scholarly journals The importance of a constructed near-nature-like Danube fish by-pass as a lifecycle fish habitat for spawning, nurseries, growing and feeding: a long-term view with remarks on management

2018 ◽  
Vol 69 (12) ◽  
pp. 1857 ◽  
Author(s):  
Paul Meulenbroek ◽  
Silke Drexler ◽  
Christoffer Nagel ◽  
Michael Geistler ◽  
Herwig Waidbacher
Keyword(s):  
Fish Habitat ◽  
Fish Fauna ◽  
Native Fish ◽  
Management Tools ◽  
Pass System ◽  
Barbus Barbus ◽  
Danube Catchment ◽  
Chondrostoma Nasus ◽  
Riverine Fish

Major sections of today’s rivers are man made and do not provide the essential requirements for riverine fish. A nature-like fish by-pass system in Vienna-Freudenau was assessed for its function as a fish habitat. The study was conducted continuously over 3 years; 15 years after construction of the by-pass. The chosen nature-like construction of the by-pass system functions like natural tributaries. More than 17000 fish and 43 species, including several protected and endangered species, in all life stages, including eggs, larvae, juveniles and adults, were captured. Furthermore, the indicator species of the free-flowing Danube, nase (Chondrostoma nasus) and barbel (Barbus barbus), migrated into the fish by-pass and successfully spawned before returning. Therefore, our results suggest that by-pass systems can function as an important habitat for the conservation of native fish fauna. The heterogenic habitat configuration provides conditions for all ecological guilds and, consequently, increases biodiversity. Finally, approved management tools are discussed. We suggest that fish by-pass channels may be suitable at other sites in the Danube catchment.

scholarly journals Comparison of ovarian cycles of Hungarian riverine fish species representing different spawning strategies 441

2008 ◽  
Vol 53 (No. 10) ◽  
pp. 441-452 ◽  
Author(s):  
K.K. Lefler ◽  
Á. Hegyi ◽  
F. Baska ◽  
J. Gál ◽  
Á. Horváth ◽  
...  
Keyword(s):  
Fish Species ◽  
Ovarian Cycle ◽  
Spawning Period ◽  
Barbus Barbus ◽  
Chondrostoma Nasus ◽  
Leuciscus Idus ◽  
Riverine Fish ◽  
White Bream ◽  
Heterogeneous Size

Investigations on the ovarian cycle of fish species that inhabit Hungarian rivers are necessitated by both environmental and economic reasons. The objective of our research was to explore new fundamental knowledge concerning the ovarian cycle of the white bream (<I>Blicca bjoerkna</I>, Linnaeus, 1758), barbel (<I>Barbus barbus</I>, Linnaeus, 1758), orfe <I>(Leuciscus idus</I>, Linnaeus, 1758) and nase (<I>Chondrostoma nasus</I>, Linnaeus, 1758). Histological investigation of ovaries and determination of proportions of oocytes in different stages of development is an appropriate method for the description of spawning characteristics of these species. Our results show that the GSI value for all four investigated species starts to increase at the end of summer and reaches its maximum before spawning. In the barbel and white bream, the presence of oocytes in the stage of cortical alveoli and the heterogeneous size of oocytes in the stage of vitellogenesis in the pre-spawning period indicate that barbel and white bream are multiple spawners. In contrast, in the orfe and nase, the absence of oocytes in the stage of cortical alveoli and the homogeneous size of cells in the stage of vitellogenesis indicate that orfe and nase are single spawners.

scholarly journals Predicting New Zealand riverine fish reference assemblages

2018 ◽  
Author(s):  
Adam D Canning
Keyword(s):  
New Zealand ◽  
Freshwater Fish ◽  
Riparian Vegetation ◽  
Fish Assemblages ◽  
Reference Conditions ◽  
Native Fish ◽  
River Reach ◽  
Riverine Fish ◽  
Insight Into

