Changes in Fish Assemblages at the Mirror Lake Complex in the Lower Columbia River Before and After a Culvert Modification

To study the effects of a typhoon on a temperate, coastal bay community, the species composition, catch amount, and diversity of epipelagic fish assemblages were investigated. Fish samples were taken from catches of a purse seine fishery in Tachibana Bay, Japan between May and July 2011, covering before and after the passage of a typhoon in the area. Although major changes in total catch amount were not observed before and after the passage of the typhoon, the abundance of the Japanese anchovy, Engraulis japonicus Temminck et Schlegel, 1846, markedly decreased and bycatch of species increased, accompanied by increasing levels of diversity of the fish assemblage. Multivariate analysis showed that community differences before and after the passage were quantitative rather than qualitative. Comparisons in total length frequencies between the two periods indicated that specimens of the species compared were bigger in size for Trachurus japonicus (Temminck et Schlegel, 1844) and smaller for E. japonicus in the “after” period. These results suggest that the passage of the typhoon triggered not only interspecific faunal change but also intraspecific recruitment shifts in and around the bay.

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Can fishways restore river connectivity? A case study using β diversity as a method of assessment

Acta Limnologica Brasiliensia ◽

10.1590/s2179-975x13917 ◽

2018 ◽

Vol 30 (0) ◽

Cited By ~ 1

Author(s):

Hugo Marques ◽

João Henrique Pinheiro Dias ◽

Igor Paiva Ramos

Keyword(s):

Multidimensional Scaling ◽

Fish Assemblages ◽

Neotropical Fish ◽

Whitney Test ◽

Β Diversity ◽

Mantel Tests ◽

Before And After ◽

Method Of Assessment ◽

Sørensen Index

Abstract Aim β diversity was used as an indicator to test the hypothesis that a fishway can increase river connectivity, as a reduction in the value of this metric indicates greater similarity among fish assemblages. Methods Quarterly sampling was performed with gillnets upstream and downstream of the Porto Primavera dam, Upper Paraná Basin, before the opening of the fishway between February 1999 and May 2001, and between February 2003 and May 2005 with the fishway in operation (10 samples per period/site). The correlation between the fish assemblages and sites was verified by applying two Mantel tests (downstream versus upstream before and one equivalent after the fishway) using the distance matrices generated by the Bray‐Curtis index. The β diversity between downstream and upstream was calculated using the Sørensen index for each sample for the comparison of such values before and after the operation of the fishway, which were tested with Asymptotic Wilcoxon-Mann-Whitney Test. To summarize changes in the structure of the fish assemblages between the sites and periods nonmetric multidimensional scaling (NMDS) was applied based on Bray-Curtis dissimilarities, using multi-response permutation procedures (MRPP). Results The Mantel tests showed no correlation between the upstream and downstream assemblages before the operation of the fishway but greater correlation after. β diversity was lower after than before the fishway, representing an increase in similarity between downstream and upstream with the fishway. MRPP analysis indicated that the fish assemblages between the sites differed more than was expected by chance, with smaller divergence between the sampling sites after the fishway (A = 0.08) than before it opened (A = 0.09). Conclusions Although fishways remain an incipient and controversial theme for neotropical fish, the Porto Primavera fishway appears to be effective in terms of the restoration of connectivity.

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Hanford and Columbia River Basin Basalts: x-ray characterization before and after hydrothermal treatment

10.2172/6881266 ◽

1978 ◽

Author(s):

M. Barnes

Keyword(s):

Hydrothermal Treatment ◽

River Basin ◽

Columbia River ◽

Columbia River Basin ◽

X Ray ◽

Before And After

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Life history variation in upper Columbia River Chinook salmon (Oncorhynchus tshawytscha): a comparison using modern and ~500-year-old archaeological otoliths

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f2011-002 ◽

2011 ◽

Vol 68 (4) ◽

pp. 603-617 ◽

Cited By ~ 26

Author(s):

Jessica A. Miller ◽

Virginia L. Butler ◽

Charles A. Simenstad ◽

David H. Backus ◽

Adam J.R. Kent

Keyword(s):

Life History ◽

Chinook Salmon ◽

Life Histories ◽

Oncorhynchus Tshawytscha ◽

Columbia River ◽

Adult Size ◽

Limited Information ◽

Life History Variation ◽

Archaeological Collections ◽

Before And After

Conservation planning often occurs only after a species has been extirpated from portions of its historical range and limited information is available on life history diversity prior to development. To provide information on Chinook salmon ( Oncorhynchus tshawytscha ) life history before and after local extirpation, we examined the chemical (87Sr:86Sr, Sr:Ca) and structural composition of modern and archaeological otoliths from the upper Columbia River. We compared otoliths from modern spring (yearling migrant, n = 15) and summer–fall (yearling (n = 7) and subyearling (n = 12) migrants) runs with those from extirpated runs (n = 8) to estimate the number of and similarity among natal environments and reconstruct aspects of the migratory history. Presumptive natal sources were most similar between the archaeological collections and the modern summer–fall run. Chinook salmon represented by the archaeological otoliths also displayed life history traits, including size at freshwater emigration and adult size at return to fresh water, most similar to the summer–fall subyearling run. These data indicate that there is the potential to maintain aspects of predevelopment Chinook salmon life histories in the Columbia River, and strategies that promote maintenance of that life history diversity may be warranted.

