and in the sediments were considered important in maintaining good water quality. In the South Docks, algal blooms were mainly small and short-lived and anoxia was infrequent. In Princes Dock (Central chain) water quality was very good. Morpeth Dock (Wirral chain) suffered from poor water quality. Anoxia resulted in high mortalities of dock fauna and fish and the release of hydrogen sulphide gas. Algal blooms were very large and were maintained over long periods. The dinoflagellate, Prorocentrum minimum, was particularly prevalent. Zooplankton have remained at relatively low densities in the South Docks, particularly in Albert Dock (South chain), probably because of strong competition for food with benthic filter-feeders. In contrast, Morpeth Dock has maintained much higher numbers, probably because of the plentiful food supply and absence of benthos. The benthos of the walls was surveyed. Mytilus edulis is most prominent in Albert and Queens Docks; Ciona intestinalis and Ascidiella aspera are most abundant in Albert and Princes Docks; and, Molgula manhattensis dominant in Brunswick and QueensD ocks. Tiles have been used to follow the pattern of annual successiona nd the effect of timing of available space on this pattern of succession. In contrast to previous years when there had been very little recruitment of Mytilus to the South Docks, Mytilus settlement occurred in Queens Dock during autumn 1995. Experiments aimed at increasing the filter-feeding capacity by introducing Cerastodermae dule (common cockle) and manipulating particle size of the sediment concluded that cockles do not survive in the dock, probably due to occasional low oxygenc on centrations in the hypolimnion, and modification of sediment has very little effect on natural colonization. Experiments examined the impact of filter-feeders on phytoplankton numbers and regeneration of nutrients. Mytilus was shown to have higher clearancer ates( cell mV h' int) than its major competitors( Ciona intestinalis, Styela plicata) on the dock wall. The experiment investigating nutrient release by Mytilus indicates release of phosphate. Fish communities in the South Docks were relatively diverse, with a total of fifteen species of fish being caught. The size/frequency analyses suggest that the majority of fish were juveniles. The occurrence of two sea trout (Salmo trutta) indicates a return of salmonids to the estuary. The use of a capacity model as a management tool is proposed; this has been fitted to the South Docks system with some success.
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Aiken, James. "Impact of piscivorous fish introduction on fish communities of small temperate lakes in Gatineau Park, Quebec, Canada." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28286.
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Small temperate lakes are under increasing pressure from a number of anthropogenic sources, including but not limited to: habitat alteration, invasive species, climate change, and pollution. In Gatineau Park, Quebec, Canada small temperate lakes have been demonstrated to be under threat from introduced piscivores, among other potential stressors. Here, I assessed the historical impact of four introduced piscivores on minnow, small fish and total fish species richness for a set of small Gatineau Park lakes. Fish community data were obtained from two previously published studies and a lake survey conducted in the summers of 2006 and 2007. I used a modified Control/Impact study design and repeated measures analysis of variance to test the hypothesis that introduced piscivores negatively affect species richness over time. My results strongly demonstrate that piscivores have had a negative effect on minnow and small fish species richness over time, whereas total fish species richness was unaffected. Assuming that these introduced piscivores pose a risk to the parks small temeprate lakes, I then assessed what lake characteristics best predict piscivore invasion risk. To do this, I estimated invasion risk employing two different analytical approaches for a total of 42 small lakes located in Gatineau Park using current and historical data collected in 1971, 1981, 1991 and 2006. Bootstrapped logistic regression was used to predict historical occurrence, and whether or not a lake was invaded/not invaded over time using predictor variables that included lake anthropogenic, spatial-isolation, and morphometric factors. For both logistic regression analyses, lake area and small fish species richness were found to be excellent predictors of piscivore invasion risk and historical occurrence, while lake spatial-isolation factors were also found to be excellent predictors of piscivore historical occurrence. The bootstrapped models with the most support based on Akaike's Information Criterion corrected for small sample size (AICc) were then used to identify lakes at greatest risk for future invasion. My results support the contention that introducing top predators into novel aquatic environments has detrimental impacts on native fish communities, and that these impacts are not always immediately obvious, but are indeed discernable over time. In conclusion, I make specific recommendations to guide the conservation and management of small temperate lake ecosystems.
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Sweet, Diana E. "Movement patterns and habitat associations of native and introduced catostomids in a tributary system of the Colorado River." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1445041561&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Lam, Fung-ngai. "Spatial and seasonal patterns in community structure of tide-pool fishes in Hong Kong /." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B24533336.
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Yahya, Saleh A. S. "Habitat structure, degradation and management effects on coral reef fish communities." Doctoral thesis, Stockholms universitet, Zoologiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-62187.
