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Zeidler, Wolfgang. "Systematic studies of pelagic hyperiidean amphipods of the infraorder Physocephalata (Crustacea: Amphipoda: Hyperiidea) /". Title page, contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phz43.pdf.
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Powell, Roger. "Ovigerous amphipods as 'freight hauliers'". Thesis, University of London, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311851.
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Brooks, Steven John. "The osmoregulation of selected gammarid amphipods". Thesis, Nottingham Trent University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272439.
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Wilkinson, Toby. "Diversity of microsporidia infecting gammarid amphipods". Thesis, Aberystwyth University, 2010. http://hdl.handle.net/2160/128ade99-3a3b-4ebf-bef9-f46a2936d384.
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Macdonald, Kenneth S. "Molecular Phylogeny of Lake Baikal Amphipods". W&M ScholarWorks, 1999. https://scholarworks.wm.edu/etd/1539617748.
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Morritt, D. "The ecophysiology of selected talitroidean amphipods (Crustacea:Amphipoda:Talitroidea)". Thesis, University of Bristol, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233861.
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Sweatman, Jennifer L. "Gammaridean Amphipods as Bioindicators in Subtropical Seagrass Ecosystems". FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2603.
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Anthropogenic disturbances are ubiquitous in coastal marine ecosystems. As such, more intensive monitoring efforts are necessary to conserve these valuable habitats. Bioindicators, organisms that predictably respond to changes in environmental variables, may be utilized in monitoring efforts to assess ecosystem functioning. To incorporate organisms into monitoring programs as bioindicators managers need to first understand the difference between the natural phenology of the focal organisms and their responses to different forms of anthropogenic disturbance.
To determine if gammaridean amphipods could be used as indicators of changes in environmental quality in sub-tropical seagrass ecosystems, I conducted spatial and temporal surveys of amphipod communities in south Florida. Amphipod community structure varied significantly across sites and seasons. Variation in community structure was largely driven by macrophyte biomass, food availability, seasonally variable factors (epiphyte abundance, dissolved oxygen, salinity, and temperature), water-column nitrogen concentration, and factors related to freshwater input, including low Thalassia testudinum and high Halodule wrightii densities, and salinity.
Amphipods are also susceptible to mechanical damage in seagrass habitats and could be used as indicators of ecological functioning of a region. A major source of mechanical damage in seagrass ecosystems is caused by boat propellers. I simulated propeller scars in continuous seagrass beds to investigate the effects of scarring on seagrass ecosystem functioning. Seagrasses located adjacent to propeller scars experienced a shift in the limiting resource from light to phosphorus. Amphipod community structure, however, was not impacted by scarring, but amphipod density was reduced in fragmented patches. To determine if plant-herbivore interactions were impacted by propeller scarring, we removed amphipods from half of the experimental plots and measured epiphyte biomass and community composition. Top-down control on epiphyte biomass or community composition by amphipods was not affected by fragmentation, despite reduced amphipod densities.
My dissertation research demonstrates that amphipods could be incorporated into existing management programs in sub-tropical seagrass ecosystems as environmental indicators. Reduced amphipod densities in fragmented seagrass beds suggests that amphipods could also be used as ecological indicators, but more research is needed to determine the extent of the impacts of fragmentation on higher trophic levels.
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Premke, Katrin. "Aggregations of Arctic deep-sea scavenging amphipods at large food falls = Ökologische Untersuchungen nekrophager Amphipoden in der arktischen Tiefsee /". Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 2006. http://www.loc.gov/catdir/toc/fy0706/2006506722.html.
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Andringa, Stephanie Lynn. "Ecology, Population Dynamics, and Sexual Characteristics of Commensal Leucothoid Amphipods with the Sponge Cliona varians in the Florida Keys (Crustacea: Amphipoda)". NSUWorks, 2015. http://nsuworks.nova.edu/occ_stuetd/28.
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Recent observations have identified a new species of leucothoid amphipod, Leucothoe “sp. F,” associated with the sponge Cliona varians. This project examined the relationship between this amphipod and its sponge host at three sites in the Florida Keys with differing hydrodynamic regimes. Ninety-eight sponge samples with a total of 2,030 amphipods were collected between December 2011 and September 2012. Leucothoe “sp. F” is currently a common species in the Florida Keys strongly associated with C. varians; its distribution strongly coincides with open tidal currents from the Gulf of Mexico. Seasonality, depth, and tidal regimes not only influence population dynamics and sexual characteristics of Leucothoe “sp. F,” but also the abundance and volume of its host.
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Rastrick, Samuel Paul. "Latitudinal variations in the energy consumption of gammarid amphipods". Thesis, Bangor University, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510277.
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Hume, K. D. "Sexual selection, pairing patterns and parasitism in freshwater amphipods". Thesis, Queen's University Belfast, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268447.
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Crichton, Rosemary. "Physiological capacities of gammarid amphipods to survive environmental change". Thesis, Bangor University, 2014. https://research.bangor.ac.uk/portal/en/theses/physiological-capacities-of-gammarid-amphipods-to-survive-environmental-change(717bfe8a-5d4f-4ce5-92f1-eda61134049e).html.
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Kennedy, Fergus. "The locomotor behaviour of peracarid crustaceans on wave-exposed sandy beaches of Chile". Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263174.
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Vonk, Ronald. "Explorations of the systematics and deep history of stygobiont amphipods". [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/68555.
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Kelly, D. W. "The role of native and invasive amphipods (Crustacea) in freshwater communities". Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390875.
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Agnew, D. J. "The comparative physiology of two species of intertidal gammaridean amphipod". Thesis, University of Glasgow, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374515.
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Siqueira, Silvana Gomes Leite 1975. "Alga parda Sargassum furcatum e anfípodes ampitóides associados com potenciais bioindicadores de poluição por hidrocarbonetos de petróleo". [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315929.
