Rhodeus Amarus Research Articles

High cryptic diversity of bitterling fish in the southern West Palearctic

South-east Europe, along with the adjacent region of south-west Asia, is an important biodiversity hotspot with high local endemism largely contributed by contemporary continental lineages that retreated to southern refugia during colder Quaternary periods. We investigated the genetic diversity of the European bitterling fish (Rhodeus amarus) species complex (Cyprinidae) across its range in the western Palearctic, but with a particular emphasis in the region of Balkan, Pontic and Caspian refugia. We genotyped 12 polymorphic microsatellite loci and a partial sequence of mitochondrial gene cytochrome b (CYTB) for a set of 1,038 individuals from 60 populations. We used mtDNA sequences to infer phylogenetic relationships and historical demography, and microsatellite markers to describe fine-scale genetic variability and structure. Our mtDNA analysis revealed six well-supported lineages, with limited local co-occurrence. Two lineages are distributed throughout central and western Europe (lineages “A” and “B”), with two zones of secondary contact. Another two lineages were restricted to the Ponto-Aegean region of Greece (lineages “C” and “D”) and the final two lineages were restricted south of the Caucasus mountains (lineage “E” from the Black Sea watershed and lineage “F” from the Caspian watershed). A signal of recent expansion was revealed in the two widespread lineages and the Ponto-Aegean lineage “C”. The geographic distribution of clusters detected by nuclear microsatellites corresponded well with mitochondrial lineages and demonstrated finely sub-structured populations. A profound population structure suggested a significant role of genetic drift in differentiation among lineages. Lineage divergence in the Ponto-Aegean and Caspian regions are substantial, supporting the validity of two described endemic species (Rhodeus meridionalis as lineage “D” and Rhodeus colchicus as lineage “E”) and invite taxonomic evaluation of the other two southern lineages (Thracean “C” and Caspian “F”).

Host fish status of native and invasive species for the freshwater mussel Anodonta anatina (Linnaeus, 1758)

The worldwide extinction of species especially affects freshwater ecosystems. Even widespread species like the European freshwater duck mussel Anodonta anatina face population declines in many countries and regions. Due to an obligate parasitic phase in its life cycle, knowledge on host fish use is essential for effective conservation of A. anatina. Therefore, in this study host suitability of ten different fish species (native and invasive to Europe) from four different fish families was tested by simultaneously infesting them with the glochidia of A. anatina. Nine out of ten fish species were identified as suitable hosts, but infestation rates, duration of metamorphosis phase as well as duration and rate of juvenile mussel excystment differed significantly between all host species. The bitterling (Rhodeus amarus) was the only fish species with no juvenile mussel excystment. Surprisingly, one of the tested invasive fish (Ctenopharyngodon idella) turned out to be the second best host for the larvae of A. anatina, suggesting that the general assumption that non-native fishes would be a threat to native mussel populations no longer holds true. Compared to the second native Anodonta species in Europe (Anodonta cygnea), this study revealed that A. anatina had higher infestation rates and rates of juvenile mussels excystment as well as a different host compatibility than A. cygnea. These findings illustrate that species-specific assessments of host suitability form an urgent basis for evidence-based conservation and restoration of freshwater mussel populations and the ecosystem services they provide.

Length-weight and length-length relationships of the European bitterling, Rhodeus amarus (Bloch, 1782) inhabiting inland waters of Samsun Province

In this study, length-weight relationships (LWRs) and length-length relationships (LLRs) for Rhodeus amarus sampled from the Terme and Terice Streams were calculated in April-November 2016. A total of 117 fish specimens (from Terme = 57, from Terice= 60) were examined. Total, fork and standard length were measured (±0.1 cm) and weighted (±0.01 g) for all captured fish. Total length varies between 4.5 and 8.9 cm, weight varies between 0.730-9.940 g for all populations. Length-weight equations were calculated as W=0.005TL3.479 and W=0.004TL3.586 for Terme and Terice, respectively. According to analyses bitterling has positive allometric growths for two localities. Length-length relationships equations show that total, fork and standard length values are very strong between each other (P<0.001, coefficient of determination >0.95).

