Distribution Of Freshwater Fishes Research Articles

Biogeographical indices of the freshwater fish spatial distribution in the upper reaches of the Yangtze River

The spatial distribution of freshwater fish species (Total species and Unique species) in the upper reaches of the Yangtze River was studied, focusing on the spatial distribution of geographic ranges. Two biogeographical indices: environmental resistance (R50), anisotropy (A50) and a fractal dimension method were used to identify the relationship between them and spatial distribution of freshwater fish. R50 quantifies the loss of biotic resemblance occurring from any point in the map to the rest of the study area. A50 quantifies the extent to which the perimeter: area ratio of the geographical ranges of all species whose distributions overlap at any particular location depart from the perimeter of area ratio of a circle. We concluded that the western of the study area is populated by a large number of total and unique species, the eastern part with the total species richness, the middle regions populated by small number of unique species, the mid-west region populated by small number of total species, and the mid-eastern region populated by a large number of total species. We also analyzed how topology affects the spatial arrangement of species, species density has strong curvilinear correlation (species density increases with increased of fractal dimension), the species density in the tributaries is lower than that in mainstream. The results and methods used give us detailed information about the spatial distribution of species, so as to illuminate the species distribution and change by the human activities.

Thesis abstract: Potential impacts of climate change on the distribution of freshwater fishes in French streams and uncertainty of projections

news and update ISSN 1948-6596 thesis abstract Potential impacts of climate change on the distribution of fresh- water fishes in French streams and uncertainty of projections Laetitia Buisson PhD, Laboratoire Evolution et Diversite Biologique, Universite Paul Sabatier, Toulouse, and La- boratoire d’Ecologie Fonctionnelle, ENSAT, Castanet-Tolosan, France Current address: Laboratoire Evolution et Diversite Biologique, Universite Paul Sabatier, Tou- louse, France; E-mail: buisson@cict.fr; http://www.edb.ups-tlse.fr/ Climate change and its impact on biodiversity are receiving increasing attention from scientists and people managing natural ecosystems. Recent modifications of climate have induced diverse functional (e.g. phenology, physiology) and struc- tural (e.g. species distribution shifts, range con- traction, local extinctions) responses among or- ganisms (Walther et al. 2002). Given the projec- tions of future climate change, these responses are expected to continue throughout the 21st century and climate change could thus have major consequences on species and assemblages. A common approach to project the potential im- pacts of environmental changes on the distribu- tion of biodiversity is the use of species distribu- tion models (SDM) (e.g. Thuiller 2003). These cor- relative models first relate the present-day spe- cies distribution to a set of climate and other envi- ronmental descriptors. Then, the application of scenarios of future climate changes provides pre- dictions of the habitats potentially suitable in the future for the species. In spite of their widespread use, a growing concern has emerged for the vari- ability in the predicted impacts by such models due to the methodological decisions taken during the modeling process (Thuiller 2004). Improve- ments in the accuracy of predictions combined with an estimation of the uncertainty inherent to those predictions are thus urgently needed. Among freshwater ecosystems, stream fish have no physiological ability to regulate their body temperature and could therefore be very sensitive to climate warming, especially cold-stenotherm fish such as salmonid species. Stream fish also have to cope with hydrological variability of streams and strong anthropogenic pressures (e.g. habitat loss, stream fragmentation). In addition, they have limited dispersal ability within hydro- graphic networks in which they currently live. Yet their response to current and future climate change has been poorly documented and few studies have used SDM to assess the potential consequences of the on-going climate change on freshwater fish species distribution, especially in European streams. In that context, the aim of my PhD thesis was to assess the potential impacts of climate change on fish in French streams, mainly on spe- cies distribution and assemblages’ structure. I used fish data provided by the Office National de l’Eau et des Milieux Aquatiques (ONEMA), the in- stitution in charge of the protection and conserva- tion of freshwater ecosystems in France. These data were combined with climate and environ- mental descriptors through the use of correlative statistical modeling. As my goal was to provide reliable estimates of the future impacts of climate change on stream fish, I have considered recent criticisms (e.g. choice of statistical method, pure bioclimatic models) of species distribution models by justifying each step and optimizing the use of such models. In all, five papers are derived from my PhD work. The first three papers set the bases for the building of the models by considering the uncertainty in predictions, while the latest two assess the impacts of climate change on stream fish species and assemblages. In stream fish ecology, many studies have been conducted to identify the environmental drivers structuring fish assemblages (reviewed in Matthews 1998). It appears that fish species distri- bution and structure of fish assemblages are de- termined by a complex interplay of biotic, abiotic and spatial factors (Jackson et al. 2001). Disentan- © 2009 the authors; journal compilation © 2009 The International Biogeography Society — frontiers of biogeography 1.2, 2009