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Orientadores: Fosca Pedini Pereira Leite, Giuliano Buzá JacobucciTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-21T12:16:02Z (GMT). No. of bitstreams: 1 Siqueira_SilvanaGomesLeite_D.pdf: 2460624 bytes, checksum: 11cc560773d9117ec50e5c04d3f4ba0c (MD5) Previous issue date: 2012
Resumo: O monitoramento dos ambientes marinhos pode ser feito avaliando a presença de poluentes em organismos que são capazes de acumular estas substâncias. Desta forma, este estudo avaliou a presença de hidrocarbonetos petrogênicos na alga parda Sargassum furcatum e em anfípodes ampitoídeos associados provenientes de costões rochosos do Canal de São Sebastião, o qual está sujeito à poluição por petróleo, devido às operações do Duto e Terminais Centro Sul (DTCS) e por efluentes domésticos. Identificou-se as espécies de ampitoídeos que ocorreram associadas ao S. furcatum estudando também a variação espacial e temporal da composição desta comunidade. A relação entre os hidrocarbonetos presentes em S. furcatum, a densidade e a estrutura populacional de Cymadusa filosa, espécie de ampitoídeo mais representativa da região, também foi investigada. Adicionalmente foi realizado o estudo do comportamento reprodutivo de C. filosa e avaliado o seu uso como bioindicador de qualidade da água, por meio de teste de toxidade aguda de curta duração. O material analisado foi proveniente de 7 coletas realizadas entre março de 2007 a novembro de 2008 em 7 costões rochosos. Foram quantificados os hidrocarbonetos alifáticos e policíclicos aromáticos derivados de petróleo tanto na alga como nos anfípodes, que compostos variaram em termos de concentração entre os meses amostrados. A alga possivelmente refletiu as concentrações de hidrocarbonetos presentes na água enquanto que os anfípodes podem ter assimilado via contato direto ou via alimentação. Foram identificadas seis espécies de anfípodes da Família Ampithoidae: Ampithoe sp., A. divisura, A. marcuzzi, A. ramondi, C. filosa e Sunampithoe pelagica que apresentaram diferenças significativas em termos de ocorrência, densidades e variação temporal. A população de C. filosa, de modo geral, foi dominada por jovens, possivelmente devido a elevada fecundidade das fêmeas. Ocorreu também desvio da razão sexual a favor das fêmeas, relacionado com o comportamento diferencial do macho ou devido a sua maior sensibilidade aos hidrocarbonetos presentes na alga. Tanto hidrocarbonetos alifáticos como policíclicos aromáticos influenciaram a densidade e estrutura de tamanho dos diferentes estádios de desenvolvimento de C. filosa. Foram observadas interações agonísticas entre machos e fêmeas de C.filosa, formação de tubos conjugais e a alimentação de filhotes ainda no marsúpio pela fêmea, caracterizando o cuidado parental desta espécie. Verificou-se ainda que o período de incubação dos ovos foi curto e a maturidade sexual ocorreu entre seis a sete semanas. Os resultados de toxidade aguda sugerem que C.filosa tem um potencial para uso em experimentos de ecotoxicologia marinha devido a elevada sensibilidade ao cobre e ao naftaleno, contudo estudos adicionais com outros xenobióticos são necessários para comprovação destes resultados e para validar o uso desta espécie no monitoramento dos ambientes marinhos
Abstract: The monitoring of marine environments can be made by evaluation of pollutant presence in organisms that are able to accumulate these substances. Thus, this study evaluated the occurrence of oil-derived hydrocarbons in the brown algae Sargassum furcatum and in its associated amphitoid amphipods found on rocky shores of the São Sebastião Channel, which is exposed to pollution by oil due to the operations of the Duct and Center Southern Terminal (DTCS) and domestic sewage. The species of amphitoid that occurred associated to S. furcatum were identified, and time and spatial variation of the composition of this community were also studied. The relationship between the hydrocarbons present in S. furcatum and the density and populational stucture of Cymadusa filosa, the most representative species of amphitoid in the area, was also investigated. Additionally a study on the reproductive behavior of C. filosa was conducted and its use as a bioindicator of water quality was evaluated through high toxicity test of short duration. The analysed material was obtained from 7 samples taken from march 2007 to november 2008 on 7 rocky shores. The oil-derived aliphatic and polycyclic aromatic hydrocarbons were quantified both in the algae and in the amphipods. Such compounds varied in concentration between the months of sampling. The algae possibly reflected the hydrocarbon concentrations present in the water while the amphipods may have assimilated hydrocarbons by direct contact or through the trophic chain. Six species of amphipods from the Ampithoidae family were identified: Ampithoe sp., A. divisura, A. marcuzzi, A. ramondi, C. filosa and Sunampithoe pelagica which presented significant differences in occurrence, density and temporal variation. The population of C. filosa in general was dominated by young individuals, possibly due to the high fecundity of the females, and there was a deviation of the sexual ratio favoring the females, related to the male?s differential behavior or due to its higher sensibility to hydrocarbons in the algae. Both aliphatic and polycyclic aromatic hydrocarbons influenced the density and size structure of the different stages of development of C. filosa. Agonistic interactions between male and female C. filosa were observed, formation of share tubes and feeding of the offspring still in the pouch by the female, characterizing parental care by this species. It was also verified that the egg incubation period was short and sexual maturity occurred between six and seven weeks. The results of high toxicity suggest that C. filosa has potential for use in experiments of marine ecotoxicology due to its high sensibility to copper and naphthalene, however, additional studies with other xenonbiotics are necessary to confirm these results and to validate the use of this species in marine environments monitoring
Doutorado
Ecologia
Doutora em Ecologia
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Quiles, Adrien. "Evolutionary histories of symbioses between microsporidia and their amphipod hosts : contribution of studying two hosts over their geographic ranges". Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCK094.
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Titre: Histoire évolutive des symbioses entre les microsporidies et leurs hôtes amphipodes: contribution de l’étude de deux hôtes sur leurs aires de repartion géographiques.Mots clés: Symbioses, phylogénie, phylogéographie, amphipodes, hôte parasite, microsporidies.Résumé: Les microsporidies sont des endoparasites obligatoires, ils utilisent deux modes de transmission pour expoiter leurs hotes. Certaines espèces utilisent la transmission verticale et d'autres la transmission horizontale. La première favorise la co-spéciation et la spécificité hôte-parasite, tandis que la seconde favorise les échanges de parasites entre espèces hôtes. Les amphipodes d'eau douce sont des hôtes privilégiers pour de nombreuses espèces de microsporidies, mais aucun schéma général de spécificité hôte-parasite ou de co-diversification n’émerge des recherches menées depuis trente ans.Dans ce travail, la diversité des infections microsporidiennes, sur la base des données SSU rdNA, ont été évaluées dans deux complexes d'espèces de Gammarus, G. roeselii et G. balcanicus, sur l'ensemble de leur aire de répartition géographique, en s'appuyant sur des efforts d'échantillonnage importants (environ 100 sites et 2 000 individus). L’objectif de ce doctorat est (i) d’explorer la diversité microsporidienne présente dans les deux hôtes et leurs relations phylogénétiques; (ii) vérifier si la phylogéographiques de l'hôte peut expliqué l'association hôte-parasite (co-diversifications ou récents aquisition a partir de la faune locale); (iii) proposer des scénarios d'histoire évolutive hôte-parasite pour expliquer la diversité et le schéma co-bio-géographique observé chez les deux espèces hôtes chez N. granulosis.Le marqueur SSU d’ADNr a révélé un grand nombre de variants chez ces deux hôtes (c’est-à-dire 24 et 54 haplogroupes de, respectivement), regroupés en 18 taxons d’espèces, presque tous partagés entre les deux espèces hôtes. De nombreux haplogroupes de microsporidia appartenant à une espèce parasite donnée sont spécifiques à l'hôte, ce qui suggère un certain niveau de codiversification à cette échelle. Au sein de chacun des complexes d'espèces hôtes, la confrontation des phylogéographies des