Reproductive parameters of invasive topmouth gudgeon Pseudorasbora parva (Temminck and Schlegel, 1846) from Slovakia

Females of an invasive population of topmouth gudgeon Pseudorasbora parva (Temmick and Schlegel, 1846) from the Šúr pond (Bratislava, Slovakia) were examined to analyze their fecundity and other life history traits. Samples were collected during both pre-spawning (n = 137) and post-spawning (n = 89) periods. Standard length of the females from the pre-spawning period ranged from 23.42 to 59.71 mm (mean 32.80 mm), body weight from 0.260 to 5.442 g (mean 0.965 g), and eviscerated body weight from 0.207 to 4.882 g (mean 0.748 g). Absolute fecundity varied between 121 and 7124 oocytes (mean 1106 oocytes). In 75.22% of the females, two or three size groups of oocytes were clearly distinguished. Overall, the life history traits observed in invasive topmouth gudgeon from the Šúr pond demonstrated a high flexibility in their reproductive strategy. This, together with previously described great morphological variability, is likely to make this species such a successful invader.     

Length–weight relationships of two fish species from Gamsiab Reservoir,western Iran: Alburnus mossulensis Heckel, 1843 and Luciobarbus esocinus Heckel, 1843

In this study the length–weight relationships (LWRs) for two fish species, Alburnus mossulensis and Luciobarbus esocinus, were analyzed based on seasonal samplings from 2013 and 2014. The specimens were collected by cast‐ and dip net from the Karun River Basin in the Zagros Mountains, Iran. The b values in the LWRs were determined as 2.9996 for A. zagrosensis and 2.6546 for L. esocinus.     

Length‐weight and length‐length relationships of Oxynoemacheilus frenatus (Heckel, 1843) and Petroleuciscus esfahani Coad & Bogutskaya, 2010 from the Cheshmeh‐Langan river,Iran

The study presents length‐weight relationships (LWRs) and length‐lenght relationships (LLRs) for two freshwater fish species from the Cheshmeh‐Langan River (Iran; 32°50′N, 50°04′E), a part of the Tigris drainage basin. Fish were sampled by electrofishing (Samus 725M) in August and September 2017. The LWRs and LLRs obtained showed a high level of correlation (r² > .98).     

Length–weight and length–length relationships of three cyprinid fishes from the Bibi‐Sayyedan River,western Iran

This study describes the length–weight and length–length relationships for three cyprinid species from the Bibi‐Sayyedan River (western Isfahan provinces, Iran). The slope parameter (b) values in the length–weight relationship equations were determined as 3.0729 for Alburnus mossulensis Heckel, 1843; 2.8509 for Barbus lacerta Heckel, 1843; and 3.0864 for Chondrostoma regium (Heckel, 1843). This study presents the first LWR and LLR references for these species in the Bibi‐Sayyedan River.     

Length–weight and length–length relationships for eight fish species from the Jarrahi River,southwestern Iran

Length–weight and length–length relationships were estimated for eight fish species belonging to three families from the Jarrahi River in southwestern Iran. The study was performed between June 2009 and September 2011. Weight–length relationships were estimated using the logarithmic form of the equation W = aL^b. The b values varied between 2.96 and 3.61 and determined as 3.42 for Alburnus mossulensis Heckel, 1843; 3.33 for Alburnoides idignensis Bogutskaya and Coad, 2009; 2.85 for Barbus grypus Heckel, 1843; 3.61 for Barilius mesopotamicus Berg, 1932; 3.16 for Cyprinion kais (Heckel, 1843); 3.36 for Cyprinion macrostomum Heckel, 1843; 3.27 for Paraschistura nielseni (Nalbant and Bianco, 1998); and 2.96 for Glyptothorax silviae Coad, 1981. This study presents the first LWR and LLR references for these species in the Jarrahi River.     

