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Exhippolysmata oplophoroides (Holthuis, 1948) e Nematopalaemon schmitti (Holthuis, 1950: Pleocyemata) : dinâmica populacional em dois períodos distintos com um intervalo de onze anos na Enseada de Ubatuba, SP, Brasil /Carneiro, Alessandra Paula. January 2012 (has links)
Orientador: Adilson Fransozo / Banca: Antônio Leão Castilho / Banca: Valter Jose Cobo / Resumo: Para entender as características distribucionais de algumas espécies, é preciso conhecer sua história de vida, os recursos que requerem, e as interações intra e inter-especificas além dos efeitos exercidos pelas condições ambientais. O presente estudo teve como objetivo verificar a distribuição espacial e temporal de duas espécies de carídeos Exhippolysmata oplophoroides e Nematopalaemon schmitti na Enseada de Ubatuba, São Paulo, em quatro pontos amostrais (10m, 20m, área batida e área abrigada) e em dois períodos distintos compreendidos num intervalo de 11 anos, e a sua relação com as variáveis ambientais. Os camarões foram coletados usando um barco camaroneiro equipado com rede do tipo ‚double-rig‛. Ao longo dos dois anos, foram coletados 4445 indivíduos de N. schmitti e 4995 E. oplophoroides, sendo que o primeiro ano foi estatisticamente mais abundante para ambas as espécies (ANOVA, p < 0,05). A distribuição dos carídeos foi diferencial ao longo dos transecto (ANOVA, p < 0,05), havendo grande frequência dos camarões no transecto batido. A abundância de E. oplophoroides e N. schmitti apresentou relação positiva com granulometria do substrato e negativa com o teor de matéria orgânica (Regressão Múltipla, p< 0,05). Esses dois fatores variaram espacialmente, o que pode justificar a heterogeneidade na distribuição dos carídeos ao longo dos transectos. N. schmitti ocorreu sazonalmente, com picos de incidência no inverno e outono, enquanto E. oplophoroides apresentou ocorrência diluída em todas as estações sazonais. Pode-se inferir que a retração da ACAS de dentro da Enseada, no inicio do outono influencie na presença de N. schmitti no ambiente estudado. O declínio na abundância de ambas... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Not available / Mestre
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The Plankton of the Bear River Migratory Waterfowl Refuge, Utah Seasonal Distribution of OrganismsPiranian, George 01 May 1937 (has links)
In the summer of 1932, an investigation of some biological, physical, and chemical conditions at the Bear River Migratory Waterfowl Refuge, Utah, was begun at the Utah State Agricultural College to determine some of the factors governing the biological productivity of brackish-water marshes. Unfortunately, lack of funds made it impossible to continue work beyond the first season.
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Seasonal Distribution of Sage-Grouse in Hamlin Valley, Utah and the Effect of Fences on Grouse and Avian PredatorsMcPherron, Heather Hedden 01 December 2017 (has links)
Greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse) numbers have declined throughout the western US and are considered a species of concern in most of the eleven states that are within their range. Sage-grouse habitats have been reduced by approximately 44% since European settlement of the Western United States began (Miller et al. 2011). Loss of habitat has contributed to an average decline of sage-grouse populations by 33% across the range (Connelly and Braun 1997). To expand our knowledge of this species, I monitored 16 radio-collared sage-grouse captured from four leks in Hamlin Valley, Utah, USA in 2011 and 2012 to determine habitat use. The Hamlin Valley population was primarily one-stage migratory but non-migratory behaviors were also observed. Birds from at least one of the leks used seasonal habitats in neighboring Nevada.