hôtes et des parasites suggère également un certain degré de co-diversification. Ceci reste néanmoins à confirmer, principalement parce que l'ADNr SSU atteint ses limites en termes d'informations phylogénétiques à cette échelle plus fine.Il est frappant de constater que presque tous ces taxons de microsporidia mis en évidence dans ce travail avaient déjà été détectés chez d’autres gammaridés. Certains étaient déjà des taxons parasites clairement identifiés associés aux amphipodes: Nosema granulosis, Dictyocoela roeselum, D. muelleri, D. roeselum, D. duebenum, D. berillonum, Cucumispora roeselum, C. ornata, Microsporidium sp 515 et Microsporidium sp 505). Mes résultats ont élargis les spectres taxonomiques d’hôte et les répartitions géographiques de ces parasites (souvent très étendues). Certains autres taxons étaient connus pour être extrêmement rares, et ne sont pas complètement décrits. Mon travail de doctorat a également étendu le spectre taxonomique d’hôte et / ou élargi considérablement les aires géographiques de ces taxons. Cela permet une réévaluation de ces taxons, faisant passer leur statut d'associations anecdotiques à des associations potentiellement bien établies, mais jusque là négligées, chez les amphipodesTitle: Evolutionary histories of symbioses between microsporidia and their amphipod hosts : contribution of studying two hosts over their geographic ranges.Keywords: Symbioses, Phylogeny, Phylogeography, Amphipods, Host-Parasite, MicrosporidiaAbstract: Microsporidia are obligate endoparasites, exploiting their hosts with either vertical or horizontal transmission. While the former may promote co-speciation and host-specificity, the latter may promote shifts between host species. Freshwater amphipods are hosts for many microsporidian species, but no general pattern of host specificity and co-diversification is known.In my PhD work microsporidian infections, identified with SSU rDNA, were assessed in two Gammarus species complexes, G. roeselii and G. balcanicus , over their full geographic ranges (each c. 100 sites and 2000 individuals) in aim of (i) exploring the microsporidian diversity present in both hosts and their phylogenetic relationships; (ii) testing if the host phylogeographic history might have impacted host-parasite association (co-diversifications or recent host-shifts from local fauna); (iii) proposing the host-parasite evolutionary history scenarios to explain the diversity and co-bio-geographical pattern observed in the two host species between using N. granulosis as a model.The SSU rDNA marker revealed a high number of microsporidian variants (i.e. haplogroups, 24 and 54, respectively), clustered into 18 species-level taxa, almost all being shared between the two host species. However, many microsporidian haplogroups within a given parasite species are host-specific, suggesting host-parasite co-variation. Within each host species-complex, while the confrontation between hosts and parasites phylogeography suggested some degrees of co-diversification, these patterns remain to be confirmed, mainly as SSU rDNA reached its limits in phylogenetic information content in that matter.Strikingly, almost all of these microsporidia taxa were previously detected in other gammarids, mainly within the genus Gammarus, but also in other genera of Gammaridae. Some were already clearly recognised parasite taxa associated with amphipods: Nosema granulosis, Dictyocoela roeselum, D. muelleri, D. roeselum, D. duebenum, D. berillonum, Cucumispora roeselum, C. ornata, C. dikerogammari, Microsporidium sp 515 and Microsporidium sp 505). Many times, my results increased host taxonomic spectrums and extended geographic ranges (often widely). Some other taxa were known to be extremely rare, having scarce literature records often with few or even very few geographic records and being not fully described. My PhD work either extend host taxonomic spectrum and/or deeply extend geographic ranges for these taxa. It allowed a reappraisal for such taxa, changing their status from puzzling anecdotic association to potentially overlooked established associations for amphipods
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Lacey, Nichola. "The ecology and physiology of trench amphipods from bathyal to hadal depths". Thesis, University of Aberdeen, 2015. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=230045.
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Hadal trenches account for the deepest 45% of the ocean (6000 - ~11,000 m). This environment is characterised by perpetual darkness, low temperature and high hydrostatic pressure. Amphipods dominate the scavenging fauna at these depths and are an ideal model organism with which to study this ecosystem. This thesis utilises an unprecedented data set, covering a bathymetric range of over 8000 m and across multiple hadal trench regions. I present both the first attempts at statistically robust ecological analyses of a hadal community and the first extensive examination of the biology and ecology of comparable fauna across multiple trenches. The distinction between “abyssal” and “hadal” communities varies between trenches. I posit that hydrostatic pressure and nutrient flux are primary drivers of community structure. While there is likely a boundary between the abyssal and hadal zones that is fundamentally set by a fauna's physiological limitations, there are also expected to be fauna that are specifically adapted to the environmental conditions (beyond pressure) of trenches. Within the hadal zone, food availability and associated competitive pressures appear to be primary drivers of population structure. Hadal amphipods accumulate extremely large (energy) triacylglycerol lipid reserves. These lipids are highly unsaturated, presumably to maintain metabolic accessibility under the solidifying effects of high hydrostatic pressure and low temperature. Species incorporate high proportions of 18:1(n-9) into their storage lipids, suggesting particular physiological importance. The membrane lipids of two hadal species are highly unsaturated, which I suggest is an adaptive mechanism to mitigate the harmful physiological effects of high hydrostatic pressure and low temperature. I find no evidence of differing physiological tolerance to pressure that would account for the zonation of the species. Rather, each species is understood to be specifically adapted to utilise the varying resources of the upper and lower hadal trench slope respectively.
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Allen, James Hamilton. "The analysis and prediction of the shallow subtidal benthic communities along the East Coast of England". Thesis, University of Hull, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327288.
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Chadwick, S. R. "Seasonal activity patterns and general biology of Talitrus saltator and Talorchestia deshayesii". Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370839.
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MacNeil, Calum. "The ecology of freshwater amphipods : a study of invasive and native species". Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312638.
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Blankenship, Lesley Elizabeth. "Ecology of the Tonga and Kermadec Trench hadal zone : inferences from scavenging amphipods /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3208810.
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Crowe, Stacie E. "Abundance and Distribution of Commensal Amphipods From Common Marine Sponges of Southeast Florida". NSUWorks, 2001. http://nsuworks.nova.edu/occ_stuetd/306.
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Marine sponges were examined from shallow waters of southeast Florida and the Florida Keys to determine species composition and distribution of commensal amphipod crustaceans from shallow reef, mangrove, and seagrass habitats. Twenty sponge species were investigated during this study, sixteen of which housed amphipods in the families Colomastigidae and/or Leucothoidae. Six species of commensal amphipods were identified. Leucothoe spinicarpa (Abildgaard) species "complex" was the most dominant amphipod commensal, representing 63% of the total amphipods collected. The L. spinicarpa "complex" contains four local morphotypes, which are diagnosed and briefly described. Common sponge hosts included Callyspongia vaginalis, Mycale sp., and Myriastra kallitetilla.
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Chavanich, Suchana. "Rocky intertidal zonation and habitat ecology of gammaridean Amphipods in Long Island Sound /". Click for abstract, 1997. http://library.ctstateu.edu/ccsu%5Ftheses/1484.html.