Interbasin Water Transfer, Riverine Connectivity, and Spatial Controls on Fish Biodiversity

BackgroundLarge-scale inter-basin water transfer (IBWT) projects are commonly proposed as solutions to water distribution and supply problems. These problems are likely to intensify under future population growth and climate change scenarios. Scarce data on the distribution of freshwater fishes frequently limits the ability to assess the potential implications of an IBWT project on freshwater fish communities. Because connectivity in habitat networks is expected to be critical to species' biogeography, consideration of changes in the relative isolation of riverine networks may provide a strategy for controlling impacts of IBWTs on freshwater fish communities.Methods/Principal FindingsUsing empirical data on the current patterns of freshwater fish biodiversity for rivers of peninsular India, we show here how the spatial changes alone under an archetypal IBWT project will (1) reduce freshwater fish biodiversity system-wide, (2) alter patterns of local species richness, (3) expand distributions of widespread species throughout peninsular rivers, and (4) decrease community richness by increasing inter-basin similarity (a mechanism for the observed decrease in biodiversity). Given the complexity of the IBWT, many paths to partial or full completion of the project are possible. We evaluate two strategies for step-wise implementation of the 11 canals, based on economic or ecological considerations. We find that for each step in the project, the impacts on freshwater fish communities are sensitive to which canal is added to the network.Conclusions/SignificanceImportantly, ecological impacts can be reduced by associating the sequence in which canals are added to characteristics of the links, except for the case when all 11 canals are implemented simultaneously (at which point the sequence of canal addition is inconsequential). By identifying the fundamental relationship between the geometry of riverine networks and freshwater fish biodiversity, our results will aid in assessing impacts of IBWT projects and balancing ecosystem and societal demands for freshwater, even in cases where biodiversity data are limited.

Variation in fish community structure, richness, and diversity in 56 Danish lakes with contrasting depth, size, and trophic state: does the method matter?

The distribution of freshwater fish is influenced by food availability, habitat heterogeneity, competition, predation, trophic state, and presence/absence of macrophytes. This poses a challenge to monitoring, and researchers have been struggling to develop accurate sampling methods for obtaining a better understanding of fish communities. We compare fish community composition, richness, and diversity in 56 Danish lakes using data obtained by gillnetting in different lake zones and near-shore electrofishing, respectively. On average, electrofishing captured more species than offshore gillnets, but not more than littoral gillnets. Overall, the different fish sampling methods showed consistency as to fish community structure, but noticeable differences in community–environment relationships. Lake area was the best predictor for fish species richness in the littoral samplings, while it was poor for offshore samplings. Electrofishing was more efficient than gillnets at catching pike (Esox lucius), eel (Anguilla anguilla), and tench (Tinca tinca), whereas pelagic gillnets were better for catching pikeperch (Sander lucioperca) and perch (Perca fluviatilis). Independently of methods, the total number per unit of effort and weight per unit of effort were generally positively related to summer chlorophyll a, and, for offshore nets, negatively related to average depth. Our results show that sampling restricted to specific habitats within the lakes does not provide a representative of the whole-lake fish community, as all methods miss some important species that other methods capture. However, electrofishing seems to be a fast alternative to gillnets for monitoring fish species richness and composition in littoral habitats of Danish lakes.