Fine-scale genetic structure of the European bitterling at the intersection of three major European watersheds

BackgroundAnthropogenic factors can have a major impact on the contemporary distribution of intraspecific genetic diversity. Many freshwater fishes have finely structured and locally adapted populations, but their natural genetic structure can be affected by river engineering schemes across river basins, fish transfers in aquaculture industry and conservation management. The European bitterling (Rhodeus amarus) is a small fish that is a brood parasite of freshwater mussels and is widespread across continental Europe. Its range recently expanded, following sharp declines in the 1970s and 1980s. We investigated its genetic variability and spatial structure at the centre of its distribution at the boundary of three watersheds, testing the role of natural and anthropogenic factors in its genetic structure.ResultsSequences of mitochondrial cytochrome B (CYTB) revealed that bitterling colonised central Europe from two Ponto-Caspian refugia, which partly defines its contemporary genetic structure. Twelve polymorphic microsatellite loci revealed pronounced interpopulation differentiation, with significant small-scale differentiation within the same river basins. At a large scale, populations from the Baltic Sea watershed (middle Oder and Vistula basins) were distinct from those from the Black Sea watershed (Danube basin), while populations from rivers of the North Sea watershed (Rhine, Elbe) originated from the admixture of both original sources. Notable exceptions demonstrated the potential role of human translocations across watersheds, with the upper River Oder (Baltic watershed) inhabited by fish from the Danube basin (Black Sea watershed) and a population in the southern part of the River Elbe (North Sea watershed) basin possessing a signal of admixture from the Danube basin.ConclusionsHydrography and physical barriers to dispersal are only partly reflected in the genetic structure of the European bitterling at the intersection of three major watersheds in central Europe. Drainage boundaries have been obscured by human-mediated translocations, likely related to common carp, Cyprinus carpio, cultivation and game-fish management. Despite these translocations, populations of bitterling are significantly structured by genetic drift, possibly reinforced by its low dispersal ability. Overall, the impact of anthropogenic factors on the genetic structure of the bitterling populations in central Europe is limited.

Morphological characteristics, reproduction, and food habits of European bitterling Rhodeus sericeus amarus (Cyprinidae) in the Alatyr River

The data on the morphology, reproduction, and diet of European bitterling Rhodeus sericeus amarus in the Alatyr River (the Sura tributary) are presented. Differences between females and males have been revealed with respect to the complex of morphometric characters. It is assumed that the deviations of some meristic characters from those that are typical of European bitterling are due to the habitation of this population at the boundary of the species distribution. The species reaches sexual maturity at the age of 1–2 years; the individual fecundity is 103–525 (354) eggs. Bitterling is a typical phytophage.

Improving Upstream and Downstream Fish Passage at Retis Dam on Hârtibaciu River - Sibiu County (Transylvania)

Abstract Retis (dam Retis), hydro-technical development like many other transverse hydraulic structures cancel the longitudinal connectivity of Hârtibaciu water course, blocking the migration of different (migrating) species of fish in the river. Also, the lateral connectivity was heavily affected on this water course at a rate of 60%. Therefore, proposing engineering solutions to recover both (lateral and longitudinal) types of connectivity is vital to restore the local ecobiom. The purpose of this article is to establish longitudinal connectivity through an engineering solution that facilitates the fish migration upstream - downstream of Retis dam. This paper proposes an engineered fish passage solution for Retiș Dam on the Hârtibaciu River, using the criteria described in the Water Framework Directive 2000/60/EC document. Anthropogenic barriers located in the Hârtibaciu River disrupt and delay movement of local fish fauna including: Alburnoides bipunctatus (Bloch, 1782), Squalius cephalus (Linnaeus, 1758), Alburnus alburnus (Linnaeus, 1758), Rhodeus amarus (Bloch, 1782), Gobio gobio (Linnaeus, 1758), Romanogobio kessleri (Dybowski, 1862), Barbatula barbatula (Linnaeus, 1758), Barbus meridionalis Risso, 1827 Misgurnus fossilis (Linnaeus, 1758), Cobitis taenia Linnaeus, 1758, Cobitis romanica (Băcescu, 1943), and Cobitis aurata (De Filippi, 1863).

