scholarly journals POPULATION DYNAMICS OF THE EDIBLE ROCK OYSTER SACCOSTREA CUCULLATA (BORN, 1778) ALONG THE SOUTH-WEST COAST OF INDIA

2020 ◽  
Vol 67 (1) ◽  
Author(s):  
S. Yambem Tenjing
Keyword(s):  
Population Dynamics ◽  
Coastal Waters ◽  
South India ◽  
Total Mortality ◽  
Growth Coefficient ◽  
South West ◽  
Rock Oyster ◽  
Saccostrea Cucullata ◽  
Karnataka State ◽  
South West Coast

For the management of molluscan stocks, knowledge of various population parameters and exploitation level of the population are needed. The present study assessed the population dynamics on the rock oyster Saccostrea cucullata (Born, 1778) in Karnataka State, south India. The specimens of S. cucullata were collected from Baindur rocky beach at monthly intervals from June 2010 to May 2011. Asymptotic length (L∞) estimated was 57.8 mm and growth coefficient (K) was estimated at 1.4 year-1. The sizes attained were 45.30, 54.72 and 57.04 mm at the end of first, second and third years of age, respectively. Total mortality (Z) was 5.24 year-1. Natural mortality (M) and fishing mortality (F) were 1.40 and 3.84 year-1 respectively. The life span of S. cucullata was estimated as 2.5 years approximately. Exploitation level (E) was computed as 0.73, indicating that the fishery of S. cucullata in the coastal waters of Karnataka Is overexploited.

Status of population dynamics of the Asian wedge clam, Donax scortum (Bivalvia: Donacidae): a first report from Asia

2016 ◽  
Vol 97 (8) ◽  
pp. 1635-1642 ◽  
Author(s):  
Yambem Tenjing Singh
Keyword(s):  
Population Dynamics ◽  
Coastal Waters ◽  
Sandy Beach ◽  
Stock Assessment ◽  
Total Mortality ◽  
Assessment Tools ◽  
Fishing Mortality ◽  
Population Parameters ◽  
Growth Coefficient ◽  
June July

For the management of mollusc resources, knowledge of various population parameters and exploitation level of the population of wedge clams are needed. Population dynamics on wedge clam, Donax scortum is still unknown in Asia. FAO-ICLARM Stock Assessment Tools (commonly known as FiSAT) was used for calculating population parameters of this species. The specimens of D. scortum were collected from Padukere sandy beach at monthly intervals from February 2009 to January 2010. Asymptotic length (Lα) was 70.88 mm and growth coefficient (K) was estimated at 0.64 year−1. The sizes attained by D. scortum were 33.51, 51.17, 60.49, 65.40, 67.99 and 69.36 mm at the end of first, second, third, fourth, fifth and sixth years of age, respectively. Density of clams ranged from 2 ind. m−2 (June, July and August) to 8 ind. m−2 (December). Biomass (total weight) of clams ranged between 10.084 g m−2 (August) to 185.100 g m−2 (December). Total mortality (Z) for D. scortum was 3.20 year−1. Natural mortality (M) and fishing mortality (F) were 0.64 year−1 and 2.56 year−1 respectively. Exploitation level (E) was computed as 0.80, indicating that the fishery of D. scortum in the coastal waters of Karnataka is overexploited.

scholarly journals Some Aspect on the Biology of Pen Shell Atrina Pectinata (Linneaus, 1767) In Coastal Waters of Maqueda Bay, Philippines

2019 ◽  
Vol 2 (2) ◽  
Keyword(s):  
Coastal Waters ◽  
Total Mortality ◽  
Condition Index ◽  
Recruitment Pattern ◽  
Spawning Period ◽  
Growth Coefficient ◽  
Measurement And Analysis ◽  
Pen Shell ◽  
Atrina Pectinata

A Total of 379 pen shells Atrinapectinata were collected from February 2017 to January 2018 in the coastal waters of Maqueda Bay. Measurement and analysis of length and weight were done using FiSAT software. Population parameters were assessed to evaluate the stock status which includes the asymptotic length (L∞) and growth coefficient (K) to be 34.65 cm, 0.77 year−1 respectively. Specimens of A. pectinata reached a mean length of 20.98 cm. Length-weight relationship resulted to “negative allometric” 0.0462L2.6533 R2 = 0.7823; signifying pen shells growth was faster in length than on weight. The recruitment pattern was continuous over the year with one major peak during rainy season (July). In addition, the highest catch based on collected sampling date catch was during summer, which suggest as the peak season of the species in the area. Furthermore, the average catch annually of hookah diver was 17.69208. Higher condition index was recorded from April to May, September and January, indicating the high quality of pen shell meat and is recommended as the best period to harvest pen shell whereas June to August and October to December can be concluded as the spawning period of the pen shell and the ideal period to institute close season. Further analysis revealed that the pen shell was nearly facing overexploitation with the exploitation rate (E = 0.46) mainly due to lack of a minimum limit size and also due to an increase in the harvesting effort. The estimated total mortality (Z), natural mortality (M) and fishing mortality (F); 1.36 year−1, 1.01year−1 and 0.62 year−1, respectively. Using the mentioned (Z), (M), (F) and (E), the total population resulted to 84725.7 suggesting that half of the population has been exploited due to overfishing

scholarly journals BIOLOGY AND POPULATION DYNAMICS OF BANANA SHRIMP (Penaeus merguiensis) IN THE TARAKAN WATERS, EAST BORNEO