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Coral reefs are among the most diverse and productive ecosystems on earth, and are critical to the survival of tropical marine ecosystems and sustenance of local human populations. However, coral reefs are quite vulnerable to disturbances, both natural and anthropogenic. This thesis looks at how coral reef communities have responded to climactic disturbances, particularly the 1997-98 El Niño Southern Oscillation (ENSO) and subsequent coral bleaching and mortality that affected much of the Indian Ocean, including the coastal waters of Tanzania, where the study was conducted. In particular, it investigates the effects of coral bleaching, habitat degradation and reef spatial arrangement on reef fish assemblages. Habitat structural complexity and spatial arrangement of reefs had an effect on reef fish communities. Fish communities showed patterns in distribution among habitats and between patch and continuous reefs. Fishes preferred live to bleached/dead or eroded coral, but trophic groups reacted differently to patch and continuous reefs. There were slight changes in fish abundance and significant changes in fish diversity on experimental, bleached branching Acropora coral plots over a period of one year. While fish abundance on one site increased shortly after a bleaching event, 6 years later fish abundance had decreased significantly. Conversely, coral reef communities in northern Tanzania had changed little over an 8-year period, with minor changes associated with the 1997-98 ENSO and the presence or absence of fisheries management. The coral reefs in the region were found to show high variability in community structure and responses of associated fish and invertebrate communities. The findings of this thesis indicate the importance of habitat structure and spatial arrangement of reefs, the detrimental effects of coral bleaching, and the possibility that some reefs and some (generalist) reef fish taxa may exhibit resilience to climate change.At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.
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Miyazono, Seiji. "PATTERNS OF FISH COMMUNITIES AND LIMNOLOGICAL CONDITIONS RELATIVE TO FLOODPLAIN LANDSCAPES." MSSTATE, 2008. http://sun.library.msstate.edu/ETD-db/theses/available/etd-07082008-161716/.
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The Yazoo River Basin of Mississippi includes several rivers and hundreds of floodplain lakes within an area greatly impacted by agriculture. I studied 17 of these lakes distributed over the lower half of the Yazoo River Basin to document fish assemblages and limnological patterns and to identify environmental variables that might influence these assemblages. Potential connectivity of the lake to parent river and wetland-lake area ratio in the watershed were related to the limnological conditions and fish communities. Lakes with greater potential connectivity tended to be deeper and had greater specific conductance and greater fish species richness including more riverine species. Conversely, as the potential connectivity decreased, lakes were shallower, had greater chlorophyll-a fluorescence, wetland-lake area ratio, and a less speciose lacustrine fish community. Species richness and assemblage composition of riverine species were related directly to potential connectivity. Lacustrine species assemblages were linked to wetland-lake area ratio and turbidity.
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Baldwin, Elizabeth Anne. "Examination of the coarse fish communities in two artificial standing waters." Thesis, University of Manchester, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.704744.
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Dawson, Steffany. "Juvenile Pelagic Fish Communities in the Mattaponi and Pamunkey Rivers, Virginia." W&M ScholarWorks, 1992. https://scholarworks.wm.edu/etd/1539617648.
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Holt, T. D., Phillip R. Scheuerman, and Kurt J. Maier. "Long-Term Road Construction Impacts on Water Quality and Fish Communities." Digital Commons @ East Tennessee State University, 2003. https://dc.etsu.edu/etsu-works/2936.
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Kilgour, Bruce William. "Fish-benthos correlations and effects on benthos that reflect significant effects on fish communities in southern Ontario streams." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq22213.pdf.
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Smith, Scott A. 1978. "The importance of regional and historical processes in the assembly and maintenance of lower Mesoamerican freshwater fish communities /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80875.
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The relative importance of local, regional and historical processes to patterns of distribution and diversity of lower Mesoamerican (Panama and Costa Rica, LMA) freshwater fishes are examined at two different spatial scales. Biogeographic patterns of LMA freshwater fish communities at the spatial extent of LMA indicate that biological differences among species as well as regional and historical processes are quintessential to explaining the patters of turnover of community composition and species richness across the LMA Isthmus. The study of LMA freshwater fishes permits the inference that ecological interactions among species are not independent of a region's history, suggesting that regional and historical processes probably play an ongoing role in the maintenance of LMA freshwater fish communities. In addition, the study of the natural experiment of the Panama Canal provides a clear demonstration that dispersal, rather than local deterministic processes such as competition and predation, previously set the upper limit of the number of fish species coexisting in local communities. Comparisons of species inventories established prior to Canal construction with contemporary species lists demonstrates a large net increase in species richness of local communities, suggesting that the local communities of the Panama Canal watershed were not saturated.
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Wilson, Andrew Stewart. "The effect of piscivorous fish stocking on the planktivorous fish, zooplankton, and phytoplankton communities of 31 southeastern Ontario lakes." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/10417.
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Over the past 15 years a great deal of literature has been generated in an attempt to understand the regulation of trophic level biomass and size structure in aquatic systems. I tested the hypotheses that the among-lake variability in biomass and size structure of planktivorous fish, zooplankton, and phytoplankton communities depends on: (1) resource availability (bottom-up processes); (2) piscivorous sport fish stocking (top-down processes); and (3) the particular species of piscivorous sport fish stocked. We sampled 31 lakes in southeastern Ontario over the summers of 1993 and 1994 to obtain indices of abundance, biomass, and size structure of the planktivorous fish, zooplankton, and phytoplankton communities. Seven of the lakes were not stocked and the remaining 24 had stocking intensities ranging from 30 to 1500 individuals stocked per hectare over the 6 years prior to sampling. For both bottom-up and top-down analyses, trophic interactions were strongest at the base of the food web and weakened at higher levels, becoming non-significant thereafter. From these results I conclude that: (1) piscivorous sport fish stocking as a whole (at least at the magnitude examined here) had no effect on planktivorous fish, zooplankton, and phytoplankton biomass or size structure; (2) rainbow trout (Oncorhynchus mykiss) stocked lakes differ at the zooplankton and phytoplankton level from lakes stocked with other species of piscivore; (3) trophic interactions are most evident at the base of the food web (at the zooplankton and phytoplankton level); and (4) resource control (especially total phosphorus) of biomass and size structure in aquatic communities is much more important than consumer control, and it is limited to the phytoplankton and zooplankton. Our results suggest that stocking with piscivorous fish (as practised for sport fishing purposes) does not effectively manipulate plankton abundance. (Abstract shortened by UMI.)
