Length–weight and length–length relationships for nine species of the genus Paracobitis (Nemacheiliidae) in Iran

Length–weight (LWR) and length–length (LLR) relationships were estimated for 330 specimens from nine Paracobitis species in 11 localities throughout Iran. All fish were collected upon occasion by electrofishing throughout Iran from July 2010 to October 2016. These represent the first reports of LWR data for eight species including: Paracobitis atrakensis, P. hircanica, P. longicauda, P. molavii, P. persa, P. rhadinaeus, P. smithi and P. vignai and first LLR data for all species. A new maximum length is reported for P. malapterura. Four of these species are endemic and five species are native to Iran. The length–weight parameter b ranged from a minimum of 2.74 for P. atrakensis to a maximum of 3.01 for P. longicauda, with regression coefficients (r²) ranging from 0.96 to 0.99. All LLRs were highly significant (r² > .96).     

Length–weight and length–length relationships of two goby species,Neogobius caspius (Eichwald, 1831) and Proterorhinus nasalis (De Filippi, 1863) from the southern Caspian Sea

The present study provides the length–weight (LW) and length–length (LL) relationships for two goby species, Neogobius caspius and Proterorhinus nasalis, which were captured in the southern Caspian Sea. Total length (TL) and standard length (SL) were determined as well as weight. Specimens were collected monthly from September 2014 to August 2015 by beach seine (mesh size 10 mm). The LW parameter b for these species was 3.17 and 2.99, respectively, with a high coefficient of determination (r² > .95). All LLRs were highly correlated (r² > .97). Both species had no previous LWR and LLR estimates in FishBase.     

Length‐weight and length‐length relationships of the genus Alosa (Clupeoidei: Clupeiformes: Clupeidae) along the southern Caspian Sea coast

Length–weight (LWR) and length–length (LLR) relationships were estimated for four shad species of the genus Alosa, reported from along the southern Caspian Sea coast, north of Iran in a study from March 2014. Two of these species are endemic to the Caspian Sea. The length–weight parameter b for these species ranged from 2.99 to 3.24, 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 for two gobiids from the Anzali Wetland,in the southern Caspian Sea basin

Length–weight (LWR) and length–length (LLR) relationships were estimated for specimens of two gobiid species collected from the Anzali Wetland and its related streams in the southern Caspian Sea basin, in August 2017. These represent the first reports of LWR and LLR data for Rhinogobius cf. similis Gill, 1859 (37°28′13″N, 49°20′33″E; 50 individuals) and Proterorhinus nasalis (De Filippi, 1863) (36°54′10.89″N, 53°48′48.33″E; 30 individuals) from the Wetland. A new maximum length is reported for P. nasalis. The length–weight parameter b for these species ranged a minimum of 2.99 for Rhinogobius cf. similis to a maximum of 3.04 for P. nasalis with regression coefficients (r²) ranging from .95 to .97. All LLRs were highly significant (r²>.96).     

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,length–length relationships and feeding habits of wild Indus Mahseer,Tor macrolepis,from Attock,Pakistan

In this study the length–weight (LWR) and length–length relationships (LLR) were carried out for Indus Mahseer, Tor macrolepis, from the Haro River and Nalah Kala, Attock, Pakistan. A total of 118 specimens were used to estimate the relationship parameters. The results of LWR (W = a TL^b) from five different sites indicated W = 0.0044 TL^3.14, W = 0.0054 TL^3.08, W = 0.0059 TL^3.21, W = 0.0076 TL^3.12, and W = 0.0107 TL^2.99, respectively, with an overall value of W = 0.0100 TL^2.94. All regressions for LLR were highly significant (P ≤ 0.001), with coefficient of determination (r²) values of > 0.90. All relationships for LWR and LLR were found to be isometric. T. macrolepis is principally a herbivorous bottom feeder, mainly feeding on aquatic plants and algae, supplemented by insects.     

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 of four species of genus Pethia and genus Puntius from wetlands of Lakhimpur district,Assam, India

Length–weight relationships (LWR) and length–length relationships (LLR) were estimated for four species, namely, Puntius sophore (Hamilton, 1822), Puntius chola (Hamilton, 1822), Pethia ornatus (Vishwanath & Laisram, 2004) and Pethia ticto (Hamilton, 1822) collected from different wetlands of Lakhimpur, Assam. The values of the parameter slope (b) in the LWR were 3.30 for Puntius sophore, 3.22 for Puntius chola, 2.61 for Pethia ornatus and 3.27 for Pethia ticto. The relationships among TL, FL and SL were all linear (r² > 0.95).     

