Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Author(s):  
Keyword(s):  
Water Quality ◽  
Waste Treatment ◽  
Fish Assemblages ◽  
Large River ◽  
Low Flow ◽  
Physical Habitat ◽  
Willamette River ◽  
Habitat Alterations ◽  
The Past ◽  
Species Occurrences

<em>Abstract.</em>—The Willamette River is Oregon’s largest river, with a basin area of 29,800 km<sup>2</sup> and a mean annual discharge of 680 m<sup>3</sup>/s. Beginning in the 1890s, the channel was greatly simplified for navigation. By the 1940s, it was polluted by organic wastes, which resulted in low dissolved oxygen concentrations and floating and benthic sludge deposits that hindered salmon migration and boating. Following basin-wide secondary waste treatment and low-flow augmentation, water quality markedly improved, salmon runs returned, and recreational uses increased. However, water pollution remains a problem as do physical habitat alterations, flow modification, and alien species. Fish assemblages in the main-stem Willamette River were sampled systematically, but with different gear, in the summers of 1945, 1983, and 1999. In the past 53 years, tolerant species occurrences decreased and intolerant species occurrences increased. In the past 20 years, alien fishes have expanded their ranges in the river, and four native fish species have been listed as threatened or endangered. We associate these changes with improved water quality between 1945 and 1983, fish migrations, altered flow regimes and physical habitat structure, and more extensive sampling.

From Catastrophe to Recovery: Stories of Fishery Management Success

2019 ◽  
Keyword(s):  
Water Quality ◽  
Rainbow Trout ◽  
Endangered Species ◽  
Fish Assemblages ◽  
Native Fish ◽  
Physical Habitat ◽  
Land Trusts ◽  
Municipal Governments ◽  
Willamette River ◽  
Nonnative Fish

<i>Abstract.</i>—Fish assemblages in the Willamette River basin (Oregon) were once substantially degraded by water pollution, channelization, dams, nonnative fish, and conversion of natural forest and savanna to agriculture and urbanization. Restoration actions have included basinwide waste treatment, physical habitat rehabilitation, recovery of the Oregon Chub <i>Oregonichthys crameri</i> to stable status, and stocking reductions of nonnative fish to protect native fish. State and federal sewage treatment regulations and funding, federal endangered species regulations and funding, and reduced funding and support for stocking nonnative trout led to those rehabilitated fish assemblages. Periodic fish and habitat monitoring has documented the following improvements in fish assemblages: (1) decreased occurrences of pollution-tolerant species and increased occurrences of pollution-sensitive species and native main-stem species, (2) increased number of abundant Oregon Chub populations, and (3) persistence of resident native Rainbow Trout <i>Oncorhynchus mykiss</i>. Notably, no known extinctions of native fish species have occurred in the Willamette River, water quality index scores in the lower river have improved from poor to fair, and water quality in the upper river remains good to excellent. In conclusion, enactment of laws and regulations for environmental protection and the collective actions of state and federal agencies, tribes, municipal governments, universities, land trusts and conservation groups, watershed councils, and private landowners have led to a substantially rehabilitated river. However, population and economic growth, climate change, nonnative fish, winter steelhead (anadromous Rainbow Trout) and spring Chinook Salmon <i>O. tshawytscha</i> listings, a superfund site, channel alterations, toxic substances, poor fish passage at dams, and altered flow regimes remain challenges. Four lessons learned are that (1) pollution control and improved water quality and flows are essential to the recovery and persistence of native fish populations, (2) recovery of endangered species is achievable but requires knowledge of their life history needs, (3) the greater ecological fitness of native stocks facilitates their persistence, and (4) research and monitoring, combined with public communication and collaboration, are essential for habitat and native fish assemblage rehabilitation.

Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Keyword(s):  
Alien Species ◽  
Environmental Changes ◽  
Fish Assemblages ◽  
Fish Fauna ◽  
Large River ◽  
Gold Rush ◽  
Physical Habitat ◽  
San Joaquin River ◽  
The Status ◽  
Native Fishes

<em>Abstract.</em>—In this paper, we review information regarding the status of the native fishes of the combined Sacramento River and San Joaquin River drainages (hereinafter the “Sacramento–San Joaquin drainage”) and the factors associated with their declines. The Sacramento–San Joaquin drainage is the center of fish evolution in California, giving rise to 17 endemic species of a total native fish fauna of 28 species. Rapid changes in land use and water use beginning with the Gold Rush in the 1850s and continuing to the present have resulted in the extinction, extirpation, and reduction in range and abundance of the native fishes. Multiple factors are associated with the declines of native fishes, including habitat alteration and loss, water storage and diversion, flow alteration, water quality, and invasions of alien species. Although native fishes can be quite tolerant of stressful physical conditions, in some rivers of the drainage the physical habitat has been altered to the extent that it is now more suited for alien species. This interaction of environmental changes and invasions of alien species makes it difficult to predict the benefits of restoration efforts to native fishes. Possible effects of climate change on California’s aquatic habitats add additional complexity to restoration of native fishes. Unless protection and restoration of native fishes is explicitly considered in future water management decisions, declines are likely to continue.

Landscape Influences on Stream Habitats and Biological Assemblages

2006 ◽  
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Fish Assemblages ◽  
Stream Water ◽  
Riparian Buffers ◽  
Physical Habitat ◽  
Land Uses ◽  
Stream Water Quality ◽  
Agricultural Streams ◽  
And Function

<em>Abstract.</em>—Ecologists recognize that surrounding land use can influence the structure and function of aquatic ecosystems, but few studies have explicitly examined the relative effects of different types of land use on stream ecosystems. We quantified the relationships between different land uses (forested, urban, agricultural with or without riparian buffers) and stream physicochemical variables and resident fish assemblages in 21 southwestern Michigan streams. These streams were located within a single basin (Kalamazoo River) and ecoregion to minimize differences in natural landscape conditions. Streams responded to a gradient of land use, with forested streams having the least degraded water quality, physical habitat, and fish assemblages, and agricultural streams lacking buffers being the most degraded. Urban and agricultural streams with buffers displayed characteristics intermediate to forested and agricultural streams lacking buffers. In general, habitat complexity and water quality declined across this land-use gradient from forested to agricultural streams, whereas fish density, richness, and dominance by tolerant species increased along the land-use gradient. Although urban streams had lower percentages of altered land use (i.e., <40% urban) in their catchments compared to agricultural streams (i.e., >50% agriculture), both land uses appeared to have similar detrimental effects on streams suggesting higher per unit area impacts of urbanization on streams. The presence of forested riparian buffers along agricultural streams increased the complexity of instream habitat, but resulted in few benefits to fish assemblages, suggesting that stream water quality in altered landscapes may be constraining fish assemblages more than physical habitat.

Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Keyword(s):  
Fish Species ◽  
Colorado River ◽  
Fish Assemblages ◽  
Large River ◽  
Management Program ◽  
Federal State ◽  
Physical Habitat ◽  
Management Actions ◽  
Cooperative Agreements ◽  
Warm Springs

<em>Abstract.</em>—The upper Colorado River basin supports a native ichthyofauna of 14 species or subspecies that have been impacted by poor land-use practices, altered flows, physical habitat fragmentation, competition and predation from nonnative fish species, and degraded water quality. Five taxa are federally endangered, including the large-river species, Colorado pikeminnow <em>Ptychocheilus lucius</em>, humpback chub <em>Gila cypha</em>, bonytail <em>G. elegans</em>, razorback sucker <em>Xyrauchen texanus</em>, and a warm-stream subspecies, Kendall Warm Springs dace <em>Rhinichthys osculus thermalis</em>. Two recovery programs, formed through cooperative agreements among federal, state, tribal, and private agencies and stakeholders, coordinate activities in the upper basin that have helped to resolve water resource issues, implement management actions to minimize or remove threats, and conserve endangered species. A cooperative biological management program among state and federal agencies works to protect the Kendall Warm Springs dace. Conservation agreements have also been established for the other native fish species. Continued public and institutional support for these programs is vital to species recovery and to the balance between long-term species conservation and human demands on the Colorado River system.

scholarly journals Longitudinal patterns in fish and macrozoobenthos assemblages reflect degradation of water quality and physical habitat in the Bílina river basin

2010 ◽  
Vol 55 (No. 3) ◽  
pp. 123-136 ◽  
Author(s):  
P. Jurajda ◽  
Z. Adámek ◽  
M. Janáč ◽  
Z. Valová
Keyword(s):  
Water Quality ◽  
Species Richness ◽  
River Basin ◽  
Fish Species ◽  
Fish Assemblages ◽  
Physical Habitat ◽  
Elbe River ◽  
River Stretch ◽  
The Elbe River ◽  
Bílina River