Sex differences in the responses to oviposition site cues by a fish revealed by tests with an artificial host

Oviposition decisions can have important fitness consequences for offspring. We investigated the responses of European bitterling, Rhodeus amarus , a freshwater fish that spawns in the gills of living unionid mussels, to oviposition site cues. Using an artificial mussel, we manipulated the flow velocity, dissolved oxygen concentration and odour cues of mussels presented to pairs of R. amarus . Females responded positively to mussel odour and to dissolved oxygen cues. Male response was dependent on mussel odour and the flow velocity of water emerging from the artificial mussel. These responses are potentially adaptive, with females responding to cues that indicate the quality of oviposition sites for incubation of eggs. Males responded to cues with implications for optimal sperm allocation.

Glochidial development of the freshwater swan mussel (Anodonta cygnea, Linnaeus 1758) on native and invasive fish species

The declining mussel Anodonta cygnea is an important keystone species in European freshwater systems. Information on the complex life cycle of A. cygnea regarding the attachment and metamorphosis of their larvae on suitable host fish species is lacking, yet important as a basis for conservation and fisheries management. Ten different fish species, including eight native and two non-native species from four different families, were simultaneously infested with the glochidia of A. cygnea in a standardized laboratory experiment. The results of this study confirmed the hypothesis that Anodonta cygnea can be considered a host generalist, as nine out of the ten tested fish species were suitable hosts, and different body parts were infested. Due to the observed differences in initial infestation rates and metamorphosis success, hosts were classed into “good hosts” (Perca fluviatilis, Leuciscus idus, Salmo trutta, Gasterosteus aculeatus, Ctenopharyngodon idella), “poor hosts” (Leucaspius delineatus, Gobio gobio, Rutilus rutilus, Pseudorasbora parva) and “not hosts” (Rhodeus amarus). The larval development differed strongly between the single host fish species with regard to success and duration of metamorphosis, as well as timing and synchronization in larval drop-off, suggesting evolutionary consequences of the use of different host fish species. The finding that two non-native fish species were identified as suitable hosts for the glochidia of A. cygnea illustrates that the generalizations that non-native species are a threat to native mussel communities and that co-evolutionary patterns between hosts and mussels determine host suitability do not always hold true.

Assessing the ecological impacts of invasive species based on their functional responses and abundances

Invasive species management requires allocation of limited resources towards the proactive mitigation of those species that could elicit the highest ecological impacts. However, we lack predictive capacity with respect to the identities and degree of ecological impacts of invasive species. Here, we combine the relative per capita effects and relative field abundances of invader as compared to native species into a new metric, “Relative Impact Potential” (RIP), and test whether this metric can reliably predict high impact invaders. This metric tests the impact of invaders relative to the baseline impacts of natives on the broader ecological community. We first derived the functional responses (i.e. per capita effects) of two ecologically damaging invasive fish species in Europe, the Ponto-Caspian round goby (Neogobius melanostomus) and Asian topmouth gudgeon (Pseudorasbora parva), and their native trophic analogues, the bullhead (Cottus gobio; also C. bairdi) and bitterling (Rhodeus amarus), towards several prey species. This establishes the existence and relative strengths of the predator–prey relationships. Then, we derived ecologically comparable field abundance estimates of the invader and native fish from surveys and literature. This establishes the multipliers for the above per capita effects. Despite both predators having known severe detrimental field impacts, their functional responses alone were of modest predictive power in this regard; however, incorporation of their abundances relative to natives into the RIP metric gave high predictive power. We present invader/native RIP biplots that provide an intuitive visualisation of comparisons among the invasive and native species, reflecting the known broad ecological impacts of the invaders. Thus, we provide a mechanistic understanding of invasive species impacts and a predictive tool for use by practitioners, for example, in risk assessments.

The endangered thick-shelled river mussel (Unio crassus): a new host species for the European bitterling (Rhodeus amarus)

Large freshwater mussels (Unionoida) are declining throughout the world. The European bitterling Rhodeus amarus (Bloch, 1782) female spawns its eggs inside the unionids’ shells, where fertilisation and further embryonic development take place; thus its reproduction depends fully on the presence of large freshwater mussels. Unio crassus, previously regarded as one of the most numerous unionids in Europe, is now listed in the IUCN Red Data List as being globally endangered. Despite its previous prevalence, it was never reported as a host for the bitterling. A large population of U. crassus was studied in small river at the Świętokrzyskie Mts (Poland), where also electrofishing was conducted. In each bitterling territory located on the study plots, we found individuals of U. crassus, with the bitterling eggs or larvae developing on mussel’s gills. That proves that this species can be also used by the bitterling for reproduction. We suggest that this relationship has not been reported to date due to the mussels’ rarity and ongoing decline. However, it is also possible that the endangered mussel is a novel host for the bitterling, which is expanding its range throughout Europe.