Population genetic structure in the Iberian cyprinid fish Iberochondrostoma lemmingii (Steindachner, 1866): disentangling species fragmentation and colonization processes

Interplay between the complex geography, hydrogeomorphological history, past climatic changes, and anthropogenic pressures is likely responsible for the current diversity and species' distribution of freshwater fishes in the Iberian Peninsula. To further disentangle the evolutionary processes promoting the diversification of endemic Iberian Cyprinids through time and space, we explored the patterns of genetic diversity of the Iberian arched‐mouth nase, Iberochondrostoma lemmingii (Steindachner, 1866), using molecular markers rendering at different timescales: the mitochondrial gene cytochrome b and seven microsatellite loci. Both markers showed significant differentiation of populations though the relative genetic distances among populations were different between markers. Mitochondrial DNA results indicate the isolation of hydrographic basins as the main driver of population differentiation, with Tejo as the centre of diversification. The results also support connections between Tejo, Guadiana, and Guadalquivir, with levels of divergence suggesting an earlier severance of Guadalquivir, whereas Guadiana and Tejo maintained connections until a more recent past. Establishment of more peripherial populations in small southern basins (Quarteira and Almargem) could have been ruled by founder events. However, the analysis of present‐day genetic configuration suggested by microsatellite data implies, for the first time, the involvement of other factors in the evolution of arched‐mouth Iberian nase populations. Relative low genetic distances between inter‐basin populations (Tejo and Guadiana) and the lack of concordance between differentiation and geography suggest a possible influence of human‐mediated translocations in the population genetic patterns of I. lemmingii. High intra‐basin differentiation levels were found within Tejo and Guadiana and may be associated with factors intrinsic to the species (e.g. low dispersal capability) or natural and/or artificial barriers to gene flow. The low vagility of the species appears to be an important factor influencing the evolutionary processes shaping the phylogeographical patterns of I. lemmingii, which could be relevant for the conservation of this threatened species. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105, 559–572.

Genetic structure and diversity of introduced eastern mosquitofish (Gambusia holbrooki) in south-eastern Australia

The closely related eastern mosquitofish (Gambusia holbrooki) and western mosquitofish (Gambusia affinis) have been introduced into many countries and collectively represent the most widely distributed freshwater fish in the world. We investigated genetic patterns associated with the spread of G. holbrooki in its introduced range in south-eastern Australia, by sampling 60 G. holbrooki populations (n = 1771) from major regions where G. holbrooki was initially introduced into Australia, and characterising the genetic diversity and population structure of G. holbrooki, using five polymorphic nuclear microsatellite loci and sequences from two mitochondrial genetic markers. Results were compared with published data on American and European Gambusia samples and historical records. Low microsatellite diversity and strong population genetic structuring were found within G. holbrooki in south-eastern Australia. Observed heterozygosity and allelic richness declined regionally in the order Sydney, Brisbane, Canberra, Melbourne and Adelaide. Microsatellite variation in Australia was reduced compared with native populations. Two mitochondrial DNA haplotypes of G. holbrooki were found; one was common, whereas the other was detected in one Sydney population and one Melbourne population. Cytochrome b sequence diversity was reduced compared with native and European ranges, and sequences were identical to two haplotypes previously identified. Microsatellite diversity of G. holbrooki in south-eastern Australia validates historical records of its spread, beginning north and moving south. Mitochondrial sequencing confirms that G. holbrooki is present in Australia, but the origins of Australian G. holbrooki populations remain unclear.

A delineation of Nuclear Middle America biogeographical provinces based on river basin faunistic similarities

The biogeographical patterns of the obligate freshwater fishes of Nuclear Middle America, a region that expands from southern Guatemala to northern Nicaragua, are described herein. Historically, three broad ichthyological provinces have been assigned to Nuclear Middle America: the Usumacinta, and the San Juan in the Atlantic slope and the Chiapas-Nicaraguense in the Pacific slope. With the use of correspondence analysis and unweighted pair group method with arithmetic mean cluster analysis of a presence/absence matrix of 76 obligate freshwater fishes, we identified four ichthyological provinces in Nuclear Middle America: (1) the Honduras and Guatemala Caribbean Highlands Province, (2) the Honduras and Nicaragua Mosquitia Province, (3) the Chiapas-El Salvador-Nacaome Province, and (4) the Choluteca and Nicaragua Pacific Province. Differences between provinces in species composition and species turnover between provinces were tested by analysis of similarity, the calculation of beta-diversity indices and an indicator species analysis. We then further characterized each province by identifying the number of endemics and classifying species according to their salinity tolerance. The most striking patterns of Nuclear Middle America freshwater fish distribution are its paucity of primary freshwater fishes and limited numbers of endemics. The four ichthyological provinces are distinct as indicated by the ANOSIM and beta-diversity analysis, although one province showed low beta-diversity values. These results suggest that, despite of the active geological history that characterized the region, there has been limited isolation of species in any given province, and historical drainage connectivity has been high.

