Length-length Relationships Research Articles

The Hooghly croaker, Panna heterolepis Trewavas, 1977: Identification through morphometric and meristic characteristics

As morphometric information for Hooghly croaker Panna heterolepis Trewavas, 1977 is absent in the most extensively accessed and world’s largest online database for fishes (FishBase); this study was undertaken to provide the complete informative description on morphometric relationships and meristic counts of various fin rays. A total of 200 individuals were sampled from the Bay of Bengal (Bangladesh) during July 2018 to June 2019, using several traditional fishing gears. Meristic counts were computed using a magnifying glass. Body weight (BW) and several length measurements were taken through an electronic balance and digital slide calipers for each individual. LWRs (Length-weight relationships) were calculated as: W = a×L b . All LWRs and LLRs (length-length relationships) were found significant with r 2 ≥ 0.919 ( p < 0.0001) and 0.928 ( p < 0.001), respectively. BW vs. TL and TL vs. SL were the best fitted models for LWRs and LLRs, respectively. Fin formula was: dorsal, D. 43–55 (VIII–X+i/34–44); pectoral, P. 15-17 (i/14–16); pelvic, Pv. 6 (I/5); anal, A. 7–10 (II/5–8); and caudal, C. 17–19 (ii/15–17). These results will a) make a vital contribution for species identification in the marine and coastal waters of Bangladesh and adjoining countries, and b) provide information for Fish Base.

Some population characteristics of Oxynoemacheilus angorae (Steindachner, 1897) from the Perşembe Plateau meandering streams in Ordu, Turkey

Abstract The aim of the current study was to determine the length-weight relationship (LWR) and length-length relationship (LLR) with condition factor (K) values for Oxynoemacheilus angorae from the Perşembe Plateau meandering streams in Ordu, Turkey. A total of 65 fish specimens, which were caught with electrofishing gear, were examined. Fish standard length (SL), fork length (FL), total length (TL), and body weight (W) were determined. There were no statistical differences between the measurements of male and female O. angorae specimens; therefore, the female and male specimens were evaluated together in the current study. The LWR equation and determination coefficient of O. angorae were W = 0.014 TL2.7359 (r2 = 0.9659). The 95% confidence interval of the b value for the O. angorae specimens from the Perşembe Plateau meandering streams was 2.7261 to 2.7435. In the present study, it was determined that O. angorae specimens showed negative allometric growth. Calculations of O. angorae TL-SL, TL-FL, and FL-SL relationship equations and determination coefficients were as follows: TL = 0.2091+1.1646 SL, (r2 = 0.986); TL = 0.1341+1.0301 FL (r2 = 0.9914); and FL = 0.0998+1.1261 SL, (r2 = 0.9868), respectively. A new maximum total length was recorded for O. angorae in this study. The average condition factor value of O. angorae was 0.9954. This value could have indicated that this species was encountering some problems in this habitat. The O. angorae parameters determined were the first data reported for the Perşembe Plateau meandering streams in Ordu, Turkey (Middle Black Sea Region).

Growth, Condition, Maturity and Mortality of the Dwarf Gourami, Trichogaster lalius (Hamilton, 1822) in a Wetland Ecosystem (Beel Dakatia), Southwestern Bangladesh

The dwarf gourami, Trichogaster lalius, is a low-cost freshwater edible fish for the people of South Asian countries containing a variety of essential nutrients. The first wide-ranging explanation on the population parameters specifically; length-frequency distribution (LFD), length-weight relationships (LWRs), length-length relationship (LLR), form factor (a3.0), condition factors (allometric, KA; Fulton’s, KF; relative, KR; relative weight, WR), size at first sexual maturity (Lm) and natural mortality (Mw) of T. lalius were estimated. 768 specimens were collected over one calendar year (March 2019 to February 2020) from a wetland ecosystem named Beel Dakatia, Khulna, southwestern Bangladesh through various traditional fishing gears. Lengths (in cm) and weight (in g) were assessed through a wooden fitted measuring scale and digital balance with accuracy 0.1 cm and 0.01g, respectively. In the current study, the total length ranged from 2.6-9.9 cm while the bodyweight ranged from 0.63-23.80 g for T. lalius. The TL size for classes of 7.00 to 7.99 and 8.00 to 8.99 cm indicated numerically prominent groups. Moreover, the calculated allometric coefficient (b) of LWRs represented a negative allometric growth pattern (b<3.00) for T. lalius in the Beel Dakatia. Noticeably, the a3.0 was 0.015 signifying that the fish is fusiform in shape. KF is the best-suited tool to assess the well-being of T. lalius among the four types of condition factors. According to Wilcoxson signed-rank test, the WR revealed significantly dissimilarities from 100 (P<0.0001), signifying the unbalanced territory for T. lalius. Moreover, the estimated Lm was 5.91 (~6.0) cm TL and Mw was 1.28 year-1 in the Beel Dakatia, southwestern Bangladesh. Finally, the knowledge about the biological aspects of T. lalius may be used for improved management tools in the future.