No effect of recent sympatry with invasive zebra mussel on the oviposition decisions and reproductive success of the bitterling fish, a brood parasite of unionid mussels

The presence of non-native species can affect coevolved relationships. However, rapid reciprocal changes in coevolutionary associations provide the potential to quickly respond to a new situation. We studied a system where bitterling fish (Rhodeus amarus) parasitize unionid mussels by laying their eggs onto their gills. This association is affected by the infestation of unionid shells by the non-native zebra mussel (Dreissena polymorpha). In a series of experiments under experimental, semi-natural and natural conditions, we compared the behavioural response to zebra mussel infestation of unionid shells, its effect on oviposition decisions and their population consequences between bitterling populations naive to zebra mussels and those recently sympatric with zebra mussels. We found no effect of recent sympatry on bitterling preoviposition behaviour and oviposition decisions and only a weak effect on their reproductive success. Bitterling from both populations inspected infested and non-infested mussels at the same rate but preferred to oviposit into non-infested unionid hosts. However, neither bitterling population completely avoided oviposition into infested unionids and three ovipositions into zebra mussels were observed. Overall, there was a clear negative relationship between the number of zebra mussels on unionid host shells and the number of juvenile bitterling emerging from the mussels. Our study demonstrated a lack of rapid evolutionary response to adaptively modulate oviposition choice after recent zebra mussel invasion.

Methodological issues affecting the study of fish parasites. III. Effect of fish preservation method.

The aim of this study was to evaluate the influence of preservation method on the results of parasite community studies. Two host species, European perch Perca fluviatilis and European bitterling Rhodeus amarus, were examined for parasites after having been subjected to 4 different storage treatments: freezing, preservation in 4% formaldehyde or 70% ethanol and transportation of live (fresh) fish as a control. Preservation prior to dissection resulted in a loss of information, leading to incomplete quantitative data (all preservation treatments), qualitative data (ethanol and formaldehyde preservation) and a lowered ability to determine parasites to species level based on morphology compared to dissecting fresh fish. Of the more abundant taxa, only crustaceans and acanthocephalans provided relatively even results between treatments. We conclude that preservation media, such as ethanol or formaldehyde, significantly affects the ability to obtain precise parasite community data; hence, we recommend the use of freshly sacrificed fish for parasite community studies whenever possible. Alternatively, freezing may prove acceptable for evaluating parasite community taxonomic composition.

Bayesian inference supports the host selection hypothesis in explaining adaptive host specificity by European bitterling

Generalist parasites have the capacity to infect multiple hosts. The temporal pattern of host specificity by generalist parasites is rarely studied, but is critical to understanding what variables underpin infection and thereby the impact of parasites on host species and the way they impose selection on hosts. Here, the temporal dynamics of infection of four species of freshwater mussel by European bitterling fish (Rhodeus amarus) was investigated over three spawning seasons. Bitterling lay their eggs in the gills of freshwater mussels, which suffer reduced growth, oxygen stress, gill damage and elevated mortality as a result of parasitism. The temporal pattern of infection of mussels by European bitterling in multiple populations was examined. Using a Bernoulli Generalized Additive Mixed Model with Bayesian inference it was demonstrated that one mussel species, Unio pictorum, was exploited over the entire bitterling spawning season. As the season progressed, bitterling showed a preference for other mussel species, which were inferior hosts. Temporal changes in host use reflected elevated density-dependent mortality in preferred hosts that were already infected. Plasticity in host specificity by bitterling conformed with the predictions of the host selection hypothesis. The relationship between bitterling and their host mussels differs qualitatively from that of avian brood parasites.

Proposal to Achieve Floodplain Connectivity in Alțâna Sector on Hârtibaciu River (Transylvania, Romania)

Abstract The process of supplying water to the new anthropogenic wetland is achieved gravitationally, and the excess water in the wetland will be directed towards the Hârtibaciu River in a similar natural way. The fish and fauna of the Hârtibaciu River have a disrupted lateral connectivity due to its banks embanking including in the proximity of the Alţâna locality. The newly proposed anthropogenic wetland would improve habitat quality for the fish species of conservation interest, Rhodeus amarus (Bloch, 1782), and increase its population numbers. A new fish species, Chondrostoma nasus, was identified for the first time in the Hârtibaciu River.

