Distribution Of Freshwater Fishes Research Articles

Scale effects on the performance of niche-based models of freshwater fish distributions

Niche-based species distribution models (SDMs) have become an essential tool in conservation and restoration planning. Given the current threats to freshwater biodiversity, it is of fundamental importance to address scale effects on the performance of niche-based SDMs of freshwater species’ distributions. The scale effects are addressed here in the context of hierarchical catchment ordering, considered as counterpart to coarsening grain-size by increasing grid-cell size. We combine fish occurrence data from the Danube River Basin, the hierarchical catchment ordering and multiple environmental factors representing topographic, climatic and anthropogenic effects to model fish occurrence probability across multiple scales. We focus on 1st to 5th order catchments. The spatial scale (hierarchical catchment order) only marginally influences the mean performance of SDMs, however the uncertainty of the estimates increases with scale. Key predictors and their relative importance are scale and species dependent. Our findings have useful implications for choosing proper species dependent spatial scales for river rehabilitation measures, and for conservation planning in areas where fine grain species data are unavailable.

Diversity and distribution of fish fauna in the Ib River, a tributary of Mahanadi, India

Ichthyofaunal survey was conducted in the Ib River (21°44’ to 22°50’ N; 83°56’ to 83°54’ E), an important tributary of Mahanadi, to evaluate the diversity and distribution of freshwater fishes along six sites on seasonal basis between February, 2016 and January, 2017. A total of 55 species belonging to 42 genera, 21 families and 9 orders were recorded from the study area. Maximum number of species belonged to the Order Cypriniformes (41.8%) followed by Siluriformes (21.8%) and Perciformes (21.8%). Maximum value of species richness was observed in downstream areas; Sundargarh and Barghat and least in upper stretches of Pamsala. Shannon–Weiner diversity index ranged between 2.47 to 3.68 at the six sites of Ib River indicating healthy state of the river. Bray-Curtis similarity cluster analysis suggests that similarities between sites decrease with increasing distance, with highest similarity found between Sundargarh and Barghat sites. Baseline data on fish biodiversity has been generated in this study which can now be periodically monitored and form basis for future conservation plans.

A revision of the bioregionalisation of freshwater fish communities in the Australian Monsoonal Tropics.

The Australian freshwater fish fauna is very unique, but poorly understood. In the Australian Monsoonal Tropics (AMT) biome of northern Australia, the number of described and candidate species has nearly doubled since the last attempt to analyse freshwater fish species composition patterns and determine a bioregionalisation scheme. Here, we utilise the most complete database of catchment‐scale freshwater fish distributions from the AMT to date to: (a) reanalyze spatial patterns of species richness, endemism and turnover of freshwater fishes; (b) propose a biogeographic regionalisation based on species turnover; (c) assess the relationship between species turnover and patterns of environmental change and historic drainage connectivity; and (d) identify sampling gaps. Biogeographic provinces were identified using an agglomerative cluster analysis of a Simpson's beta (β sim) dissimilarity matrix. A generalised dissimilarity model incorporating eighteen environmental variables was used to investigate the environmental correlates of species turnover. Observed and estimated species richness and endemism were calculated and inventory completeness was estimated based on the ratio of observed to estimated species richness. Three major freshwater fish biogeographic provinces and 14 subprovinces are proposed. These differ substantially from the current bioregionalisation scheme. Species turnover was most strongly influenced by environmental variables that are interpreted to reflect changes in terrain (catchment relief and confinement), geology and climate (runoff perenniality, stream density), and biotic responses to climate (net primary productivity). Past connectivity between rivers during low sea‐level events is also influential highlighting the importance of historical processes in explaining contemporary patterns of biodiversity in the AMT. The inclusion of 49 newly discovered species and candidate species only reinforced known focal points of species richness and endemism in the AMT. However, a number of key sampling gaps remain that need to be filled to fully characterise the proposed bioregionalisation.