Sage-grouse evolved in habitats where infrastructure (e.g. vertical structures) was not common. Introduction of infrastructure, such as fences in their habitat, can cause direct mortality via collision but may also indirectly influence productivity by increasing artificial perches for avian predators (e.g. golden eagles (Aquila chrysaetos) , red-tailed hawks (Buteo jamaicensis), and common ravens (Corvus corax). This research focused on collision rates and increased potential for avian predation on two small populations on the southern portion of the range of current occupied sage-grouse habitat in southwestern vi Utah. During 2011-2012, over 450 km of fences were surveyed for signs of collision and use by avian predators during all seasons (breeding, fall migration, and winter). No sage-grouse collisions were observed suggesting that management for sage-grouse in small populations may be better focused on improving habitat and reducing other causes of mortality which may be more prevalent. Fence post width (i.e. the perching surface) was the best predictor of use as perch by avian predators. Additionally, areas farther from other natural perches, with a low density of surrounding vegetation, and fences constructed along defined habitat edges were used by avian predators more frequently. Results of this study suggest that managers should construct fences with small widths to deter avian predators and care should be taken to maintain contiguous vegetation on either side of the posts while maintaining low shrub density.
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Seasonal shifts in redband trout use of pools and their microhabitats in three central Oregon streamsHirsch, Christine L. 31 October 1995 (has links)
Redband trout density was examined in three forested streams in central
Oregon at two scales, pool channel unit and microhabitat. Two streams were in
roadless areas and one was in a "highly managed" watershed. At the larger
spatial scale, trout displayed a seasonal shift in habitat use from early to late
summer. There was a positive correlation between trout density and pool
structural complexity during summer base flow. The association was intensified
throughout the summer as stream flow continued to drop. The structural
complexity of each pool was quantified using an index integrating structural
variability and depth. Twenty-two pools were divided into microhabitats, or pool
subunits with similar characteristics using a qualitative classification scheme
describing different structural elements comprising the pool habitat. Microhabitat
was partitioned between fry and older trout throughout the summer: Fry generally
used stream margins, backwaters, and shallow areas; whereas, trout one year
and older used deep areas (depth greater that 0.5 m) and cover associated with
substrate and wood. The use of cover by trout one year and older doubled from
June to August. This change in use was coupled with the increased association
with structural complexity at the channel unit scale. The large substrate and
wood that provided cover also increased the structural complexity of the pool.
As trout increased their use of cover, their densities increased in more complex
pools.
Man-made log weir pools in a simplified stream were evaluated for their
structural complexity and compared to the shallow natural pools in the same
reach. Log weir pools had greater average depth, but were less complex than
natural pools, and could maintain a similar density of trout. The structural
complexity in natural pools appears to compensate for their shallow depth. Log
weir pools enhanced with placement of a rootwad supported higher densities of
trout. Addition of a rootwad provided microhabitats associated with cover that
were lacking in weir pools without other structures added. When using instream
construction to create pool habitat, complex structure that provides microhabitats
associated with cover is more effective at holding higher densities of fish under
late summer low flow conditions. / Graduation date: 1996
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Spatial and Seasonal Distribution of Ticks and Intestinal Helminths in Siberian Weasel (Mustela sibirica) in ShanpingChen, Chen-Chih 17 February 2003 (has links)
ABSTRACT
The epidemiological study of intestinal helminths and ticks of Siberian weasel (Mustela sibirica) was conducted from June 2001 to May 2002 in Shan-Ping, southern Taiwan. Nine helminths were found, including seven nematodes, Filaroides sp. (prevalence 94.4%), Ancylostoma sp. (77.4%), Uncinaria sp. (35.5%), Trichuris sp. 1 (35.5%), Trichuris sp. 2 (19.3%), Capillaria sp. (6.5%) and Physaloptera sp. (3.2%); one trematode, Platynosomum sp. (74.1%) and one acanthocephalans, Macracanthorhynchus sp. (10%). There was a significant seasonal difference of intensity of the Platynosomum sp. Two species of ticks were observed, Ixodes ovatus (prevalence 55.56%) and Haemaphysalis sp. Seasonal differences were significant in the prevalence and intensity of the Ixodes ovatus infection. The intensities of ticks and helminths in different sampling area were similar. The diet composition was possibly the factor affecting the seasonal change of intensity of the Platynosomum sp. and host availability affecting the seasonal change of ticks, Ixodes ovatus.
