scholarly journals Population dynamics of eastern little tuna (Euthynnus affinis) in Ternate Waters

2021 ◽  
Vol 890 (1) ◽  
pp. 012053
Author(s):  
U Tangke ◽  
R Laisouw ◽  
A Talib ◽  
Azis Husen ◽  
R Kota ◽  
...  

Abstract Eastern little tuna production still depends on stocks from nature, so it is feared that if production continues to increase it will threaten the sustainability of tuna resources, therefore for the sake of sustainable management information is needed on population parameters so that research is carried out from January to April 2021 with the aim of assessing the dynamics of the population of these resources. The data collection procedure was carried out by measuring the total length of the fish caught per fishing trip for 4 months using a meter with a unit (centimeter) cm and an accuracy of 1 mm. The results of the research showed that tuna in the southern waters of Ternate Island had stable growth parameters including maximum length (L∞) 68.25 cm with a growth coefficient (K) of 0.25 per month, t0 -0.20, with total mortality, natural and fishing values respectively. respectively are 0.64, 0.43, 0.21 and the level of exploitation is 0.33 where this value indicates that the rate of exploitation is smaller so it is necessary to increase fishing effort until the optimum value reaches 0.38.

2020 ◽  
Vol 19 (1) ◽  
pp. 51-57
Author(s):  
Stephen O. Ajagbe ◽  
Folashade. F. Ojo-fakuade

The structure of a fish population is determined by the equilibrium between growth, recruitment and total mortality. But, there is paucity of information on the growth and mortality of Mormyrus rume in Nigeria. Therefore this study is needful to determine its population parameters, with a view of evolving management strategies for its sustainable exploitation. Estimates of population parameters of Mormyrus rume were obtained from length-frequency data of 836 individuals collected monthly for a period of 24 months from January 2017 to December 2018. The estimated growth parameters were: asymptotic length (L∞) was 100.8cm; growth coefficient (K) was 0.62/year; growth performance (Ɵ) was 3.8; length at maturity (Lm) was 52.57cm; reproductive load (Lm/L∞) was 0.52 and optimum length (Lopt) was 65.10cm. Likewise, natural, fishing and total mortalities were 0.93, 1.46 and 2.39 respectively. The values of exploitation rate (0.61) and ratio of total mortality and growth coefficient (3.85) showed that Mormyrus rume is most exploited in Ikere-gorge. Therefore, appropriate fishing regulations should be enforced to regulate fishing gears and mesh size that will fish Mormyrus rume at sustainable level. Keywords: Recruitment, mortality, growth, exploitation, length


2017 ◽  
Vol 9 (1) ◽  
pp. 11
Author(s):  
Tirtadanu Tirtadanu ◽  
Suprapto Suprapto ◽  
Ali Suman