Into Africa via docked India: a fossil climbing perch from the Oligocene of Tibet helps solve the anabantid biogeographical puzzle

The northward drift of the Indian Plate and its collision with Eurasia have profoundly impacted the evolutionary history of the terrestrial organisms, especially the ones along the Indian Ocean rim. Climbing perches (Anabantidae) are primary freshwater fishes showing a disjunct south Asian-African distribution, but with an elusive paleobiogeographic history due to the lack of fossil evidence. Here, based on an updated time-calibrated anabantiform phylogeny integrating a number of relevant fossils, the divergence between Asian and African climbing perches is estimated to have occurred in the middle Eocene (ca. 40 Ma, Ma: million years ago), a time when India had already joined with Eurasia. The key fossil lineage is †Eoanabas, the oldest anabantid known so far, from the upper Oligocene of the Tibetan Plateau. Ancestral range reconstructions suggest a Southeast Asian origin in the early Eocene (ca. 48 Ma) and subsequent dispersals to Tibet and then India for this group. Thereby we propose their westbound dispersal to Africa via the biotic bridge between India and Africa. If so, climbing perch precursors had probably followed the paleobiogeographical route of snakehead fishes, which have a slightly older divergence between African and Asian taxa. As such, our study echoes some recent molecular analyses in rejecting the previously held “Gondwana continental drift vicariance” or late Mesozoic dispersal scenarios for the climbing perches, but provides a unique biogeographical model to highlight the role of the pre-uplift Tibet and the docked India in shaping the disjunct distribution of some air-breathing freshwater fishes around the Indian Ocean.

Provisional checklist of freshwater fish diversity and distribution in Perak, Malaysia, and some latest taxonomic concerns

This study investigates the published literature and incorporates our field data from 1997 to September 2018 to generate an inventory report of primary freshwater fishes for Perak State in Malaysia. We critically examined and enumerated 186 species from 2 classes, 16 orders, 43 families and 114 genera in 57 localities. A total of 173 fish species (91.4%) are native to Perak and 17 species (8.6%) are non-native. The provisional checklist presented herein is conservative and excludes doubtful inventory records that lack synthesis and traceability. We encountered seven taxonomic discrepancies and we also could not confidently identify eight species. These are explicitly discussed to inform future workers.

The Influence of Abiotic Environment and Connectivity on the Distribution of Diversity in an Andean Fish Fluvial Network

Abstract The distribution of Andean freshwater fishes is the result of the interaction of historical and contemporary factors such as basin geomorphology and the physicochemical characteristics of the water bodies. Dramatic changes along the river network due to waterfalls or dams generate dramatic changes in longitudinal slopes and fish assemblages because they function as ecological barriers to dispersal. We expect the amount of variation in beta diversity along the elevation gradient (between 700 and 3,500 m a.s.l.) of the eastern slope of the Cauca River basin to be explained by changes in the water environment and connectivity among sites. We measured connectivity in terms of the distance in the stream channel between sampling sites considering changes in slope. We used a Generalized Dissimilarity Model (GDM) to evaluate the contribution of connectivity and other water mass characteristics (dissolved oxygen, pH, conductivity, temperature, and elevation) in predicting changes in beta diversity. The GDM models explained 33% of the total variance in species turnover, suggesting that there are additional variables that have not been considered, such as available habitats along the rivers. Elevation was the variable with the largest relative importance in the model and connectivity only explained seven percent of the total variance when all sites were included. However, when only the sampling sites in the stream headers were included (most geographically isolated sites), the contribution due to connectivity increased to 51%. Isolation of stream headers, in conjunction with extreme conditions such as low water temperature, may influence the fish assemblage turnover. Our results provide evidence that elevation has a strong influence on beta diversity of Andean fish assemblages. Species turnover upstream above 1,200 m a.s.l. is strongly influenced by channel connectivity and there are additional environmental variables that need to be included in the models to improve their prediction power.