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Some effects of salinity on the population dynamics and reproductive biology of the nudibranch Hermissenda crassicornisManley, Wendy Lou January 1987 (has links)
ix, 62 leaves : ill. ; 29 cm
Notes Typescript
Thesis (M.S.)--University of Oregon, 1987
Includes vita and abstract
Bibliography: leaves 59-62
Another copy on microfilm is located in Archives
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Composição e diversidade dos camarões marinhos (Crustacea: Decapoda: Penaeoidea) e dinâmica populacional de Xiphopenaeus kroyeri (Heller, 1862) no litoral do BrasilAlmeida, Ariádine Cristine [UNESP] 24 September 2012 (has links) (PDF)
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almeida_ac_dr_botib.pdf: 859822 bytes, checksum: c0f964299ecfb510e7f66b1eea006b46 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The spatial and temporal patterns of abundance and distribution of Xiphopenaeus kroyeri and its relationship with several environmental variables were compared over a range of 20 years. The abiotic and biotic data set were obtained monthly during two distinct study periods; period 1, from November 1988 to October 1989; and period 2, from November 2008 to October 2009, in seven permanent transects established within Fortaleza Bay, on the southeastern coast of Brazil. A remarkable sedimentation was observed between the first and the second study periods, which might have been caused by natural phenomena and/or human activities. While the variations in the bottom temperature and salinity were related mainly to the hydrodynamics of water masses present in the Ubatuba region. The abundance of X. kroyeri increased considerably over a range of 20 years. A total of 13 298 and 39 553 specimens were obtained throughout the sampling periods 1 and 2, respectively. The total abundance of the species and the abundance of males and females differed spatially, while the abundance of juveniles differed seasonally, during each study period (ANOVA, p < 0.05). Overall, the highest abundance of the species was recorded in those transects which the sediment was composed mainly by fine and very fine sand and silt and clay. The presence of algae and plant floating near the marine floor at Fortaleza Bay also favored the occurrence and settlement of X. kroyeri. Interestingly, during period 1 the species was most abundant in winter, when bottom temperature reached low mean value (21.6°C). While during period 2, the highest abundance of X. kroyeri was obtained in summer and fall. Concomitantly, the highest mean values of bottom temperature were recorded during these seasons (25.2 and 24.5°C, respectively). So, the... (Complete abstract click electronic access below)
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Composição e diversidade dos camarões marinhos (Crustacea: Decapoda: Penaeoidea) e dinâmica populacional de Xiphopenaeus kroyeri (Heller, 1862) no litoral do Brasil /Almeida, Ariádine Cristine. January 2012 (has links)
Orientador: Adilson Fransozo / Banca: Roberto Munehisa Shimizu / Banca: Fúlvio Aurélio de Moraes Freire / Banca: Gustavo Monteiro Teixeira / Banca: Rogério Caetano da Costa / Resumo: Não disponível / Abstract: The spatial and temporal patterns of abundance and distribution of Xiphopenaeus kroyeri and its relationship with several environmental variables were compared over a range of 20 years. The abiotic and biotic data set were obtained monthly during two distinct study periods; period 1, from November 1988 to October 1989; and period 2, from November 2008 to October 2009, in seven permanent transects established within Fortaleza Bay, on the southeastern coast of Brazil. A remarkable sedimentation was observed between the first and the second study periods, which might have been caused by natural phenomena and/or human activities. While the variations in the bottom temperature and salinity were related mainly to the hydrodynamics of water masses present in the Ubatuba region. The abundance of X. kroyeri increased considerably over a range of 20 years. A total of 13 298 and 39 553 specimens were obtained throughout the sampling periods 1 and 2, respectively. The total abundance of the species and the abundance of males and females differed spatially, while the abundance of juveniles differed seasonally, during each study period (ANOVA, p < 0.05). Overall, the highest abundance of the species was recorded in those transects which the sediment was composed mainly by fine and very fine sand and silt and clay. The presence of algae and plant floating near the marine floor at Fortaleza Bay also favored the occurrence and settlement of X. kroyeri. Interestingly, during period 1 the species was most abundant in winter, when bottom temperature reached low mean value (21.6°C). While during period 2, the highest abundance of X. kroyeri was obtained in summer and fall. Concomitantly, the highest mean values of bottom temperature were recorded during these seasons (25.2 and 24.5°C, respectively). So, the... (Complete abstract click electronic access below) / Doutor