The aim of this study was to provide the first account of fish and macroinvertebrate communities in a heavily degraded river basin in the Czech Republic. Fish and macrozoobenthos were surveyed at 18 sites in the Bílina River and 11 sites in tributary streams during June–July 2007. Fish were sampled by electrofishing and macrozoobenthos were collected by kick-sampling using a sweep net. The composition of macroinvertebrate assemblages in headwater and reference sites in the upper Bílina River indicated clean water with saprobic index (SI) 1.31–1.43 followed by a transitional stretch downstream the Kyjická reservoir (SI 2.05–2.32) and dramatic decline of water quality to SI 3.18 in the river stretch downstream of industrial and municipal pollution at Litvínov-Záluží. Despite several minor pollution sources on the subsequent downstream river stretch until its mouth into the Elbe River, the water quality indicators fluctuated in the range of lower betamesosaprobity (SI 2.06–2.58). Species richness and biodiversity indices followed a similar pattern as river saprobity. Twenty-three fish species were documented in the Bílina River basin. Chub (<I>Leuciscus cephalus</I>), gudgeon (<I>Gobio gobio</I>) and roach (<I>Rutilus rutilus</I>) were the most frequent species at the Bílina sites. Chub was the most numerous fish in the tributaries. Fish species richness in the longitudinal profile did not increase downstream in the Bílina mainstem, most likely because the presence of reservoirs and water pollution interrupted the river continuum pattern. Qualitative data on fish assemblages corresponded to the course of environmental stress. A sustainable fish community was documented only in the lowermost site in Ústí nad&nbsp;Labem near the confluence with the Elbe River. The Bílina River tributaries constitute potential refuges for fish in this basin.

Mitigating Impacts of Natural Hazards on Fishery Ecosystems

2008 ◽  
Keyword(s):  
Water Quality ◽  
Nutrient Loading ◽  
Water Quality Management ◽  
River Estuary ◽  
Chemical Properties ◽  
Neuse River Estuary ◽  
Estuarine System ◽  
Nutrient Loads ◽  
Habitat Alterations ◽  
The Past

<em>Abstract</em>.—Since the mid-1990s, the U.S. mid-Atlantic region has witnessed a sudden rise in hurricane and tropical storm landfalls. In particular, eastern North Carolina has been impacted by eight hurricanes and six tropical storms in the past decade, and this relatively high frequency is forecast to continue for the next several decades. Each of the past storms exhibited unique hydrologic and nutrient loading scenarios for the Pamlico Sound, the United States’ second largest estuarine system and its largest subestuary, the Neuse River estuary. This variability represents a challenge to nutrient management aimed at protecting water quality and ensuring optimal fisheries habitat conditions. Different rainfall amounts among hurricanes led to variable freshwater and nutrient discharge and hence variable nutrient, organic matter, and sediment enrichment. These enrichments differentially affected physical and chemical properties (salinity, water residence time, transparency, stratification, dissolved oxygen), phytoplankton primary production, and phytoplankton community composition. The contrasting effects were accompanied by biogeochemical perturbations (hypoxia, enhanced nutrient cycling), benthic and planktonic habitat alterations, and possibly food web disturbances. Floodwaters from the two largest hurricanes, Fran (1996) and Floyd (1999), exerted multimonth to multiannual effects on hydrology, nutrient loads, productivity, biotic composition, and habitat condition. In contrast, relatively low rainfall coastal hurricanes like Isabel (2003) and Ophelia (2005) caused strong vertical mixing and storm surges but exhibited relatively minor hydrologic, nutrient, and biotic impacts. Both hydrologic and wind forcing are important drivers and must be integrated with nutrient loading in assessing short- and long-term ecological impacts of these storms. These climatic forcings cannot be managed but must be considered when developing water quality management strategies for these and other large estuarine ecosystems faced with increasing frequencies and intensities of hurricane activity.