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Thesis (M.A.)--Central Connecticut State University, 1997.Thesis advisor: Dr. Kim A. Wilson. " ... in partial fulfillment of the requirements for the degree of Master of Arts in Biology." Includes bibliographical references (leaves 47-56).
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Miller, Patricia Anne. "The role of habitat heterogeneity in the community dynamics of an eelgrass-associated assemblage of gammarid amphipods". Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/24866.
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The role of density of eelgrass shoots in regulating distribution and abundance of gammarid amphipods was investigated. Monthly collections of amphipods were made over a one-year period in a series of treatment plots on Roberts Bank, in southwestern B.C., in which eelgrass (Zostera marina L.) shoots had been thinned to different relative densities. This experiment was originally designed to test the hypothesis that the abundance and diversity of amphipods would be positively related to the density of eelgrass shoots. Due to the rapid recovery of original shoot densities within the plots, however, this hypothesis could not be tested. Consequently, the emphasis of the study was restricted to a consideration of the effect of the disturbance created during removal of shoots on the distribution of amphipods. Collections of amphipods were also made in three areas of different natural densities of Zostera shoots during a three-month period in summer 1984, to assess further the effect of shoot density on the distribution and abundance of amphipods. The role of additional components of habitat heterogeneity, including drift algae and a second species of seagrass, Zostera japonica, in modifying the community dynamics of the amphipods was also studied. No relationship between the density of Zostera shoots and the abundance and diversity of amphipods was found. The amphipod community was dominated by Corophium acherusicum and the distribution of this species, as well as that of the other most frequently collected species, appeared to be regulated by the seasonality of macrophyte biomass. Peak abundances of amphipods occurred in the late summer and autumn when large amounts of drift algae and eelgrass detritus were present at the sediment surface. This decaying plant material is an important source of food for detritivores such as gammarids and its seasonal abundance was reflected in the rapid growth of populations of amphipods. The floating mats of drift algae, such as Ulva sp., also contributed significantly to the carrying capacity of the eelgrass meadow by providing spatial refuges to amphipods which are targets of fish and bird predation. The role of habitat heteogeneity in determining the distribution of the dominant species of amphipods, with reference to competition and predation, was discussed.Science, Faculty of
Zoology, Department of
Graduate
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Hall, Joseph D. "Ecology, Distribution, and Systematics of Leucothoid Amphipods of the West Florida Shelf Benthic Ecosystem". NSUWorks, 2008. http://nsuworks.nova.edu/occ_stuetd/253.
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This work examined the leucothoid amphipods collected during the Hourglass cruises (R/V Hernan Cortez 1965 – 1967) across the West Florida Shelf (Joyce et al., 1969), focusing on species identification and distributional patterns. Five of the six species identified were known from Caribbean and eastern Atlantic waters. This collection expands the known range of all five species to the Gulf of Mexico. The sixth species, Leucothoe L, is diagnosed as new. Although 16 stations were sampled, data was analyzed statistically only from the 10 stations where leucothoids were found, (stas. A-E and I-M). A SIMPROF dendogram generated from relative abundance data identified three groups of stations with similar community composition (Group 1 - I, A, J at the 100% level; Group 2 - D, C, L at the 83% level, and Group 3 - E, M, B, K at the 87% level). A SIMPER analysis revealed that L. kensleyi was the most statistically influential species in community composition when comparing groups 1 versus 2 and 1 versus 3, while L. ashelyae, L. barana, L. kensleyi, and L. urospinosa contributed equally to the difference seen between groups 2 and 3.
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Thompson, Audrey Marie. "AMPHIPODS ARE STRONG INTERACTORS IN THE FOOD WEB OF A BROWN-WATER SALMON RIVER". The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-05092007-145457/.
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Marine derived biomass from salmon carcasses is incorporated into coastal Pacific Rim salmon river systems via the organisms and structures of the freshwater foodweb. In brown water rivers of Western Kamchatka, the foodweb is dominated by ubiquitous benthic amphipods (Anisogammarus kygi) that consume salmon carcass material. We hypothesized that A. kygi are a strong interactor in the feedback loop which links dead spawner biomass to juvenile salmonid growth. We found that A. kygi had a complex life cycle with anadromous and resident forms. A. kygi dominated the macro-benthos, comprising more than 88.0% (SE=.01, N=7) of invertebrate biomass, and were highly mobile within the system, exhibiting upstream migrations of ovigerous females (23 ind/m3 ± 5), drift of juveniles, and re-distribution during carcass loading. A. kygi was observed feeding on 97% of salmon carcasses examined (N=100), making up 98.8% (SE .007) of invertebrate consumers, at densities up to 3,000 carcass-1. Amphipods were an important food item for rearing salmonids, especially during the summer when fish diets reached a peak of 88.7% (SE=6.0%) amphipods in 2005, and 68% (SE=18%) amphipods in 2006. The condition factor of salmonid juveniles (K) increased from spring to summer, particularly in juvenile chum, whose spring diet was 76.83% (SE 0.05) amphipods, corroborating the importance of an amphipod based diet for salmonids in this river. We concluded that A .kygi is a strong interactor in the Utkholok system. We also observed abundance of A. kygi in six other brown water rivers of western Kamchatka which suggests that the amphipod-mediated feedback of marine derived nutrients described for the Utkholok, is typical of brown water systems with salmon.
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Thompson, Audrey Marie. "Amphipods are a strong interactor in the foodweb of a brown-water salmon river". CONNECT TO THIS TITLE ONLINE, 2007. http://etd.lib.umt.edu/theses/available/etd-05092007-145457/.
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Fernandez-Gonzalez, Victoria. "Fouling amphipods on marine aquaculture facilities: ecological interactions and potential applications and potential applications". Doctoral thesis, Universidad de Alicante, 2017. http://hdl.handle.net/10045/89091.
