Length-weight Parameters Research Articles

Length-weight relationship of ten species of Leuciscinae sub-family (Cyprinidae) from Iranian inland waters

In this study, the length-weight relationships (LWRs) were estimated for 697 specimens belonging to ten species of Leuciscinae subfamily, viz. Squalius berak, S. namak, S. turcicus, Acanthobrama marmid, A. microlepis, Chondrostoma esmaeilii, Leuciscus latus, Alburnus doriae, Leucaspius delineates and Blicca bjoerkna from Iranian inland waters, including the Persian Gulf, Caspian Sea, Namak Lake, Dasht-e Kavir, Hari River and Isfahan basins. Total length and total weight of the examined specimens ranged 3.8-27.8 cm and 0.59-247 g, respectively. Fishes were collected using electrofishing device between July 2010 and August 2017. This study represents the first reports of LWRs data for A. doriae, C. esmaeilii, L. latus and L. delineates. The length-weight parameter b found to be 2.75 (A. microlepis) - 3.44 (B. bjoerkna) with regression coefficients (r2) ranging 0.87 to 0.99 for the studied fishes. The student’s t-test showed all studied species have a positive allometric growth pattern except A. doriae (isometric) and A. microlepis (negative allometric).

Population structure of Nile tilapia and its impact on fisheries of a tropical impacted reservoir, Central India

Length-frequency data of Nile tilapia (Oreochromis niloticus) was studied using 1250 specimens of both sexes combined with maximum length and weight of 44.5cm (TL) and 1050g respectively through gill net catch at different landing sites of Halali Reservoir, Madhya Pradesh. The data were grouped into classes of 10-mm intervals and various parameters of population dynamics of fish were analysed and computed using the FiSAT-II software package (FAO-ICLARM Stock Assessment Tools). The length-weight parameters were found to be at W = 0.001L 2.96 where b = 2.96 and a = 0.001. Growth parameters L∞ and K of the species were L∞ = 46.73cm and K= 0.63/year respectively; the annual rates of natural (M) and fishing mortality (F) were found to be 0.60 and 0.72 respectively. The estimated values for the exploitation rate (E) using the length-converted catch curve and virtual population analysis were 0.54 and 0.42 respectively. The recruitment pattern shows that O. niloticus was recruited in the fishery during April with one peak. Based on the data analysis, the stock in the Halali Reservoir does not exceed the maximum fishing pressure (Emax = 0.55) and there is selective mortality towards adult fish sizes. The introduction of Nile tilapia improved the total catch per unit of effort (CPUE), as well as increased the number of active fishers. Conversely, a significant reduction in the CPUE of other commercially important indigenous species was observed after the introduction of Nile tilapia in the reservoir. Therefore, for management purpose, this study suggests that the existing effort in terms of gill net mesh size which target size (TL-15.0 to 25.0cm) individuals of length group is to be increased to exert more fishing pressure on Nile tilapia population in the reservoir to decline its abundance in the long term.

Biometric relationships for commercially important penaeid shrimp species on the east coast of the Gulf of California

Biometric relationships were estimated for the three most important shrimp species on the coasts of the Gulf of California, Mexico. Individuals were obtained from six lagoon systems, and offshore sites along the east coast of the Gulf of California, mainly in the state of Sonora, between March and September of 2015 and 2016. A total of 25,764 individuals of Penaeus stylirostris , Penaeus vannamei and Farfantepenaeus californiensis were analyzed; the length and weight regression for the females, males and combined sexes showed a high correlation between variables. Additionally, some statistically significant differences were found in the linear length and weight relationships ( P < 0.05) between sexes. This study reports the length-weight parameters for a key site of the shrimp fishery, it covers a wide range of sizes for each species and was based on the stages late inshore juvenile and offshore of the shrimp lifecycle; as such, this study provides useful information for future estimations of indispensable parameters for stock assessment analyses.

Invasion of non-indigenous suckermouth armoured catfish of the genus Pterygoplichthys (Loricariidae) in the East Kolkata Wetlands: Stakeholders’ perception