Does longitudinal connectivity loss affect the distribution of freshwater fish?

Loss of natural river network connectivity is presumed to be one of the more generalized and important human-induced alterations in natural environments and is frequently perceived as one of the main causes of the decline of freshwater fish species.The purpose of the present study was to ascertain the impact of barriers on the distribution of freshwater fish species with distinct life histories. In this study 196 sites in three river basins in Western Iberia were sampled and analyzed for the presence of barriers. Three alternative analytical approaches based on Generalized Linear Models (GLM) were used to test the contribution of connectivity-related variables to species distribution: (1) explore whether connectivity-related variables are included in the best-fitting distribution models; (2) use models calibrated at non-disturbed sites to compute deviations from model predictions made at sites with connectivity-related disturbances; and (3) use a hierarchical partitioning approach, in which the improvement of model fit due to the inclusion of connectivity as a predictor variable is assessed using all possible variable combinations.The results indicate a general lack of influence of barriers on freshwater fish species distributions. The effects of environment and human pressures exceeded the isolated effect of connectivity losses. Further studies based on experimental designs that are more specifically directed at this specific issue are needed in order to fully understand the effects of barriers on species and communities. A more thorough assessment of the effects of connectivity on fish is crucial to the implementation of adequate restoration actions that are in turn needed to achieve the goals of the European Water Framework Directive.

Freshwater fish biodiversity in the River Ganga (India): changing pattern, threats and conservation perspectives

The river Ganges is the largest river in India and the fifth longest in the world. Although, many studies on fish ecology and systematic have been conducted largely to improve fisheries but fish diversity and their distribution pattern from conservation point of view have never been adequately addressed in the Ganges. In this connection, current distribution and abundance of freshwater fishes of river Ganges was studied and assessed from April 2007 to March 2009. We documented and described 143 freshwater fish species in the all stretches of the river which is higher than what was reported earlier. Some species were observed with shift in their distribution ranges. First time, a total of 10 exotic fishes, including Pterygoplichthys anisitsi, which has never been reported from India found in the Ganges. Alterations of the hydrological pattern due to various types of hydro projects was seems to be the largest threat to fishes of Ganges. Indiscriminate and illegal fishing, pollution, water abstraction, siltation and invasion of exotic species are also threatening the fish diversity in the Ganges and as many as 29 species are listed under threatened category. The study advocates a need to identify critical fish habitats in the Ganga basin to declare them as conservation reserves to mitigate the loss of fish diversity from this mighty large river.

Conservation status and distribution of freshwater fishes in South African national parks

Thirteen of South Africa’s national parks contain aquatic systems which support 63 indigenous and 11 alien freshwater fishes. Indigenous fishes include 43 species of the Zambezian faunal group (70% of the national total), eight Karroid (47%), five Cape (31%) and seven species of Marine origin (79%). Six represented Zambezian species, two Marine origin, and all of the Cape and Karroid species are endemic to South Africa. Only three threatened species naturally occur within national parks (Serranochromis meridianus, Barbus andrewi, Pseudobarbus afer ) all of which are classified as Endangered. Two extralimital IUCN threatened species (Chetia brevis and Oreochromis macrochir ) have been introduced. At least three of the five lineages of Galaxias zebratus and two of the four lineages of Pseudobarbus afer occur within national parks in the Cape region. Many fish populations within national parks remain threatened, particularly by hydraulic alterations, impoundment, and predation by alien fishes. There are few aquatic systems within national parks where one or more of these threats are not prominent, and these collectively support only half of the freshwater fish species occurring in all national parks. Proposed management actions include determination and implementation of Environmental Flow Reserves in stressed systems, management of existing alien fish populations and prevention of new establishments, and regular assessments of fish communities.

