Length‐weight relationship of 11 fish species from a tributary of the Amazon River system in northern Brazil

The length–weight relationships (LWRs) of 11 freshwater fish for eight families (Leporinus friderici, Pterophyllum scalare, Geophagus camopiensis, Curimata incompta, Astyanax bimaculatus, Tetragonopterus chalceus, Moenkhausia lepidura, Metynnis lippincottianus, Plagioscion squamosissimus, Hemiodus unimaculatus and Colomesus asellus) captured in tributary of the Amazon River system (Brazil) were investigated. These results represent the first reference on the LWRs for all 11 species in the eastern Amazon.     

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 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.     

The length-weight relationship of four fish species captured in the Ibicuí River,southern Brazil

Length-Weight relationship (LWRs) were estimated for four fish species occurring in the Ibicuí River drainage basin, southern Brazil. Samples were captured monthly during the spring and summer seasons (October 2018 to March 2019). The fish were caught with gillnets of different meshes (15, 20, 25, 30, 40 mm between adjacent nodes) and a trawl net (5 mm mesh between adjacent nodes) Eighteen excursions were realized in three sites, with a length of approximately 100 km, in third-order flux, all distributed in sub-basin Ibicuí River. The captured tools were installed at the end of the day (6 p.m.) and removed around 6 a.m. the next day. The present study provides the length-weight relationship for four species (Astyanax dissensos, Galeocharax humeralis, Hypostomus roseopunctatus e Hypostomus uruguayensis).     

Length–weight relationships of five fish species from the Nujiang River (Salween basin), southwest China

This study provides the total length–weight relationships (LWRs) for five fish species collected from the Nujiang River, southwest China. Samples were obtained in May 2015 and May 2016 using drift net and electroshock fishing techniques. A total of 502 specimens belonging to five fish species were analyzed; their LWRs were calculated. The five fish were Schizothorax nukiangensis, Akrokolioplax bicornis, Creteuchiloglanis kamengensis, Channa gachua and Glyptothorax trilineatus. Prior to this study, the length‐weight relationship for S. nukiangensis is unknown to FishBase and new maximum lengths are recorded for A. bicornis and C. kamengensis.These results are useful for fishery research, conservation and management in the Nujiang River.     

Length‐weight relationships of five fishes from the middle Heilongjiang River,China

Length–weight relationships (LWRs) were estimated for five fish species in the Fuyuan reach of the middle reaches of Heilongjiang River, northeast China. Fishes were captured using a variety of nets (i.e. drift gill net, set net, fishing cage, fishing jig and fishhook). In addition to November–April, samples were collected monthly from May 2013 to October 2014. The five species were: Lethenteron reissneri, Pelteobagrus ussuriensis, Hemibarbus maculates, Xenocypris macrolepis and Chanodichthys erythropterus. LWRs for Lethenteron reissneri and Pelteobagrus ussuriensis were unknown to FishBase. The a values obtained ranged from 0.0019 (Lethenteron reissneri) to 0.0177 (Pelteobagrus ussuriensis), and b values ranged from 2.710 (Pelteobagrus ussuriensis) to 3.397 (Chanodichthys erythropterus).     

Length–weight relationships of seven fish species from a fish landing port at Sungai Udang,Penang, Malaysia

The length–weight relationships (LWRs) are described for seven fish species from four families (Ariidae, Clupeidae, Leiognathidae and Sciaenidae) inhabiting Penang waters. A total of 471 specimens were sampled and measured from 19 to 20 January 2015, using a bottom trawl net with a 38 mm mesh size of cod‐end. No information regarding LWRs was reported previously in FishBase for Cryptarius truncatus, Escualosa thoracata, Johnius carouna, Nuchequula blochii, Plicofollis argyropleuron, Secutor hanedai or Secutor megalolepis, and the study also provides a new FishBase record of maximum total length for Escualosa thoracata (10.6 cm), Secutor hanedai (9.1 cm) and Secutor megalolepis (7.5 cm).     

Length–weight relationships of five Gobiidae species from Bohai Bay,China

Length–weight relationships (LWR) for five Gobiidae species collected by trawl net in Bohai Bay, China, were determined. Parameter b in the LWR was 2.871, 2.664, 2.901, 3.237 and 2.882 for Amblychaeturichthys hexanema, Synechogobius ommaturus, Odontamblyopus rubicundus, Tridentiger barbatus and Paratrypauchen microcephalus, respectively. This is the first report in FishBase for the fitted LWRs of three of the Gobiidae species mentioned above.     