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Aquaculture facilities involve mooring a large amount of artificial structures in offshore areas, which are colonised by a wide group of marine organisms, forming characteristic fouling communities. Many studies have focused on determining what sessile organisms are able to settle on nets, ropes and buoys, owing to the specific problems they cause and their economic cost to the aquaculture industry. Although sessile fouling communities are well-studied from the point of view of controlling this community on aquaculture facilities, little is known about the epifaunal mobile species inhabiting these artificial structures. This thesis addresses the study of crustacean amphipods, which have been scarcely studied regarding their species composition and relation to the habitats created by the sessile species and despite being detected in high abundances. After the general introduction, which sets the study framework, Chapter 1 is a preliminary study on the composition of fouling assemblages on aquaculture facilities in the Mediterranean Sea, comparing them with others such as those in harbours or offshore structures. Therein, it is shown that fouling communities are made up of mainly bivalves, algae, hydroids and bryozoans and amphipods usually represent more than 80 % of motile fauna associated with these organisms. Moreover, amphipod assemblages are characterised by seven frequent and dominant species: Elasmopus rapax, Jassa marmorata, Jassa slatteryi, Ericthonius punctatus, Stenothoe tergestina, Caprella equilibra and Caprella dilatata. A quantitative study of amphipod densities is carried out in Chapter 2, where mean amphipod densities observed in fish farm fouling amounted to 176,000 ind.m-2 and reached maxima up to 1,000,000 ind.m-2. There, the role of the macro- and microhabitat in supporting such amphipod communities is explored. The effect of the modification of marine currents on pelagic communities due to the introduction of coastal infrastructures is analysed in Chapter 3. Therein, it was detected a retention effect on planktonic amphipods near such facilities, noticeable in the increased abundance of hyperiids and migrating amphipods from different benthic and floating habitats. The influence of fouling amphipods on other habitats is analysed in Chapters 4 and 5, it is shown that fish-farm fouling acts as a source population of amphipods dispersing towards both defaunated sediments in soft-bottoms and surrounding floating habitats. Finally, in the last chapter, based on the possibility of using wild fauna already growing in fish farms, the applicability of amphipods as an accessory culture is tested in an offshore integrated multi-trophic aquaculture (IMTA) system with finfish as main fed species. Throughout this thesis it has been shown that fish-farming activities affect the amphipod assemblage in several ways such as the establishment of high population densities or the intimate connectivity between different subpopulations. As a result, a new potential commercial application arises from the possibility of using them as biofilters of aquaculture wastes, within an off-coast integrated multitrophic aquaculture system, promoting a more sustainable development of aquaculture in the marine environment.Las estructuras artificiales que conforman las instalaciones de acuicultura en mar abierto suelen ser colonizadas por multitud de organismos marinos, que forman comunidades de fouling características en estas estructuras. Muchos estudios se han centrado en la descripción de los organismos sésiles que se desarrollan sobre cabos, redes y boyas de las instalaciones de acuicultura, debido a los problemas que generan para el cultivo y los costes adicionales que significan para la industria derivados de su necesaria eliminación. Sin embargo, aunque las comunidades de fouling sésiles han sido bien estudiadas desde el punto de vista de su control en las instalaciones de acuicultura, poco se sabe sobre la epifauna que habita estas estructuras artificiales. Esta tesis se centra en el estudio de los crustáceos anfípodos, los cuales aún no han sido estudiados en cuanto a la composición de especies y a su relación con los hábitats creados por los organismos sésiles, a pesar de haber sido detectados en grandes abundancias en las instalaciones de acuicultura. Después de una introducción general, que establece el marco de estudio, el capítulo uno es un estudio preliminar sobre las comunidades de fouling de las instalaciones de acuicultura en el Mediterráneo, comparándolas con las desarrolladas en otras estructuras artificiales como puertos o plataformas petrolíferas. En este capítulo, se demuestra que las comunidades de fouling están compuestas principalmente por bivalvos, algas, hidrozoos y briozoos y que más de un 80% de la fauna asociada a estos organismos son anfípodos. Además el poblamiento se caracteriza por la presencia de siete especies de anfípodos que son frecuentes y abundantes: Elasmopus rapax, Jassa marmorata, Jassa slatteryi, Ericthonius punctatus, Stenothoe tergestina, Caprella equilibra y Caprella dilatata. Un estudio cuantitativo de las densidades de estos anfípodos se lleva a cabo en el capítulo 2, donde se encuentra que la densidad media es de 176.000 ind.m-2, con máximos de más de 1.000.000 ind.m-2. Allí se explora también el papel de los macro y microhábitats en mantener dichas poblaciones de anfípodos. El efecto de la modificación de corrientes sobre las comunidades plantónicas debida a la instalación de las piscifactorías se analiza en el capítulo 3. En él, se detectó una retención de los anfípodos planctónicos cerca de las instalaciones, evidenciada por el incremento en las abundancias de hipéridos y de anfípodos migradores desde diferentes hábitats bentónicos flotantes. La influencia de las grandes densidades de anfípodos del fouling sobre otros hábitats se estudia en los capítulos 4 y 5, donde se observó que el fouling actúa como fuente de anfípodos migradores, exportando individuos que colonizan tanto sedimentos defaunados en el fondo marino como otros hábitats flotantes cercanos. Finalmente, en el último capítulo se analiza la posibilidad de aprovechar la producción natural y la conectividad observadas a través del cultivo de anfípodos como parte de un sistema de acuicultura multitrófica integrada (AMTI) en mar abierto con peces como especie principal. A lo largo de esta tesis, se demuestra que la acuicultura influencia las poblaciones de anfípodos marinos, tanto en el establecimiento de grandes densidades de población como en la conectividad entre las diferentes subpoblaciones. Como resultado, surge una nueva aplicación comercial de la posibilidad de usar los anfípodos del fouling como biofiltros, reciclando los residuos de la acuicultura dentro de un sistema de acuicultura multitrófica, garantizando así un desarrollo más sostenible de la acuicultura en el medio marino.
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Chapman, Trevor. "Enemy Exacerbation: Effects of Predator Stress on Sulfate Lethality in Freshwater Amphipods (Gammarus minus)". Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etd/3297.
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Predator cues can influence how aquatic organisms respond to anthropogenic contaminants. This study examined the effects of predator cues on behavior, metabolic rate, and sulfate (as Na2SO4) toxicity in amphipods (Gammarus minus). Predator cues included alarm cue (macerated conspecifics) and kairomone from mosquitofish (Gambusia affinis). Amphipods decreased activity and increased time in refuge when exposed to alarm cue, and increased time in refuge when exposed to kairomone. While median lethal concentrations (96-h LC50) were not influenced by predator cues, analysis of dose response curves indicated that kairomone exposure increased amphipod sensitivity to mid-range concentrations of sulfate (500-1,000 mg/L). Amphipods increased oxygen consumption in response to kairomone but not alarm cue. The influence of predator cues on contaminant lethality can be dependent on the type of cue, and physiological endpoints such as metabolic rate may help explain the basis of observed interactions.
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Cornet, Stéphane. "Ecologie et évolution des défenses immunitaires au sein des interactions amphipodes - acanthocéphales immunodépresseurs". Dijon, 2009. http://www.theses.fr/2009DIJOS044.