Biomonitoring is a common method to monitor environmental change in river ecosystems, a key advantage of biomonitoring over snap-shot physicochemical monitoring is that it provides a more stable, long-term. insight into change that is also effects-based. In New Zealand, the main biomonitoring method is a macroinvertebrate sensitivity scoring index, with little established methods available for biomonitoring of fish. This study models the contemporary distribution of common freshwater fish and then uses those models to predict freshwater fish assemblages for each river reach under reference conditions. Comparison of current fish assemblages with those predicted in reference conditions (as observed/expected ratios) may provide a suitable option for freshwater fish biomonitoring. Most of the fish communities throughout the central North Island and lower reaches show substantial deviation from the modelled reference community. Most of this deviation is explained by nutrient enrichment, followed by downstream barriers (i.e., dams) and loss of riparian vegetation. The presence of modelled introduced species had relatively little on the presence of the modelled native fish. The maps of observed/expected fish assemblage may provide a rapid way to identify potential restoration sites.

scholarly journals The Contribution of Different Restored Habitats to Fish Diversity and Population Development in a Highly Modified River: A Case Study from the River Günz

Water ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1202 ◽  
Author(s):  
Joachim Pander ◽  
Juergen Geist
Keyword(s):  
Habitat Restoration ◽  
Fish Diversity ◽  
Population Development ◽  
Target Species ◽  
Endangered Fish ◽  
Barbus Barbus ◽  
High Conservation ◽  
Chondrostoma Nasus ◽  
River Dynamic ◽  
Riverine Fish

Despite of structural deficits, highly modified water bodies (HMWB) contain remnant populations of endangered fish that have high conservation value. Restoration in HMWBs underlies different principles when compared to natural rivers because of impaired river dynamic processes. The objective herein was to assess the contribution of restored habitats of the River Günz, Germany to fish diversity and restoration success of target species. All habitat restoration types, including bank habitats, fast flowing habitats with gravel, structured shallow water zones, nature like fish passes, and a former river course below a spillway were assessed. None of them comprised the full set of 27 fish species or size classes, indicating that the diversity and interlinkage of the restored habitats is most crucial to sustainable fish populations and high biodiversity. When considering the rheophilic target species Chondrostoma nasus and Barbus barbus, only fish passes and the former river course with their high flow current contributed much to their population development, particularly to young specimens <20 cm. The results of this study indicate that measures inside the main channel are unlikely to mitigate deficiencies in HMWBs concerning specialized riverine fish. Instead, interlinkage of a diversity of restoration measures and investment of resources for restoration in HMWBs into nature-like fish passes or former river courses below spillways with dynamically managed discharges seem most useful.

scholarly journals Predicting New Zealand riverine fish reference assemblages

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4890 ◽  
Author(s):  
Adam D. Canning
Keyword(s):  
New Zealand ◽  
Freshwater Fish ◽  
Riparian Vegetation ◽  
Fish Assemblages ◽  
Reference Conditions ◽  
Native Fish ◽  
River Reach ◽  
Riverine Fish ◽  
Insight Into

Biomonitoring is a common method to monitor environmental change in river ecosystems, a key advantage of biomonitoring over snap-shot physicochemical monitoring is that it provides a more stable, long-term insight into change that is also effects-based. In New Zealand, the main biomonitoring method is a macroinvertebrate sensitivity scoring index, with little established methods available for biomonitoring of fish. This study models the contemporary distribution of common freshwater fish and then uses those models to predict freshwater fish assemblages for each river reach under reference conditions. Comparison of current fish assemblages with those predicted in reference conditions (as observed/expected (O/E) ratios) may provide a suitable option for freshwater fish biomonitoring. Most of the fish communities throughout the central North Island and lower reaches show substantial deviation from the modelled reference community. Most of this deviation is explained by nutrient enrichment, followed by downstream barriers (i.e. dams) and loss of riparian vegetation. The presence of modelled introduced species had relatively little impact on the presence of the modelled native fish. The maps of O/E fish assemblage may provide a rapid way to identify potential restoration sites.

scholarly journals Predicting New Zealand riverine fish reference assemblages

2018 ◽  
Author(s):  
Adam D Canning
Keyword(s):  
New Zealand ◽  
Freshwater Fish ◽  
Riparian Vegetation ◽  
Fish Assemblages ◽  
Reference Conditions ◽  
Native Fish ◽  
River Reach ◽  
Riverine Fish ◽  
Insight Into