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Zagars, Matiss. "Estuarine mangrove fish communities in southwestern Thailand : trophic ecology and movement patterns." 京都大学 (Kyoto University), 2012. http://hdl.handle.net/2433/160976.
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Irving, Philip William. "The functional and evolutionary significance of Schreckstoff in natural communities of fish." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307984.
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Kemp, Jeremy Mark. "The biogeography of coastal fish communities and associated habitats in southern Arabia." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301157.
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Hazellief, Blythe. "Effects of Agricultural Land Use on Stream Fish Communities in Ohio, U.S.A." Wright State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=wright1453153347.
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Henderson, Christopher. "Seascape Context and Marine Reserves in Seagrass Ecosystems: Managing Harvested Fish Communities." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/365948.
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Marine ecosystems are undergoing rapid change from a suite of human-induced stressors including overexploitation of resources, habitat fragmentation and loss, reduced habitat quality and changes to ecosystem functioning. Reserves are implemented and designed to reduce these influences, by preserving biodiversity, conserving marine habitats, increasing resilience of biota to disturbances, enhancing productivity, and facilitating the recovery of exploited fishery species. Although marine reserves can alter the structure and functioning of ecosystems, other factors such as seascape context and temporal variability can influence fish communities, ultimately determining the effectiveness of marine reserves. Ecosystem processes, abundances of harvested species and the spatial use of marine reserves can be largely influenced by the spatial properties that make up an ecosystem and other environmental factors such as climate. Although there is growing recognition of these processes, many of the key ecological characteristics that occur in protected seagrass ecosystems remain hitherto unstudied. I, therefore, aim to assess the influence of seascape context and temporal variability relative to the effectiveness of marine reserves for the protection of harvested seagrass fish species and the functions they provide. Ultimately, this thesis aims to determine the most suitable form of management of fish communities within seagrass ecosystems.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Piette, Randal R. "Effects of flow regulation due to hydroelectric project operation on the structure of fish communities in Wisconsin's large river systems /." Link to abstract, 2004. http://epapers.uwsp.edu/abstracts/2004/Piette.pdf.
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Hummel, Stephanie Elizabeth. "Understanding the Relationships between Plant Communities, Fish Communities, and Sediment Chemistry in Pristine Shallow Lake Wetlands, Red Lake, MN." Diss., North Dakota State University, 2016. https://hdl.handle.net/10365/28126.
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Over 90% wetland loss in many areas of the United States has triggered extreme concern for declining biodiversity and loss of ecosystem services. Studies assessing ecological characteristics of unaltered wetlands are critical to interpreting potential responses to anthropogenic changes and how ecosystem characteristics and services might respond to future climate dynamics. Previous research shows fish and plant communities play an important role in shallow lake ecology by creating stability within the clear state. Understanding these mechanisms in a pristine setting is important for successful conservation and restoration. Our objectives, part of a long term monitoring study (2009-2015), were 1) Evaluate patterns in multi-element concentrations of pore water along a gradient from upland areas through emergent vegetation to the open water of shallow lake wetlands 2) Assess seasonal changes of multi-element concentrations of pore water during the growing season of shallow lake wetlands 3) Measure the influence of fish communities species composition on plant communities species composition 4) Evaluate how sediment chemistry impacts plant communities. We evaluated pore water chemistry on two lakes using dialysis vials from June-October 2014. We selected 24 shallow lakes located within Red Lake Nation Indian Reservation, MN, USA to conduct the remaining objectives. At each lake we assessed fish community structure and abundance using fyke nets and experimental gill nets for a 24-hr period during July. Aquatic and emergent vegetation was assessed simultaneously by rake throws and Daubenmire frame, and sediment samples were collected by taking a surface grab sample. Sediment samples were taken in the open water and emergent vegetation zones. Pore water did not change across a gradient from upland to open water, but did change over the season from June to October. We found fish community composition did not change significantly from 2009 to 2015, but fish biomass significantly decreased from 2009 to 2015. No species-specific relationships between vegetation and fish existed, but species specific relationships existed between vegetation and sediment characteristics in both the open water and emergent vegetation zones. Results will be used as reference points for restoration and conservation, and serve for a better understanding of shallow lake state stability.Environmental Protection Agency (EPA)
Red Lake Band of Chippewa Indians Department of Natural Resources
Wet Ecosystem Research Group
North Dakota State University (NDSU)
North Dakota State University. College of Graduate and Interdisciplinary Studies. Environmental and Conservation Sciences Program
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Hammond, Tim R. "Classification of fish schools from acoustic survey data /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/5351.
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Mattsson, Emma. "Importance of Fucus vesiculosus (bladderwrack) for coastal fish communities in the Baltic Sea." Thesis, Stockholms universitet, Institutionen för ekologi, miljö och botanik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-176300.