Length–weight relationships of five fish species from an Atlantic coastal drainage in Brazil

Length–weight relationships (LWR) are presented for five fish species from the Restinga de Maricá, southeastern Brazil. Specimens were caught in pools and streams with different types of fishing gear: seine net, dip net, and sieve. The LWRs of three species are new for this region, and of Phalloptychus januarius are published for the first time.     

Length–weight relationships of four cavefish species from China

Length‐weight relationships (LWRs) were estimated for four cavefish species belonging to the genus Sinocyclocheilus (Cypriniformes: Cyprinidae) occurring in the Nanpanjiang River and Hongshuihe River, which constitute the upstream of the species, S. angularis, S. furcodorsalis, S. rhinocerous, and S. tileihornes, were collected from 2011 to 2017. The b values of LWRs of these four species ranged from 2.830 to 3.719 and the correlation coefficient values (R²) were high for all species. This is the first record of LWRs for cavefish species with the horn in FishBase database.     

Length–weight relationships of seven freshwater fishes from the JiangSu province,China

The length‐weight relationships (LWRs) are presented for seven freshwater fish species (Odontobutis potamophila, Protosalanx chinensis, Acheilognathus chankaensis, Megalobrama skolkovii, Pelteobagrus vachelli, Macropodus chinensis, Pseudobrama simoni) from JiangSu province in China. A total of 1340 specimens were sampled and measured between August 2012 and September 2013. No information regarding the LWRs of these species was available in FishBase.     

Length‐weight and length‐length relationships of three small indigenous fishes from the Payra River,southern Bangladesh

Length‐weight relationships (LWRs) and length‐length relationships (LLRs) for three small indigenous fishes (Esomus danrica, Pachypterus atherinoides and Salmostoma bacaila) were reported from the Payra River, southern Bangladesh. Samples were collected using traditional fishing gear including cast net (mesh size ranges from 1.0 to 2.0 cm), seine net (mesh size ranges from 1.5 to 2.5 cm) and square lift net (mesh size ~ 1.0 cm) in August to September 2017. Allometric coefficient (b) values were 2.66 for E. danrica, 3.08 for P. atherinoides and 3.06 for S. bacaila. The LLRs were also highly significant with r² ≥ .956.     

Length–weight relationships for 10 elasmobranch species from the Oman Sea

Length–weight relationships (LWRs) were estimated for ten elasmobranch species from Iranian waters of the Oman Sea. All specimens were collected by bottom trawl (mesh size 80 mm in the cod end) between May and December 2014. A total of 509 individuals (107 Torpedo sinuspersici, 68 Rhinobatos punctifer, 63 Chaenogaleus macrostoma, 72 Himantura walga, 80 Himantura gerrardi, 58 Gymnura poecilura, 4 Himantura uarnak, 4 Rhinoptera javanica, 14 Aetobatus flagellum, and 39 Pastinachus sephen) were sampled and studied. Results showed that most species had positive allometric or isometric growth but that more studies were needed for final decisions on growth patterns. Both the disk length‐body weight (DL/BW) and disk width‐body weight (DW/BW) relationships also showed a good fit, reinforcing the credibility of the data in relation to the LWRs. This study is the first report of LWRs for these elasmobranchs in the northern Oman Sea.     

Length-weight relationships of seven cyprinid fish species from the Kaptai Lake,Bangladesh

Length-weight relationships (LWRs) were estimated for seven small indigenous cyprinid fish species including Securicula gora, Osteobrama cotio, Esomus lineatus, Pethia gelius, Megarasbora elonga, Gonialosa manmina and Glossogobius aureus occurring in the Kaptai Lake, Bangladesh. Fish were collected monthly basis between March and October, 2018 from fishermen catches landed in the fish landing center, Rangamati. Fishermen operated lift net (mesh size < 0.5 cm), punti net (mesh size < 0.5 cm) and cast net (mesh size < 0.5 cm) for capturing these species. The value of exponent b ranged between 2.769 and 3.212 and regression parameter r² was between 0.926 and 0.992. New maximum total lengths were recorded for E. lineatus and G. manmina in this study.     