Conservation Status and Distribution of Freshwater Fishes in South African National Parks

Thirteen of South Africa's national parks contain aquatic systems which support 63 indigenous and 11 alien freshwater fishes. Indigenous fishes include 43 species of the Zambezian faunal group (70% of the national total), eight Karroid (47%), five Cape (31%) and seven species of Marine origin (79%). Six represented Zambezian species, two Marine origin, and all of the Cape and Karroid species are endemic to South Africa. Only three threatened species naturally occur within national parks (Serranochromis meridianus, Barbus andrewi, Pseudobarbus afer) all of which are classified as Endangered. Two extralimital IUCN threatened species (Chetia brevis and Oreochromis macrochir) have been introduced. At least three of the five lineages of Galaxias zebratus and two of the four lineages of Pseudobarbus afer occur within national parks in the Cape region. Many fish populations within national parks remain threatened, particularly by hydraulic alterations, impoundment, and predation by alien fishes. There are few aquatic systems within national parks where one or more of these threats are not prominent, and these collectively support only half of the freshwater fish species occurring in all national parks. Proposed management actions include determination and implementation of Environmental Flow Reserves in stressed systems, management of existing alien fish populations and prevention of new establishments, and regular assessments of fish communities.

Do protected areas conserve neotropical freshwater fishes? A case study of a biogeographic province in Venezuela

The effectiveness of protected areas to conserve freshwater fishes is limited because these areas are not usually congruent with regional patterns of fish species richness and distribution. We compared the richness, distribution and abundance of coastal freshwater fishes in a biogeographic province of Venezuela to determine their conservation status. We also estimated the relevance of existing protected areas in conserving fishes in different physiographic units and tributaries by evaluating species richness and distribution. The ichthyofauna (72 spp., ~30% endemic, ~10% threatened) was distributed according to orography, drainage and physiographic units. Most protected areas had limited effectiveness for fish conservation, mainly because they were too small or included only fragments of tributaries or drainages, or because they were located only in highland drainages where species diversity was minimal. To adequately protect freshwater fishes in this province the existing protected areas should be modified and expanded.

Freshwater Fish Abundance and Distribution in the Orange River, South Africa

Freshwater Fish Abundance and Distribution in the Orange River, South Africa

Additional records of non-native freshwater fishes for the Ebro River basin (Spain)

This paper extends the knowledge of the geographical distribution of non-native freshwater fishes in the Ebro River basin (Spain). More than two hundred surveys were carried out since 2000, and thirteen non-native fish species were collected on fifty- eight occasions. The spread of most of the recorded non-native species seems to be a consequence of illegal introductions related to sport fishing activities and the subsequent natural dispersal. Their presence could impact natural populations of Iberian native -mostly endemic- freshwater fish species, through direct predation and competition for niche and/or trophic resources.

Introduction and distribution of alien freshwater fishes on the island of Sardinia (Italy): an assessment on the basis of existing data sources

Summary Data on the occurrence and distribution of alien freshwater fishes in Sardinia are provided based on historical data and recent reports. A total of 14 introduced fish species are established in Sardinian fresh waters. These species comprise members of the Cyprinidae (carp, Cyprinus carpio; tench, Tinca tinca; goldfish, Carassius auratus; rudd, Scardinius erythrophthalmus; bleak, Alburnus alburnus alborella), Centrarchidae (pumpkinseed, Lepomis gibbosus; largemouth bass, Micropterus salmoides), Salmonidae (rainbow trout, Oncorhynchus mykiss; brown trout, Salmo trutta), Cobitidae (spined loach, Cobitis taenia), Ictaluridae (black bullhead, Ameiurus melas), Percidae (European perch, Perca fluviatilis), and Poeciliidae (mosquitofish, Gambusia holbrooki). The species most recently introduced into Sardinia is the topmouth gudgeon, Pseudorasbora parva (Cyprinidae). The majority of alien fishes documented here match those that have already established self-maintaining populations elsewhere in Mediterranean-type eco-regions. Since the late nineteenth century, fish identified as potential sources of food have been introduced for aquaculture and stock enhancement purposes. Other introductions have subsequently occurred for the purposes of biological control, ornamental use or sport fishing activities. Some species are notably widespread and common (e.g. mosquitofish and tench), whereas the presence of others seems to be more restricted and may still be confined to a few hydrographic regions (e.g. bleak, rudd, pumpkinseed and topmouth gudgeon).

