Length–weight relationship of nine fish species from Skadar Lake (Adriatic catchment area of Montenegro)

This study provides data on the length–weight relationships (LWR) of nine fish species sampled between 2010 and 2014 from Skadar Lake, Montenegro. Also provided are the first comprehensive data of LWRs for three freshwater fishes for which no LWR information was available in the FishBase data bank. The b parameter values ranged from 2.936 to 3.271, while values of the a parameter ranged from 0.002 to 0.014.     

Length–weight relationships for nine fish species in Lake Dianshan,China

Presented are the relationships between fork length (FL) and weight (W) for nine fish species sampled from 2010 to 2012 in Lake Dianshan, Shanghai, China. Values of the parameters a ranged from 0.005 to 0.017 and b values ranged from 2.590 to 3.511; all r² for the relationships were higher than 0.950. A new maximum length for Plagiognathops microlepis is also reported.     

Length–weight relationships of seven myctophid fishes (Myctophiformes: myctophidae) in the South China Sea

The study included 546 specimens of seven myctophid fish species from the South China Sea (captured during June 2015 by bottom and mid‐water trawls). Length‐weight relationships (LWRs), W = aL^b, were estimated using standard length. The species belong to four genera. The values for the parameter a ranged from 0.006 to 0.022, while the b values ranged from 2.710 to 3.476 (Range of r² values: .938 to .971). According to FishBase, this study presents the first LWRs for these species, including two maximum standard lengths for Diaphus chrysorhynchus and Notoscopelus resplendens.     

The weight‐length relationship of fish species found in the tidal creeks of the Amazon estuary,northern Brazil

The present study estimated the a and b parameters of the weight‐length relationship of five fish species that inhabit the tidal creeks of islands in the Amazon estuary: Colomesus asellus, Geophagus proximus, Lithodoras dorsalis, Pseudauchenipterus nodosus, Pachypops fourcroi. The species were collected quarterly between October 2013 to July 2014 using block nets made from 20 mm mesh size. The b coefficient of the regression of the weight on the total length of these species ranged from 2.71 to 3.14. These are the first reference on the weight‐length relationship for three species and the new maximum length recorded for two species.     

Length–weight relationships of the invasive topmouth gudgeon (Pseudorasbora parva) in ten lakes in the UK

The topmouth gudgeon (Pseudorasbora parva) is a species that is becoming invasive in UK waters. Few biological studies have been completed on the species in this extended range, resulting in sparse information in some aspects of their invasion biology. Regarding length–weight relationships, this is remedied in this study by providing data for 10 lake populations in the UK. Using fish length range 2.5–11.8 cm, values of a and b in the length–weight equation are provided. Values of b ranged between 2.76 and 3.32. Across all lakes, the relationship was W = 0.011L^3.03, with weight in grams and length (fork) in cm.     

Length–weight relationships of 16 fish species from the Tarim River,China

This paper reports the length–weight relationships of 16 fish species belonging to three families and ten genera from the Tarim River in China. Length–weight relationships for ten fish species were unknown to Fishbase, and new maximum lengths are given for six species. The r² values ranged from 0.972 to 0.995. Values of b varied from 2.79 to 3.49.     

A review of length–weight relationships of fishes from freshwaters of Turkey

This paper presents 145 length–weight relationships gathered from the literature pertaining to 30 Turkish freshwater fish species belonging to six families. The value of the slope b ranged from 2.04 for Carassius carassius to 3.46 for Scardinus erythroptalmus. The mean value of b was 2.91 (SD = 0.305), which did not differ significantly from 3.0 (t‐test, P > 0.05). The median value of b was 2.95; 50% of the b values ranged from 2.68 to 3.14. The plot of log a vs b was used to detect outliers.     

