Age-0 largemouth bass Micropterus salmoides were studied in Bay Springs Reservoir, Mississippi, to determine if the larger young had greater survival through their first winter and this was influenced by levels of energy reserves. Abundance decreased from 542 young/ hectare June, when fish averaged 37 mm total length, 12/hectare March, lengths 149 mm. The length-frequency distribution year–class positively skewed during June–August, became bimodal September–January, lost most smaller mode...

Fish size and electrical waveforms have frequently been associated with variation in electrofishing effectiveness. Under controlled laboratory conditions, we measured the power required by five to immobilize eight fish species of diverse sizes shapes. was indexed total body length, surface area, volume, weight; shape ratio length depth. Our objectives were identify immobilization thresholds, elucidate descriptors that best those determine whether vulnerability a relative other remained...

Winter mortality of age-0 largemouth bass Micropterus salmoides is sometimes size dependent, with smaller fish experiencing higher mortality. We conducted this study to determine if the presence predators influenced winter young bass, all sizes equally, and increased shelter availability moderated a possible relation between predator-induced size, stocked 0.06-ha experimental ponds (30 fish/pond) five length groups (55–100, 101–125, 126–150, 151–175, 176–200 mm total length), without (three...

Abstract The alluvial valley of the lower Mississippi River contains hundreds fluvial lakes that are periodically connected to river during high water, although frequency, duration, and timing connections vary. To help design plans restore preserve fish assemblages in these lakes, this investigation tested whether predictable patterns lake were linked level connectivity with river. Results suggested played an important role structuring it was correlated variables such as size, depth,...

Climate change is the defining environmental problem for our generation. The effects of climate are increasingly evident and anticipated to profoundly affect ability conserve fish habitats assemblages. Reservoirs important structures coping with projected shifts in water supply, but they also provide refuge riverine fishes retain distinct assemblages that support diverse fisheries. on reservoirs unique among aquatic systems because have distinctive habitat characteristics due their...

Migratory behaviour of selected fish species is described in the Paraná River, Brazil–Argentina–Paraguay, to search for patterns relevant tropical regulated river systems. In a 10 year mark–recapture study, spanning 1425 km section river, 32 867 fishes composed 18 were released and 1083 recaptured. The recaptured at liberty an average 166 days (maximum 1548 days) travelled 35 (range 0–625 km). Cluster analysis applied variables descriptive movement identified four general patterns. 1...

Abstract Regulation of rivers by dams transforms previously lotic reaches above the dam into lentic ones and limits or prevents longitudinal connectivity, which impairs access to suitable habitats for reproduction many migratory fish species. Frequently, unregulated tributaries can provide important habitat heterogeneity a regulated river may mitigate influence impoundments on mainstem river. We evaluated importance spawning species over three seasons, comparing several abiotic conditions...

ABSTRACT Hydrologic connectivity is a crucial determinant of aquatic ecosystem services, governing the exchange nutrients, sediments, chemicals, and biota. Various indices metrics exist for quantifying hydrologic across diverse environments scales. However, existing methodologies often fail to adequately capture lateral between lakes streams vast, low‐relief, multi‐lake floodplain systems. This study introduces novel approach specifically tailored connecting within expansive Lower...

Abstract The compensatory mortality hypothesis postulates that a population's total remains unchanged at low to intermediate exploitation rates because natural decreases compensate for reduced density, whereas the additive any increase in results an mortality. Fishing and have generally been assumed be rather than compensatory. We reviewed estimates some prominent sportfish populations identify evidence or For largemouth bass Micropterus salmoides , annual increased with suggesting crappies...

We used an equilibrium yield model to simulate the effect of reducing exploitation on and average weight white crappies Pomoxis annularis, based empirical growth data various levels conditional natural mortality. Modeling indicated that would likely increase as fish increased mortality decreased; however, not substantially affect when exceeded 30–40%, regardless growth. For instance, a 250-mm minimum length limit provided higher than 200-mm only if was above less 30–40%. Average harvested...

Juvenile largemouth bass Micropterus salmoides were collected by electrofishing during October through March 1992–1994 from coves (≤25 ha) covered with aquatic macrophytes over 1–65% of their area. Mean total length juvenile was highest in the least vegetated cover, but increase mean between and having near 20% vegetation coverage. Catch per unit effort decreased March; decreases at coverages 10–20%, 5% or less, intermediate 30–65%. By March, these disparate contributed to formation a...

We investigated the effect of parental body length on swim-up date and larval largemouth bass Micropterus salmoides in experimental ponds, length, growth, survival three reservoirs. Swim-up was estimated from counts daily growth rings otoliths. Larvae spawned by larger adults had significantly more same sampling than larvae smaller parents, indicating that earlier. Length at independent did not produce larvae. Positive correlations between age total indicated initial advantages resulting...

Water level manipulation was examined as a potential management technique for increasing recruitment of largemouth bass (Micropterus salmoides) in reservoir where prey availability and utilization were major factors influencing the population. Raising water above normal summer pool inundated terrestrial vegetation provided cover young-of-year (YOY) bass. A positive relationship observed between early survival YOY during spawning period. In post-spawning period, rate abundance related...

Miyazono S, Aycock JN, Miranda LE, Tietjen TE. Assemblage patterns of fish functional groups relative to habitat connectivity and conditions in floodplain lakes. Ecology Freshwater Fish 2010: 19: 578–585. © 2010 John Wiley & Sons A/S Abstract – We evaluated the influences local environmental factors on distribution abundance 17 lakes Yazoo River Basin, USA. The results univariate multivariate analyses showed that species–environmental relationships varied with groups. Species richness...

ABSTRACT Populations show spatial-temporal fluctuations in abundance, partly due to random processes and self-regulatory processes. We evaluated the effects of various external factors on population numerical abundance curimba Prochilodus lineatus upper Paraná River floodplain, Brazil, over a 19-year period. Panel data analysis was applied examine structure temporal spatial while controlling auto-regressive non-homogeneity variances that often obscure relationships. As sources variation, we...

Abstract Conservation of fish assemblages in severely impounded rivers has often focused on providing longitudinal and lateral connectivity along the main stem. Less attention been given to tributaries, some which remain unimpounded. This study shows that biodiversity ichthyoplankton tributaries largest reservoir Paraná River, Brazil, is similar few remaining unimpounded stretches River. Annual seasonal variability discharge within among attracts supports a diverse mix species each spawning...

A qualitative comparative approach has been used to review whether fish assemblage characteristics, such as paucity of lacustrine-adapted species, long food chains, and disproportionate number piscivorous limit fishery yields in reservoirs the Upper Paraná River basin. The species appears yields, but attempts introduce lacustrine have generally unsuccessful. chains targeted by fisheries are relatively long, short seem be an adaptation species. Because with many sustain high elsewhere world,...

1. Aquatic plants add structural complexity to aquatic environments, provide resources for the food web and generally promote diversity stability of fauna. However, also alter abiotic properties water at high densities can produce physical chemical conditions intolerable fish. 2. We identified substantial horizontal vertical, as well spatial temporal, variability in oxygen temperature over micro‐scales within macrophyte stands. Areas with suitable dissolved occurred close areas hypoxic...

Over 6,000 crappies Pomoxis spp. were tagged in five water bodies to estimate exploitation rates by anglers. Exploitation computed as the percentage of tags returned after adjustment for three sources uncertainty: postrelease mortality due tagging process, tag loss, and reporting rate fish. Confidence intervals around estimated resampling from probability distributions mortality, rate. Estimates ranged 17% 54% among study systems. Uncertainty estimates resulted 90% confidence median narrow...