Migration patterns and estuarine aggregations of a catadromous fish, Australian bass (Percalates novemaculeata) in a regulated river system

2017 ◽  
Vol 68 (8) ◽  
pp. 1544 ◽  
Author(s):  
D. J. Harding ◽  
R. G. Dwyer ◽  
T. M. Mullins ◽  
M. J. Kennard ◽  
R. D. Pillans ◽  
...  
Keyword(s):  
Fish Species ◽  
Large Scale ◽  
River System ◽  
Regulated River ◽  
Regulated Rivers ◽  
Migration Patterns ◽  
Migratory Response ◽  
Resource Managers ◽  
Receiver Array ◽  
Downstream Movement

Catadromous fish species require adequate flows to migrate between fresh and saltwater habitats to reproduce. However, artificial barriers and flow alteration affect fish populations by reducing habitat connectivity and disrupting movement cues. In regulated rivers, it is critical that migratory flow requirements are quantified to optimise water allocation for multiple users. In the present study, we assessed the migratory timing, flow and estuarine aggregation requirements for Australian bass (Percalates novemaculeata). Over 2 years, 66 bass were tracked using an acoustic receiver array in the Logan River (Qld, Australia). Bass performed large-scale downstream movements in response to elevated winter flows (40 and 108m3 s–1), which facilitated migration to the lower estuary, where salinity conditions were appropriate for spawning. Bass migrations occurred only when gonads were mature, despite large flows providing opportunities for movement outside this period. Experimental flow releases from an impoundment (2.1m3 s–1) during winter did not elicit a migratory response. Connectivity between upstream and estuarine habitats was reduced by the presence of instream weirs, with downstream movement across weirs occurring only when sufficient flow magnitude was achieved (>76.1m3 s–1). These findings are relevant for water resource managers formulating environmental flow rules for catadromous fish species in systems with multiple instream artificial barriers.

scholarly journals Isolating causal pathways between flow and fish in the regulated river hierarchy

2015 ◽  
Vol 72 (11) ◽  
pp. 1731-1748 ◽  
Author(s):  
Ryan A. McManamay ◽  
Brandon K. Peoples ◽  
Donald J. Orth ◽  
Charles A. Dolloff ◽  
David C. Matthews
Keyword(s):  
Structural Equation ◽  
Large Scale ◽  
Fish Assemblages ◽  
Causal Structure ◽  
River Regulation ◽  
Regulated River ◽  
Equation Modeling ◽  
Regulated Rivers ◽  
Causal Pathways ◽  
The Hierarchical Structure

Unregulated river systems are organized in a hierarchy in which large-scale factors (i.e., landscape and segment scales) influence local habitats (i.e., reach, meso-, and microhabitat scales), and both differentially exert selective pressures on biota. Dams, however, create discontinua in these processes and change the hierarchical structure. We examined the relative roles of hydrology and other instream factors, within a hierarchical landscape context, in organizing fish communities in regulated and unregulated tributaries to the Upper Tennessee River, USA. We used multivariate regression trees to identify factors that partition fish assemblages based on trait similarities, irrespective of spatial scale. We then used classical path analysis and structural equation modeling to evaluate the most plausible hierarchical causal structure of specific trait-based community components, given the data. Both statistical approaches suggested that river regulation affects stream fishes through a variety of reach-scale variables, not always through hydrology itself. Although we observed different changes in flow, temperature, and biotic responses according to regulation types, the most predominant path in which dam regulation affected biota was via temperature alterations. Diversion dams had the strongest effects on fish assemblages. Diversion dams reduced flow magnitudes, leading to declines in fish richness but increased temperatures, leading to lower abundances in equilibrium species and nest guarders. Peaking and run-of-river dams increased flow variability, leading to lower abundances in nest-guarding fishes. Flow displayed direct relationships with biotic responses; however, results indicated that changes in temperature and substrate had equal, if not stronger, effects on fish assemblage composition. The strength and nature of relationships depended on whether flow metrics were standardized for river size. We suggest that restoration efforts in regulated rivers focus on improving flow conditions in conjunction with temperature and substrate restoration.