2013 ◽  
Vol 19 (2) ◽  
pp. 99 ◽  
Author(s):  
Duranta D. Kembaren ◽  
Ali Suman
Keyword(s):  
Population Dynamics ◽  
Mortality Rate ◽  
Total Mortality ◽  
Population Data ◽  
Fishing Effort ◽  
Growth Coefficient ◽  
Exploitation Rate ◽  
First Maturity ◽  
Dynamic Population ◽  
Penaeus Merguiensis

Study of biology and population dynamic of banana shrimp (<em>Penaeus merguiensis</em>) in Tarakan waters, East Borneo was carried out from January to November 2012. The aim of this research was to identify the biological aspects and population dynamics of banana shrimp. For estimating dynamic population, data were analysed using FiSAT II. The result showed that length at first capture (Lc) of banana shrimp by mini trawl (pukat hela) was 35 mm and the size at first maturity (Lm) was 33,86 mm in carapace length. Spawning occured all year around and reached it’s peak in March. The growth coefficient (K) of banana shrimp was 1,45/year with carapace asymptotic length (CL”) of 80 mm. Total mortality rate (Z) and natural mortality rate (M) were 4,85/year and 1,76/year. While fishing mortality rate (F) and exploitation rate (E) were 3,09/year and 0,64, respectively. The exploitation rate of banana shrimp in Tarakan waters tended to be overexploited so that it needed to be managed wisely and carefully by reducing the fishing effort and fishing season especially on spawning season. The recruitment peak of banana shrimp occured in May.

Description of a new species of clupeid fish, Amblygaster indiana (Clupeiformes: Clupeidae), off Eraviputhenthurai, west coast of India

Zootaxa ◽  
2017 ◽  
Vol 4247 (4) ◽  
pp. 461
Author(s):  
ANTHONIPILLAI AROCKIA MARY ◽  
THNGAVELU BALASUBRAMANIAN ◽  
SHANKER SELVARAJU ◽  
ANTHONIPILLAI SHINY
Keyword(s):  
New Species ◽  
West Coast ◽  
Coastal Waters ◽  
Coastal Zones ◽  
West Coast Of India ◽  
South West ◽  
South West Coast ◽  
Left And Right ◽  
A New Species ◽  
Deep Body

A new species, Amblygaster indiana sp. nov., is described from 12 specimens collected from fish landing centers and fish markets at Eraviputhenthurai, west coast of India. The new species can be differentiated from all other species of Amblygaster by its larger size and very deep body, 8 circular-shaped pre-pelvic scutes, different gill rakers counts, large eyes, 40 lateral scales, and peculiar gap between the left and right frontoparietal striae on the top of the head. The new species has been seasonally captured with A. sirm in Eraviputhenthurai and also other coastal waters of the south west coast of India. The proportions of A. indiana sp. nov. and A. sirm in fish catches are approximately 1 to 20. Gillnets and shore seines are used to catch Amblygaster spp. along the Eraviputhenthurai coast and along the coastal zones of south west coasts of India. 

scholarly journals POPULATION DYNAMICS OF TUNA (EUTHYNNUS AFFINIS, CANTOR 1849) IN WESTERN WATERS OF SOUTH SULAWESI

2020 ◽  
Vol 8 (8) ◽  
pp. 164-172
Author(s):  
Budiman Yunus ◽  
Suwarni ◽  
Basse Siang Parawansa
Keyword(s):  
Population Dynamics ◽  
Mortality Rate ◽  
Age Groups ◽  
Total Mortality ◽  
Assessment Tools ◽  
Natural Mortality ◽  
Age Group ◽  
Fishing Mortality ◽  
Growth Coefficient ◽  
South Sulawesi

This study aims to determine the population dynamics of tuna including age group, growth, mortality, exploitation rate and yield per recruitment. It was conducted from June to August in West Waters of South Sulawesi. By method of age group using Bhattacharya method with FAO-ICLARM Fish Stock Assessment Tools II (FISAT II) program, growth using Von Bertalanffy’s equation, natural mortality (M) using Pauly’s empirical equation, total mortality (Z) using Beverton and Holt’s equations, fishing mortality (F) by the formula Z = F + M, exploitation (E) using Baverton and Holt’s equations and yield per recruitment (Y/R’) using Baverton and Holt’s equations. The results of research of tuna observed were 737 includes 355 male tunas and 382 female tunas. The estimation of total length ranging from 215 mm to 429 mm. Male tunas are classified into 4 (four) of age groups with a length of 236.67, 272.8, 326.04 and 375.53 mm, respectively. Asymptote length (L∞) = 455.00 mm, growth coefficient (K) = 0.33 and theoretical age (t0) of -0.2377 per year. Total mortality rate (Z) = 1.12 per year. Natural mortality (M) = 0.41 per year, fishing mortality (F) = 0.71, exploitation (E) = 0.63 and yield per recruitment (Y/R’) = 0.0691, while male tunas are classified into 5 (five) of age groups with a length of 235.73, 272.86, 326.89, 360.89 and 408.89 mm, respectively. Asymptote length (L∞) = 453.50 mm, growth coefficient (K) = 0.42 and theoretical age (t0) of -0.1853 per year. Total mortality rate (Z) = 1.35 per year. Natural mortality (M) = 0.48 per year, fishing mortality (F) = 0.87, exploitation (E) = 0.64 and yield per recruitment (Y/R’) = 0.0784. Thus, it can be concluded that tuna in West Waters of South Sulawesi have declined and thought occur overfishing.

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