Length–weight and length–length relationships of three fish species (Cyprinidae) from Chahnimeh reservoirs,Zabol, in eastern Iran

Length–weight (LWR) and length–length (LLR) relationships was estimated for three fish species collected in Chahnimeh reservoirs located in the city of Zabol, Iran. The values of the parameter slope (b) in the length–weight relationship were determined 2.45 for Crossocheilus latius, 2.97 for Schizocypris altidorsalis and 3.14 for Schizothorax zarudnyi. The relationships between TL, FL and SL were all linear (for all cases: r² > 0.93).     

Length–weight and length–length relationships for three species of Squalius (Cyprinidae; Leuciscinae) from the Caspian Sea,Namak and Tigris basins of Iran

Length‐weight and length‐length relationships were estimated for three species of the genus Squalius. These fish were sampled from the Caspian Sea as well as the Namak and Tigris basins of Iran. Sampling took place between July 2009 and August 2010 using a seine net (15 m long, 2 m width and 5 mm mesh size). The values of the b parameter in the length‐weight relationship equations were determined as 3.37 for S. turcicus, 3.25 for S. namak and 3.14 for S. berak (b > 3).     

Length–weight and length–length relationships for four fish species from Talkhehrud River,Urmia Lake basin,Iran

Length–weight and length–length parameters were calculated in the Talkhehrud River, northwestern Iran, for four freshwater fish species belonging to two families. The b values varied between 2.27 and 3.19, with a mean ± SD of 2.2777 ± 0.387. The b parameter values in the length–weight relationship equations were determined as 2.73 for Alburnus atropatenae Berg, 1925; 3.19 for Alburnoides petrubanarescui Bogutskaya & Coad, 2009; 2.92 for Capoeta capoeta (Güldenstädt, 1773); and 2.27 for Oxynoemacheilus persa (Heckel, 1847). This study provides the first reference on the LWRs and LLRs for these species in the Talkhehrud River.     

Length–weight and length–length relationships for cavedano chub Squalius squalus (Bonaparte, 1837) in Italy

Data of 31496 specimens of cavedano chub Squalius squalus were collected in 89 different waterbodies distributed geographically throughout Italy and used to provide length–weight and length–length relationship for this species. The linear relationship between total length (TL) and standard length (SL) was described by the equation TL (cm) = 4.007 + 0.874 SL (cm). The resulting total length–weight equation for cavedano chub in Italy was: log₁₀ W = ?2.121 + 3.083 log₁₀ TL (cm).     

Length–weight relationships and length–length relationships of 13 fish species in Rongcheng Bay,China

The present study provides the length–weight relationships (LWRs) of 13 fish species belonging to eight families that were collected in Rongcheng Bay, March 2009 to December 2014. The r² values ranged from 0.953 to 0.994 and values of b varied from 2.542 to 3.454. The study also describes the total length – standard length relationships (LLRs) for these fish species. This is the first record of length–weight and length–length relationships for the fish species in this area.     

Length–weight and length–length relationships for four shad species along the western Black Sea coast of Turkey

This study investigates length–weight and length–length relationships of four shad species (Alosa caspia caspia, Alosa immaculata, Alosa maeotica, Alosa tanaica) captured in the western Black Sea coast of Turkey. A total of 686 specimens, 355 females and 331 males, were caught by gill net, trammel net and longline from 2006 through 2007 along the western Black Sea coast of Turkey. The relationships of total length (TL), fork length (FL) and standard length (SL) are presented for inhabiting in the Black Sea four shad species and the relationships between total length (TL) and body weight (BW) from the two localities, Sile and Karasu in the western Black Sea coast of Turkey. The Length–weight relationships generally indicated positive allometric growth in Alosa species for both males and females and an isometric growth for A. immaculata females. The coefficient b ranged from a minimum 2.97 for females of A. immaculata to a maximum 3.75 for both sexes A. c. caspia. Results indicated that the length–length relationship between the three length measurements were highly correlated (r² > 0.99, P < 0.001).     