Rapid spread and population increase of suckermouth armoured catfishes belonging to the genus Pterygoplichthys(Loricariidae) in the East Kolkata Wetlands (EKW) in recent times is of increasing concern, because of the notable possibility that these non-native catfishes are adversely affecting fish germplasm and commercial fishery of this unique ecosystem. To study the present status of these loricariids and the invasion and impact dynamics in EKW ecosystems, field survey was conducted over a water spread area of 670 ha, comprising 120 fishermen (N2 = 120) of 30 farms (N1 = 30), between February and October, 2017 through a pre-tested, open-ended structured schedule. A total of 943 specimens of Pterygoplichthysspp. were collected and analysed for abundance, length-weight parameters, gonado-somatic index and relative fecundity. Pterygoplichthysspp. occurred at 29 (97%) of 30 surveyed farms and approximately 70% of the farm owners perceived that these fishes posed moderate to serious economic impact. Fish production cutback, small indigenous fish (particularly,Puntius spp.) depredation and bottom structure alteration are among the major negatives perceived; a positive note in terms of soil-bound nutrient release was reported by a few fishermen (1%). Channel through which sewage water intake occurred by gravitation has been perceived to be the main route of entry (77%), with significantly higher abundance around the periphery of the pond. Almost 80% respondents perceived an increased occurrence of these fishes over the last four years, with seasonal pattern of abundance. While culling of suckermouthafter harvest was the most common method adopted to reduce population, multi-layer screening in the inlet of sewage water into pond is perceived as most sought solution for control. Average direct and indirect financial losses due to Pterygoplichthys spp. in EKW was calculated as`0.092 lakh ha-1yr-1, which points towards mounting pressure of loricariids in already dwindling economics and biodiversity of EKW.

Fishery of Sinop Coasts in the Black Sea Surveys

DOI : 10.26650/EuroJBiol.2018.388175 Objective : The current work was carried out between 2013-2014 during the fishing periods to evaluate certain fish aggloremations within 3 miles of the coastal zone. Therefore, some basic characteristics of fish populations along the Inceburun coast of the Sinop province of the Black Sea were examined. Materials and Methods : Data was collected from 5 trawl operations in the Sinop-Inceburun Region of the Black Sea at depths of 20 to 39 meters at 5 different locations. Biometric measurements of each species was made. A literature search was performed to gather information about the status of threatened fish species found in the region. The length-weight parameters of 4 commercial fish species were estimated. Results : During the fishing season between 1st September 2013 and 15th April 2014 different fish species were captured depending on the season and climate. In these surveys, 16 teleost species from 15 families, 2 elasmobranch species from 2 families and 2 species of invertebrates were recorded from 5 different stations. In these surveys random samples of red mullet, bluefish, horse mackerel, turbot etc. were collected from 5 different stations. The total mean CPUA was estimated at 425.30 kg/km2. Conclusion : The Black Sea areas including those around the Sinop coast have an important effect on the entire production of sea fish of the Turkish fishery. In addition, Sinop fisheries generate significant fishery production supporting logistics and employment. In the Sinop peninsula, there is an increasing trend towards the production of commercial species of the Black Sea.

Optimum Harvest Time of the Nile Tilapia (Oreochromis niloticus) in Honduras: A Two Step OLS Procedure to Obtain the Growth Function

Several aquaculture firms in Honduras lack a profit function for tilapia production, which complicates their decision-making. Furthermore, several statistical procedures used to obtain a production function are too complex for these firms to implement on their own. Thus, a simple, yet efficient, model was developed for these firms to follow. The model for this function consists of a gross-margin function composed of an income and a cost function. The OLS procedure in this model differs from several studies by using the OLS obtained length-weight parameter, “b” as an input to estimate “k” in a second OLS regression. The latter regression is applied to a log-lin model of a weight-based von Bertalanffy growth function. The estimated length-weight exponent, “b” used in the growth function, the growth parameter per day, “k” and the mortality parameter per day, “z” are 2.92289, 0.00821 and 0.00086 respectively. The optimum harvest time estimated for one period is 199 Days after Stocking (DAS) when there is no restriction in the market for the size of fish and 208 DAS when minimum market length is 20 cm. The optimum harvest time for infinite time horizon is 117 DAS if there is no size restriction.

Status of Atlantic Salmon (Salmo salar L.) reproduction in the Zolotitsa river, Paraninsky tributary, and the adjacent Lopatka stream in Onezhskoye Pomorye National Park (White Sea drainage basin)

The salmon spawning river Zolotitsa, its small tributary Paraninsky, and adjacent stream Lopatka were surveyed (11 sites in total) in Onezhskoye Pomorye National Park (White Sea drainage basin, joined to Kenozersky NP since 2016). The distribution of the Atlantic Salmon and conditions in its habitats were determined for the first time. The distribution densities of parr of different age categories were estimated. The average value was 59 fish/100 m2, which is above the average (50 fish/100 m2) across spawning rivers of Northwest Russia. The density of 0+ salmon varied among river sites from 13 to over 200 fish/100 m2 (August), and the rest of the population, with 25 fish/100 m2 average density in all 11 sites, was represented by older parr (1+, 2+, 3+). The biological characteristics of the river component of the Atlantic salmon population are given: ratios of different age classes, and length-weight parameters of the fish. Rapids in the river upper course were found to have a potentially insufficient juvenile salmon population. We suggest intensifying brooder protection during spawning migrations.