Proposing a Technical Solution for Restoring Longitudinal Connectivity in the Brădeni/Retiş Accumulation Area on Hârtibaciu River

Abstract The fish fauna of the Hârtibaciu River has experienced a disrupted connectivity due to the hydrotechnical works and the Brădeni/Retiş Dam located across the Hârtibaciu watercourse being one of this significant obstacles. The newly proposed constructed wetlands can improve the habitat quality for the fish species of conservative interest sampled in the Brădeni/Retiş Dam proximity Rhodeus amarus, and can increase the individuals’ number of this population. Also can benefit the local populations of Phoxinus phoxinus and Gobio obtusirostris. Using gravitational force and also the underground layout, a proposed technical solution gives maximum safety regarding the water supply for the newly proposed to be created wetlands.

The distribution of an invasive fish species is highly affected by the presence of native fish species: evidence based on species distribution modelling

Topmouth gudgeon (Pseudorasbora parva) is one of the most invasive aquatic fish species in Europe and causes adverse effects to ecosystem structure and functioning. Knowledge and understanding of the species’ interactions with the environment and with native fish are important to stop and prevent the further spread of the species. Creating species distribution models is a useful technique to determine which factors influence the occurrence and abundance of a species. We applied three different modelling techniques: general additive models, random forests and fuzzy habitat suitability modelling (FHSM) to assess the habitat suitability of topmouth gudgeon. The former two techniques indicated that the abundance of native fish (i.e. biotic variables) was more important than environmental variables when determining the abundance of topmouth gudgeon in Flanders (Belgium). Bitterling (Rhodeus amarus), stone loach (Barbatula barbatula), three-spined stickleback (Gasterosteus aculeatus) and predator abundance were selected as the most important biotic variables and implemented in the FHSM to investigate species interactions. Depending on the preferred food source and spawning behaviour, either coexistence or interspecific competition can occur with bitterling, stone loach and three-spined stickleback. In contrast, the presence of predators clearly had a top down effect on topmouth gudgeon abundance. These findings could be applied as a biological control measure and implemented in conservation strategies in order to reduce the abundance of earlier established populations of topmouth gudgeon.

Population-specific responses to an invasive species.

Predicting the impacts of non-native species remains a challenge. As populations of a species are genetically and phenotypically variable, the impact of non-native species on local taxa could crucially depend on population-specific traits and adaptations of both native and non-native species. Bitterling fishes are brood parasites of unionid mussels and unionid mussels produce larvae that parasitize fishes. We used common garden experiments to measure three key elements in the bitterling-mussel association among two populations of an invasive mussel (Anodonta woodiana) and four populations of European bitterling (Rhodeus amarus). The impact of the invasive mussel varied between geographically distinct R. amarus lineages and between local populations within lineages. The capacity of parasitic larvae of the invasive mussel to exploit R. amarus was higher in a Danubian than in a Baltic R. amarus lineage and in allopatric than in sympatric R. amarus populations. Maladaptive oviposition by R. amarus into A. woodiana varied among populations, with significant population-specific consequences for R. amarus recruitment. We suggest that variation in coevolutionary states may predispose different populations to divergent responses. Given that coevolutionary relationships are ubiquitous, population-specific attributes of invasive and native populations may play a critical role in the outcome of invasion. We argue for a shift from a species-centred to population-centred perspective of the impacts of invasions.

Fish fauna of the Oster River basin (Desna River basin, Ukraine) – recent data

According to recent data, fish fauna of the Oster River basin numbers 21 species, including two introduced species: Perccottus glenii and Pseudorasbora parva . 17 species of fish were registered in the lower section of the river (4 of them for the first time), 21 species were found in the middle section (12 of them were not previously noted for this section) and only 11 species were found in the upper section (6 species were not previously noted for this section). Six species – Pseudorasbora parva , Misgurnus fossilis , Pungitius platygaster , Gymnocephalus cernu a , Babka gymnotrachelus and Protero­rhinus semilunaris – are recordered in the Oster River for the first time. Fish population of the lower part differs by qualitative composition, primarily due to its link with the Desna River. Only 11 species were registered in three tributaries of the Oster River and in their basins. Nosivochka River has 6 species, including introduced Cyprinus carpio and Hypophthalmichthys molitrix . Five species were recorded in the Divytsia River basin and six species are found in the V’iunnytsia River. The most frequently caught species in the Oster River basin were Leucaspius delineatus and Rhodeus amarus (F = 75.0), Scardinius erythr ophthalmus and Tinca tinca (F = 66.7). Keywords : Ukraine, Oster River, Desna River, ichthiofauna, introduced species.

