Length–weight and length–length relationships of three Ambassid fishes from the Ganges River (NW Bangladesh)

Length–weight relationships (LWRs) and length–length relationships (LLRs) are presented for the first time for three Ambassid fish species from the Ganges River, northwestern (NW) Bangladesh. Fish were sampled with traditional fishing gear including cast net (mesh size ranges from 1.0 to 2.0 cm), gill net (mesh size ranges from 1.5 to 2.5 cm), square lift net (mesh size ~ 1.0 cm) and conical and box trap, October 2014 to September 2015. Allometric coefficient (b) values were 3.00 for Chanda nama, 3.10 for Parambassis lala and 3.23 for Parambassis ranga, respectively. Additionally, the LLRs were highly significant with r² ≥ .958. The present observations would be an effective tool for their stock assessment in the Ganges River, NW Bangladesh and surrounding ecosystems.     

Length–weight and length‐length relationships of four endemic fish species caught from Payra River,Southern Bangladesh

The present study estimated the length–weight relationship (LWR) and length‐length relationships (LLR) of four fish species, Ompok pabo (Hamilton, 1822), Acentrogobius cyanomos (Bleeker, 1849), Acentrogobius caninus (Valenciennes, 1837) and Gagata cenia (Hamilton, 1822) collected from the Payra river over a period of 1 year between July 2015–June 2016 using set bag nets and cast nets with a mesh size of 0.5 cm and <0.5 cm, respectively. Altogether 593 individuals of O. pabo (59), A. cyanomos (221), A. caninus (240) and G. cenia (73) were sampled and studied. LWRs of O. pabo, A. cyanomos, and A. caninus are presented for the first time 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 and length–length relationships for six commercial fishes from southern Korean waters

Presented are the relationships between total length and weight, and between total length and standard length for six commercial fishes collected twice a month from local fish markets in southern Korea between 2005–2006 for Acanthopagrus schlegelii (Bleeker, 1854), Hexagrammos agrammus (Temminck & Schlegel, 1843) and Hexagrammos otakii (Jordan & Starks, 1895), and monthly in 2004 for Dentex tumifrons (Temminck & Schlegel, 1843), Doederleinia berycoides (Hilgendorf, 1879) and Scomberomorus niphonius (Cuvier, 1832). The LWR for D. tumifrons is estimated for the first time, and a new maximum length was recorded for S. niphonius. All total length and weight relationships were significant (all r² > .953). The values of exponent b, estimated using simple linear least squares of log‐transformed weight and length data, ranged from 2.945 to 3.317.     

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.     

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 of four small fishes from the Atrai River,Dinajpur, Bangladesh

Length‐weight (LWRs) and length‐length relationships (LLRs) were determined for four fish species collected from the Atari River in Dinajpur of Bangladesh. Sampling took place monthly between January and June 2016, using seine nets of commercial fishermen (mesh size 4 mm). In LWRs (r² > .927, p < .05), slope (b) was estimated as 3.191, 2.992, 3.217 and 3.109 for Acanthocobitis botia, Botia lohachata, Canthophrys gongota and Chanda nama, respectively. In LLRs (r² > .812, p < .05), lengths i.e. TL, SL, HL and FL were highly correlated. The present study on these species would be the baseline for FishBase dataset.     

Length–weight and length–length relationships of five Mystus species from the Ganges and Rupsha rivers,Bangladesh

This study focused on the length–weight and length–length relationships of five Mystus species from Bangladesh. A sum of 398 individuals (Mystus bleekeri = 47, Mystus cavasius = 171, Mystus gulio = 59, Mystus tengra = 65, and Mystus vittatus = 56) was collected from the Ganges and Rupsha rivers, Bangladesh. Fishes were caught by gill net (mesh sizes: 2.0–4.0 cm) and cast net (mesh sizes: 1.5–3.0 cm) from July 2014 to June 2015. Total length (TL), fork length (FL) and standard length (SL) were measured to 0.1 cm, while whole body weight (W) was taken to the nearest 0.1 g for each individual. The TL ranged from 6.0–13.5 cm for M. bleekeri, 5.0–15.0 cm for M. cavasius, 7.4–17.2 cm for M. gulio, 4.6–11.6 cm for M. tengra and 5.5–12.3 cm for M. vittatus. The W varied from 3.0–18.2 g for M. bleekeri, 1.3–30.4 g for M. cavasius, 6.1–62.2 g for M. gulio, 1.7–15.1 g for M. tengra and 2.7–19.2 g for M. vittatus. All LWRs were highly significant (p < .001), with all r² values ≥.950. The LLRs were also highly significant (p < .001), with all r² ≥.980. This study provides information on LWRs and LLRs for M. gulio and M. tengra for the first time. The results of this study can be very effective for stock assessment of Mystus species in the Ganges and Rupsha rivers as well as in the surrounding ecosystems.     

Length–weight and length–length relationships for three endemic Pseudophoxinus species in Turkey

Length–weight and length–length relationships are presented for three endemic Pseudophoxinus species in Turkey. This study provides the first references for these relationships in the species examined.     