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Le système immunitaire est une fonction importante pour contrôler les infections et limiter les effets négatifs des parasites sur la fitness des organismes. Malgré les bénéfices directs, l'immunité est coûteuse. Les trade-offs inhérents à la théorie des traits d'histoire de vie et l’environnement vont contraindre et moduler le maintien des défenses et l’expression de la réponse immunitaire et ainsi maintenir de la variabilité au niveau individuel et populationnel. Cette étude l’a mis en évidence pour la phénoloxydase (PO), une enzyme impliquée dans le processus de mélanisation chez les invertébrés. Le rôle majeur des parasites acanthocéphales sur la variabilité de l’immunité des gammares a reçu une attention particulière. Lors de leur développement, les acanthocéphales sont exposés à la réponse immunitaire de leurs hôtes intermédiaires. Afin d’éviter leur élimination, les parasites ont mis en place des mécanismes de contournement du système immunitaire. L’immunodépression, résultat d’une histoire coévolutive, est caractérisée par l’altération de l’activité PO et de la densité en hémocytes. La réduction de l’immunocompétence des hôtes parasités va exacerber la virulence du parasite, et ceci d’autant plus que le risque de contracter des infections opportunistes dans le milieu est important. Cependant, les parasites diffèrent dans leurs effets immunodépresseurs induits post-infection et l’amplitude de l’immuno-évasion covarie négativement avec la virulence, suggérant que, parmi les hôtes infectés et sous certaines conditions, l’immuno-modulation serait bénéfique en limitant les coûts d’auto-réactivitéThe immune system is essential to keep infection at bay and to limit the negative effects of parasites on host fitness. Although beneficial, the immunity is a costly function. The trade-offs inherent to the theory of life history traits and the environment will constrain and modulate the maintenance of defences and the expression of the immune response, hence maintaining a variation at the individual and population level. This was shown by this study for the phénoloxydase (PO), an enzyme involved in the melanization pathway in invertebrates. The major role of acanthocephalan parasites in the variability of immune defences in gammarids has received a particular attention. While developing within the intermediate host, acanthocephalans are exposed to the host immune response. To avoid clearance, parasites have developed strategies aiming at circumventing the host immune system. The immunodepression, resulting from a coevolutionary process, is characterised by the alteration of the PO activity and haemocyte density. The reduced immunocompetence of parasitized host leads to an increased parasite virulence, and especially when the risk to contract opportunistic infection in the environment is high. However, parasite differ in their induced immunodepressive effects and the magnitude of immune evasion negatively covaries with virulence, suggesting that, among infected hosts and under certain conditions, the modulation of the host immune system could be beneficial by limiting some costs of autoreactivity
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Van, Overdijk Colin D. A. "Microhabitat selection by the amphipods Echinogammarus ischnus and Gammarus fasciatus in laboratory and field experiments". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0033/MQ62296.pdf.
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Hesselschwerdt, John [Verfasser]. "Impacts of invasive amphipods on the local benthic fauna and leaf litter decomposition / John Hesselschwerdt". Konstanz : Bibliothek der Universität Konstanz, 2009. http://d-nb.info/1020366109/34.
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Carruthers, Erin Hana. "Habitat, population structure and energy value of benthic amphipods and implications for gray whale foraging in Clayoquot Sound, British Columbia". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0011/MQ52885.pdf.
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browne, Joanna. "Parasites of Jellyfish in Eastern Australia". Thesis, Griffith University, 2015. http://hdl.handle.net/10072/367791.
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Parasites are a major component of the Earth’s biota, yet are often overlooked and their importance underestimated. They affect nearly all organisms and can potentially regulate the populations of their hosts. Jellyfish are abundant members of the zooplankton community and are renowned for their ability to form large blooms. Jellyfish host a large diversity of parasites. Some of these parasites (e.g. hyperiid amphipods and parasitic anemones) use jellyfish as the sole host in their life cycle, whilst others (e.g. digenean trematodes and cestodes) use jellyfish as an intermediate host between other host organisms. There have been few ecological studies of jellyfish parasites (for example of spatial and temporal variation in parasite-host relationships) relative to other aspects of jellyfish biology. This may be partly attributable to the very small size of some parasites (e.g. digenean trematodes) and also to difficulties such as identifying larval parasite forms. However, with the advent of new technologies, such as molecular identification, and with diligent examination, these difficulties are able to be overcome. This thesis aims to identify jellyfish parasites using molecular and morphological techniques and elucidate their life cycles, examine spatial and temporal variation in jellyfish parasites and investigate the diversity and host specificity of the parasites of jellyfish in eastern Australia.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Shea, James Robert. "Salinity tolerance and osmoregulation of the Arctic marine amphipods Onisimus litoralis (KrÜyer) and Anonyx nugax (Phipps)". Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=64011.
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Qui, Yang. "The Distribution and Diversity of Parasites in the Ancient Species Flocks : Baikalian Amphipods & Microsporidian Parasites". Thesis, University of Leeds, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515386.
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Mills, Christopher Lloyd. "Some ecophysiological responses to osmoregulatory stress in selected aquatic amphipods with special reference to Gammarus duebeni". Thesis, University of Southampton, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278762.
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Postaski, Lindsey L. "Life History and Ecology of the Freshwater Amphipods Gammarus pseudolimnaeus and Gammarus fasciatus in Southeastern Virginia". W&M ScholarWorks, 2012. https://scholarworks.wm.edu/etd/1539626926.
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Klebba, Kristine N. "Systematics, Ecology, and Functional Morphology of Commensal Amphipods (Leucothoidae) in the Western Caribbean Sea and Southeast Florida". NSUWorks, 2005. http://nsuworks.nova.edu/occ_stuetd/250.
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Endocommensal leucothoid amphipods are ecologically important in marine ecosystems worldwide. However, our understanding of the evolution and taxonomy of the group is confused. Although leucothoids typically occupy specialized niches, Leucothoe spinicarpa, the type species for the genus Leucothoe, has been reported from a wide variety of habitats. This study compared the taxonomy, ecology, and functional morphology of Caribbean commensal amphipods previously attributed to L. spinicarpa and incorporated new host and ecological information and new diagnostic characters. As a result 11 new leucothoid species are described from Southeast Florida, the Florida Keys, and the Western Caribbean Sea.
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Palmer, Michelle Elaine. "Environmental factors affecting the relative abundance of native and invasive freshwater amphipods in the St. Lawrence River". Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81420.
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Freshwater ecosystems worldwide are being altered by multiple stressors. One of the most important stressors is biological invasion---the introduction of exotic species, which can contribute to the loss of native species. The effects of an introduced species are correlated with its abundance and typically vary across ecosystems, suggesting that its impact on native species is mediated by its environment, i.e. the physical habitat and the recipient community. However, there are few studies that explore the effects of environment on the interactions between exotic and native species. My thesis examines the influence of physical habitat variables and community interactions on the relative abundance of exotic and native freshwater crustaceans in the St. Lawrence River.The Eurasian amphipod Echinogammarus ischnus invaded the Great Lakes-St. Lawrence River system in the mid-1990s and has replaced the native North American Gammarus fasciatus as the dominant amphipod in littoral areas throughout Lake Erie and Lake Ontario.
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Kwapinska, Magdalena. "Taxonomic Review and Ultrastructural Analysis of the Commensal Amphipod genus Paraleucothoe (Crustacea: Amphipoda)". NSUWorks, 2009. http://nsuworks.nova.edu/occ_stuetd/233.
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A re-examination of the genera Leucothoe and Paraleucothoe through a literature review was performed. Specimens of a suspected invasive amphipod initially identified as Paraleucothoe flindersi collected from a host sponge Mycale sp. Gray, 1867, in Hawaiian coastal waters by D.G. Muir (Bishop Museum, Honolulu, Hawai’i) (Muir, 1997) were also examined for the purpose of their proper identification and to determine whether they are native or invasive to Hawai’i.