Environmental filtering governs the spatial distribution of alien fishes in a large, human‐impacted Mediterranean river

AbstractAimTo analyse the occurrence and abundance of native versus alien fish species in relation to climate, land use, hydrologic alteration and habitat fragmentation in a heavily invaded and human‐impacted riverine ecosystem. To test whether co‐occurrence patterns of native versus alien species are structured by environmental filtering or biotic associations.LocationMediterranean, Iberian Peninsula, Ebro River catchment.MethodsWe modelled freshwater fish distributions and their association with environmental conditions using a hurdle model‐like approach involving boosted regression trees. Additionally, we applied a joint species distribution model to quantify the co‐occurrence of native versus alien fish species that can be attributed to shared environmental responses or potentially to biotic interactions.ResultsOur results point to environmental factors, rather than biotic associations, as major correlates of the increase of alien and the decline of native fishes in the Ebro River. We observed contrasting patterns of native versus alien species along the upstream‐downstream gradient. Alien species dominated in the lower reaches associated with warmer temperatures, higher shares of intensive land use and appeared facilitated by dams and river regulation. Native species richness was highest in the larger tributaries followed by a strong decline in the main stem which was related to the river network position and land use type. Fragmentation played a subordinate role in explaining fish richness and abundance patterns.Main conclusionsGiven the strong association with temperature, a further range expansion of alien fishes in the Ebro with future climate change may be expected. More local‐scale factors related to habitat degradation and hydrologic alteration will further exacerbate the invasion success of many alien fishes. Further multiple, independent species introductions might mask isolation and fragmentation effects of dams on the future spread and distribution of alien fish.

Contrasting effects of dams with and without reservoirs on the population density of an amphidromous goby in southwestern Japan

Dam construction affects the distribution and abundance of freshwater fishes, particularly for diadromous species. Amphidromous fishes spawn in rivers, and hatched larvae descend to the sea (or standing water body such as lakes) immediately after hatching, grow there typically for a few months, and then ascend rivers as small juveniles. Landlocked populations of amphidromous fishes above dams and their migration between dam reservoirs and inlet streams (landlocked migration) have often been reported. In these cases, population density in the inlet streams may be increased by dam reservoirs, owing to reduced migration distance, which results in higher return rates. On the other hand, dams without reservoirs do not promote landlocked migration and merely act as a barrier to their upstream migration, resulting in decreased population density. In this study, we examined such contrasting effects of dams with and without reservoirs on the population density of an amphidromous goby, Rhinogobius fluviatilis, in two river systems (the Shigenobu and Yoshino Rivers) of Shikoku Island, Japan. In the Shigenobu River, where more than 300 sediment-control dams and weirs (barriers without reservoirs) have been installed, our analysis showed that the goby density decreased sharply with increasing the number of barriers higher than or equal to 2 m. On the other hand, in the Yoshino River, where we investigated both landlocked populations above water storage dams (with reservoirs) and non-landlocked populations in tributaries without water storage dams, the analysis showed that the goby density increased with decreasing the distance from standing water body (i.e. the sea or dam reservoirs). Furthermore, monthly surveys at sites above and below a water storage dam showed that the recruitment of ascending juveniles above the dam was more abundant and seasonally earlier than that below the dam, probably owing to reduced migration distance and increased return rates. Our results have implications for understanding how dams alter natural distribution patterns of amphidromous fishes.

Fish Species Diversity, Distribution, and Dispersal in the Rivers of the Penzhina Bay Catchment Area

New expedition data, analysis of unpublished archives, and questionnaire information made it possible to clarify the ichthyofauna species diversity and to assess the distribution of freshwater, anadromous, and semianadromous fishes in the largest and some small rivers of the Penzhina Bay basin. The results indicate that the lower reaches of the rivers are inhabited by 11 anadromous species and ten freshwater species, including five whitefish species. The most diverse freshwater fish complex is revealed off the northern coast of the Sea of Okhotsk. Freshwater fauna exchange under modern conditions is possible through the sources of the largest river systems during the most severe spring floods (both within the Penzhina Bay basin and in adjacent basins of the East Siberian and Bering seas). In the apex of Penzhina Bay, the modern sea-coast regional dispersal takes place only between the rivers with joint mouths. This path is provided by extremely strong tidal currents and considerable freshening of coastal areas during the floods.

