scholarly journals Population Dynamics of Horse Mackerel (Trachurus Mediterraneus Ponticus) in the Bulgarian Black Sea Coast

ISRN Zoology ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Maria Yankova
Keyword(s):  
Black Sea ◽  
Growth Parameters ◽  
Total Mortality ◽  
Growth Function ◽  
Horse Mackerel ◽  
The Black Sea ◽  
Growth Coefficient ◽  
Von Bertalanffy Growth Function ◽  
Black Sea Coast ◽  
Commercially Important

The horse mackerel Trachurus mediterraneus is a commercially important pelagic fish species in the Black Sea fishery. The present investigation was carried out between May and December 2010 along the Bulgarian coast of the Black Sea. Population parameters of horse mackerel from the trawl and fishing nets catches were estimated from length frequency data, by using ELEFAN-I computer program. The ELEFAN-I analysis gave the following Von Bertalanffy Growth Function (VBGF) parameters: the asymptotic length  cm, growth coefficient value was , and the hypothetical age at which length is zero was . Based on these growth parameters, the total mortality coefficient () during the study period was estimated to be 2.99. The estimated value for natural mortality () was 1.08; hence, the fishing mortality coefficient () was 1.91. The estimated value for the exploitation rate () using the length converted catch curve was 0.64. The estimated sizes of T. mediterraneus at 25, 50, and 75 percent probabilities of capture were 16.80 cm, 18.72 cm, and 20.64 cm, respectively.

scholarly journals Growth, Mortality and Exploitation Levels of Sphyraena sphyraena (Pisces: Sphyraenidae) and Apsilus fuscus (Pisces: Lutjanidae) in Ghanaian Waters

2021 ◽  
Vol 2 (1) ◽  
pp. 16-23
Author(s):  
Joseph Aggrey-Fynn ◽  
Divine Worlanyo Hotor
Keyword(s):  
Growth Parameters ◽  
Total Mortality ◽  
Growth Function ◽  
Frequency Data ◽  
Length Frequency ◽  
Fish Stocks ◽  
Von Bertalanffy Growth Function ◽  
Inshore Waters ◽  
The Mean ◽  
Length Frequency Data

Sphyraena sphyraena (Linnaeus, 1758) and Apsilus fuscus (Valenciennes, 1830) are commercially important fish species in Ghana. The stocks are exploited mainly by the artisanal and semi-industrial fisheries. Growth and mortality rates, and exploitation levels of the two stocks in inshore waters of Ghana were assessed as a contribution to fill the knowledge gap on the species. Samples were obtained from three landing sites along the coast of Ghana from February to July, 2017. Length-frequency data were used to estimate growth, mortality and exploitation ratios. The modal class for S. sphyraena was 37.0–39.9 cm total length (TL) and 34.0–35.9 cm TL for A. fuscus. The length and weight relationships established that growth in S. sphyraena was negative allometric, whereas that of A. fuscus was isometric. The estimated growth parameters from the length frequency data fitted with the von Bertalanffy growth function were asymptotic length (L∞) of 69.9 cm TL for S. sphyraena and 53.5 cm TL for A. fuscus. The growth constant (K) was calculated as 1.64 yr-1 for S. sphyraena and 0.50 yr-1 for A. fuscus. The mean length-at-first capture (Lc) was found to be lower than the mean length at sexual maturity (Lm) for both species. The sex ratio showed a dominance of females over males in S. sphyraena, and 1:1 for A. fuscus. The total mortality rate (Z) for S. sphyraena was more than for A. fuscus. The estimated natural mortality (M) was 1.88 yr-1 for S. sphyraena and 0.74 yr-1 for A. fuscus whilst fishing mortality (F) rate was 3.04 yr-1 for S. sphyraena and 0.93 yr-1 for A. fuscus. The exploitation ratio showed that both fish stocks were exploited over the optimum levels. The estimated population parameters of the species obtained from the study, therefore, might be useful for the sustainable management of the stocks.

Length‐Weight Relationship (LWR), Growth estimation and Length at maturity of Eleutheronema tetradactylus in the Chilika Lagoon, India

2012 ◽  
Vol 2 (3) ◽  
pp. 97-102
Author(s):  
S. K. Karna ◽  
D. K. Sahoo ◽  
S. Panda
Keyword(s):  
Growth Parameters ◽  
Fork Length ◽  
Growth Function ◽  
Chilika Lagoon ◽  
Growth Coefficient ◽  
Logistic Equations ◽  
Weight Relationship ◽  
Von Bertalanffy Growth Function ◽  
Growth Estimation ◽  
Future Management