Biomonitoring is a common method to monitor environmental change in river ecosystems, a key advantage of biomonitoring over snap-shot physicochemical monitoring is that it provides a more stable, long-term. insight into change that is also effects-based. In New Zealand, the main biomonitoring method is a macroinvertebrate sensitivity scoring index, with little established methods available for biomonitoring of fish. This study models the contemporary distribution of common freshwater fish and then uses those models to predict freshwater fish assemblages for each river reach under reference conditions. Comparison of current fish assemblages with those predicted in reference conditions (as observed/expected ratios) may provide a suitable option for freshwater fish biomonitoring. Most of the fish communities throughout the central North Island and lower reaches show substantial deviation from the modelled reference community. Most of this deviation is explained by nutrient enrichment, followed by downstream barriers (i.e., dams) and loss of riparian vegetation. The presence of modelled introduced species had relatively little on the presence of the modelled native fish. The maps of observed/expected fish assemblage may provide a rapid way to identify potential restoration sites.

scholarly journals Advancing improvement in riverine water quality caused a non-native fish species invasion and native fish fauna recovery

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Łukasz Głowacki ◽  
Andrzej Kruk ◽  
Tadeusz Penczak
Keyword(s):  
Water Quality ◽  
Fish Species ◽  
Native Species ◽  
Interference Competition ◽  
Fish Fauna ◽  
Species Traits ◽  
Native Fish ◽  
Biological Degradation ◽  
Species Invasion ◽  
Prussian Carp

AbstractThe knowledge of biotic and abiotic drivers that put non-native invasive fishes at a disadvantage to native ones is necessary for suppressing invasions, but the knowledge is scarce, particularly when abiotic changes are fast. In this study, we increased this knowledge by an analysis of the biomass of most harmful Prussian carp Carassius gibelio in a river reviving from biological degradation. The species' invasion followed by the invasion's reversal occurred over only two decades and were documented by frequent monitoring of fish biomass and water quality. An initial moderate improvement in water quality was an environmental filter that enabled Prussian carp’s invasion but prevented the expansion of other species. A later substantial improvement stimulated native species’ colonization of the river, and made one rheophil, ide Leuciscus idus, a significant Prussian carp’s replacer. The redundancy analysis (RDA) of the dependence of changes in the biomass of fish species on water quality factors indicated that Prussian carp and ide responded in a significantly opposite way to changes in water quality in the river over the study period. However, the dependence of Prussian carp biomass on ide biomass, as indicated by regression analysis and analysis of species traits, suggests that the ecomorphological similarity of both species might have produced interference competition that contributed to Prussian carp’s decline.

Large-scale patterns in species richness and composition of temperate riverine fish communities, south-eastern Australia

2000 ◽  
Vol 51 (2) ◽  
pp. 165 ◽  
Author(s):  
Peter C. Gehrke ◽  
John H. Harris
Keyword(s):  
Species Richness ◽  
Large Scale ◽  
Fish Communities ◽  
Fish Fauna ◽  
South Coast ◽  
North Coast ◽  
Large Spatial Scale ◽  
River Types ◽  
Eastern Australia ◽  
Riverine Fish

Riverine fish in New South Wales were studied to examine longitudinal trends in species richness and to identify fish communities on a large spatial scale. Five replicate rivers of four types (montane, slopes, regulated lowland and unregulated lowland) were selected from North Coast, South Coast, Murray and Darling regions. Fishwere sampled during summer and winter in two consecutive years with standardized gear that maximized the range of species caught. The composition of fish communities varied among regions and river types, with little temporal variation. Distinct regional communities converged in montane reaches and diverged downstream. The fish fauna can be classified into North Coast, South Coast, Murray and Darling communities, with a distinct montane community at high elevations irrespective of the drainage division. Species richness increased downstream in both North Coast and South Coast regions by both replacement and the addition of new species. In contrast, species richness in the Darling and Murray regions reached a maximum in the slopes reaches and then declined, reflecting a loss of species in lowland reaches. The small number of species is typical of the freshwater fish faunas of similar climatic regions world-wide. Fish communities identified in this study form logical entities for fisheries management consistent with the ecosystem-focused, catchment-based approach to river management and water reform being adopted in Australia.