Phylogeography of the widespread creek chub Semotilus atromaculatus (Cypriniformes: Leuciscidae).

The extent and nature of genetic differentiation in Semotilus atromaculatus, one of the most abundant and widespread leuciscids in North America, were evaluated based on mitochondrial (mt) and nuclear DNA sequence variation. Phylogenetic relationships were first inferred based on a fragment of the cytochrome b (cytb) region and the nuclear intron s7 gene for S. atromaculatus and all other congeners as well as representative species from all other genera in the creek chub-plagopterin clade. The phylogeography of major haplogroups of S. atromaculatus was also assessed according to variation in a fragment of the mitochondrial cytb region from 567 individuals across its range. All analyses identified S. thoreauianus, S. lumbee and S. corporalis as reciprocally monophyletic groups. Analyses of nuclear sequence variation resolved S. atromaculatus as a single clade, where S. thoreauianus and S. lumbee were recovered as the sister group to S. atromaculatus, and S. corporalis was resolved as sister to all other species in the genus. Analyses of mtDNA sequence variation recovered S. atromaculatus as three well supported and differentiated monophyletic groups, with a widespread genetically homogeneous lineage extending across most of the current range of the species; a more geographically restricted and geographically structured lineage in the southern Appalachians, sister group to S. lumbee; and a geographically restricted lineage was identified from two Gulf Slope basins. Evidence of complex mito-nuclear discordance and phylogeographic differentiation within S. atromaculatus illustrates that further analysis of widespread species is warranted to understand North American freshwater fish diversity and distributions.

Decline in New Zealand's freshwater fish fauna: effect of land use

The number of New Zealand’s freshwater fish listed as threatened has increased since 1992 when the first New Zealand threat classification system list was compiled. In this study, temporal and land cover-related trends were analysed for data on freshwater fish distribution, comprising more than 20000 records for the 47 years from January 1970 to January 2017 from the New Zealand Freshwater Fish Database. The analysis included individual species abundance and distribution trends, as well as an index of fish community integrity, namely the Index of Biotic Integrity (IBI). Of the 25 fish species that met the requirements for analysis to determine changes in the proportion of sites they occupied over time, 76% had negative trends (indicating declining occurrence). Of the 20 native species analysed for the proportion of sites occupied over time, 75% had negative trends; 65% of these were significant declines and more species were in decline at pasture sites than natural cover sites. The average IBI score also declined over the time period and, when analysed separately, the major land cover types revealed that the IBI declined at pasture catchment sites but not at sites with natural vegetation catchments.

Connections and containers: Using genetic data to understand how watershed evolution and human activities influence cutthroat trout biogeography.

Species with large geographic distributions often exhibit complex patterns of diversity that can be further complicated by human activities. Cutthroat trout (Oncorhynchus clarkii) are one of the most widely distributed freshwater fish species in western North America exhibiting substantial phenotypic and genetic variability; however, fish stocking practices have translocated populations outside of their native range and may have obscured intraspecific boundaries. This study focuses on cutthroat trout populations representing three distinct evolutionary clades that are found intermixed within a contact zone between the Bonneville and upper Snake River watersheds in the western United States. We used mitochondrial and microsatellite genetic data, as well as historical stocking records, to evaluate whether populations of cutthroat trout in the contact zone are native or are introduced. We found significant genetic differentiation and fine-scale genetic population structure that was organized primarily by watershed boundaries. While we detected increased genetic diversity in some areas in close proximity to the greatest number of stocking events, the highly organized population structure both within and between areas of the contact zone indicates that the populations are native to the watersheds. Intermixing of distinct evolutionary lineages of cutthroat trout appears to be the result of historical connections between paleodrainages. Our analyses provide a context for understanding how genetic data can be used to assess the status of populations as native or introduced.