Length‐weight and length‐length relationships and form factor of three threatened fishes from the Ganges River (NW Bangladesh)

Data and information are needed to avert the alarming decline and initiate conservation measures for three threatened fishes, Labeo boga (Hamilton, 1822), Nandus nandus (Hamilton, 1822) and Puntius ticto (Hamilton, 1822), from the Ganges River and surrounding ecosystems. These fishes are decreasing rapidly due to high fishing pressures as well as environmental degradation. This study furnishes the length–weight relationships (LWRs), length–length relationships (LLRs) and form factor (a_3.0) of these three threatened species from the Ganges River, northwestern Bangladesh. A total of 773 specimens from the three species and two families used for this study were caught by traditional fishing gear between April 2011 and March 2012. The analysis of covariance (ancova ) revealed significant differences between the sexes in LWRs for L. boga (P < 0.001), but not with the remaining species (P > 0.05). Furthermore, the LLRs were highly correlated (r² > 0.983; P < 0.001), and ancova analyses additionally indicated that LLRs did not differ between sexes (P > 0.05). The calculated form factor (a_3.0) was 0.0111, 0.0159 and 0.0129 for L. boga, N. nandus and P. ticto, respectively. This study presents the first references on LWRs, LLRs and form factor for these three threatened species in Bangladesh. The results would be useful for further studies on the population assessment and sustainable conservation of the limited stocks in the Ganges River ecosystem.     

Length–weight and length–length relationships of three fish species from the Heihe River,northwest China

Length‐weight (LWRs) and length–length (LLRs) relationships are reported for three fish species belonging to two families and two genera from the Heihe River, northwest China. Fish samples were collected using trap nets (mesh size 1 cm) in May and December of 2016, and April and October 2017. Standard length (SL) and total length (TL) for each individual were measured to the nearest 0.1 cm by digital slide caliper and each body weight (BW) was measured to an accuracy of 0.1 g using digital balance. The b‐values for LWRs varied from 2.580 to 3.164 (r² > .956). The results further indicated that the LLRs were highly correlated (r² > .991; p < .01). This study presents the first references on LWRs for Gymnocypris chilianensis and Triplophysa hsutschouensis, and LLRs for G. chilianensis, Triplophysa leptosoma and T. hsutschouensis. This biometric data and their relationships are relevant to the management and conservation of local fishes and fisheries.     

Length–weight and length–length relationships of five fish species in the Atrai River,Dinajpur, Bangladesh

A total of 502 specimens were obtained during monthly samplings from July to December 2015, by fishermen using seine nets, gillnets and cast nets. Length–weight (LWRs) and length–length (LLRs) relationships were estimated for five fish species collected from the Atrai River in the northwestern region of Bangladesh. The values of slope (b) in LWRs (r² > .913, p < .001) were determined as 2.899 for Aspidoparia jaya, 3.059 for Gagata cenia, 3.004 for Gagata youssoufi, 2.755 for Salmophasia bacaila, and 3.222 for Salmophasia phulo, respectively. The linear relationships in TL, FL and SL were highly correlated (for all cases: r² > .897, p < .001). No previous information on LWRs (except for G. cenia) and LLRs (except for S. bacaila) of these selected species were found in FishBase.     

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 and length–length relationships of eight endemic Aphanius species from Turkey

Length–weight and length–length relationships were assessed for eight endemic Aphanius species from Turkey. This study provides a new reference on length–weight and length–length relationships and new maximum sizes for all species examined.     

Length–weight and length–length relationships for three Sillago species (Sillaginidae) from the Persian Gulf

This study investigates length–length and length–weight relationships of three Sillago species [Sillago arabica McKay & McCarthy (Memoirs of the Queensland Museum, 27, 1989, 551), Sillago attenuata McKay, 1985 and Sillago sihama (Forsskål, 1775)] captured in the Persian Gulf, Iran. A collection of 220 specimens was captured from August 2015 to January 2016 by cast net (mesh size: 10 mm) and beach seine (mesh size: 15 mm). The relationships of total length (TL) and standard length (SL) and the relationships between total length and body weight are given. This study presents the first reference on LWRs for two of the species (S. arabica and S. attenuata) in their range of distribution.     

Length–weight and length–length relationships of three Clupeonella species (Clupeidae) from the Caspian Sea

This study investigated length–weight and length–length relationships of three Clupeonella species: C. caspia, C. engrauliformis and C. grimmi captured in the southern Caspian Sea, Iran. Using a lantern net, 206 specimens were collected from July to August 2016. Presented for two of the species are the length–weight and the length–length relationships as well as the first reference on length–weight and length–length relationships for C. caspia in its distribution range.     

Length‐weight and length–length relationships of three algae‐scraping cyprinid species from Iran

The study presents length–weight relationships (LWRs) and length–length relationships (LLRs) for three algae‐scraper species; Capoeta coadi from the Kouhrang River (Iran; 32°23′N, 50°08′E) a part of the Tigris drainage basin, Capoeta pyragyi from Cheshmeh Langan River (32°55′N, 50°10′E) a part of Zayanderud River basin and Capoeta umbla from Chooman River (35°57′N, 45°47′E). Fish were sampled by electro fishing (Samus1000; Power Out: 200 watts) in August, September and October 2017. Sampling was carried out each months in sites covering an area of about 100 m² including runs, riffles and pools at a water depth of 10–60 cm. The obtained LWRs and LLRs showed a high level of correlation (r² > 0.99).     

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.