Length-weight, length-length relationships and condition factor of obtuse barracuda Sphyraena obtusata Cuvier, 1829 (Pisces: Perciformes) from Vizhinjam coast, Kerala, India

Eleven morphometric variables including weight were recorded for 429 specimens of obtuse barracuda Sphyraena obtusata Cuvier, 1829 collected over a period of two years from January 2017 to December 2018, from Vizhinjam fish landing centre, Thiruvananthapuram, Kerala. Length-weight relationship and length-length relationship of the species were estimated using linear regression analysis. Different length measurements were converted to ratios with standard length as morphometric ratios and the growth rate was assessed gender wise. Length-weight relationship for male and female population were estimated as Wm= 13.326 × L3.2409 and Wf = 11.952 × L2.9821, respectively. Linear relationships for other morphometric variables and morphometric ratios with standard length were established for the species. Principal component analysis was performed and total length, snout length and snout to pre-nostril length were identified as key morphometric variables discriminating gender. The relative condition factor was estimated as 1.04+0.13 for total population and the role of morphometric ratios in sex differentiation was examined.

First report of morphometrics and length-length relationships of the common grass yellow butterfly, Eurema hecabe (L.) (Lepidoptera: Pieridae)

The present investigation was conducted to study the morphometrics and length-length relationships (LLRs) of the Common Grass Yellow Butterfly, Eurema hecabe (L.) (Lepidoptera: Pieridiae). Samples were collected randomly from the Rajshahi University Campus (RUC), Bangladesh, and the pictures were taken with a DSLR camera (Canon 750D) and measured using ImageJ software (l.48v). Here, a total of 14 different morphometric lengths viz. total body, antenna, wings (fore- and hindwing) and legs (fore-, mid- and hindleg) were evaluated. Total length (TL) was recorded as a minimum of 11.51 mm and a maximum of 22.01 mm, whereas antenna length (AL) has differed from 5.78-8.68 mm. The highest morphometric mean was found in forewing base-apex (FWBA) as 21.45±2.21 mm, and the lowest mean of length was recorded in the hindleg (HL) as 6.21±0.67 mm. The FWBA was larger than the TL about 33% followed by the forewing base-tornus (FWBT), hindwing base-apex (HWBA), hindwing base tornus (HWBT) and forewing cubitus2 vein (C2V). According to co-efficient of determination (r2) values, the best-fitted model of LLRs was TL vs. foreleg (FL) among 13 equations. The allometric coefficient ‘b’ was suggested positive allometric growth. These works will be very useful for species recognition and taxonomic study of butterflies in the RUC as well as in Bangladesh.

Estimation of morphometric relationships for flathead sillago, Sillaginopsis panijus (Hamilton, 1822) in the Bay of Bengal (Bangladesh) using multi-linear dimensions

This study on flathead sillago, Sillaginopsis panijus (Hamilton 1822) estimates the first morphometric relationships from the marine ecosystem, Bay of Bengal, Bangladesh using multi-linear dimensions. Additionally, meristic counts for different fin-rays were done. Alltogether, 204 specimens were captured during July 2018 to June 2019 by several gears including seine net and long lines. Morphometric measurements as well as body weight (BW) were recorded for each individual. The LWRs (length-weight relationships) were assessed as: W = a × L b . Lateral line scales and fin rays were observed by magnifying glass. The LWRs and LLRs (length-length relationships) were found significant ( p &lt; 0.0001), with the r 2 values being ≥ 0.913 and ≥ 0.952, respectively. Based on r 2 values, LWRs by BW vs. SL and for LLRs, TL vs. FL were found as the best model. Fin formula observed for S. panijus is D 1 IX; D 2 I/24-28; P . 17-20; P v. 1/5; A I-II/24-27; C 2/16-18. Scales on lateral line were ~82-86. This investigation should be helpful for resource management in the marine ecosystems of Bangladesh and other subtropical countries.