Published research suggests that, L. novaehollandiae Haswell, 1880, L. brevidigitata Miers, 1884, and P. flindersi (Stebbing, 1888) appear to be the same species, although their exact taxonomic placement remains uncertain. Careful reexamination revealed each to be distinct, all differing from the Hawaiian species examined here.
Detailed examination using both light and scanning electron microscopy and comparison with P. flindersi P. spinicarpus (Abildgaard, 1789), P. commensalis (Haswell, 1879 a), L. novaehollandiae, L. brevidigitata, and L. lihue Barnard, 1970, determined that the Hawaiian specimens represent a new undescribed species of Leucothoe.
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Appadoo, Chandani. "Some aspects of the biogeography and ecology of intertidal and shallow subtidal marine gammaridean amphipods of Mauritius (Indian Ocean)". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0001/MQ34159.pdf.
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Anteau, Michael J. "Ecology of lesser scaup and amphipods in the upper-Midwest scope and mechanisms of the spring condition hypothesis and implications for migration habitat conservation /". Connect to this title online, 2006. http://etd.lsu.edu/docs/available/etd-01242006-093828/.
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Ennis, Marilyn. "Parasite effects on the feeding behaviour and functional response of the invasive amphipod Gammarus pulex (Crustacea; Amphipoda)". Thesis, Queen's University Belfast, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705915.
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Parasites can structure communities and may impact on resource competitive interactions in novel communities. The amphipod Gammarus pulex is invasive in Ireland and in low land river stretches has displaced the native congener Gammarus duebeni celticus. Parasitism may facilitate invasion success by the more efficient use of resources. The functional response (the relationship between prey density and prey consumption) is a means of predicting the likely impact of an invader. In this thesis parasitism by two different acanthocephalan parasite species (Echinorhynchus truttae and Polymorphus minutus) elevated the functional response of G. pulex with either Baetis rhodani or Asellus aquaticus prey. Analysis of prey body part consumption in Baetis rhodani prey by E. truttae parasitised G. pulex revealed that parasitised predators consumed more prey material, partially consumed more prey but consumption distribution was not related to body part. In turn, partial prey consumption may reduce handling time in parasitised predators and may provide a mechanistic explanation for the elevation of functional response parameters. Unconsumed prey provide an additional food source for consumers that are too small or slow to capture larger prey, with consequences for nutrient cycling within freshwater communities. With regards to physiological parameters, non-starved parasitised and unparasitised G. pulex had similar haemolymph protein levels whereas starvation significantly elevated the haemolymph protein level of parasitised G. pulex compared to unparasitised animals. This finding suggested parasite upregulation of host protein resources to compensate for depletion of host haemolymph protein levels during starvation. Additionally, long term starvation did not affect survival rate in parasitised or unparasitised G. pulex but appeared to impact on parasite length in parasitised hosts.. Parasitised invasive predators such as G. pulex may therefore possess traits that allow more efficient use of resources compared to native congeners, which may facilitate and explain the invasion success of this species.
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Jakob, Lena Verfasser], Hans-Otto [Akademischer Betreuer] [Gutachter] [Pörtner i Rolf [Gutachter] Altenburger. "Thermal tolerance and cadmium susceptibility of amphipods endemic to Lake Baikal / Lena Jakob ; Gutachter: Hans-Otto Pörtner, Rolf Altenburger ; Betreuer: Hans-Otto Pörtner". Bremen : Staats- und Universitätsbibliothek Bremen, 2016. http://d-nb.info/1131768981/34.
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Coman, Francis Edmund, i n/a. "The Role of Epibenthic and Planktonic Fauna in Subtropical Prawn Grow Out Ponds". Griffith University. School of Environmental and Applied Science, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030926.091736.
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The assemblage composition, biomass and dynamics of zooplankton and epibenthos were examined in a commercial prawn pond in southeast Queensland over two seasons. Physico-chemical characteristics of the pond water were measured concurrently. Numbers and biomass of zooplankton in the surface tows (140 micrometre mesh) varied from 8 ind. L-1 (44 micrograms L-1) to 112 ind. L-1 (324 micrograms L-1) in the first season, with peaks in biomass corresponding to peaks in numbers. In the second season the zooplankton numbers varied from 12 to 590 ind. L-1, but peaks in numbers did not correspond with peaks in biomass, which varied from 28 to 465 micrograms L-1. This was due to differences in the size of the dominant taxa across the season. Although this occurred in both seasons, the effect on biomass was more pronounced in the second season. In both seasons, immediately after the ponds were stocked with prawn postlarvae there was a rapid decline in zooplankton numbers, particularly of the dominant larger copepods. This was probably due to predation by the postlarvae. Subsequent peaks in zooplankton numbers were principally due to barnacle nauplii. The largest peaks in zooplankton numbers occurred before stocking in the first season, but the largest peaks were in the middle of the second season. While changes in abundance and biomass of the zooplankton assemblage were not correlated with physico-chemical characteristics in the first season, there were correlations between zooplankton numbers and temperature, dissolved oxygen, pH and secchi disk readings in the second season. No correlations were found with zooplankton biomass and physico-chemical characteristics in the second season. The correlations in the second season were mainly due to the high prevalence of barnacle nauplii through the middle part of the season, and may reflect suitable conditions for barnacle reproduction. Epibenthic faunal abundance in the beam trawls (1 mm mesh) peaked at 14 ind. m-2 and 7 ind. m-2 in the first and second seasons respectively and the biomasses at 0.8 g m-2 and 0.7 g m-2. Peaks in abundance of epibenthos did not correspond to peaks in biomass. This was due to large differences in the size of the taxa across the seasons. Sergestids (Acetes sibogae) and amphipods were the most abundant taxa in beam trawl samples. Amphipods were only abundant in the first season, with their numbers increasing towards the end of the grow out period. Acetes were abundant in both seasons, but were dominant in the second season. Correlations between physico-chemical parameters and epibenthos numbers were found to be strongly influenced by the dominant taxa in each season. In the first season, negative correlations were found between epibenthos abundance and pH and temperature. These relationships may reflect an effect on the growth of macroalgae in the pond, with which the amphipods were strongly associated, rather than a direct effect on the epibenthos. In the second season, a positive correlation existed between temperature and epibenthos abundance, however this was strongly influenced by the very high abundance of Acetes in the last sampling period. No correlations were found between epibenthic fauna biomass and physico-chemical parameters. Abundances of epibenthic fauna were not related to zooplankton densities indicating this source of food was not likely to be a limiting factor. Neither the pond water exchange regime nor moon phase could explain changes observed in abundances of zooplankton or epibenthos assemblages in the first season, however the sampling regime was not designed to specifically investigate these effects. In the second season water exchanges were sampled more rigorously. The density of zooplankton in the outlet water was from 2 to 59% of the density of zooplankton in the pond, and the zooplankton density of the inlet water was from 9 to 50% of the outlet water. The number of zooplankton recruited into the pond from the inlet water, after the prawns were stocked, was negligible and contributed little to changes observed in zooplankton assemblages. Reproduction of barnacles within the pond appeared to play the most important role in changes in the assemblage. Water exchange did, however, appear to play a greater role in the changes observed in epibenthic fauna assemblages. In the last season of sampling the feeding of the dominant epibenthic species, Acetes sibogae, was examined using a combination of gut content and stable isotope analysis. Acetes gained little nutrition directly from the pelleted feed, probably relying primarily on zooplankton as their direct food source. Other dietary items such as macroalgae also played a role in the nutrition of the Acetes. If Acetes numbers were high at the beginning of a season they may compete with the newly stocked prawns for the zooplankton resource. However, they will not compete with the prawns later in the season when the prawns are gaining most of their nutrition from the pelleted feed. Overall it appears that zooplankton are important to the nutrition of the prawns at the beginning of the season when the assemblage is usually dominated by copepods. Later in the season the assemblage is dominated by barnacle nauplii which are recruited from within the pond. The establishment of an abundant assemblage of suitable zooplankton species before stocking prawn postlarvae would appear to be beneficial, if not essential. The assemblage of epibenthic fauna changes throughout the season as new recruits are brought in from outside the pond. Epibenthic faunal assemblages in ponds from southeast Queensland are dominated by Acetes which are not likely to adversely affect the production of prawns unless they are particularly abundant early in the grow out season when the prawns would be utilising the same food resources as Acetes.