Length‐weight relationships of four fish species from the continental shelf of Yucatán (SW Gulf of México)

This paper presents length‐weight relationships (LWR) for four fish species from the continental shelf of Yucatán, at the Sonda de Campeche (southwestern Gulf of México). Samples were taken using shrimp trawl nets (5.71 cm squared mesh size in the cod‐end) in the mid‐summer of 2016. All LWRs were significant with r² values ranged from .946 to .994 and the values of exponent b, estimated using simple linear least squares of log‐transformed weight and length data, ranged from 2.54 to 3.10 (p < .001).     

Length–weight and length–length relationships of four fish species from the middle reaches of the Minjiang River,southwest China

Length–weight (LWR) and length–length (LLR) relationships are reported for Glyptothorax fokiensis (Rendahl, 1925), Microphysogobio kachekensis (Oshima, 1926), Pseudobagrus brevicaudatus (Wu, 1930), and Sinibrama taeniatus (Nichols, 1941) from the middle reaches of the Minjiang River and its tributaries, Sichuan Province, in southwest China. A total of 675 specimens were obtained between 2013 and 2016 using various types of fishing gear and electroshock fishing techniques. Standard length and total length for each individual were measured by digital slide caliper and each body weight was taken by digital balance. The b‐values for LWRs varied from 2.617 to 3.249 (r² > .954), and the LLRs were highly correlated (r² > .983; p < .01).     

Length–weight and Length‐length relations of four fish species from the Chilika Lake,East coast of India

This study reports the length–weight relationship (LWR) and length‐length relationship (LLR) estimated for four fish species inhabiting in Chilika Lake, India. Total 504 specimens were sampled from mono‐filament gill nets (mesh size 12 mm, 22–24 mm, 34–38 mm, 42 mm) during January 2015 to December 2015. The estimated b values from LWR ranged between 2.79 (T. biaculeatus) to 3.29 (C. praeustus). In all species, the relationships between length‐weight and length‐length were highly correlated (p < .05). The study provides first world reports on LWRs and LLRs for all the 4 studied species.     

Length–weight relationships of 20 fish species from Bahía de Matanchen,in the southeast Gulf of California,Mexico

Length–weight relationship (LWR) parameters were determined for 20 fish species belonging to 14 genera and seven families. The fishes were collected monthly (May 2013 to February 2014) by soft‐bottom trawls in Bahía de Matanchén, southeast of the Gulf of California. Sizes ranged between 5.5 and 36.0 cm total length (TL) and weighed between 1 and 901 g. The allometric coefficient (b) of the LWR varied from 2.638 for Chloroscombrus orqueta to 3.668 for Neopisthopterus tropicus. This is the first report of LWR estimations for 15 of the species.     

Length–weight and length–length relationships and length at first maturity for freshwater fish species of the Salto Santiago Reservoir,Iguaçu River Basin,Brazil

Length‐weight (LWR) and length‐length (LLR) relationships were estimated for 20 species and lengths at first maturity (L₅₀) for six species of freshwater fishes caught in the Salto Santiago Reservoir, Iguaçu River Basin, Brazil. In nine species significant differences were found in the LWR between sexes. Average b‐value for species with no differences between sexes in LWR was 3.12 (SE = ±0.05). Average b‐value in LLR was 0.823. First references on LWRs and L₅₀ are presented for 13 and four fish species, respectively, as well as the new maximum total lengths for eight species.     

Length–weight and length–length relationships for seven fish species from the Zohreh River,Iran

Length–weight and length–length parameters were calculated for seven fish species belonging to five families in the Zohreh River, Iran. The weight–length relationships were estimated using the equation W = aL^b. The b values varied between 2.72 and 3.33, with a mean ± SD of 2.88 ± 0.28. The b values parameter in the length–weight relationship equations were calculated as 3.15 for Alburnus mossulensis Heckel, 1843; 3.78 for Barilius mesopotamicus Berg, 1932; 2.86 for Cyprinion macrostomum Heckel, 1843; 2.89 for Nuchequula gerreoides (Bleeker, 1851); 2.80 for Mastacembelus mastacembelus (Banks & Solander, 1794); 2.72 for Liza abu (Heckel, 1843); and 3.19 for Paraschistura nielseni (Nalbant and Bianco, 1998). This study presents the first LWR and LLR references for these species in the Zohreh River.     