Length-weight and length-length relationships of three Blenny species from the Persian Gulf and the Gulf of Oman

The present study provides the length–weight and length–length relationships information (LWR & LLR) for three Blenny species; Antennablennius adenensis from the coast of Larak Island in the Persian Gulf and Istiblennius pox and Omobranchus mekranensis, which were captured in the coasts of Chabahar city in the Gulf of Oman, Iran. Total length (TL) and standard length (SL) were determined as well as weight. Specimens were collected occasionally in summer 2017 and winter 2018 by Hand net. The length–weight parameter b for these species was 2.84, 3.29 and 3.06 respectively with a high coefficient of determination (r2 ≥ 0.95). All LLRs were highly correlated (r2 > 0.99). All three species had no previous report for LWR and LLR estimates in FishBase.

Length-weight relationships for small Midwestern US fishes

Herein, we provide length-weight relationships for juvenile and smallbodied freshwater fishes of 20 species. Length-weight parameters were estimated using data collected through four years of electrofishing surveys conducted in the rivers of Illinois, USA.

RELATIONSHIP BETWEEN SIZE AND THE RATE OF CALCIUM–DEPENDENT PROTEOLYSIS IN SKELETAL MUSCLES IN THE ATLANTIC SALMON (SALMO SALAR L.) AND BROWN TROUT (SALMO TRUTTA L.) FROM RIVERS DRAINING TO THE WHITE SEA (ARKHANGELSK REGION)

The activity level of calcium-dependent proteases of the calpain family in skeletal muscles of the atlantic salmon ( Salmo salar L.) and brown trout ( Salmo trutta L.) from some watercourses (the Zolotitsa River and Lopatka stream) draining to the White Sea (arkhangelsk region) was estimated. a correlation between length-weight parameters of the fish and the rate of calcium-dependent proteolysis in their skeletal muscles was demonstrated. atlantic salmon parr from the Zolotitsa River were larger and had a higher growth rate compared to salmon of the same age from rivers of the Murmansk Region. The comparison of length-weight parameters and data on the rate of calcium-dependent proteolysis in brown trout parr from three watercourses draining to the White Sea and Lake Onego rev ealed the lowest growth rate in fish aged 3+, 4+ from the Lopatka stream. The obtained results indicate that the growth rate of salmonids S. salar and S. trutta depends on the environmental condition and availability of food resources in the studied waters.

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 relationships of five mullet fish species from the Southern Taiwan coast

The length–weight relationships (LWRs) are described for five fish species, Liza affinis (Gunther, 1861), Liza alata (Steindachner, 1892), Chelon subviridis (Valenciennes, 1836), Chelon macrolepis (Smith, 1846) and Oedalechilus labiosus (Valenciennes, 1836), obtained from Southern Taiwan coast during July 2013 to October 2016.The length–weight parameter b for these species ranged from 2.734 to 2.974, with regression coefficients (r2) ranging from 0.966 to 0.979.

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 relationships of three indigenous fishes collected from Ranganadi River of Lakhimpur district, Assam, India

Summary Length-weight relationships (LWR) were estimated for three species of fishes, namely Amblyceps arunchalensis, Nath & Dey, 1989, Botia rostrata Gunther, 1868, and Esomus danrica (Hamilton, 1822) inhabiting the Ranganadi river in Lakhimpur district of Assam, India. A total of 400 specimens (A. arunchalensis – 33, B. rostrata- 53, and Esomus danrica – 314) were collected during irregular intervals between January 2013 and December 2015 using a cast net of 2–10 mm mesh sizes and 2–2.5 m length. The length–weight parameter b ranged from a minimum of 2.95 for E. danrica to a maximum of 3.14 for B. rostrata, with regression coefficients (r2) ranging from0.966 to .993. Prior to this study, the LWRs for B. rostrata E. danrica and A. arunchalensis were unknown. A new maximum length is reported for A. arunchalensis.

Protein degradation systems in the skeletal muscles of parr and smolt Atlantic salmon Salmo salar L. and brown trout Salmo trutta L.