Historical Changes in Large River Fish Assemblages of the Americas

2005 ◽  
Keyword(s):  
Waste Treatment ◽  
Fish Assemblages ◽  
River System ◽  
Agricultural Runoff ◽  
Large River ◽  
Smallmouth Bass ◽  
Ohio River ◽  
Micropterus Dolomieu ◽  
Wabash River ◽  
Spotted Bass

<em>Abstract.</em>—The present ichthyofauna (1965–2001) of the Wabash River system is compared to that of three periods: presettlement through 1820, 1875–1900, and 1940– 1950. This second largest Ohio River tributary flows freely for 350 mi. However, its environment and watershed have been altered greatly from presettlement times; twothirds has been converted to agriculture, eliminating all prairies and most forests and wetlands. Canals, large and small dams, channelization, and effluents have extinguished 12 fish species, diminished some, and favored others. Thirteen of approximately 175 species are recent, including 3 aliens. Better municipal and industrial waste treatment has improved water quality, but excessive agricultural runoff remains detrimental to many fishes. Degraded habitats exacerbate these problems. Many sensitive species are today either absent or severely reduced in distribution and abundance compared to 50 years ago. Smallmouth bass <em>Micropterus dolomieu </em>has been replaced by largemouth bass <em>M. salmoides </em>or spotted bass <em>M. punctulatus, </em>and few visual piscivores occur except near reservoirs.

Correspondence Between Ecoregions and Spatial Patterns in Stream Ecosystems in Oregon

1988 ◽  
Vol 45 (7) ◽  
pp. 1264-1278 ◽  
Author(s):  
Thomas R. Whittier ◽  
Robert M. Hughes ◽  
David P. Larsen
Keyword(s):  
Water Quality ◽  
Fish Assemblages ◽  
Multivariate Analyses ◽  
Physical Habitat ◽  
Willamette Valley ◽  
Regional Patterns ◽  
Small Streams ◽  
Desert Regions ◽  
High Desert ◽  
Broad Scale

Multivariate analyses of biotic assemblages and physicochemical measures, species richness, diversity, and composition were used to evaluate the robustness of Omernik's ecoregion classification for small streams in the eight ecoregions of Oregon. Clearest differences were between the montane and nonmontane regions. For the three nonmontane regions, ordinations of fishes, macroinvertebrates, water quality, and physical habitat measures show the clearest differences, with the Willamette Valley ecoregion being consistently most unlike all other regions. Differences between the Columbia Basin and High Desert regions were clearest for water quality and physical habitat measures and fish assemblages. Differences among the montane regions were subtle. Of these regions, the East Cascade Slopes showed the greatest variability, as shown by the ranges of ordination scores for fishes, water quality, and physical habitat. Regional patterns in periphyton assemblages were markedly different from the patterns in the other groups of variables. Ecoregions can be used as a broad-scale geographic framework for classifying streams. This framework provides managers of lotic resources a useful alternative to river basins.

scholarly journals Water quality modeling of the Medellin river in the Aburrá Valley

DYNA ◽  
2015 ◽  
Vol 82 (192) ◽  
pp. 195-202
Author(s):  
Lina Claudia Giraldo Buitrago ◽  
Carlos Alberto Palacio ◽  
Rubén Darío Molina ◽  
Rubén Alberto Agudelo García
Keyword(s):  
Water Quality ◽  
Waste Treatment ◽  
Positive Impact ◽  
Treatment Plant ◽  
Water Quality Modeling ◽  
Low Flow ◽  
Critical Conditions ◽  
Quality Modeling ◽  
Waste Treatment Plant

Water quality modeling intends to represent a water body in order to assess their status and project the effects of different measures taken for their protection. This paper presents the results obtained from the Qual2kw model implementation in the first 50 kilometers of the Aburrá-Medellín River, in their most critical conditions of water quality, which correspond to low flow rates. After the model calibration, three recovery scenarios (short-term, medium-term and long-term) were evaluated. In the first scenario the sanitation only improved in some streams, in accordance with the Plan of Sanitation and Management of Discharges that was considered. Medium and long-term scenarios, with the operation of the new Water Waste Treatment Plant (WWTP) of the Bello municipality and an increase in the sewage collection, were considered. The obtained results show the positive impact of the operation of the WWTP of Bello in the balance of BOD5, dissolved oxygen and nitrogen.

The Effects of Improved Water Quality on Fish Assemblages in a Heavily Modified Large River System

2015 ◽  
Vol 32 (5) ◽  
pp. 992-1007 ◽  
Author(s):  
J. Parker ◽  
J. Epifanio ◽  
A. Casper ◽  
Y. Cao
Keyword(s):  
Water Quality ◽  
Fish Assemblages ◽  
River System ◽  
Large River
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