scholarly journals Assessment and ranking flood events in a regulated river using information and complexity measures

2021 ◽  
Vol 2090 (1) ◽  
pp. 012169
Author(s):  
Mohamad Basel Al Sawaf ◽  
Kiyosi Kawanisi ◽  
Cong Xiao
Keyword(s):  
Risk Control ◽  
River System ◽  
River Regulation ◽  
Environmental Risks ◽  
Regulated River ◽  
Flood Events ◽  
Regulated Rivers ◽  
Complexity Measures ◽  
Complexity Metrics

Abstract The availability of a robust approach that describe the hidden features of flood events in regulated rivers is of great importance. The key goal of this research is to utilize some of information and complexity measures to assess and rank flood patterns within a regulated river system. To meet this goal, the Metric Entropy (ME) as measure of information content and Rényi Complexity (CR) as a quantification for complexity content were employed. To examine the role of river regulation on flood risk control, river stage records of two monitoring stations located at downstream of two different dams were considered in this research. The findings show that information and complexity metrics offer an image of the randomness embedded in dataset and the presence of internal patterns in studied data records. In general, this research shows that natural environmental risks and disasters can be assessed and ranked using a promising physical scheme based on information and complexity measures.

Can tributary in-flows improve the recovery of the dissolved organic carbon regime in a snowmelt river regulated by a large reservoir?

2016 ◽  
Vol 67 (9) ◽  
pp. 1338 ◽  
Author(s):  
Ann-Marie Rohlfs ◽  
Simon M. Mitrovic ◽  
Simon Williams ◽  
Daniel Coleman
Keyword(s):  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
River System ◽  
Main Stem ◽  
Water Diversion ◽  
Regulated River ◽  
Regulated Rivers ◽  
Large Reservoir ◽  
Doc Export ◽  
Doc Concentration

Although tributary inputs can accelerate the recovery of many physical and chemical gradients below large reservoirs, their contribution to the dissolved organic carbon (DOC) regime in regulated rivers remains poorly studied. In some regulated tributaries, flow volumes can be manipulated, potentially influencing DOC supply to the main stem. The present study examines how tributary water diversion affects DOC supply to a snowmelt river regulated by large reservoirs. DOC concentration was measured at tributary and main stem sites, and tributary DOC export was estimated under different tributary flow-diversion scenarios. Significant, positive correlations between DOC concentration and discharge were absent directly below the dam, but were present in the unregulated tributary, and re-emerged below the tributary confluence. Irrespective of water-diversion practices, tributary in-flows reconnected the regulated main stem to a more variable DOC regime driven by catchment flushing processes. However, tributary water diversion dampened the tributary signal by reducing DOC pulse frequency and total DOC export to the regulated river. These aspects of the DOC regime may influence basal resource availability and ecosystem functioning in the regulated main stem. The present study illustrates how an ecologically valuable tributary function can be addressed and quantified to guide the management and rehabilitation of a regulated river system.

scholarly journals Streamflow predictions in regulated river systems: hydrological non-stationarity versus anthropogenic water use

2015 ◽  
Vol 371 ◽  
pp. 35-42 ◽  
Author(s):  
D. Dutta ◽  
S. Kim ◽  
J. Vaze ◽  
J. Hughes
Keyword(s):  
Climate Variability ◽  
Water Use ◽  
Large Scale ◽  
River System ◽  
System Model ◽  
Regulated River ◽  
Irrigated Agriculture ◽  
Anthropogenic Development ◽  
Streamflow Variability ◽  
Water Uses