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Coman, Francis Edmund. "The Role of Epibenthic and Planktonic Fauna in Subtropical Prawn Grow Out Ponds". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/367812.
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The assemblage composition, biomass and dynamics of zooplankton and epibenthos were examined in a commercial prawn pond in southeast Queensland over two seasons. Physico-chemical characteristics of the pond water were measured concurrently. Numbers and biomass of zooplankton in the surface tows (140 micrometre mesh) varied from 8 ind. L-1 (44 micrograms L-1) to 112 ind. L-1 (324 micrograms L-1) in the first season, with peaks in biomass corresponding to peaks in numbers. In the second season the zooplankton numbers varied from 12 to 590 ind. L-1, but peaks in numbers did not correspond with peaks in biomass, which varied from 28 to 465 micrograms L-1. This was due to differences in the size of the dominant taxa across the season. Although this occurred in both seasons, the effect on biomass was more pronounced in the second season. In both seasons, immediately after the ponds were stocked with prawn postlarvae there was a rapid decline in zooplankton numbers, particularly of the dominant larger copepods. This was probably due to predation by the postlarvae. Subsequent peaks in zooplankton numbers were principally due to barnacle nauplii. The largest peaks in zooplankton numbers occurred before stocking in the first season, but the largest peaks were in the middle of the second season. While changes in abundance and biomass of the zooplankton assemblage were not correlated with physico-chemical characteristics in the first season, there were correlations between zooplankton numbers and temperature, dissolved oxygen, pH and secchi disk readings in the second season. No correlations were found with zooplankton biomass and physico-chemical characteristics in the second season. The correlations in the second season were mainly due to the high prevalence of barnacle nauplii through the middle part of the season, and may reflect suitable conditions for barnacle reproduction. Epibenthic faunal abundance in the beam trawls (1 mm mesh) peaked at 14 ind. m-2 and 7 ind. m-2 in the first and second seasons respectively and the biomasses at 0.8 g m-2 and 0.7 g m-2. Peaks in abundance of epibenthos did not correspond to peaks in biomass. This was due to large differences in the size of the taxa across the seasons. Sergestids (Acetes sibogae) and amphipods were the most abundant taxa in beam trawl samples. Amphipods were only abundant in the first season, with their numbers increasing towards the end of the grow out period. Acetes were abundant in both seasons, but were dominant in the second season. Correlations between physico-chemical parameters and epibenthos numbers were found to be strongly influenced by the dominant taxa in each season. In the first season, negative correlations were found between epibenthos abundance and pH and temperature. These relationships may reflect an effect on the growth of macroalgae in the pond, with which the amphipods were strongly associated, rather than a direct effect on the epibenthos. In the second season, a positive correlation existed between temperature and epibenthos abundance, however this was strongly influenced by the very high abundance of Acetes in the last sampling period. No correlations were found between epibenthic fauna biomass and physico-chemical parameters. Abundances of epibenthic fauna were not related to zooplankton densities indicating this source of food was not likely to be a limiting factor. Neither the pond water exchange regime nor moon phase could explain changes observed in abundances of zooplankton or epibenthos assemblages in the first season, however the sampling regime was not designed to specifically investigate these effects. In the second season water exchanges were sampled more rigorously. The density of zooplankton in the outlet water was from 2 to 59% of the density of zooplankton in the pond, and the zooplankton density of the inlet water was from 9 to 50% of the outlet water. The number of zooplankton recruited into the pond from the inlet water, after the prawns were stocked, was negligible and contributed little to changes observed in zooplankton assemblages. Reproduction of barnacles within the pond appeared to play the most important role in changes in the assemblage. Water exchange did, however, appear to play a greater role in the changes observed in epibenthic fauna assemblages. In the last season of sampling the feeding of the dominant epibenthic species, Acetes sibogae, was examined using a combination of gut content and stable isotope analysis. Acetes gained little nutrition directly from the pelleted feed, probably relying primarily on zooplankton as their direct food source. Other dietary items such as macroalgae also played a role in the nutrition of the Acetes. If Acetes numbers were high at the beginning of a season they may compete with the newly stocked prawns for the zooplankton resource. However, they will not compete with the prawns later in the season when the prawns are gaining most of their nutrition from the pelleted feed. Overall it appears that zooplankton are important to the nutrition of the prawns at the beginning of the season when the assemblage is usually dominated by copepods. Later in the season the assemblage is dominated by barnacle nauplii which are recruited from within the pond. The establishment of an abundant assemblage of suitable zooplankton species before stocking prawn postlarvae would appear to be beneficial, if not essential. The assemblage of epibenthic fauna changes throughout the season as new recruits are brought in from outside the pond. Epibenthic faunal assemblages in ponds from southeast Queensland are dominated by Acetes which are not likely to adversely affect the production of prawns unless they are particularly abundant early in the grow out season when the prawns would be utilising the same food resources as Acetes.Thesis (Masters)
Master of Philosophy (MPhil)
School of Environmental and Applied Science
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Bauermeister, Jan [Verfasser], Sharmishtha [Akademischer Betreuer] Dattagupta i Volker [Akademischer Betreuer] Thiel. "Diversity and ecology of ectosymbioses between sulfur-oxidizing Thiothrix bacteria and groundwater niphargid amphipods / Jan Bauermeister. Gutachter: Sharmishtha Dattagupta ; Volker Thiel. Betreuer: Sharmishtha Dattagupta". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044173114/34.
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