Udang jinga (Metapenaeus affinis H. Milne Edwards, 1837) merupakan salah satu jenis udang ekonomis penting yang diusahakan di perairan Kotabaru dan saat ini produksinya cenderung mengalami penurunan. Salah satu data dan informasi yang diperlukan dalam mengkaji tingkat pemanfaatan dan dasar pengelolaannya adalah aspek biologi dan parameter populasi. Penelitian ini bertujuan mengkaji aspek biologi dan parameter populasi udang jinga sebagai bahan kebijakan pengelolaan perikanan udang di perairan Kotabaru, Kalimantan Selatan. Penelitian dilakukan pada bulan Januari – November 2016 di perairan Kotabaru. Parameter pertumbuhan diestimasi berdasarkan pergeseran modus struktur ukuran panjang dengan metode ELEFAN I. Hasil penelitian menunjukkan rata-rata ukuran udang jinga (M. affinis) betina yang tertangkap adalah 23,6 ± 3,45 mmCL dengan modus ukuran 24 mmCL dan rata-rata ukuran udang jantan adalah 20,7 ± 2,9 mm dengan modus ukuran 18 mmCL. Nisbah kelamin udang jinga jantan dan betina adalah 1 : 2,5. Musim pemijahan udang jinga diduga berlangsung sepanjang tahun dan puncak pada bulan Maret. Ukuran rata-rata pertama kali tertangkap (Lc) udang lebih kecil dari ukuran rata-rata pertama kali matang gonad (Lm) (21,7 < 28,5 mm CL) sehingga sebagian besar udang tertangkap berukuran kecil dan belum memijah. Persamaan pertumbuhan udang jinga jantan  CL(t)=35,95(1-e-2.02(t+0,31) dan udang jinga betina CL(t)= 38,3(1-e-1,92(t+0,29)). Tingkat pemanfaatan udang (E) menunjukkan lebih tangkap (overfishing) yakni 0,70/tahun pada jantan dan 0,73/tahun pada betina. Dengan demikian disarankan untuk melakukan pengurangan upaya penangkapan sebesar 40% dan penutupan musim penangkapan di bulan Maret.The jinga shrimp (Metapenaeus affinis H. Milne Edwards, 1837) was one of important commodity that was exploited in Kotabaru Waters, yet the production tend to be declined recently. The data and information on biological aspects and population parameters are needed to investigate the exploitation level and the basis of management measures. This research aims to investigate the biological aspects and population parameters of jinga shrimp Kotabaru waters, South of Kalimantan. This research was conducted on January – November 2016. The growth parameters were estimated as movement of length frequency mode by ELEFAN I method. The results showed that the mean size of female jinga shrimp (M. affinis) was 23,6 ± 3,45 mm CL and the mode was 24 mmCL. While, the mean size of male jinga shrimp was 20,7 ± 2.9 mm CL and the mode was 18 mmCL. The sex ratio of male and female shrimp was 1 : 2,5 . Spawning season of jinga shrimp was estimated throughout the year and the peak was in March. The length at first captured (Lc) was shorter than length at first matured (Lm) (21,7 < 28,5 mm CL). That means most of the catches was immature. The growth function of male and female jinga shrimp were and, CL(t)=35,95(1-e-2.02(t+0,31) respectively and CL(t)= 38,3(1-e-1,92(t+0,29)). The exploitation rate (E) of male and female shrimp fishing were  0,70/year 0,73/year, respectively. The reduction of fishing effort needed by 40% of the actual combined with the temporal fishing closure March.


2019 ◽  
Vol 32 ◽  
pp. 9
Author(s):  
Theparambil Mohamed Najmudeen ◽  
Pallangattu Kochukandan Seetha ◽  
Payiyappanal Ulahannan Zacharia

The brushtooth lizardfish Saurida undosquamis (Richardson, 1848) is a high trophic level benthic predator and is one among the most exploited demersal finfish species from eastern Arabian Sea by Indian trawlers. However, in recent years, the landings of many top predator fishes including S. undosquamis showed a declining trend resulting in a steady decline in the mean trophic levels of the fishes caught commercially in the region. We investigated the growth, mortality and stock dynamics of S. undosquamis harvested by mechanised trawls in the southeastern Arabian Sea, using length-based methods for the data collected during 2012–2016. Besides, Bayesian state-space implementation of the Schaefer model (BSM) and catch-based MSY (CMSY) estimation were also made using the data for the period 1985–2016. Total length of the fish ranged from 5.5 to 34.5 cm with average annual mean length of 22.0 cm during 2012–2016. The growth parameters L∞ and K were 37.3 cm and 0.41 year−1, respectively. The natural, fishing and total mortality coefficients were 0.92, 2.58 and 3.5, respectively and exploitation ratio was 0.82. The length at first maturity was estimated at 21.4 cm for females. The mean size in the catch is lower than the optimum length for exploitation. Fisheries reference points (MSY, Fmsy, Bmsy) as well as relative stock size (B/Bmsy) and exploitation (F/Fmsy) estimated from catch data and broad priors for resilience (r), implies an exploitation of 30% below Bmsy level. Results from the length-based Thompson and Bell prediction model indicates that reducing the present level of fishing effort by 40% would lead to a harvest of the species at a sustainable level. As “fishing down food web” is reported in recent years from eastern Arabian Sea, the exploitation of top predators need to be maintained at sustainable levels to prevent ecosystem changes along the region.