Length–Weight Relationships for Freshwater Fish Species in Küçük Menderes River Basin, Turkey

Event Abstract Back to Event Length–Weight Relationships for Freshwater Fish Species in Küçük Menderes River Basin, Turkey Mustafa Korkmaz1, 2*, Fatih Mangıt1 and Sedat V. Yerli1 1 Hacettepe University, Department of Biology, Türkiye 2 University of Ağrı İbrahim Çeçen, Department of Biology, Türkiye This study provides length–weight relationships for ten fish species from Küçük Menderes River Basin, inland water systems of Western Anatolian Region, Turkey. Samples were collected from six different localities, three reservoirs and three streams, in Küçük Menderes River Basin. The samples were collected using multimesh gillnets in reservoirs and electrofishing with ‘SAMUS 725-MP’ in rivers and fixed in formalin (4%). Identification of the fish species were done according to literature. Specimens of ten species belonging to three families were analyzed. The exponent b in the length-weight relationship ‘W=a(TL)b’ ranged from 2.54 to 3.52. The length-weight relationships for Barbus pergamonensis, Carassius carassius, Carassius gibelio, Chondrostoma holmwoodii, Cyprinus carpio, Gambusia affinis, Perca fluviatilis, Petroleuciscus smyrnaeus, Squalius kosswigi and Rhodeus amarus were given in this study. Information of length–weight relationships will be useful for researchers especially in conservation. Acknowledgements Authors thanks to Republic of Turkey Ministry of Forestry and Water Affair, General Directorate of Water Management and Segal Environmental Measurement and Analysis Laboratory for their financial supports. Keywords: fish, length–weight relationship, Turkey., Fresh Water, Anatolia Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Poster Presentation Topic: Physiology, Behavior and Toxicology Citation: Korkmaz M, Mangıt F and Yerli S (2015). Length–Weight Relationships for Freshwater Fish Species in Küçük Menderes River Basin, Turkey. Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.FMARS.2015.03.00167 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 25 Oct 2015; Published Online: 28 Nov 2015. * Correspondence: Dr. Mustafa Korkmaz, Hacettepe University, Department of Biology, Ankara, Türkiye, korkmaz.bio@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Mustafa Korkmaz Fatih Mangıt Sedat V. Yerli Google Mustafa Korkmaz Fatih Mangıt Sedat V. Yerli Google Scholar Mustafa Korkmaz Fatih Mangıt Sedat V. Yerli PubMed Mustafa Korkmaz Fatih Mangıt Sedat V. Yerli Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

LENGTH-WEIGHT RELATIONSHIPS OF FISH SPECIES IN MARMARA LAKE, WEST ANATOLIA, TURKEY

The study reports on length–weight relationships (LWRs) for 13 fish species (Atherina boyeri, Cobitis fahirae, Alburnus battalgilae, Cyprinus carpio, Carassius gibelio, Ladigesocypris mermere, Pseudorasbora parva, Petroleuciscus smyrnaeus, Rhodeus amarus, Vimba vimba, Sander lucioperca, Gambusia affinis, Knipowitschia mermere) of 6 families in Marmara Lake, which is an alluvial set lake in west Anatolia, Turkey. Fish were caught between March 2012 and February 2013 with trammel nets and gillnets. The length– weight relationship was calculated using the expression: log (W) = log (a) + b log (L). Parameters of LWR are computed as “ a” ranging from 0.0053 to 0.0385, “ b” from 2.346 to 3.429, and “ r 2” from 0.814 to 0.994. Growth types were determined to be isometric, positive allometric and negative allometric for 4, 4 and 5 species, respectively. In addition, the present study includes first records of LWR for two endemic and two native species in freshwater of Turkey. The results would be useful for the protection of the presence of endemic species and sustainable fisheries in the lake.