scholarly journals Typology of historical sources and the reconstruction of long‐term historical changes of riverine fish: a case study of the A ustrian D anube and northern R ussian rivers

2013 ◽  
Vol 23 (4) ◽  
pp. 498-515 ◽  
Author(s):  
Gertrud Haidvogl ◽  
Dmitry Lajus ◽  
Didier Pont ◽  
Martin Schmid ◽  
Mathias Jungwirth ◽  
...  
Keyword(s):  
Historical Sources ◽  
Historical Changes ◽  
Riverine Fish

Relationships between riverine fish and woody debris: implications for lowland rivers

1999 ◽  
Author(s):  
D. A. Crook ◽  
A. I. Robertson
Keyword(s):  
Woody Debris ◽  
Fish Habitat ◽  
Reference Points ◽  
Positive Development ◽  
Lowland River ◽  
Predator Prey ◽  
Lowland Rivers ◽  
Habitat Features ◽  
Surface Areas ◽  
Riverine Fish

This paper reviews studies of relationships between riverine fish and woody debris at micro- and meso-habitat scales, and discusses the potential functions of instream structure for lowland river fish. Experimental research, mainly in North America, has identified three main functions of woody debris as microhabitat for fish in upland streams: overhead cover that decreases predation risk both vertically and horizontally; horizontal visual isolation that reduces contact between fish; and velocity refuge which minimizes energetic costs. As with habitat features in other aquatic environments, increasing spatial complexity of woody debris may modify predator–prey interactions and provide greater surface areas for the growth of prey items. Woody debris may also provide spatial reference points for riverine fish to assist them in orienting within their surroundings. Lowland rivers differ from upland streams in terms of a number of physical variables, including turbidity, depth and water turbulence. Relationships between fish and woody debris in lowland rivers are likely to rely on mechanisms different to those in upland streams. Recent initiatives involving the reintroduction of woody debris into previously cleared lowland rivers to replace lost fish habitat are a positive development for lowland river restoration. However, if woody debris reintroduction is to maximally benefit lowland river fisheries, there is a requirement for better understanding of the ecological functions of woody debris in lowland rivers.

scholarly journals Identifying Project Corporate Behavioral Risks to Support Long-Term Sustainable Cooperative Partnerships

2021 ◽  
Vol 13 (11) ◽  
pp. 6347
Author(s):  
Marco Nunes ◽  
António Abreu ◽  
Célia Saraiva
Keyword(s):  
Social Network ◽  
Project Management ◽  
Social Network Analysis ◽  
Network Analysis ◽  
Building Blocks ◽  
Research Literature ◽  
Management Tools ◽  
Dynamic Interactions ◽  
Major Factors

Projects are considered crucial building blocks whereby organizations execute and implement their short-, mid-, and long-term strategic visions. Projects are thought, developed, and implemented to solve problems, drive change, satisfy unique needs, add value, and exploit opportunities, just to name a few objectives. Although existing project management tools and techniques aim to deliver projects with success, according to the latest reviewed literature, projects still keep failing at an impressive pace. Among the extensive list of factors that may threaten project success, several articles from the research literature place particular importance on a still underexplored factor that may strongly lead to unsuccessful project delivery. This factor—usually known as corporate behavioral risks—usually emerges and evolves as organizations work together to deliver projects across a bounded period of time, and is characterized by the mix of formal and informal dynamic interactions between the different stakeholders that constitute the different organizations. Furthermore, several articles from the research literature also point out the lack of proper models to efficiently manage corporate behavioral risks as one of the major factors that may lead to projects failing. To efficiently identify and measure how such corporate behaviors may contribute to a project’s outcomes (success or failure), a heuristic model is proposed in this work, developed based on four fundamental fields ((1) project management, (2) risk management, (3) corporate behavior, and (4) social network analysis), to quantitatively analyze four critical project social networks ((1) communication, (2) problem-solving, (3) advice, and (4) trust), by applying the theory of social network analysis (SNA). The proposed model in this work is supported with a case study to illustrate its implementation and application across a project lifecycle, and how organizations can benefit from its application.

Sign in / Sign up

Export Citation Format

Share Document