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Within temperate coastal seascapes, macroalgae provide habitats for different organisms such as invertebrates and fish. In analogy to seagrass meadows, macroalgae beds are known for their importance as fish nurseries. However, within the Baltic Sea the importance of the canopy forming macroalgae Fucus vesiculosus for coastal fish communities, especially the juveniles, is unclear. In order to address this knowledge gap, fish communities in areas with and without F. vesiculosus were investigated around Askö, an island in the archipelago of the Baltic Sea. Sites were subjected to different exposures (sheltered, exposed or very exposed) and three different methods were used for sampling (underwater visual census (UVCs), beach seine netting and remote underwater videos (RUVs)). Overall, fish community composition differed significantly among locations and fish abundance and fish biomass were significantly higher in sites with F. vesiculosus than sites without. There was no significant relationship between algae cover or habitat complexity and fish abundance/biomass in sites with F. vesiculosus. Fish behaviour differed between sites with and without F. vesiculosus, with fish feeding more in sites with F. vesiculosus and traveling more in sites without F. vesiculosus. Only one location, Knabberskär, had significantly higher species richness in F. vesiculosus than in sites without F. vesiculosus. There were no differences in juvenile abundance among sites with or without F. vesiculosus and abundance of adult fish was higher than juvenile fish, regardless of location, site or species. Mean invertebrate abundance was a twice as high in the sheltered location Husbåtsviken than in Knabberskär. Higher fish abundance, fish biomass and species richness in sites with F. vesiculosus compared to sites without, suggest that macroalgae may play an important role in the Baltic Sea, however it might not be as important for juvenile fishes as predicted. The three different sampling methods provided similar results for fish abundance, but not for fish biomass. Continued studies where the relationship between fish communities and aspects of F. vesiculosus structure (such as canopy height) as well as linkage with other habitats is recommended for further understanding and better protection of F. vesiculosus habitats.
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Vila, Martínez Núria. "Effects of flow regime on the fish communities of the lower Ebro River." Doctoral thesis, Universitat Rovira i Virgili, 2018. http://hdl.handle.net/10803/664726.
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Els ecosistemes aquàtics presenten una estreta connexió entre forces físiques i processos ecològics. Als rius, aquesta interacció física-ecologia és dirigida pel cabal, un dels factors principals que determinen la integritat biològica. La combinació de grans alteracions hidrològiques degudes a la regulació per preses i una creixent presència d’espècies al·lòctones, posa en perill les comunitats de peixos autòctons a la Península Ibèrica. L’objectiu d’aquesta tesi és explorar les relacions entre el règim hidrològic i les comunitats de peixos del tram baix de l’Ebre per mitjà de l’anàlisi de dades de campanyes de pesca elèctrica realitzades durant més de 10 anys. Enfocàrem aquest objectiu des de tres punts de vista diferents: Al capítol 1 s’avaluaren les relacions entre les abundàncies de cada espècie i el règim hidrològic, mentre que als capítols 2 i 3, l’objecte d’estudi foren índexs de qualitat biològica basats en peixos i l’espectre de mides de la comunitat íctica, respectivament. Per descriure el règim hidrològic, férem servir un conjunt de variables calculades a partir de series diàries i horàries de cabals facilitades per la Confederació Hidrogràfica de l’Ebre (CHE). Els resultats mostraren la importància del cabal en determinar la composició íctica a nivell d’espècie, comunitat i estructura de mides. Aquests coneixements poden ser de gran utilitat pel desenvolupament d’eines de restauració ecològica i la conservació d’espècies de peixos, especialment en el context actual de creixents pressions sobre els ecosistemes d’aigua dolça (escalfament global, consum d’aigua i espècies invasores, entre d’altres).En los ecosistemas acuáticos se observa una estrecha relación entre fuerzas físicas y procesos ecológicos. En los ríos, esta interacción física-ecología está dirigida por el caudal, uno de los factores clave que determinan la integridad biológica. La combinación de grandes alteraciones hidrológicas debidas a la regulación por presas y una creciente presencia de especies introducidas, pone en peligro las comunidades piscícolas nativas de la Península Ibérica. El objetivo de esta tesis es explorar las relaciones entre el régimen hidrológico y las comunidades de peces del tramo bajo del Río Ebro mediante el análisis de datos de campañas de pesca eléctrica realizadas durante más de 10 años. Enfocamos este objetivo desde tres puntos de vista diferentes: En el Capítulo 1 se evaluaron las relaciones entre las abundancias de cada especie y el régimen hidrológico, mientras que en los capítulos 2 y 3, el objeto de estudio fueron índices de calidad biológica basados en peces y el espectro de tamaños de la comunidad ictiológica respectivamente. Para describir el régimen hidrológico, utilizamos un conjunto de variables calculadas a partir de series de caudal diarias y horarias facilitadas por la Confederación Hidrográfica del Ebro (CHE). Los resultados mostraron la importancia del caudal en la determinación de la composición ictiológica a nivel de especie, comunidad y estructura de tamaños. Estos conocimientos pueden ser de gran utilidad para el desarrollo de herramientas de restauración ecológica y conservación de especies de peces, especialmente en el contexto actual de crecientes presiones sobre los ecosistemas de agua dulce (calentamiento global, consumo de agua y especies invasoras, entre otras).