Length-weight and length-length relationships of three endemic freshwater fish species from Anatolia, Turkey

This study aims to investigate the length-weight (LWRs) and length-length relationships (LLRs) of three endemic freshwater fish species (Squalius recurvirostris, Squalius carinus and Capoeta turani) living in Turkey. Fish samples were captured with backpack electro-shocker from June 2006 to October 2010. The calculated values of parameter b in the LWRs were 3.363 and 3.045 for S. recurvirostris (Eber and Ilgın Lake populations, respectively), 3.275 for S. carinus and 3.111 for C. turani. The coefficients of correlation (r) for all the LLR equations were greater than 0.95. The growth parameters of S. recurvirostris is provided for the first time in this study.

Length-Weight, Length-Length Relationships and Condition of the Conchfish Astrapogon stellatus Cope, 1867 (Teleostei: Apogonidae) in the Mesoamerican Reef System, Mexico

Length-weight (LWR), length-length (LLR) relationships and relative condition factor (Kn) were determined for the conchfish Astrapogon stellatus (Cope, 1867) in the Mesoamerican Reef System, Mexico. A total of 26 specimens were collected between 2016 and 2018. The LWR for A. stellatus was W = 0.0159*TL2.972. LLR was highly significant (r2 = 0.989) and the range of Kn was 0.85–1.26. These findings have not been previously reported in the literature, such data is valuable for understanding population dynamics for this a poorly known species that could be within some endangered category.

Interrelationship of linear dimensions as growth corollary of pama croaker Otolithoides pama in the Bay of Bengal

Growth pattern of pama croaker Otolithoides pama population in the Bay of Bengal was determinedas the corollary of relationships between standard length (SL) and total length (TL), the two most prevalentlyused linear dimensions of fin fish species. Monthly pama croaker samples were collected from the industrialfisheries in the Bay of Bengal. The length-length relationship was constructed algebraically in the form ofy=a+bx. Relationships between SL and TL for male, female and unsexed populations were separatelyestablished. Sex ratio between male and female did not deviate from the parity (?2 test; p&gt;0.05). The SL andTL ranges of male were 7.2-22 cm and 9.5-28 cm respectively, and the SL and TL ranges of female were6.8-20 cm and 8.4-25.7 cm respectively. Intercept and slope varied monthly in all length-length relationshipsregardless of gender categories. The generalized SL-TL relationships of male, female and unsexedpopulations were TL=1.214SL+0.761(R=0.989), TL=1.212SL-0.770(R=0.990) and TL=1.203SL+0.904(R=0.987) respectively. The correlation coefficients of both monthly and generalized regression analyses ofall sex types were very high (R?0.852) which explained that the relationships between the two lengthdimensions were strongly correlated. The growth corollary appeared both as isometric and allometric formonthly populations. Allometric growth was apparent in July, August and September in all gender types,while isometric growth was deduced in other months. This study would be useful for future research in orderto make comparisons with the relevant aspects of O. pama population between years and locations in the Bayof Bengal.

Short Communication: Length-weight and length-length relationships of eight fish species from Hara Biosphere Reserve; a mangrove swamp in the Persian Gulf

Length-weight and length-length relationships were estimated for eight species occurring in the Hara Biosphere Reserve in the Persian Gulf. Specimens were collected quarterly by block net and drift gillnet from June 2017 to July 2018. The b-values for length–weight relationships varied from 2.693 to 3.321. The study represents the first published information on LWRs for Hemiramphus archipelagicus (Collette & Parin, 1978), Lagocephalus guentheri (Miranda Ribeiro, 1915), and Triacanthus biaculeatus (Bloch, 1786) and first-time reports for FishBase. These species are ranked as rare in the sense that they have a restricted range.

