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 Analysing Habitat Connectivity and Home Ranges of Bigmouth Buffalo and Channel Catfish Using a Large-Scale Acoustic Receiver Network

2019 ◽  
Vol 11 (11) ◽  
pp. 3051 ◽  
Author(s):  
Eva C. Enders ◽  
Colin Charles ◽  
Douglas A. Watkinson ◽  
Colin Kovachik ◽  
Douglas R. Leroux ◽  
...  
Keyword(s):  
Ictalurus Punctatus ◽  
Channel Catfish ◽  
Large Scale ◽  
River System ◽  
The United States ◽  
Fish Passage ◽  
Biological Knowledge ◽  
Home Ranges ◽  
Fish Movement ◽  
Lake Winnipeg

The determination if fish movement of potadromous species is impeded in a river system is often difficult, particularly when timing and extent of movements are unknown. Furthermore, evaluating river connectivity poses additional challenges. Here, we used large-scale, long-term fish movement to study and identify anthropogenic barriers to movements in the Lake Winnipeg basin including the Red, Winnipeg, and Assiniboine rivers. In the frame of the project, 80 Bigmouth Buffalo (Ictiobus cyprinellus) and 161 Channel Catfish (Ictalurus punctatus) were tagged with acoustic transmitters. Individual fish were detected with an acoustic telemetry network. Movements were subsequently analyzed using a continuous-time Markov model (CTMM). The study demonstrated large home ranges in the Lake Winnipeg basin and evidence of frequent transborder movements between Canada and the United States. The study also highlighted successful downstream fish passage at some barriers, whereas some barriers limited or completely blocked upstream movement. This biological knowledge on fish movements in the Lake Winnipeg basin highlights the need for fish passage solutions at different obstructions.

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.

Prioritising the rehabilitation of fish passage in a regulated river system based on fish movement

2015 ◽  
Vol 16 (1) ◽  
pp. 67-72 ◽  
Author(s):  
Justin O'Connor ◽  
Frank Amtstaetter ◽  
Matthew Jones ◽  
John Mahoney
Keyword(s):  
River System ◽  
Fish Passage ◽  
Regulated River ◽  
Fish Movement

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.

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.

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.

Out in the wash: spatial ecology of a temperate marine shallow rocky-reef species derived using acoustic telemetry

2015 ◽  
Vol 66 (6) ◽  
pp. 559 ◽  
Author(s):  
Jerom R. Stocks ◽  
Charles A. Gray ◽  
Matthew D. Taylor
Keyword(s):  
Spatial Ecology ◽  
Large Scale ◽  
Spatial Information ◽  
Activity Space ◽  
Rocky Reef ◽  
Temperate Reef ◽  
Detection Frequency ◽  
Detection Depth ◽  
Eastern Australia ◽  
Temperate Reef Fish

Characterising the movement and habitat affinities of fish is a fundamental component in understanding the functioning of marine ecosystems. A comprehensive array of acoustic receivers was deployed at two near-shore coastal sites in south-eastern Australia, to examine the movements, activity-space size and residency of a temperate rocky-reef, herbivorous species Girella elevata. Twenty-four G. elevata individuals were internally tagged with pressure-sensing acoustic transmitters across these two arrays and monitored for up to 550 days. An existing network of coastal receivers was used to examine large-scale movement patterns. Individuals exhibited varying residency, but all had small activity-space sizes within the arrays. The species utilised shallow rocky-reef habitat, displaying unimodal or bimodal patterns in depth use. A positive correlation was observed between wind speed and the detection depth of fish, with fish being likely to move to deeper water to escape periods of adverse conditions. Detection frequency data, corrected using sentinel tags, generally illustrated diurnal behaviour. Patterns of habitat usage, residency and spatial utilisation highlighted the susceptibility of G. elevata to recreational fishing pressure. The results from the present study will further contribute to the spatial information required in the zoning of effective marine protected areas, and our understanding of temperate reef fish ecology.

Fungi and fire in Australian ecosystems: a review of current knowledge, management implications and future directions

2011 ◽  
Vol 59 (1) ◽  
pp. 70 ◽  
Author(s):  
Sapphire J. M. McMullan-Fisher ◽  
Tom W. May ◽  
Richard M. Robinson ◽  
Tina L. Bell ◽  
Teresa Lebel ◽  
...  
Keyword(s):  
Fungal Community ◽  
Large Scale ◽  
Current Knowledge ◽  
Vegetation Type ◽  
Fire Regimes ◽  
Trophic Group ◽  
Fire Intensity ◽  
Specific Information ◽  
Eastern Australia ◽  
Essential Components

Fungi are essential components of all ecosystems in roles including symbiotic partners, decomposers and nutrient cyclers and as a source of food for vertebrates and invertebrates. Fire changes the environment in which fungi live by affecting soil structure, nutrient availability, organic and inorganic substrates and other biotic components with which fungi interact, particularly mycophagous animals. We review the literature on fire and fungi in Australia, collating studies that include sites with different time since fire or different fire regimes. The studies used a variety of methods for survey and identification of fungi and focussed on different groups of fungi, with an emphasis on fruit-bodies of epigeal macrofungi and a lack of studies on microfungi in soil or plant tissues. There was a lack of replication of fire treatment effects in some studies. Nevertheless, most studies reported some consequence of fire on the fungal community. Studies on fire and fungi were concentrated in eucalypt forest in south-west and south-eastern Australia, and were lacking for ecosystems such as grasslands and tropical savannahs. The effects of fire on fungi are highly variable and depend on factors such as soil and vegetation type and variation in fire intensity and history, including the length of time between fires. There is a post-fire flush of fruit-bodies of pyrophilous macrofungi, but there are also fungi that prefer long unburnt vegetation. The few studies that tested the effect of fire regimes in relation to the intervals between burns did not yield consistent results. The functional roles of fungi in ecosystems and the interactions of fire with these functions are explained and discussed. Responses of fungi to fire are reviewed for each fungal trophic group, and also in relation to interactions between fungi and vertebrates and invertebrates. Recommendations are made to include monitoring of fungi in large-scale fire management research programs and to integrate the use of morphological and molecular methods of identification. Preliminary results suggest that fire mosaics promote heterogeneity in the fungal community. Management of substrates could assist in preserving fungal diversity in the absence of specific information on fungi.

Sign in / Sign up

Export Citation Format

Share Document