Predicting New Zealand riverine fish reference assemblages

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.

한반도 담수어류의 분포와 다양성

한반도 담수어류의 분포와 다양성

Real-time distribution of pelagic fish: combining hydroacoustics, GIS and spatial modelling at a fine spatial scale

Understanding spatial distribution of organisms in heterogeneous environment remains one of the chief issues in ecology. Spatial organization of freshwater fish was investigated predominantly on large-scale, neglecting important local conditions and ecological processes. However, small-scale processes are of an essential importance for individual habitat preferences and hence structuring trophic cascades and species coexistence. In this work, we analysed the real-time spatial distribution of pelagic freshwater fish in the Římov Reservoir (Czechia) observed by hydroacoustics in relation to important environmental predictors during 48 hours at 3-h interval. Effect of diurnal cycle was revealed of highest significance in all spatial models with inverse trends between fish distribution and predictors in day and night in general. Our findings highlighted daytime pelagic fish distribution as highly aggregated, with general fish preferences for central, deep and highly illuminated areas, whereas nighttime distribution was more disperse and fish preferred nearshore steep sloped areas with higher depth. This turnover suggests prominent movements of significant part of fish assemblage between pelagic and nearshore areas on a diel basis. In conclusion, hydroacoustics, GIS and spatial modelling proved as valuable tool for predicting local fish distribution and elucidate its drivers, which has far reaching implications for understanding freshwater ecosystem functioning.

Molecular and morphological data of the freshwater fish Glandulocauda melanopleura (Characiformes: Characidae) provide evidences of river captures and local differentiation in the Brazilian Atlantic Forest.

The current distribution of freshwater fishes across multiple basins along Eastern Brazil can be associated to two main events: river captures or temporary paleoconnections. Apparently, river captures had a more significant role on distribution and structuring of species from upland areas, such as Glandulocauda melanopleura. Populations of this species are found in contiguous drainages in presently isolated upper parts of Rio Tietê and the coastal basins of Guaratuba, Itatinga, Itanháem, and Ribeira de Iguape, in the Atlantic Forest domain. The allopatric and disjoint distribution of G. melanopleura associated with variation of morphological characters detected among geographically isolated populations stimulated this study. Thus, an integrative approach was undertaken, including morphological and molecular data, to better understand the evolutionary history of the species and the area where it occurs. Molecular analyses based on two mitochondrial markers revealed a strong genetic structure within G. melanopleura, that allowed recognition of two lineages, one distributed in both the upper Tietê and Itanhaém and the other in the Guaratuba. Overall, morphological data revealed some intraspecific overlapping variation, indicating that all samples are conspecific. Phylogenetic and phylogeographic analyses allied to divergence times and geomorphological information indicate that the current distribution of G. melanopleura is a result of relatively recent river captures involving the Tietê and some other coastal drainages. Although of recent origin, they occurred long enough to completely isolate these populations, since there are no haplotypes sharing between them. The conservation status of this species is also discussed, and our results corroborate the need to understand population structure for conservation planning.

Fresh Water Fish Distribution and Diversity of the Cauvery River at Mukkombo Region in Tamil Nadu

Fresh water is critical to human society and sustains all terrestrial ecosystems. Even though India has a large spread of fresh water resources, most systems are threatened due to anthropogenic activities leading to serious threats to fish diversity. Hence conservation and management are critical to the interests of all humans, nations and governments and hence the present study. Results show that the system recorded 33 species belonging to six orders, 14 families and 19 genera. In terms of percentage, Cypriniformes formed 36.36%, followed by Siluriformes recording 33.33% and Perciformes (21.21%); while Osteoglossiformes, Mugiliformes and Anguilliformes each formed3.03% of the total fish species.