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Biology of immature Culicoides variipennis ssp. australis (Coq.) (Diptera:Ceratopogonidae) at Saltville, VAVaughan, Jefferson Archer January 1985 (has links)
The larval and pupal biology of a unique population of gulicoides variipennis inhabiting the brine ponds of Saltville, VA was studied. Developmental threshold temperatures (OC) and thermal constants (Odays) for larvae and pupae were 9.6OC and 387Odays (larval stage) and 9.6OC and 3OOdays (pupal stage) respectively. Accumulated heat units recorded in the field ranged from 366—376Odays between successive generations in the summer. Heat accumulations required for completion of immature development of Q. variipennis were found to be much greater (83lOdays) for the overwintering generation. During the summer, larval/pupal distribution within the littoral zone of a brine pond was confined to the surface cm of mud at or near the shoreline. Insects overwintered farther offshore, mostly as 3rd instars. In ear1y' March, most larvae had xnolted to 4th instars and migrated above shoreline to pupate. Adult emergence occurred in April. Three summer generations were documented for 1983-1984 at Saltville._ Life tables and survivorship curves were calculated for the overwintering generation and the first summer generations for 1983 and 1984. For the overwintering generation, there was a relatively constant mortality rate between successive ageclasses (Type II survivorship curve). During the summer, there was relatively little mortality between successive larval age—classes but a dramatic increase in mortality was evident at the pupal stage (Type I survivorship curve). Late instar larvae were found to migrate from the shoreline onto the exposed mudflats to pupate, thus becoming vulnerable to predation by ants and carabid beetles. Excellent survival rates of the larvae during the summer was attributed to habitat stability, the paucity of predators and parasites and abundant microfloral content (i.e. food} of the pond water. Intra-specific competition for food resources appeared to be alleviated somewhat by partitioning of those resources on a diurnal cycle. / Ph. D.
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Environmental factors related to the abundance and distribution of brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) and seasonal movements of brown trout in selected Virginia streamsJosephson, Daniel C. January 1983 (has links)
The relationships between brook trout (Salvelinus fontinalis), brown trout (Salmo trutta), non-game fish populations and selected physical and chemical parameters were investigated in four streams draining the Blue Ridge Mountains in north-central Virginia during low flow conditions in August, 1981 and 1982. Multiple regression and discriminant function analysis identified average stream width and maximum stream temperature as the main environmental factors related to brook and brown trout abundance and distribution. Furthermore, consistent fish species assemblages relative to brown trout distribution were observed in the study streams.
The movements of tagged brown trout in two streams were assessed for the period from June 1981 to July 1982. Most brown trout remained within 200 m of original tagging sections, 98.7% in the Conway River (78 out of 79) and 71.4% in the North Fork Thornton River (7 out of 9). The 1979, 1978 and 1977 year class fish (ages 2+, 3+ and 4+) exhibited extremely restricted movements and were invariably recaptured at original capture locations while the 1980 year class (age 1+) displayed small net upstream movements (<80 m) throughout the period. Two 1980 year class individuals displayed extensive movements (17.0 km downstream and 1.2 km upstream). These movements were characteristic of other stream resident brown trout populations.
Results of this study suggest that brown trout may expand their range upstream into currently allopatric brook trout zones. It would likely be a slow but steady process which could be accelerated by infrequent long-range movements. The potential for establishment of reproducing brown trout populations and impacts of brown trout on native brook trout populations can be assessed utilizing fish species assemblages, average stream width and maximum stream temperature prior to further brown trout introductions in this region of Virginia. / Master of Science
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