Aquatic ecosystems are characterized by a strong coupling between physical forcing and ecological processes. In rivers, this physics-ecology interaction is driven by flow, one of the main factors determining biological integrity. The combination of high flow alterations due to dam regulation and an increasing presence of alien species is endangering native fish communities in the Iberian Peninsula. The aim of this thesis is to explore the relationships between flow regime and fish communities in the lower Ebro River by analysing data from electrofishing campaigns collected during more than 10 years. We addressed this objective through three different approaches: On Chapter 1, the relationships between single species abundances and hydrological regime were evaluated while in Chapter 2 and 3 the objects of study were fish-based biological quality indices and size spectrum of fish community, respectively. To describe flow regime, we used a set of hydrological variables calculated from daily and hourly flow data series provided by the Ebro Basin Water authority (Confederación Hidrográfica del Ebro). The results showed the importance of flow in shaping fish composition at species, community and size structure levels. This knowledge may prove useful for the development of ecological restoration tools and fish species conservation, especially in a context of increasing pressures over freshwater ecosystems (global warming, water consumption and invasive species, among others).
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Viamonte, Louis David. "Five Mile Creek bioassessment study baseline evaluation of stream health using fish communities /." Birmingham, Ala. : University of Alabama at Birmingham, 2007. http://www.mhsl.uab.edu/dt/2007m/viamonte.pdf.
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Jordan, Linda Marie. "Characterizing mesophotic reef fish communities at five South Texas relic coral-algal banks." Thesis, The University of Texas Rio Grande Valley, 2016. http://pqdtopen.proquest.com/#viewpdf?dispub=10174034.
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The South Texas Banks are a mesophotic coral ecosystem (30-150m deep). Understanding the community structure, biodiversity and, geographic connectivity of the South Texas Banks is essential with increasing threats from climate change, ocean acidification, invasive species, and pollution. In this study, a remotely operated vehicle (ROV) was used to examine the fish communities at five of the South Texas Banks: Big Adam, Hospital, Mysterious, North Hospital, and Southern. Reef fish were identified to the lowest possible taxon and enumerated from ROV transect video footage. A total of 3,838 demersal and pelagic fishes were recorded representing 61 species in 22 families including invasive Pterois volitans. Bodianus pulchellus, Holocentrus adscensionis, Priacanthus arenatus, and the Gobiidae family were the only fishes observed at all five banks. Habitat suitability models were created that highlight the rich biodiversity found on the South Texas Bank, which will warrant for future research and conservation efforts.
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Guiet, Jérôme. "Environmental impact on fish communities in the global ocean : a mechanistic modeling approach." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT134/document.
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La biosphère marine joue un rôle fondamental dans la dynamique du Système Terre (cycle du carbone, composition atmosphérique, etc.) et rend un certain nombre de services essentiels à l’humanité (pêcheries, séquestration du carbone notamment). Sa vulnérabilité aux changements globaux (changement climatique, exploitation croissante des ressources naturelles et pollution en particulier) rend nécessaire et urgente l’anticipation de ses évolutions possibles. Dans cette perspective, il s’agira dans cette thèse d’étudier comment les écosystèmes marins sont structurés par leur environnement et comment cette structuration peut influer sur leur fonctionnement jusqu'à l’échelle de l’océan global. Dans un premier temps un cadre de modélisation a été développé pour prendre en compte l'impact de l'environnement des individus aux populations aux communautés. Il est basé sur un modèle de spectre de biomasse représentant les communautés de poisson en utilisant seulement la taille des individus et la taille maximum des espèces comme variables. Issu d'un modèle détaillé par Maury O. & Poggiale J.C. (2013) il est implémenté pour la représentation d'une communauté de poisson générique. Des indicateurs de structure, diversité et métabolisme sont développés pour étudier les écosystèmes ainsi représentés. Une fois le cadre méthodologique définit le modèle est utilisé pour l'étude idéalisée des propriétés du spectre de biomasse contraint par des conditions environnementales variables. L'impact de la variation de production primaire ainsi que la variation de température du milieu sont plus particulièrement étudiés. Tout d'abord en statique, c'est à dire en imposant différents niveaux constants. Indépendamment du forçage les communautés ont des propriétés similaires en augmentant la production primaire, en diminuant la température du milieu. Quatre domaines se succèdent en augmentant la production primaire, diminuant la température, à l'intérieur desquels les communautés de poissons ont des caractéristiques similaires. Les différentes propriétés dans les différents domaines induisent diverses sensibilités des écosytèmes à des niveaux de production primaire et/ou température distincts. Afin de lier les résultats de ces expériences numériques à la réalité, les propriétés des écosystèmes à différentes latitudes sont simulées. Le spectre de communauté est calculé le long d'une section latitudinale de l'équateur au pôle en forçant avec des niveaux moyens de production primaire et température. Les propriétés des écosystèmes ainsi représentés éclairent sur l'observation de tailles d'espèces croissantes de l'équateur aux pôles, la règle de Bergmann. Après ces résultats pour des spectres statiques, les propriétés dynamiques des spectres de communauté sont étudiées par l'étude de la saisonnalité. En forçant les communautés à différentes latitudes par un cycle saisonnier de production primaire et température, la succession d'espèces au sein de celles-ci joue un rôle sur les propriétés des communauté. Des pôles à l'équateur cette succession est plus ou moins marquée et impact la capacité des écosystème à maintenir les espèces les plus larges tout au long de la période de basse production entre deux blooms. Une