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Historical Changes in Large River Fish Assemblages of the Americas

Historical Changes in Large River Fish Assemblages of the Americas ◽

10.47886/9781888569728.ch21 ◽

2005 ◽

Keyword(s):

Water Pollution ◽

Best Management Practices ◽

Fish Assemblage ◽

Municipal Wastewater ◽

Fish Assemblages ◽

Primary Objective ◽

Nonpoint Sources ◽

Control Programs ◽

Before And After ◽

River Fish

<em>Abstract.</em>—A systematic, standardized approach to monitor fish assemblages has been applied in Ohio’s rivers since 1979. A primary objective is the assessment of changes in response to water pollution abatement and other water quality management programs. All major, nonwadeable rivers were intensively sampled using standardized electrofishing methods and a summer–early fall index period. Most rivers were sampled two or three times, before and after implementation of pollution controls at major point source discharges and best management practices for nonpoint sources. A modified and calibrated index of biotic integrity (IBI) was used to demonstrate and evaluate changes at multiple sampling locations in major river segments. An area of degradation value (ADV) and an area of attainment value (AAV) were also calculated from IBI results to demonstrate the magnitude and extent of changes in fish assemblage condition along segments and between sampling years. Positive responses in the IBI and the ADV/AAV were observed 4 to 5 years after implementing improved municipal wastewater treatment. Positive responses were much less apparent in rivers predominantly influenced by complex industrial sources, agricultural nonpoint sources, and extensive hydrologic modifications. The ADV/AAV showed incremental improvements in river fish assemblages, unlike pass/fail IBI thresholds, and tiered IBI biocriteria provided more appropriate benchmarks than chemical, physical, or qualitative biological criteria. The results show the value of standardized and intensive fish assemblage monitoring and the use of tools that reveal the extent and severity of impairments to determine the effectiveness of water pollution control programs.

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Impacts of low-head hydropower plants on cyprinid-dominated fish assemblages in Lithuanian rivers

Scientific Reports ◽

10.1038/s41598-020-78701-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Tomas Virbickas ◽

Paolo Vezza ◽

Jūratė Kriaučiūnienė ◽

Vytautas Akstinas ◽

Diana Šarauskienė ◽

...

Keyword(s):

Relative Abundance ◽

Fish Species ◽

Fish Assemblages ◽

Rutilus Rutilus ◽

Environmental Flow ◽

Low Flow ◽

Exceedance Probability ◽

Hydropower Plants ◽

Before And After ◽

Low Head

AbstractThe meso-scale habitat simulation model MesoHABSIM was applied in three Lithuanian lowland rivers to study the effect of low-head hydropower plants (HPPs) on the fish habitats. Stream flow time series on a daily scale for the period 1970–2015 were used to describe flow regime downstream of HPPs for periods before and after their installation. Conditional habitat suitability criteria were developed for 4 species of cyprinid fish, schneider (Alburnoides bipunctatus), dace (Leuciscus leuciscus), roach (Rutilus rutilus) and vimba (Vimba vimba) to simulate their available habitat at different water discharges. Modelling results showed that HPPs have a significant impact on habitat availability in the low flow period in dry years below HPPs due to insufficient released flow. The environmental flow, as prescribed by the Lithuanian national law, is estimated between 80 and 95% exceedance probability of the mean minimum discharge of 30 days. This flow leads to a significant reduction in frequency and duration of available suitable habitats for vimba and schneider during low flow period. The roach habitat is the least affected. The results of habitat modelling are in line with the actual data on the occurrence and relative abundance of considered fish species in the studied river stretches. A general comparison of the relative abundance of modelled fish species in 42 natural river stretches and 20 stretches below the HPPs also showed that the relative abundance of roach is significantly higher, and that of schneider is significantly lower in river sections below the HPPs than the abundance in natural river sections. All results indicate that the current environmental flow does not secure survival of certain fish species. The applicability of the average low flow release during summer could be a plausible alternative to the current environmental flow in order to maintain ecosystem health and services.

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