Spatially based methods to assess the ecological status of riverine fish assemblages in European ecoregions

The aim of the present study was to determine whether boat-based deployment of remote underwater video cameras is effective for surveying fish assemblages in the deepest reaches of two large tropical rivers in north-eastern Australia. In addition, we compared fish assemblages recorded on baited versus unbaited cameras, and evaluated the sampling effort (duration of recording) required to estimate fish assemblages using remote underwater videos. We found that fish assemblages differed according to the depth, with statistically significant differences largely attributable to the prevalence of small-bodied species (Ambassis sp., Melanotaenia sp. and Pseudomugil signifer recorded in shallow (0.4–2.0m) and intermediate (2.1–4.9m) depths, and larger-bodied fish species (>10cm TL), such as Lutjanus argentimaculatus, Mesopristes argenteus and Caranx sexfasciatus, in deep water (>5.0m). Estimates of fish assemblage attributes generally stabilised after 60min recording duration, suggesting that interrogation of video footage beyond this duration may not be cost-effective. We conclude that depth is an important consideration when surveying large and deep river fish assemblages and that where water clarity is favourable, underwater video provides one of the means by which an assemblage can be investigated across the entire depth profile.

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Thirty years of environmental change reduces local, but not regional, diversity of riverine fish assemblages in a Himalayan biodiversity hotspot

Biological Conservation ◽

10.1016/j.biocon.2021.109427 ◽

2022 ◽

Vol 265 ◽

pp. 109427

Author(s):

David P. Gillette ◽

David R. Edds ◽

Bibhuti R. Jha ◽

Bhogendra Mishra

Keyword(s):

Environmental Change ◽

Fish Assemblages ◽

Biodiversity Hotspot ◽

Regional Diversity ◽

Riverine Fish

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Factors influencing riverine fish assemblages in Massachusetts

Scientific Investigations Report ◽

10.3133/sir20115193 ◽

2011 ◽

Cited By ~ 15

Author(s):

David S. Armstrong ◽

Todd A. Richards ◽

Sara B. Levin

Keyword(s):

Fish Assemblages ◽

Factors Influencing ◽

Riverine Fish

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Predicting New Zealand riverine fish reference assemblages

10.7287/peerj.preprints.26479v1 ◽

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.

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Environmental correlates of food-chain length, mean trophic level and trophic level variance in invaded riverine fish assemblages

The Science of The Total Environment ◽

10.1016/j.scitotenv.2018.06.304 ◽

2018 ◽

Vol 644 ◽

pp. 420-429 ◽

Cited By ~ 7

Author(s):

Alberto Maceda-Veiga ◽

Ralph Mac Nally ◽

Adolfo de Sostoa

Keyword(s):

Chain Length ◽

Trophic Level ◽

Food Chain ◽

Fish Assemblages ◽

Environmental Correlates ◽

Food Chain Length ◽

Mean Trophic Level ◽

Riverine Fish

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Temporal changes in fish abundance in response to hydrological variability in a dryland floodplain river

Marine and Freshwater Research ◽

10.1071/mf08118 ◽

2009 ◽

Vol 60 (2) ◽

pp. 146 ◽

Cited By ~ 73

Author(s):

Stephen R. Balcombe ◽

Angela H. Arthington

Keyword(s):

Fish Assemblages ◽

Arid Zone ◽

Fish Fauna ◽

Abundant Species ◽

Channel Flows ◽

Hydrological Variability ◽

Dryland River ◽

Floodplain Habitats ◽

Riverine Fish ◽

Harsh Conditions

Riverine fish living in unpredictable flow environments tend to be ecological generalists with traits that allow them to persist under highly variable and often harsh conditions associated with hydrological variation. Cooper Creek, an Australian dryland river, is characterised by extreme flow variability, especially in the magnitude, timing and duration of channel flows and floods, which, if they occur, do so mainly in summer. The present study examined the influence of hydrological variability on fish assemblages and abundance in four waterholes in the Windorah reach of Cooper Creek over eight occasions between 2001 and 2004. Antecedent flows had marked influences on fish species richness and assemblage structure. Following high summer flows, all waterholes supported a rich and abundant fish fauna, whereas fewer species and lower numbers were recorded following periods of zero channel flow. Recruitment of three of the four most common and abundant species was enhanced when intermittent flows inundated backwater and floodplain habitats that provide a food-rich environment. Opportunistic responses to rising channel flows and occasional large floods in Cooper Creek help to explain the prominent ‘boom’ patterns of fish production in this arid-zone river, whereas low-level recruitment during periods of low or no flow maintains populations of some species through the ‘bust’.

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