fois les propriétés du spectre de biomasse évaluées de façon idéalisée, le modèle est implémenté dans le modèle d'écosystème APECOSM afin de prendre en compte les interactions spatiales et les interactions avec l'habitat. Appliqué à l'échelle de l'océan global et forcé par les champs physiques et biogeochimiques du modèle NEMO-PISCES il permet la modélisation des caractéristiques des écosytèmes en fonction de leur environnement. Différentes caractéristiques connues des écosystèmes marins sont reproduites, notamment la règle de Bergmann. Les modèles actuels décrivant le fonctionnement des écosystèmes marins ne comportent que des représentations très simplifiées de la biodiversitéThe marine biosphere plays a fundamental role in the earth system dynamics (carbon cycle, atmosphere composition, etc.) and provides numerous essential services to humanity (fisheries, carbon sequestration). Its vulnerability to global change (climate change, growing exploitation of natural resources, pollution) makes the study of its evolutions imperative. In this framework, the aim of this thesis is the study of the structuring of the marine biodiversity by hydro-climatic variability of the global ocean, as well as how this structuring impacts on the ecosystems functioning. First, a modelling framework is developed to account for the impact of environment from individuals to populations to communities. It is based on a biomass size spectrum model which represents fish communities with individuals size and species maximum length as only variables. Detailed in Maury O. & Poggiale J. C. (2013) the model is implemented to represent a generic fish community. Indicators of structure, diversity and metabolism are developed to study so represented ecosystems. Once the methodogical framework defined the model is used for the idealized study of the biomass size spectrum properties when constrained with different environmental conditions. The impact of distinct constant primary production and temperature levels are investigated. First the static impact, forcing ecosystems with constant levels. Communities present similar properties for increasing primary production or decreasing water temperature. A succession of four domains characterized by similar fish community features are observed with increasing primary production, decreasing temperature. These distinct charateristics will induce distinct sensitivities of ecosystems function of the level of primary production or temperature. In order to link the results of these numerical experiments to reality the properties of ecosystems along latitudes are also computed. The community biomass spectrum is simulated along stations at different latitudes from pole to equator forcing with mean primary productions and temperatures. The properties of so represented communities enlight the observation of increasing species length with latitude, the so called Bergmann's rule. After the results for static spectra, the dynamic properties of fish community spectra are analyzed through the seasonality. Forcing communities at different latitudes with a seasonal primary production and temperature cycle a more or less strong species sucession is observed. The succession impacts the capacity of communities to maintain larger species during the bad season of poor conditions between two peaks of primary production. Once the properties of the biomass community spectrum investigated in an idealized manner, the model is implemented in the ecosystem model APECOSM in order to account for the spatial interactions and the link with habitat. Applied in the global ocean and forced with physical and biogeochemical NEMO-PISCES domains the model allows the modelling of ecosystems characteristics. Different known characteristics of marine ecosystems are reproduced, especially Bergmann's rule. The current models describing marine ecosystems provide a simplified representation of biodiversity (e.g. NPZD type biochemical models, Ewe or Atlantis type box models, OSMOSE and APECOSM type models). It induces a limitation of their use in the study of the impact of climate change on biodiversity and reversely; for the study of the impact of biodiversity changes on the functioning of ecosystems. The model we describe mechanistically allows the representation of the dynamic of ecosystems from individual bioenergetic and predation interactions while keeping diversity
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Kapusinski, Douglas John. "Factors Affecting Invertebrate and Fish Communities in Coastal Wetlands of the Great Lakes." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1353202400.
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Carlson, William E. "Evaluating Hydrologic Controls on Fish and Macroinvertebrate Communities in Ohio’s Western Allegheny Plateau." Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1149193823.
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Howell, Charles E. "Correspondence between aquatic ecoregions and the distribution of fish communities of eastern Oklahoma." Thesis, Connect to this title online, 2001. http://www.library.unt.edu/theses/open/20011/howell%5Fcharles%5Fe%5Fjr/index.htm.
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Washko, Susan. "The Macroinvertebrate and Fish Communities of In-Stream Beaver Ponds in Northeastern Utah." DigitalCommons@USU, 2018. https://digitalcommons.usu.edu/etd/7395.
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Beavers were virtually extirpated from North America during the fur trade, but populations have since recovered. Dams built by recolonizing beaver alter stream habitat by forming deep, slow ponds within the streams. Such changes to the habitat is likely to have consequences for organisms such as macroinvertebrates and fish. The objective of this study was to identify the differences in the macroinvertebrate and trout community in beaver ponds and lotic (e.g. flowing reaches of a stream) reaches in tributaries to the Logan River in northeastern Utah. The macroinvertebrate community of beaver ponds had fewer species, fewer numbers, and lower biomass of macroinvertebrates compared to lotic reaches. Macroinvertebrates that consume leaf litter and predators that prey on other macroinvertebrates characterized beaver pond macroinvertebrate communities. In contrast, lotic reaches contained macroinvertebrates that consume algae and feed on particles floating through the water column. Macroinvertebrates in lotic reaches were morphologically adapted to cling to rocks in the streamflow, while those in beaver ponds were adapted to living within the fine sediment.