Length-Weight and Length-Length Relationships of the Levantine Barbel Luciobarbus pectoralis (Heckel, 1843) in Asi River, Turkey

Length-weight and length-length relationships are very important in fish biology. These parameters can provide information on the stock condition and growth studies. In this study, we report the length-weight and length-length relationships for Luciobarbus pectoralis in the Southeastern Anatolia (Hatay, Turkey). A total of 125 (65 female and 60 male) specimens were captured from Asi River (Orontes River) basin using gill nets in September 2015 and March 2016. The total length and weight of both sexes varied from 15.5-38.0 cm and 35.0-855 g. The values of the exponent b of the length-weight relationships (LWRs) were 3.441 for females and 3.443 for males. The length-length relationship (LLRs) between the three-length measurements (TL-FL-SL) were highly correlated (R2&amp;gt;0.99, P&amp;lt;0.001). This study provides the first comprehensive description of LWRs and LLRs of L. pectoralis from the Asi River (Hatay, Turkey) according to their sexes. Besides new maximum length and weight are reported for L. pectoralis.

Coefficient of Algebraic Relationship Between Linear Dimensions as Growth Deduction for Rainbow Sardine Dussumieria Acuta in the Bay of Bengal

The intercept as the coefficient of algebraic relationship between standard length (SL) and total length (TL), the two predominantly used linear dimensions of fin fish species, was referred to growth pattern deduction for rainbow sardine Dussumieriaacuta population in the Bay of Bengal. Monthly rainbow sardine samples were collected from the industrial fishing vessel in the Bay of Bengal over a period of a calendar year. The length-length relationship was formed algebraically as y=a+ bx. Linear relationship between SL and TL for male, female and unsexed populations was constructed separately. Chi-squared test affirmed that sex ratio between male and female did not deviate from the parity (P&gt;0.05). The SL and TL ranges of male were 13.1-16.8and 16.4-20.7 cm respectively, they for female were13.4-17.2 and 16.5-20.9 cm respectively. Slope and intercept showed variation monthly in all length-length relationships regardless of sexes. The generalized SL-TL relationships of male, female and unsexed populations employing pooled data over the study period were TL=1.130SL+1.571 (R=0.908), TL=1.106SL+1.925 (R=0.911), and TL=1.114SL+1.825 (R=0.908) respectively. The correlation coefficients of all monthly and generalized regression analyses of all sex categories were very high (R≥0.786), a fact that explained the associations between two length dimensions were strongly related. Study revealed isometric growth for male in all months, while algometry was apparent for female and unsexed populations in a few months. Present findings of length-length relationship and growth pattern for D. acuta population in the Bay of Bengal would remain useful for future references.&#x0D; Res. Agric., Livest. Fish.7(3): 545-551, December 2020

Ankara Asartepe Baraj Gölü’nde Yaşayan Oxynoemachellus angorae (Steindachner, 1897)’ nın Boy-Ağırlık ilişkileri ve Kondisyon Faktörü

Asartepe Baraj Gölü’nde Mart 2015-Şubat 2016 tarihleri arasında yürütülen bu çalışmada Oxynoemacheilus angorae (Steindachner, 1897)’nın boy-ağırlık ilişkileri (LWR), kondisyon faktörü ve boy-boy ilişkileri araştırılmıştır. Elde edilen örneklerin total boyları 4-7,8 cm, toplam ağırlıkları ise 1-5 g arasında dağılım göstermiştir. Boy-ağırlık ilişkisinin fonksiyonel denklemi W = 0,00171×TL2,651 ve korelasyon değeri r2 = 0,80 olarak hesaplanmıştır. Elde edilen b değeri tüm bireylerde istatistiksel olarak 3’ten farklı çıkmamıştır (t-testi, P&gt;0.05). Kondisyon faktörü değerlerinin 0,54-1,5625 arasında değiştiği belirlenmiştir. Elde edilen veriler son çalışmalarda bildirilen sonuçlarla karşılaştırılmıştır. Yapılan bu çalışma ile Asartepe Baraj Gölü’ndeki O. angorae popülasyonuna ait boy-ağırlık ilişkisi, kondisyon faktörü ve boy-boy ilişkisi ile ilgili ilk temel veriler belirlenerek sunulmuştur. Ayrıca, bu çalışma çeşitli ekolojik faktörlerin etkisiyle tehdit altında bu türün korunması ve balık faunası açısından da önem arz etmektedir.