Diversity and longitudinal distribution of freshwater fish in Klawing River, Central Java, Indonesia

Suryaningsih S, Sukmaningrum S, Simanjuntak SBI, Kusbiyanto. 2018. Diversity and longitudinal distribution of freshwater fish in Klawing River, Central Java, Indonesia. Biodiversitas 19: 85-92. The aims of this study were to evaluate the diversity and longitudinal distribution of fish in Klawing River, Purbalingga (Central Java). The survey was performed using a clustered random-sampling technique. The river was divided into upstream, midstream and downstream regions. Species diversity was measured as the number of species, and the longitudinal distribution was assessed by determining the fish species present in each of the three regions. Eighteen fish species of eleven families were identified in the Klawing River: Cyprinidae, Bagridae, Mastacembelidae, Anabantidae, Cichlidae, Channidae, Eleotrididae, Beleontinidae, Osphronemidae, Poecilidae, and Siluridae. Cyprinidae exhibited the highest number of species (six), followed by Bagridae and Cichlidae (two species each). The other families were represented by one species each. A single cluster analysis showed that the upstream population had a similarity of 78% and 50% with the midstream and downstream populations, respectively. Species and family diversities were higher in the midstream populations than in the upstream and downstream populations. This longitudinal distribution may be due to differences in environmental conditions and suggests that management of the land surrounding the Klawing River is a key factor in the conservation of freshwater fish.

Species introduction and taxonomic homogenization of Spanish freshwater fish fauna in relation to basin size, species richness and dam construction

The introduction of exotic species is a key global threat to biodiversity. Beyond an increased risk of native species extinction, there exists a loss of biodiversity distinctiveness. Nevertheless, quantitative information on biotic homogenization at the taxonomic level in relation to basin features is rare. We used freshwater fish distribution data in Spain at three different time periods (1952, 1995, and 2007) to assess the species introduction process and the temporal dynamics of taxonomic homogenization among river basins in relation to basin size, native species richness and dam construction variables. The degree of alteration of original faunas by species introduction has increased through time, especially in native richer species, which suggest that the number of non-native and native species covariate with environmental heterogeneity. On the other hand, neither basin size nor habitat modification by dam construction seems to explain the number of introduced species. Our results indicate that the taxonomic homogenization of Spanish fish fauna is a temporally and spatially dynamic process; initial local increases in β-diversity through species introduction could be blurred because of scaling to regional and national levels or by the continuous expansion of a reduced number of exotic species.

Vulnerability of Cape Fold Ecoregion freshwater fishes to climate change and other human impacts

Abstract Native freshwater fish populations throughout South Africa's Cape Fold Ecoregion (CFE) are in decline as a result of human impacts on aquatic habitats, including the introduction of non‐native freshwater fishes. Climate change may be further accelerating declines of many species, although this has not yet been studied in the CFE. This situation presents a major conservation challenge that requires assigning management priorities through assessing species in terms of their vulnerability to climate change. One factor hindering reliable vulnerability assessments and the concurrent development of effective conservation strategies is limited knowledge of the biology and population status of many species. This paper reports on a study employing a rapid assessment method used in the USA, designed to capitalize on available expert knowledge to supplement existing empirical data, to determine the relative vulnerabilities of different species to climate change and other human impacts. Eight local freshwater fish experts conducted vulnerability assessments on 20 native and 17 non‐native freshwater fish species present in the CFE. Results show (1) that native species were generally classified as being more vulnerable to extinction than were non‐native species, (2) that the climate change impacts are expected to increase the vulnerability of most native, and some non‐native, species, (3) that vulnerability hotspots requiring urgent conservation attention occur in the Olifants‐Doring, upper Berg and upper Breede River catchments in the south west of the region, (4) that in addition to providing guidance for prioritizing management interventions, this study highlights the need for reliable data on the biology and distribution of many CFE freshwater fishes, and (5) that identification of priority areas for protection should be based on multiple sources of data.