An attempt was made to study the length‐weight relationship (LWR), growth and length at 50% maturity (L50) of Eleuthronema tetradactylus (Sahala) in Chilika lagoon, which will helpful for the future management of the stocks as well as the lagoon. For LWR study, a total of 255 fish specimens collected from April 2008 to May 2009 of which fork length (FL) and body weight (BW) were measured to the nearest 0.1cm and 0.01g respectively. The equation, y = 4E‐06x3.115 found from the study where the computed condition factor (a), growth coefficient (b) and regression coefficient (r2) were 4E‐06, 3.115 and 0.996 respectively. In total, 3356 number of specimen measured to study growth of the species. The estimated growth parameters found from von Bertalanffy Growth Function (VBGF) i.e., Linf(cm), K, and t0 were 78.1cm, 0.15, and ‐0.47 respectively. Logistic equations used to estimate the length at 50% maturity (L50) of a total of 68 specimens, sampled from April 2008 to May 2009. The estimated L50 was 315mmFL.

scholarly journals The first data on the population parameters and morphometry of Mesogobius batrachocephalus (Pallas 1814) (Family: Gobiidae) in the southern Black Sea

2021 ◽  
Vol 4 (2) ◽  
pp. 116-128
Author(s):  
Mehmet Aydın
Keyword(s):  
Black Sea ◽  
Growth Parameters ◽  
Average Length ◽  
Gonadosomatic Index ◽  
Total Mortality ◽  
Mesh Size ◽  
The Black Sea ◽  
Population Parameters ◽  
The Caspian Sea ◽  
Female Ratio

Knout goby, Mesogobius batrachocephalus Pallas, 1814, which belongs to Gobiidae, inhabits in the Black Sea, Sea of Azov, the Caspian Sea and the rivers that flow in these three seas. The major population parameters and morphometry of Mesogobius batrachocephalus from the coasts of the southern Black Sea were investigated in this study. A total of 641 individuals were sampled between January 2019 and December 2019 between the depths of 2 to 120 m depth by using a trammel net with a mesh size of 17-24 mm. The average length and weight values were calculated as 23.1 cm (5.3-34.0) and 130.1 g (1.34-377.54) respectively. The male to female ratio of the population was found as 1:0.91 (P>0.05). Age of sampled 641 individuals varies between zero and seven. For all the sampled individuals, the von Bertalanffy growth parameters were calculated as; L∞ = 38.2 cm, k = 0.245 year-1 and t0 = -1.873 year and the length-weight relationship was found as W = 0.0058 TL3.148. Total mortality (0.481), natural mortality (0.466), fishing mortality (0.015), growth performance index (2.55) and condition factor (0.913) were calculated. The maximum value of gonadosomatic index was reached in March. Average relative fecundity was found to be 118.3 eggs per g (78.9-234.5), while the average diameter of the eggs was found as 2733.0 µm ±221.18 (2287.1-3097.8). This study provides the first data on the population parameters and the morphometry of Mesogobius batrachocephalus. These data could contribute to the establishment of a sustainable management plan for fisheries resources in the Black Sea.

Age and growth of the threatened endemic skate Rioraja agassizii (Chondrichthyes, Arhynchobatidae) in the western South Atlantic

2019 ◽  
Vol 70 (1) ◽  
pp. 84 ◽  
Author(s):  
F. P. Caltabellotta ◽  
F. M. Silva ◽  
F. S. Motta ◽  
O. B. F. Gadig
Keyword(s):  
Growth Parameters ◽  
Management Strategies ◽  
Information Criterion ◽  
Growth Function ◽  
South Atlantic ◽  
Age And Growth ◽  
Biological Information ◽  
Growth Coefficient ◽  
Von Bertalanffy Growth Function ◽  
Best Fit

The Rio skate Rioraja agassizii is a threatened endemic skate species frequently caught as bycatch in the western South Atlantic. However, there is no biological information about its age and growth parameters, which would be necessary to provide science-based information for the development of management strategies for this species. The aim of the present study was to provide information about the age and growth parameters of R. agassizii. In all, 138 vertebrae from individuals ranging in size from 9.0 to 53.2-cm total length (TL) were analysed. The edge analysis indicated a trend for annual band deposition in the vertebrae. Maximum ages estimated for males and females were 6 and 10 years respectively. Akaike’s information criterion indicated that the modified two-parameter form of the von Bertalanffy growth function (using length at birth L0=9.0cm TL) provided the best fit, with derived parameters of theoretical maximum length L∞=49.6cm TL and growth coefficient k=0.27 for males and L∞=59.0cm TL and k=0.22 for females. Our results are important to understanding the resilience of this skate species to harvest, which can contribute to the development of fisheries management strategies and conservation programs.