Bonneville cutthroat trout collected from lotic reaches were larger than those collected from beaver ponds, while the opposite was true for brown trout collected from lotic reaches. I also found that short-term and long-term diets of both brown trout and Bonneville cutthroat trout were similar between trout caught in beaver pond and lotic reaches. Finally, I found that growth rates of trout were also similar between the two habitats. In conclusion, the structure and function of macroinvertebrates, which are dependent on small-scale habitat features, were more affected by inclusion of beaver ponds to the stream network. Conversely, trout collected from beaver ponds and lotic regions were similar in growth and diet. Considering that beavers are used as a common restoration tool, further studies on the effects of beaver on stream communities is essential.
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Viau, Elizabeth C. "Fish Communities on Natural and Artificial Reefs in the Eastern Gulf of Mexico." Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7981.
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Artificial reefs have been deployed throughout the world’s oceans to act as habitat and fishing enhancement tools. To expand current research on the role of artificial reefs in the marine community, ordination and multivariate regression methods were used here to analyze survey data of natural and artificial reefs. The reefs, located in the Northern Gulf of Mexico (NGOM) and on the West Florida Shelf (WFS), had been previously surveyed from 2004 to 2015 using remote operated vehicle and stationary video techniques. This study tested the hypothesis that similar functional roles are accounted for at both natural and artificial reef sites even if species composition varies. Secondly, it examines the role of environment and fisheries in determining the assemblages. Artificial reefs tended to host communities that were as biodiverse as natural reefs, although not necessarily composed of the same species. Results of an ordination confirmed that as the classification was broadened from the level of species, to family, to functional group, the assemblages on each reef type (natural vs. artificial and NGOM vs WFS) appeared more similar. Dominant groups were present at all levels of classification and included the families Lutjanidae and Carangidae, as well as functional groups Red Snapper and Small Reef Fish. Both natural and artificial reefs tended to be dominated by one of the following: Lutjanidae, Carangidae, or Small Reef Fish, although a continuous gradient was found across the extremes of natural versus artificial reefs. Generalized Additive Models were developed to examine the influence of reef type, location, environment and fishing intensity covariates. Results indicated that for both natural and artificial reefs, the abundance of families and functional groups can be influenced by environmental factors. In both cases, there is strong spatial autocorrelation suggesting connectivity with neighboring reefs.
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Cathcart, Charles Nathan. "Multi-scale distributions and movements of fish communities in tributaries to the San Juan River." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18227.
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Master of ScienceDepartment of Biology
Keith B. Gido
Recognizing habitat needs of fishes across space and time is increasingly important for managing altered stream networks, such as in the Colorado River basin. Recent work on warm-water fishes suggest they might benefit from access to tributaries and their confluences. Fish movements or distributions within tributaries relative to distance from mainstem confluences in two streams with different network types (linear versus dendritic) were investigated in the San Juan River basin, USA. Upstream distance from the San Juan River resulted in species declines (Chaco Wash, linear network) or turnover (McElmo Creek, dendritic network). McElmo Creek movement patterns were likely attributed to spring spawning migrations of flannelmouth sucker (Catostomus latipinnis), spawning aggregations of razorback sucker (Xyrauchen texanus), foraging or refuge seeking by Colorado pikeminnow (Ptychocheilus lucius), and monsoon-related movements for channel catfish (Ictalurus punctatus) and razorback sucker. Razorback sucker and Colorado pikeminnow dominated movements at Chaco Wash, suggesting this backwater-like tributary supplied thermal or current refuge, foraging habitat, or both. Within McElmo Creek, a second study explored the importance of confluences by characterizing habitat use and movements of fishes at the junction of McElmo and Yellow Jacket creeks. Native fish dominated the confluence community composition. The reach downstream of the confluence had consistently higher abundances, species richness, and more frequent detections of tagged fishes relative to upstream reaches. Movement behaviors inferred by detection frequency of tagged fish among reaches surrounding the confluence differed among species. Small flannelmouth sucker (< 300 mm) and roundtail chub (Gila robusta) were commonly detected in Yellow Jacket Creek whereas large flannelmouth sucker (> 300 mm), bluehead sucker (C. discobolus), and channel catfish used McElmo Creek reaches. Monsoons increased McElmo Creek discharge which triggered upstream movements of channel catfish and displaced large flannelmouth sucker and bluehead sucker. Monsoons increased movements between McElmo and Yellow Jacket creeks by roundtail chub, small flannelmouth sucker, and black bullhead (Ameiurus melas). Combined, these two field studies emphasized using links between patterns and processes of tributary fish communities. Conservation, rehabilitation, and maintenance of connectivity and habitat heterogeneity at confluence zones likely can be a localized management strategy with expansive ecosystem effects.
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Mueller, Robert F. Jr. "Fish assemblages in the Wabash River : responses to substrate variation in field collections and artifical streams." Virtual Press, 2008. http://liblink.bsu.edu/uhtbin/catkey/1391677.
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Relationships between fish assemblage composition and substrate variation is poorly understood in large rivers. Information on fishes occurrence and behavior and substrate variation were examined in field observations for the Middle Wabash River and fine scale artificial streams experiments. The results from field observations suggested strong concordance for variation in abundance of fishes with habitat variation among sites, resulting in a longitudinal river gradient as dominant in the Middle Wabash River. In addition, shifts in fish behavior within artificial stream experiments demonstrated that species-specific habitat selection behaviors were influenced by interactions within a fish assemblage. The combination of artificial stream experiments and field observations can identify fine scale trends that bioassessment surveys cannot tease apart, and highlighting the need to examine species-habitat relationships at more than one scale.Department of Biology
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Peterson, James T. "The evaluation of a hydraulic unit-based habitat system /." free to MU campus, to others for purchase, 1996. http://wwwlib.umi.com/cr/mo/fullcit?p9821340.