Although protein degradation limits the rate of muscle growth in fish, the role of proteolytic systems responsible for degrading myofibrillar proteins in skeletal muscle is not well defined. The study herein aims to evaluate the role of calpains (calcium-activated proteases) and proteasomes (ATP-dependent proteases) in mediating muscle protein turnover at different life stages in wild salmonids. Protease activities were estimated in Atlantic salmon (Salmo salar L.) and brown trout (Salmo trutta L.) parr and smolts from the Indera River (Kola Peninsula, Russia). Calpain and proteasome activities in Atlantic salmon skeletal muscles were lower in smolts as compared with parr. Reduced muscle protein degradation accompanying Atlantic salmon parr-smolt transformation appeared to provide intense muscle growth essential for a minimum threshold size achievement that is required for smoltification. Calpain and proteasome activities in brown trout parr and smolts at age 3+ did not significantly differ. However, calpain activity was higher in smolts brown trout 4+ as compared with parr, while proteasome activity was lower. Results suggest that brown trout smoltification does not correspond with intense muscle growth and is more facultative and plastic in comparison with Atlantic salmon smoltification. Obtained data on muscle protein degradation capacity as well as length-weight parameters of fish reflect differences between salmon and trout in growth and smoltification strategies.

Length-weight and length-length relationships for 11 species of the genusAlburnoidesJeitteles, 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 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).

Resilience of Key Biological Parameters of the Senegalese Flat Sardinella to Overfishing and Climate Change

The stock of the Senegalese flat sardinella, Sardinella maderensis, is highly exploited in Senegal, West Africa. Its growth and reproduction parameters are key biological indicators for improving fisheries management. This study reviewed these parameters using landing data from small-scale fisheries in Senegal and literature information dated back more than 25 years. Age was estimated using length-frequency data to calculate growth parameters and assess the growth performance index. With global climate change there has been an increase in the average sea surface temperature along the Senegalese coast but the length-weight parameters, sex ratio, size at first sexual maturity, period of reproduction and condition factor of S. maderensis have not changed significantly. The above parameters of S. maderensis have hardly changed, despite high exploitation and fluctuations in environmental conditions that affect the early development phases of small pelagic fish in West Africa. This lack of plasticity of the species regarding of the biological parameters studied should be considered when planning relevant fishery management plans.

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).

Population structure and reproductive period of two introduced fish species in a Brazilian semiarid region reservoir.

The Amazonian fish species Plagioscion squamosissimus (Sciaenidae) and Cichla monoculus Cichlidae), have been widely introduced into different reservoirs in Brazil, and have caused many negative mpacts on local fish fauna. The aim of this study was to evaluate the population structure (abundance, length structure, length-weight relationship, sex ratio, and length at first maturity) and the reprodutive period of these wo species in the Santa Cruz Reservoir (built in 2002), located in the Brazilian semiarid region, for their adequate management and local species conservation policies. Specimens were collected quarterly in eight sites from February 2010 to November 2013 using gillnets (12 to 70 mm mesh between adjacent knots). The specimens captured were counted and the following biometric and biological data were analysed: standard length, total weight, and reproductive data, such as, sex, weight and gonadal maturity stage. The species abundances were estimated by CPUE and expressed as the number of individuals per gill net area x gill net exposition time (m2 x h); length frequency histograms were built with intervals of 5 cm. The length-weight parameters were estimated with a linear regression after a logarithmic transformation of the data. With the reproductive data we estimated sex ratio, reproduction period and length at first maturity (L50). We captured a total of 1,071 specimens of P. squamosissimus and 156 specimens of C. monoculus. Both species showed higher abundances in 2010, 0.004306 m2 x h and 0.00022 m2 x h, respectively, but this parameter decreased from 2010 to 2013. Standard length ranged between 6.4 and 46.2 cm for P. squamosissimus (20.025.0 cm was the most frequent class), and 7.0 and 38.7 cm for C. monocidus (10.0-15.0 cm was the most frequent class). The length-weight relationships were described by the following equations: log10Wt = -1.8349+3.0899log10Lp and R2= 0.9795 for P. squamosissimus, and log10 Wt = -1.7944+3.0885log10Lp and Wt = 0.0160 and R2 = 0.9929 for C. monoculus; both species exhibited positive allometric growth. The sex ratio for both species differed from 1:1, with a predominance of females for P. squamosissimus and males for C. monoculus. The Lp50 was estimated to be 15.90 cm for P. squamosissimus and 15.65 cm for C. monoculus, and the reproductive data indicated that both species reproduced throughout the year. We concluded that although the population of both species reduced their abundance over the study period, P. squamosissimus and C. monoculus are established and structured populations in the Santa Cruz Reservoir with individuals growing satisfactorily and reproducing in all seasons, without a well-defined reproductive peak. We suggest that the managers may allow the artisanal and/or sport fisheries of these species.