Length–weight and length–length relationships of three endemic fish species from the Yarlung Tsangpo River,China

The length‐weight (LWR) and length‐length relationships (LLR) were estimated for three endemic fish species, including Schizothorax waltoni Regan, 1905, Schizothorax oconnori Lloyd, 1908, and Schizothorax macropogon Regan, 1905 in the Yarlung Tsangpo River. A total of 399 specimens were collected using gillnets and cast nets during February to August 2012 and March to May 2013. No information regarding length–weight and length–length relationships was reported previously in FishBase for these three endemic species.     

Length–weight relationship for nine freshwater fish species from Wujiang River in China

Length–weight (LWR) relationships were estimated for nine fish species collected in the Wujiang River located near the city of Chongqing, China. The value of the exponent ‘b’ in the LWR was between 2.594 and 3.528, which shows that the species exhibit an allometric growth pattern. All relationships between total length (TL) and body weight (BW) were linear (in all cases: r² > 0.913).     

Length–weight and length–length relationships of four native fish species of the Qinghai‐Tibet Plateau,China

This study presents the length–weight (LWR) and length–length relationships (LLR) of four fish species (Gymnocypris namensis Wu & Ren, 1982; Herzensteinia microcephalus Herzenstein, 1891; Triplophysa stenura Herzenstein, 1888; and Triplophysa brevicauda Herzenstein, 1888) collected from the Qinghai‐Tibet Plateau, China. A total of 291 specimens was collected using electric fishing (12V), gill nets (mesh size: 2 × 2 cm, 3 × 3 cm) and cast nets (mesh size: 2 × 2 cm), in July 1998 and October 2014.     

Length–weight and length–length relationships for nine fish species from Lhasa River Basin,Tibet, China

The present study reports length–weight relationships (LWR) and length–length relationships (LLR) for five native freshwater fish species (Schizopygopsis younghusbandi, Triplophysa orientalis, T. tibetana, T. stewartii and T. stenura) and four introduced freshwater fish species (Pseudorasbora parva, Carassius auratus, Micropercops cinctus and Oryzias latipes) captured in the Lhasa River Basin, Tibet, China. Five of the LWRs are presented for the first time.     

Length–weight relationships of nine fish species from the streams of Hunan Zhangjiajie Chinese Giant Salamander National Natural Reserve,China

Length–weight relationships (LWR), W = aL^b, were estimated for nine fish species belonging to three orders, four families and nine genera from the Hunan Zhangjiajie Chinese Giant Salamander National Natural Reserve, in the northwestern part of Hunan Province of central China. Six of the species are endemic to China, of which three are also endemic to the Yangtze River. The r² value ranged from 0.9546 to 0.9924. Values of b varied from 2.9177 to 3.6752. This study represents the first reference on LWR for nine species, and are new maximum length records for six species.     

Length–length and length–weight relationships of oilfish (Ruvettus pretiosus), escolar (Lepidocybium flavobrunneum), snake mackerel (Gempylus serpens), and longnose lancetfish (Alepisaurus ferox) from the Gulf of Mexico and the western North Atlantic Ocean

Oilfish, escolar, snake mackerel (order Aulopiformes, family Gempylidae), and longnose lancetfish (order Perciformes, family Alepisauridae) sampled from the western North Atlantic and the Gulf of Mexico were analyzed for length–weight and length–length relationships. These species are encountered as occasional bycatch of pelagic longline fisheries. The fish (161 specimens, 19.0–149.1 cm TL) were collected over a 3‐year period (January 2007–January 2010) from pelagic longline gear targeting swordfish and tuna. For each species, 95% confidence limits (CI) of parameters b and log a and regression coefficients (r²) were calculated for log‐transformed length–weight relationships. The length–weight parameter b for all species ranged from 2.881 to 3.358, with regression coefficients (r²) ranging from 0.75 to 0.98. Linear relationships between fork lengths, standard lengths, and total lengths were also calculated.