Abstract. Streamflow in a regulated river system is highly influenced by storage regulations and anthropogenic water use in addition to climate variability. Thus, changes in climate-streamflow relationships and dominant hydrological processes over time are difficult to quantify in a regulated system without partitioning influence of storage regulation and anthropogenic water uses. This requires a robust regulated river system model, which takes into consideration of both hydrological and man-made flow regulation processes, as well as anthropogenic water uses. In this study, a newly developed large-scale river system model (called "AWRA-R") was used to assess the influence of both anthropogenic and climate variability/change on streamflow non-stationarity in the Murray Darling Basin (MDB). MDB is one of the highly regulated basins in Australia with multiple large and small storages developed primarily for supplying water to irrigated agriculture. The modelling was undertaken for the period of 1950–2010, which includes rapid water resources development and both wet and dry climate. The AWRA-R model was calibrated for a reasonably long period and then, validated on an independent period. The calibrated parameters were used to simulate streamflow under current and pre-development conditions to analyse the streamflow variability and influence of climate variability and anthropogenic development on streamflow trend. This paper briefly introduces the model and the method used for assessing streamflow variability under natural and developed conditions and presents the results and findings.

Flow-related migration, juvenile dispersal and gonad development in two co-occurring mullet species, Mugil cephalus and Trachystoma petardi, in a regulated river system

2019 ◽  
Vol 70 (8) ◽  
pp. 1105 ◽  
Author(s):  
D. J. Harding ◽  
D. T. Roberts ◽  
D. Sternberg ◽  
T. M. Mullins ◽  
M. J. Kennard ◽  
...  
Keyword(s):  
Large Scale ◽  
Gonad Development ◽  
Movement Ecology ◽  
River System ◽  
Fish Passage ◽  
Mugil Cephalus ◽  
Regulated River ◽  
Pit Tags ◽  
Juvenile Dispersal ◽  
Eastern Australia

Catadromous fish species often use elevated flows to migrate from freshwater to downstream spawning grounds. However, in regulated river systems, artificial barriers and flow alteration can disrupt movement cues, affecting fish migration. Using a combination of acoustic telemetry, passive integrated transponder (PIT) tags and gonad maturity data, we assessed the migratory timing and flow requirements for downstream spawning migrations and upstream dispersal in two co-occurring mullet species in the Logan River, eastern Australia. Over 4 years, 141 adult sea mullet (Mugil cephalus) and 28 adult pinkeye mullet (Trachystoma petardi) were implanted with acoustic transmitters and broad-scale movements tracked using an array of 49 acoustic receivers. Juvenile upstream dispersal was monitored using implanted PIT tags and readers deployed in weir fishways. Sea mullet and pinkeye mullet undertook large-scale downstream migrations from February to March. Movements past weirs only occurred once sufficient flow had occurred and, in the case of pinkeye mullet, when gonads were mature. In contrast, juvenile dispersal into upstream habitats occurred primarily between November and April on low flows. This study advances our understanding of bidirectional movement ecology and flow requirements of two co-occurring mullet species to inform environmental flow management (e.g. to facilitate fish passage) in a regulated river system.

scholarly journals Hydrology influences breeding time in the white-throated dipper

BMC Ecology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Anna L. K. Nilsson ◽  
Thomas Skaugen ◽  
Trond Reitan ◽  
Jan Henning L’Abée-Lund ◽  
Marlène Gamelon ◽  
...  
Keyword(s):  
Climate Change ◽  
River Discharge ◽  
Large Scale ◽  
Time Window ◽  
River System ◽  
Open Water ◽  
Local Conditions ◽  
Environmental Indices ◽  
Groundwater Levels ◽  
Breeding Time