Length–weight relationships for six fish species from the middle of the Yalu Tsangpo River,China

This paper reports the length–weight relationships for six fish species belonging to the Cyprinidae from the middle of the Yalu Tsangpo River in China. Samples were obtained by electroshock and drift net fishing techniques (mesh size 2 cm × 3 cm; 200 m net length) in April and September to October 2014. Length–weight relationships estimates for these species were not available in FishBase. A total of 737 specimens were used to estimate the a and b parameters. New maximum total lengths are also reported for six species. The r² values range from 0.98 to 0.99. Values of b vary from 2.88 to 3.19.     

Weight–length relationships of 36 fish species from the River Strymon system (northern Greece)

We present 54 weight–length relationships pertaining to 36 fish species, caught in the Greek part of the River Strymon system (northern Greece). The total weight (W) – total length (TL) relationships were estimated using the logarithmic form of the equation W = aTL^b. The exponent b ranged between 2.34 and 3.95, (mean ± SE: 3.16 ± 0.044). For 5 out of the 36 species weight–length parameters are presented for the first time.     

Length–weight relationship of six notothenioid species from sub‐Antarctic waters (Beagle Channel,Argentina)

This study presents length‐weight relationships (LWR) for six species of fishes of the Suborder Notothenioidei that inhabit the sub‐Antarctic waters of the Beagle Channel (Argentina). These species represent five of the nine families of this Suborder. The specimens belong to historical fish collections in the area (from 1987 to 1990) using gill and trammel nets. All species but Eleginops maclovinus had no previous LWR estimates. The coefficient of determination (r²) ranged from 0.91 to 0.99 and b values ranged from 2.74 to 3.2. Harpagifer bispinis was the only species with a b value lower than three. This information is useful to predict the weight from the length data and to provide insights into the ecology of sub‐Antarctic nototheniod fish.     

Cube law, condition factor and weight–length relationships: history, meta-analysis and recommendations

This study presents a historical review, a meta‐analysis, and recommendations for users about weight–length relationships, condition factors and relative weight equations. The historical review traces the developments of the respective concepts. The meta‐analysis explores 3929 weight–length relationships of the type W = aL^b for 1773 species of fishes. It shows that 82% of the variance in a plot of log a over b can be explained by allometric versus isometric growth patterns and by different body shapes of the respective species. Across species median b = 3.03 is significantly larger than 3.0, thus indicating a tendency towards slightly positive‐allometric growth (increase in relative body thickness or plumpness) in most fishes. The expected range of 2.5 < b < 3.5 is confirmed. Mean estimates of b outside this range are often based on only one or two weight–length relationships per species. However, true cases of strong allometric growth do exist and three examples are given. Within species, a plot of log a vs b can be used to detect outliers in weight–length relationships. An equation to calculate mean condition factors from weight–length relationships is given as K_mean = 100aL^b?3. Relative weight W_rm = 100W/(a_mL^bm) can be used for comparing the condition of individuals across populations, where a_m is the geometric mean of a and b_m is the mean of b across all available weight–length relationships for a given species. Twelve recommendations for proper use and presentation of weight–length relationships, condition factors and relative weight are given.     

Length–weight and length–length relationships of 26 fish species from the Yiluo River,a tributary of the Yellow River,China

From February to October 2016, a total of 9,754 fish specimens were collected from the Yiluo River, a tributary of the Yellow River, China's second longest river. Based on these samples, length–weight relationships (LWRs) and length–length relationships (LLRs) were estimated for 26 species. Among these data, LWRs for 1 species, LLRs for 11 species, and maximum total lengths for six species were not previously recorded in FishBase. The a values of the LWRs varied between 0.0019 and 0.0116, and b values from 2.805 to 3.883. All regressions for LWRs and LLRs were highly significant (p < .001). These results will be useful for sustainable management and conservation of the fish resources in the Yiluo River and the Yellow River ecosystem.     