Length–weight relationships of nine freshwater fishes from six rivers of the Western Ghats of India

Length–weight relationships (LWRs) were estimated for nine freshwater fish species collected three times using a scoop net (mesh size 0.3–0.5 cm), cast net (mesh size 1–1.5 cm) and gillnet (mesh size 2.5–4.5 cm) from six rivers of the Western Ghats of India during August 2017–October 2018. The b values for LWRs varied from 2.862 to 3.656 (R² > 0.916 and p < 0.0001 for all species).     

Length–weight relationships of ten fish species from the Jingjiang reach of the Yangtze River,China

The length–weight relationships (LWRs) were estimated for ten fish species from the Jingjiang reach of the Yangtze River, China. Samples were collected using a combination set-net consisting of a 40-meter net wall (mesh size: 1.8 cm) and two fyke nets (mesh size: 0.9 cm) on the 1st, 11th and 21st of each month from January 2012 to December 2017. The b values of all species were within the expected ranges, varying between 2.849 and 3.292. This study provides the LWR parameters for Distoechodon tumirostris, Microphysogobio microstomus, Saurogobio dumerili, Squalidus nitens, Acheilognathus gracilis, Sarcocheilichthys kiangsiensis, Sarcocheilichthys parvus, Rhodeus fangi, Micropercops swinhonis, Repomucenus olidus.     

Length‐weight relationships of insular cichlids from Patos Lagoon estuary,subtropical Brazil

The present study reports the length‐weight relationships (LWRs) of three cichlids (Crenicichla lepidota, Cichlasoma portalegrense and Geophagus brasiliensis) collected in a system of pools of the largest estuarine island of Patos lagoon, southern Brazil. Fishes were sampled during random field trips performed from April 2015 to April 2016, using a beach seine (net 5 × 2 m; mesh size 5 mm) and a hand net (diameter 45 cm, mesh size 2 mm). The LWRs for C. portalegrense are presented herein for the first time.     

Length–weight relationships of nine rarely occurring carangids in the northern Arabian Sea coast of Pakistan

In this paper, we document length–weight relationships (LWRs) for nine rarely occurring carangids, opportunistically sampled form commercial catches between 2012 and 2015 being fished from the northern Arabian Sea coast of Pakistan. After confirmation in the FishBase database all nine species Alectis indica (25), Alepes melanoptera (20), Alepes vari (22), Atropus Atropos (25), Carangoides praeustus (50), Seriolina nigrofasciata (21), Trachinotus blochi (30), Trachinotus mokalee (34) and Uraspis uraspis (17) found no LWRs previously documented. The slope values for species presented range from 2.44 to 2.93, intercepts 0.0001–0.048, coefficient of determination 0.89–0.99, and confidence intervals for slopes and intercepts of each species calculated. The LWRs data of nine species would be added in the FishBase database, and provide underlying biological data to the regional biologist for further exploration of these species.     

Length–weight and length–length relationships of three ecologically important fishes caught from a wetland,northeastern Bangladesh

Length–weight relationships (LWRs) and length–length relationships (LLRs) of three ecologically important fishes (Aplocheilus panchax, Danio rerio and Esomus danrica) were reported from a wetland, northeastern Bangladesh (23 58 N, 89 38 E). Samples were collected monthly using traditional fishing gear including fine meshed (2.0 mm) push net and fine meshed (3.0–4.0 mm) surrounding net during January to December 2014. For each individual, total length (TL), fork length (FL) and standard length (SL) was measured to 0.1 cm, while body weight (BW) was measured to 0.01 g accuracy. Allometric coefficient (b) values were 3.10 for A. panchax, 3.38 for D. rerio and 3.52 for E. danrica. In addition, the LLRs were also highly significant with r² ≥ 0.954.     

Length‐weight relationships of Acanthopagrus longispinnis (Valenciennes, 1830), Raconda russeliana (Gray, 1831) and Coilia neglecta (Whitehead, 1967) from the Bay of Bengal coast,Bangladesh

Current study reports the length‐weight relationships (LWRs) of three marine fish species collected from the fishermen catches covering three seasons i.e., rainy, autumn and winter between June, 2016 and February, 2017. Fishermen caught the species using beach seine net (3.5 cm mesh size) and set bag net (0.5 cm mesh size) up to 200 m far away from the shoreline. The LWRs for fish species were W = 0.0180TL^3.192 for A. longispinnis, W = 0.0109TL^2.971 for R. russeliana and W = 0.0098TL^2.942 for C. neglecta with their r² values of 0.971, 0.962 and 0.997, respectively.