Abstract Background Earlier breeding is one of the strongest responses to global change in birds and is a key factor determining reproductive success. In most studies of climate effects, the focus has been on large-scale environmental indices or temperature averaged over large geographical areas, neglecting that animals are affected by the local conditions in their home ranges. In riverine ecosystems, climate change is altering the flow regime, in addition to changes resulting from the increasing demand for renewable and clean hydropower. Together with increasing temperatures, this can lead to shifts in the time window available for successful breeding of birds associated with the riverine habitat. Here, we investigated specifically how the environmental conditions at the territory level influence timing of breeding in a passerine bird with an aquatic lifestyle, the white-throated dipper Cinclus cinclus. We relate daily river discharge and other important hydrological parameters, to a long-term dataset of breeding phenology (1978–2015) in a natural river system. Results Dippers bred earlier when winter river discharge and groundwater levels in the weeks prior to breeding were high, and when there was little snow in the catchment area. Breeding was also earlier at lower altitudes, although the effect dramatically declined over the period. This suggests that territories at higher altitudes had more open water in winter later in the study period, which permitted early breeding also here. Unexpectedly, the largest effect inducing earlier breeding time was territory river discharge during the winter months and not immediately prior to breeding. The territory river discharge also increased during the study period. Conclusions The observed earlier breeding can thus be interpreted as a response to climate change. Measuring environmental variation at the scale of the territory thus provides detailed information about the interactions between organisms and the abiotic environment.

Performance of a pool-and-weir fish pass for small bottom-dwelling freshwater fish species in a regulated lowland river

2007 ◽  
Vol 57 (4) ◽  
pp. 423-432 ◽  
Author(s):  
Evelien Maerten ◽  
Marcel Eens ◽  
Guy Knaepkens
Keyword(s):  
Freshwater Fish ◽  
Fish Species ◽  
Fish Assemblages ◽  
Regulated River ◽  
Lowland River ◽  
Stone Loach ◽  
Spined Loach ◽  
Freshwater Fish Species ◽  
Cottus Gobio ◽  
Fish Pass

AbstractAlthough small benthic freshwater fish species are an important biological component of fish assemblages and free instream movement is indispensable for their survival, they are often neglected in fish pass performance studies. In this study, a capture-mark-recapture approach was used to assess whether small bottom-dwelling species, including gudgeon (Gobio gobio), stone loach (Barbatula barbatula), spined loach (Cobitis taenia) and bullhead (Cottus gobio), were able to cross a pool-and-weir fish pass in a regulated lowland river. Some tagged individuals of stone loach (18%), gudgeon (7%) and spined loach (2%) managed to successfully ascend the fish pass under study, despite the fact that water velocity levels in the different overflows of the facility (between 0.55-1.22 m/s) exceeded the critical swimming speed of all three species. Although this suggests that a pool-and-weir fish pass is a able to facilitate upstream movement of some small benthic species in a regulated river, more detailed research incorporating advanced tagging and retrieving techniques is necessary.

Automated monitoring of a large-scale cod (Gadus morhua) migration in the open sea

2002 ◽  
Vol 59 (12) ◽  
pp. 1845-1850 ◽  
Author(s):  
Luc A Comeau ◽  
Steven E Campana ◽  
Martin Castonguay
Keyword(s):  
Large Scale ◽  
Gadus Morhua ◽  
Atlantic Cod ◽  
Seasonal Migration ◽  
Migration Routes ◽  
Eastern Canada ◽  
Migration Patterns ◽  
Migration Timing ◽  
Open Sea ◽  
And Migration

The migration patterns of marine fishes are poorly known, in part owing to the technical limitations associated with tracking the movements of animals in deep water. Here we document a large-scale, directed, migration of Atlantic cod (Gadus morhua) off eastern Canada. Our approach was based on the acoustic tagging of 126 fish and the deployment of 69 subsurface receivers, stretching over a 160-km distance along the edge of the Laurentian Channel. After 1 year of automated recording, we found that 65% of the fish migrated out of coastal waters in two distinct runs during the summer–autumn period. The offshore-migrating fish overwintered in deep Laurentian Channel waters, returning inshore in April. Individual migration routes and migration timing were variable, indicating that the cod did not aggregate in large schools during the seasonal migration events.

Sign in / Sign up

Export Citation Format

Share Document