Length‐weight relationships of three cyprinid fishes from Sirwan River,Kurdistan and Kermanshah provinces in western Iran

The length–weight relationships (LWR) for three fish species collected in Sirwan River, located in Kurdistan and Kermanshah provinces, western Iran, were estimated. The values of the slope parameter (b) in the length–weight relationship equations were determined as 3.086 for Alburnus mossulensis, 3.382 for Alburnus filippii and 3.425 for Capoeta damascina, all significantly different from the expected b = 3 value, indicating a positive allometric growth pattern for all the three species.     

Length–weight and length–length relationships of eight fish species from river Ganga,India

Present study provides length–weight relationships (LWRs) and length–length relationships (LLRs) of eight fish species from river Ganga, India. Specimens were sampled from gill nets (mesh, 22–120 mm), cast nets (mesh, 12–14 mm), and seine nets (mesh, 12 mm) on quarterly basis from September 2016 to September 2017 within the river stretch from Buxar (25°33′43.90″N and 83°56′3.10″E) to Freserganj (21°35′40.58″N and 88°15′28.92″E). The b value ranged from 2.86 (Otolithoides pama) to 3.08 (Polynemus paradiseus), whereas a value ranged from 0.004 (P. paradiseus) to 0.016 (Rita rita). Both relationships (LWRs and LLRs) were found to be highly correlated (p < .001). This study provides first report on LWR for Amblyceps mangois and Osteobrama cotio, whereas new maximum length recorded for Macrognathus pancalus. Furthermore, the estimate of R. rita should be considered as tentative because of the limited size range in the study.     

Length–weight and length–length relationships of eight fish species from Bohai Bay,China

Length–weight and length–length relationships (LWRs and LLRs) for eight fish species collected quarterly by trawl net in Bohai Bay, China, were estimated in a total of 1,395 specimens from 2012 to 2015. These were Pholis fangi, Setipinna taty, Engraulis japonicus, Larimichthys polyactis, Thryssa kammalensis, Scomberomorus niphonius, Johnius grypotus and Sardinella zunasi. The LWRs for the last two fish species are first reports for FishBase.     

Length–weight and length–length relationships for 135 fish species from the Xingu River (Amazon Basin,Brazil)

Length–weight (LWR) and length–length relationships (LLR) are presented for 135 freshwater fish species sampled by several types of fishing gear between April 2012 and July 2014 in the middle and lower Xingu River Basin, northern Brazil. The report represents the first references on LWRs and LLRs for 114 and 119 species, respectively, and also provides a new maximum size for 96 species.     

Length–weight and length–length relationships for 11 species of the genus Alburnoides Jeitteles, 1861 (Cyprinidae) from Iran

Length–weight (LWR) and length–length (LLR) relationships were estimated for 11 Alburnoides species from 15 localities throughout Iran. These represent the first reports of LWR and LLRs data for 10 species, including: Alburnoides coadi (40 specimens), A. damghani (30), A. eichwaldii (110), A. holciki (30), A. idigensis (113), A. namaki (30), A. nicolausi (30), A. parhami (30), A. qanati (30) and A. tabarestanensis (30) and first LLR data for A. samiii. Nine of these species are endemic and two are native to Iran. The length–weight parameter b for these species ranged from a minimum of 2.94 for Alburnoides nicolausi to a maximum of 3.37 for Alburnoides parhami, with regression coefficients (r²) ranging from 0.91 to 0.99. All LLRs were highly significant (r² > 0.96).     

Length–weight and length–length relationships of 11 fish species from Zhimai River estuary,China

The present work provides the length–weight relationships (LWRs) and total length – standard length relationships (LLRs) of 11 fish species belonging to six families. The fishes were collected from seasonal bottom trawl surveys in the Zhimai River estuary, March 2011 to May 2013. This is the first record of LWRs and LLRs for several of the fish species in this area.     

Length–weight and length–length relationships of fish species from the Chi River,northeastern Thailand

The relationships of total length (TL), fork length (FL) and standard length (SL) are presented for four fish species and the relationships between TL and wet weight for 23 fish species from the Chi River in northeastern Thailand. All length–length relationships were linear (r² > 0.95). Slope (b) of the length–weight relationships showed values between 2.5073 and 3.4896.