Length-weight and length-length relations for 21 fish species caught in Izmir Bay

This study exhibits relationships between length-weight and length-length for 21 fish species caught in Izmir Bay. Coefficients a and b for the length-weight relationships (LWRs) and length-length relationships (LLRs) were calculated with W=aLb formulae and as equations of TL=a+bFL and TL=a+bSL respectively. Equations of length-length for converting standard length and fork length into total length and vice versa were proven linear. The involved relationships were significantly interrelated (R2&amp;gt;0.942). Values b in the LWRs varied from 2.21 to 3.96 (mean ± SE: 3.15 ± 0.08). The student’s t-test showed that 87.9% of values b were significantly different from 3.

Population structure of &lt;i&gt;Paralonchurus brasiliensis&lt;/i&gt; (Steindachner, 1875) (Perciformes: Sciaenidae) in the coast of Sergipe, northeastern Brazil

Paralonchurus brasiliensis is one of the most common fish species found in the bycatch of shrimp trawling in Sergipe. We analyzed its population structure through four sampling programs, two using hired shrimp trawlers (2013-2014 and 2017-2018) and two from the commercial shrimp fleet (2015-2016 and 2018-2019). The codend mesh size varied among programs (18, 20, and 21 mm). All specimens of P. brasiliensis were identified and had their standard and total lengths (SL and TL; cm) and their total weight (TW; g) measured. A total of 1509 specimens were collected measuring 4.7-22.9 cm TL and 0.4-114.8 g. About 67% of all specimens were below the length at first maturity (14.7 cm). The length-length and weight-length relationships estimated were TL=1.141+1.176×SL and TW=0.00270×TL3.391, respectively. The recruitment probably occurs in September-October and May. This species appeared to be more abundant at 15 m, and larger individuals were found at 5 m. Although P. brasiliensis is frequently caught in shrimp fisheries, it is not reported in catch statistics. Here, for the first time, we have documented its presence in Aracaju’s market under the categories ‘miunça’ and ‘pescadinha’ (97% adults), with the largest specimens landed and commercialized as ‘pescadinha’ together with other species. Smaller individuals are probably discarded by commercial fishers. The low selectivity of the fishing gear used leads to the capture of many juveniles, which may impact the population dynamics of this species as well as other species found in the same fishing ground.

Growth pattern of the Hooghly Croaker Panna heterolepis Trewavas, 1977 in the Bay of Bengal (Bangladesh) in relation to eco-climatic factors

The present study investigated the length-frequency (LFDs) distributions, length-length (LLRs) relationships and growth pattern based on length-weight (LWRs) relationships related to eco-climatic factors of Panna heterolepis captured from the Bay of Bengal, Bangladesh. In total, 1223 specimens (male = 654, female = 569) were collected from January to December 2019. Total length (TL), as well as body weight (BW), was measured by measuring board and digital balance with 0.01 cm and 0.01 g accuracy, respectively. TL varied between 10.70-31.40 cm for males and 10.50-34.50 cm for females. The overall allometric co-efficient (b) value for both sexes indicated negative allometric growth (< 3.00) for most of the months. In addition, the LLR (TL vs. SL) were extremely correlated (p < 0.001), with all r2 ≥ 0.982. The b of LWR was found significantly related to temperature for both sexes. However, rainfall, DO and pH did not reveal any significant correlation with the growth pattern for both sexes. This study recorded the maximum size of females as 34.5 cm TL. The outcomes of the study will be helpful for stock assessment as well as management of this fish in the Bay of Bengal, considering their response to climatic change.

Some reproductive and biometric features of the endangered Gangetic Leaf Fish, Nandus nandus (Hamilton, 1822): Implication to the baor fisheries management in Bangladesh

This study reflects the biometric characters of the endangered species Nandus nandus (Hamilton, 1822) including sex ratio, length-length relationships (LLRs), and length-weight relationships (LWRs) utilizing the sum of 14 linear variables, various meristic measurements, reproductive biology, and condition factor from the Borni Baor, a large wetland ecosystem of southwestern Bangladesh. A total of 579 specimens of N. nandus have been periodically collected from the Borni Baor throughout the year (January–December, 2019) using different traditional fishing gears. Highly significant LLRs (r2 > 0.90) values indicate that length parameters are profoundly associated with one another. In the LWR formula (W = aLb), higher exponent b values (b > 3.0) were demonstrating a positive allometric growth with a high correlation coefficient (r2 > 0.94). Moreover, monthly gonadosomatic index and dobriyal index fluctuations suggest the primary breeding season of this fish is from March to July. Data revealed the breeding time was associated strongly with the rainfall and air temperature (p < 0.05). The results of our study exposed a cutting-edge biometric feature of this endangered species that would be applicable for fish stock evaluation and making management strategies and conservation policy for this valuable fish resource.