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Ciannelli, Lorenzo. "Cross-scale analysis of the Pribilof Archipelago, southeast Bering Sea, with a focus on age-0 walleye pollock (Theragra chalcogramma) /." Thesis, Connect to this title online; UW restricted, 2002. http://hdl.handle.net/1773/5292.
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Reidy, Christopher R. "The composition, structure, and distribution of the plant communities of Wilbur Wright Fish and Wildlife Area." Virtual Press, 2002. http://liblink.bsu.edu/uhtbin/catkey/1237766.
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The purpose of this study was to describe the composition, structure and spatial distribution of plant communities at Wilbur Wright Fish and Wildlife Area (WWFWA) in order to provide baseline information to which future conditions can be compared. The plant communities of WWFWA were delineated, sampled, and subsequently classified using the framework of the National Vegetation Classification System. Data were collected for three strata of vegetation: overstory, understory and groundcover. Five permanent plots were established in the forested communities to monitor changes in vegetation over time.Eleven general habitat types were described for WWFWA. Plant communities varied from highly diverse mature woods to successional communities dominated by exotic vegetation. The composition and structure of plant communities appears to be closely related to previous land-use. Management practices are recommended in order to improve the condition of depauperate plant communities and to maintain the integrity of native plant communities.Department of Biology
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Moore, Cordelia Holly. "Defining and predicting species-environment relationships : understanding the spatial ecology of demersal fish communities." University of Western Australia. Faculty of Natural and Agricultural Sciences, 2009. http://theses.library.uwa.edu.au/adt-WU2010.0002.
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[Truncated abstract] The aim of this research was to define key species-environment relationships to better understand the spatial ecology of demersal fish. To help understand these relationships a combination of multivariate analyses, landscape analysis and species distribution models were employed. Of particular interest was to establish the scale at which these species respond to their environment. With recent high resolution surveying and mapping of the benthos in five of Victoria's Marine National Parks (MNPs), full coverage bathymetry, terrain data and accurate predicted benthic habitat maps were available for each of these parks. This information proved invaluable to this research, providing detailed (1:25,000) benthic environmental data, which facilitated the development and implementation of a very targeted and robust sampling strategy for the demersal fish at Cape Howe MNP. The sampling strategy was designed to provide good spatial coverage of the park and to represent the park's dominant substrate types and benthic communities, whilst also satisfying the assumptions of the statistical and spatial analyses applied. The fish assemblage data was collected using baited remote underwater stereo-video systems (stereo- BRUVS), with a total of 237 one-hour drops collected. Analysis of the video footage identified 77 species belonging to 40 families with a total of 14,449 individual fish recorded. ... This research revealed that the statistical modelling techniques employed provided an accurate means for predicting species distributions. These predicted distributions will allow for more effective management of these species by providing a robust and spatially explicit map of their current distribution enabling the identification and prediction of future changes in these species distributions. This research demonstrated the importance of the benthic environment on the spatial distribution of demersal fish. The results revealed that different species responded to different scales of investigation and that all scales must be ix considered to establish the factors fish are responding to and the strength and nature of this response. Having individual, continuous and spatially explicit environmental measures provided a significant advantage over traditional measures that group environmental and biological factors into 'habitat type'. It enabled better identification of individual factors, or correlates, driving the distribution of demersal fish. The environmental and biological measures were found to be of ecological relevance to the species and the scale of investigation and offered a more informative description of the distributions of the species examined. The use of species distribution modelling provided a robust means for the characterisation of the nature and strength of these relationships. In addition, it enabled species distributions to be predicted accurately across unsampled locations. Outcomes of the project include a greater understanding of how the benthic environment influences the distribution of demersal fish and demonstrates a suite of robust and useful marine species distribution tools that may be used by researcher and managers to understand, monitor, manage and predict marine species distributions.
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Eklöv, Peter. "Effects of behavioural flexibility and habitat complexity on predator-prey interactions in fish communities." Doctoral thesis, Umeå universitet, Ekologi och geovetenskap, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-101769.
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Coles, David P. "Dusk transition in sub-tropical reef fish communities off of North and South Carolina." Thesis, College of Charleston, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1565212.
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Although dawn and dusk periods comprise a relatively small part of the day, their importance as key ecological transition periods has been recognized for some time. Previous marine investigations into this transition have focused on tropical locations and have mostly been qualitative in nature. This project focused on the dusk period in sub-tropical reef fish communities off the coasts of North and South Carolina. High-definition underwater video was collected in 2013 and 2014 at a variety of sites featuring natural live-bottom habitat. Independent samples (43 videos) were obtained on 17 sampling dates. Fishes were tallied by time relative to sunset (TRTS) in an effort to identify temporal abundance patterns and categorize taxa by temporal niche. Sufficient data were collected for statistical analysis of 27 taxa, representing 15 families. Analyses explored whether there was a relationship between time and abundance. Of the taxa analyzed, ten showed no temporal pattern during the dusk period, seven showed abundance peaks during dusk, and ten showed declines in abundance during dusk. Patterns were not always consistent within families. In particular, the Serranidae and Sparidae families featured a variety of patterns. Uncommon species and ephemeral behavioral events were also noted and described.