Population dynamics of an inarticulate brachiopod Lingula unguis on the intertidal flats of Kunsan, Korea

2000 ◽  
Vol 80 (3) ◽  
pp. 429-435 ◽  
Author(s):  
K.Y. Park ◽  
C.W. Oh ◽  
S.Y. Hong
Keyword(s):  
Growth Parameters ◽  
Total Mortality ◽  
Size Composition ◽  
Growth Function ◽  
Spatial And Temporal Variation ◽  
Estimation Of Parameters ◽  
Recruitment Pattern ◽  
Intertidal Flats ◽  
Von Bertalanffy Growth Function ◽  
Spatial Differences

Investigations were made on spatial and temporal variation, population structure, growth, recruitment and mortality in the intertidal flats of Kunsan (Korea, Yellow Sea) of an inarticulate brachiopod Lingula unguis. Statistical analysis indicates significant spatial differences and a significant relationship between density and ratio of sands to silts, suggesting that the distribution and density of this species were related to particle size. The population consisted of three year-classes, with a similar size composition each year, of which the second year-class was a major component. From estimation of parameters of growth monthly length–frequency was analysed by ELEFAN. Parameters of growth were estimated, using the modified von Bertalanffy growth function (VBGF) model incorporating seasonal variation in growth. The growth parameters are: L∞=44.00 mm SL, K=0.88 y−1, C=0.90, WP=0.48. The recruitment pattern shows two major recruitments per year. The maximum life span is estimated as 3.45 y. Total mortality (Z) by length-converted catch curve was estimated at 3.65 y−1. The population mainly occurred in fine sands and exhibited patchy distribution.

MORPHOLOGY AND DYNAMICS OF THE LIMANIC BARRIERS ALONG THE BLACK SEA COAST UNDER ACTIVE ANTROPOGENOUS IMPACT

2018 ◽  
Author(s):  
Г. Выхованец ◽  
G. Vyhovanec
Keyword(s):  
Black Sea ◽  
The Black Sea ◽  
General Tendency ◽  
Sea Sand ◽  
Black Sea Coast ◽  
Sea Coast

Typical coastal elements of limans and lagoons are barriers, that separate limanic aquatories from a Seas. On limanic shores structure of the Black Sea sand barriers represented three longitudinal landscape “zones”: sea beach (“frontal”), dune-aeolian and limanic (“back of the barrier”). They closely interactive between themselves under influence of lithodynamical exchanges of sediment. General tendency of the barriers dynamics is displacement to Land direction.

A new cave-dwelling species of the genus Cimmerites Jeannel, 1928 (Coleoptera: Carabidae: Trechini) from the West Caucasus

2011 ◽  
Vol 20 (1) ◽  
pp. 48-53
Author(s):  
I.A. Belousov ◽  
A.G. Koval
Keyword(s):  
New Species ◽  
Black Sea ◽  
Life Form ◽  
Intermediate Position ◽  
The Black Sea ◽  
The West ◽  
Black Sea Coast ◽  
A New Species ◽  
Sea Coast

A new species of the genus Cimmerites Jeannel, 1928, C. maximovitchi sp. nov., is described from the Akhunskaya Cave and Labirintovaya Cave, both located in the Akhun Karst Massif on the Black Sea Coast of the West Caucasus (Krasnodar Territory, Russia). The new species is rather isolated within the genus Cimmerites and occupies an intermediate position between species related to C. kryzhanovskii Belousov, 1998 and species close to C. vagabundus Belousov, 1998. Though both C. maximovitchi sp. nov. and C. kryzhanovskii are still known only from caves, these species are quite similar in their life form to other members of the genus which are all true endogean species.

THE APPLICATION FEATURES AN INTEGRATED ASSESSMENT METHOD FOR THE ANALYSIS OF TOURIST AND RECREATIONAL CAPACITY ON THE EXAMPLE OF THE MUNICIPALITY OF TUAPSINSKY DISTRICT

2017 ◽  
Author(s):  
Mikael Arakelov ◽  
Mikael Arakelov ◽  
Arthur Arakelov ◽  
Arthur Arakelov
Keyword(s):  
Black Sea ◽  
Russian Federation ◽  
Integrated Assessment ◽  
Assessment Method ◽  
The Black Sea ◽  
Regional Management ◽  
Black Sea Coast ◽  
The Russian Federation ◽  
Tourism Potential ◽  
Sea Coast

Tourism is one of the most dynamically developing branches of economy in the Russian Federation in general and on the Black Sea coast in particular, in this regard, the assessment of tourism potential is one of the most important tasks of regional management.

Sign in / Sign up

Export Citation Format

Share Document