Geographical distribution of genuine freshwater fishes in Fukuoka Prefecture, northern Kyushu, Japan

Geographical distribution of genuine freshwater fishes in Fukuoka Prefecture, northern Kyushu, Japan

Diversity and Distribution of Freshwater Fishes in Aceh Water, Northern-Sumatra, Indonesia

Diversity and Distribution of Freshwater Fishes in Aceh Water, Northern-Sumatra, Indonesia

Nuclear and mitochondrial DNA sequence data reveal the evolutionary history of Barbus (Cyprinidae) in the ancient lake systems of the Balkans

Freshwater fauna of ancient lakes frequently contain endemic taxa thought to have originated during the long existence of these lakes, yet uncertainties remain as to whether they represent distinct genetic lineages with respect to more widespread relatives and to the relative roles of isolation and dispersal in their evolution. Phylogenetic analyses of sequence variation at nuclear and mitochondrial genes were used to examine these issues for the freshwater fish genus Barbus in two European ancient lake systems on the Balkan Peninsula. The nuclear and mitochondrial data yielded concordant phylogeographic patterns though incomplete sorting of nuclear haplotypes between some mitochondrial clades was detected. The distributions of two currently recognized species investigated here do not match the distributions of evolutionary lineages revealed by phylogenetic analyses. The Prespa barbel, Barbus prespensis, is not endemic to the lakes Prespa as previously thought but is instead found to be widespread in the south-eastern Adriatic Sea basin, with a distribution largely corresponding to the basin of the now extinct Lake Maliq historically connected with Lake Prespa. On the other hand, a cryptic phylogenetic subdivision in a widespread species, B. rebeli, was discovered to be more distant from B. rebeli than from other Barbus species and to be endemic to the system of connected lakes Ohrid and Shkodra. The division coincides with the hydrogeographical boundary delimiting distributions of other freshwater fishes, and we suggest that this newly discovered evolutionary lineage represents a distinct species. These findings support the emerging pattern that endemic taxa have evolved not through isolation of individual lakes, but in systems of currently and historically interconnected lakes and their wider basins.

Annotated checklist of the freshwater fishes of continental and insular Honduras

The freshwater fishes of Honduras were surveyed for a period of four years (2005–2008). Surveys were supplemented with both literature and museum collection reviews. Our results show that there are at least 172 species of fishes inhabiting Honduran mainland and insular freshwater systems, 166 native and six exotic. Primary freshwater fish diversity was low, with only eigth species (4.8%). The remaining species were either secondary freshwater (47 species, 28.3%) or peripheral (111 species, 66.9%). This checklist includes 36 new records for Honduras, and 12 range expansions. Nine species were found to be endemic; however, just two of them (Amphilophus hogaboomorum and Theraps wesseli) are already described. The depauperate primary freshwater fishes fauna of Honduras (8) is congruent with low primary freshwater fishes diversity found in the region between the Usumacinta River and the Nicaraguan great lakes. Although many previously unsampled regions of Honduras were visited as part of this project, there are a variety of remote areas that remain unstudied. While this paper contributes much to the understanding of the distribution and diversity of Honduran freshwater fishes, it is likely that much diversity there remains undocumented.

Molecular and karyotypic phylogeography in the NeotropicalHoplias malabaricus(Erythrinidae) fish in eastern Brazil

The sedentary, predatory characin Hoplias malabaricus has one of the widest distributions of freshwater fishes in South America and is characterized by seven karyomorphs (A-G) that occur in sympatric and allopatric populations. Karyotypical patterns of variation in wild populations have been interpreted as evidence of multiple lineages within this nominal species, a possibility that may limit the validity of experimental data for particular karyomorphs. This study used the phylogeographic and genealogical concordance between cytogenetic (N = 49) and molecular (mitochondrial DNA) (N = 73) data on 17 samples, collected in 12 basins from south-eastern and north-eastern Brazil, to assess the systematic value of cytogenetic data. Cytogenetic patterns show a sex chromosome system in the 2n = 40F karyomorph. Molecular and cytogenetic data indicate a long, independent evolutionary history of karyomorphs and a coastal origin of continental populations in south-eastern Brazil. The lack of fit with molecular clock expectations of divergence between groups is likely to be due to strong demographic fluctuations during the evolution of this species complex. The results indicate that karyotypical identification provides a reliable baseline for placing experimental studies on Hoplias spp. in a phylogenetic context.