Biometry, length-weight and length-length relationships of flathead sillago Sillaginopsis panijus (Hamilton, 1822) (Perciformes: Sillaginidae) from the north-western Bay of Bengal

Biometry, length-weight relationships (LWRs) and length-length relationships (LLRs) of Sillaginopsis panijus (Hamilton, 1822) were investigated in the Indian coast of north-western Bay of Bengal. Altogether 622 specimens were collected between August 2018 and September 2019 from landings by trawls (30-35 mm mesh size), gillnets (15-55 mm mesh size) and shore seines (7-15 mm bag mesh size). The total length and weight of the specimens ranged from 7.8-40.3 cm and 2.9-506 g, respectively. The LWR established was W=0.0048 L3.059 for males, W=0.0032 L3.185 for females and W=0.0047 L3.0645 for indeterminates, indicating positive allometric growth pattern. All the LWRs were highly significant (p&lt;0.001, r2≥0.977). The highest coefficient of correlation (r) was observed for total length against fork length (0.999) and lowest for head length against eye diameter (0.951). The fin formula was expressed as D1 X, D2 I + 24-28, P 17-22, V I + 5, A II + 25-27, GR 2-3/6-9. The study provides the first detailed account of the biometric relationships of S. panijus in the north-western Bay of Bengal, which can be used as baseline information for subsequent biological and population based studies in the region.

Size Frequency, Length-Weight, and Length-Length Relationship of Bearded Worm Goby Taenioides cirratus (Blyth, 1860) from the Noakhali Coast, Bay of Bengal

Size frequency, length-weight relationships (LWRs), and length-length relationships (LLRs) for an estuarine fish Taenioides cirratus (Blyth, 1860) from the Noakhali coast, Bay of Bengal was studied. Specimens were caught with the fixed purse net of two mesh sizes (0.2 to 0.5 in. and 2.0 to 2.5 in.) from March to July 2019. The maximum total length for male T. cirratus (36.2 cm) reported in this study is a new record for this species. The length-weight relationships for male, female, and unsexed T. cirratus was highly significant (p < .001), and adjusted r2 values were 0.967, 0.922 and 0.955 for males, females, and unsexed, respectively. The calculated growth coefficient (b) for male, female, and unsexed T. cirratus was 2.546, 2.948, and 2.618, respectively. The length-length eq. TL = 1.1974 SL + 0.4403 for the males and TL = 1.1712 SL + 0.7096 for the females were highly significant (p = 0.001, r2 ≥ 0.978 for both males and females). Our estimated LWRs and LLRs parameters for male and female T. cirratus can be useful for the management and conservation purpose of this species.

Some population parameters of Bengal yellowfin seabream, Acanthopagrus longispinnis (Val.), from Hatiya Island, Bay of Bengal

Abstract Size frequency, length-weight relationships (LWRs), length-length relationships (LLRs), and relative condition factor (Kn) was studied in an estuarine fish the Bengal yellowfin seabream, Acanthopagrus longispinnis (Val.), from Hatiya Island in the Meghna River estuary. Specimens were caught with fixed purse nets of two mesh sizes (0.2 to 0.5 inch and 2.0 to 2.5 inch) from January to March 2020. The total body length of A. longispinnis ranged between 5.8 and 9.3 cm throughout the sampling period. The length-weight relationships for A. longispinnis was highly significant (p &lt; .001), and the adjusted r 2 value was 0.921. The calculated growth coefficient (b) for A. longispinnis was 3.163, which indicated a hyperallometric growth pattern. The length-length equation TL = 1.1384 SL + 0.4899 for unsexed A. longispinnis was highly significant (p = 0.001, r2 = 0.951). There were no significant variations in relative condition factors among the specimens of different length classes (5.5–9.5 cm). No information regarding length-weight or length-length relationships for A. longispinnis was previously reported in FishBase. Our estimated LWR and LLR parameters for A. longispinnis can be useful for management and conservation purposes of this estuarine species.