Length–weight relationships of wild fish captured at the mouth of Río Verde,Oaxaca, México and connected lagoons (Miniyua,El Espejo,Chacahua and Pastoría)

Length–weight relationships (LWR) were estimated for 34 fish species belonging to 25 genera and 17 families, specimens were collected near the mouth of the Río Verde, Oaxaca, Mexico. All r² values are statistically significant (P > 0.0001). The values of ‘b’ ranged from 2.55 and 3.3, within the usual range (2.5–3.5). This study provides the first LWR references for six species, and new maximum length records for eight species.     

Length–weight relationships for five endemic fish species in the upper Yangtze River basin,China

Length – weight relationships were estimated for five endemic fish species in the upper Yangtze River: Platysmacheilus nudiventris Luo, Le & Chen, 1977, Xenophysogobio nudicorpa (Huang & Zhang, 1986), Homatula potanini (Günther, 1896), Leptobotia rubrilabris (Dabry de Thiersant, 1872), and Euchiloglanis kishinouyei Kimura, 1934. The a values ranged from 0.0079 to 0.0134, and b values from 2.833 to 3.081. These five endemic species are rare, small and difficult to find and capture. Thus the sampling period was lengthy, from May 2010 to May 2014. A total of 718 specimens were available for analysis, and the length – weight relationships are the first reports for these five endemic fish species.     

Length–weight relationships of five fish species from the Beijiang River,China

The length–weight relationships (LWRs) were determined for five fish species from the Beijiang River in China. Fishes were caught by gill nets (mesh sizes: 5, 7, 9 cm), and cage nets (mesh sizes: 0.5 cm) from April to September 2018. Length–weight relationships of four species were unknown to FishBase, and new records of maximum lengths are given for two species, one of which, Ancherythroculter lini, is endemic species of the Pearl River. All length–weight relationships were highly significant on a log scale with the coefficient of determination (r²) values ranged from 0.939 to 0.991. Values of b were within the expected range, varied from 2.935 for A. lini to 3.414 for Parasinilabeo assimilis.     

Length–weight relationships of five fish species collected from Manora Channel and associated backwaters of the northern Arabian Sea

This paper provides length–weight relationships estimated for five fish species (four families) economically important not only to the local community, but to the larger Indo‐Pakistan sub‐continent. All fish were collected from the Manora Channel and backwater creeks near Karachi, Pakistan in the northern Arabian Sea during July 2000 to October 2002. These represent the first reports of length–weight data for two species (Sardinella sindensis and Pomadasys stridens) while also providing additional data on the remaining three species (Alepes kleinii, A. melanoptera, and Liza carinata) for which limited information was available. Estimated b values obtained for the six species ranged from a minimum of 2.310 for L. carinata to a maximum of 3.082 for S. sindensis.     

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.     

Length–weight relationships and length at first maturity for nine fish species of floodplain lakes in Central Amazon (Amazon Basin,Brazil)

Length–weight relationships are presented for nine fish species from the floodplain lakes in the Central Amazon (Amazon Basin, Brazil). The parameter slope b values in the length–weight relationships ranged from 2.33 to 3.28 for grouped sexes, and from 2.7 to 3.61 for separated sexes. Differences between sexes were verified in three species. Sizes at first sexual maturation ranged from 9.14 to 23.97. This study provides a new reference for the length–weight relationships of six species.     

Length–weight and length–length relationships of seven freshwater fish species from the Daning River,a tributary of the Yangtze River,southwest China

This study determined the length–weight relationships (LWRs) and length–length relationships (LLRs) of seven freshwater fish from the Daning River, a tributary of the Yangtze River, southwest China. Specimens were collected between July 2016 and July 2017 using drift gill nets (mesh size 1, 2 and 3 cm), cage net (0.5 cm mesh size) and electroshock fishing techniques quaterly. Parameter b values of LWRs ranged from 2.647 to 3.276 (r² > .963) and b values of LLRs ranged from 1.091 to 1.213(r² > .985). Six new LLRs and seven new maximum length data are presented. The biometric data and their relationships are relevant to Fishers science to supplement other data sets needed for fisheries management.     

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.