2019 ◽  
Vol 25 (1) ◽  
pp. 19
Author(s):  
Ali Suman ◽  
Prihatiningsih Prihatiningsih ◽  
Pratiwi Lestari ◽  
Andina Ramadhani Putri Pane

Study on the population dynamic of endeavour shrimp (Metapenaus ensis) was conducted in Binuangeun waters based on data collected during period of survey, January to November 2016. The purpose of the study was to identify population parameters of the endeavour shrimp. Result showed that the endeavor shrimp growth pattern in Binuangeun waters was negative allometric and sex ratio of males and females was 1.0 : 2.7. The chi square test indicated that comparison of male and female of the endeavour shrimp was significantly different. It mean that there was imbalance in number between males and females. The length at first capture (Lc) of endeavour shrimp was 28.9 mm (carapace length),smaller than the length at first maturity (Lm) at 37.7 mm (carapace length). The growth parameter of endeavour shrimp was 1.33/year with maximum carapace length (Loo) of 51.45 mm. Instantenous total mortality (Z) and natural mortality (M) were 7.74/year and 1.88/year, respectively. While fishing mortality (F) and exploitation rate (E) respectively were 5.86/year and 0.76/year. The exploitation rate of endeavour shrimp in Binuangeun and adjacent waters was high. It was, therefore, recommended that fishing effort of the endeavour shrimp in that waters should be reduced about 52 % in the next year.


Author(s):  
Wu Bin Wang Haihua ◽  
Fu Huiyun Zhang Yanping

A study was conducted to investigate the growth parameters, mortality and recruitment pattern of Odontobutis potamophila collected in the Gaosha river fish landing site, west part of Wuyuan County (Latitude: 29° 14' 29" N, Longitude: 117° 45' 49" E). O.potamophila were collected from November, 2013 to October, 2014. Growth parameters, asymptotic length (L) = 192mm and growth coefficient (k) = 0.22 year-1. Growth performance index(Ø’) =3.91, total mortality (Z) = 0.72 year-1, natural mortality (M) = 0.32 year-1, fishing mortality (F) = 0.40 year-1 and exploitation rate (E) = 0.55year-1.The estimated exploitation rate (E) has slightly exceeded the optimum value of E indicating this species was sustainable exploitation in the study area. The exploitation ratios were computed as Emax= 0.61, E10= 0.52, E50= 0.34. The length at first capture at 50%, (Lc) was 77 mm. The recruitment pattern of the species was found continuous all-round the year with one peak. The observation of the annual recruitment of O.potamophila found to occur from May to July. Steady biomass also increased with length class until 121-125 mm, and the total steady state biomass was found to be 2240 kg.


2018 ◽  
Vol 9 (3) ◽  
pp. 163
Author(s):  
Raymon Rahmanov Zedta ◽  
Prawira Atmaja Rintar PT ◽  
Dian Novianto Novianto

Penelitian ini bertujuan untuk mengkaji parameter populasi ikan cakalang (Katsuwonus pelamis) yang tertangkap pukat cincin di WPP-572 Samudra Hindia Barat Sumatera dan WPP-573 Selatan Jawa. Hasil penelitian ini diharapkan dapat digunakan sebagai masukan dalam penentuan pengelolaan perikanan sehingga stok ikan cakalang dapat dimanfaatkan secara berkelanjutan. Ikan contoh dikumpulkan melalui program enumerasi tahun 2016 (Januari-Desember). Sampling acak dilaksanakan di empat pelabuhan, yaitu PPS Lampulo (Aceh), PPN Sibolga (Sumatra Utara), PPP Tamperan (Pacitan) dan IPP Pondokdadap (Malang). Jumlah ikan contoh diperoleh sebanyak 14.894 ekor. Serial data fekuensi panjang bulanan diolah menggunakan program FiSAT II untuk menduga parameter pertumbuhan, mortalitas dan tingkat eksploitasi. Hasil penelitian menunjukkan ikan cakalang yang tertangkap di WPP-572 memiliki panjang asimtotik (L)73,5 cmFL, K sebesar 0.22/tahun dan to sebesar -0,59 tahun. Parameter populasi di WPP-573 berturut-turut L”=67,20 cmFL, K=0,27/tahun, dan to=-0,50 tahun. Nilai mortalitas alami (M) ikan cakalang di WPP 572 sebesar 0,49/tahun, mortalitas total (Z) 0,70/tahun, dan kematian akibat penangkapan (F) adalah 0,21/tahun. Ikan cakalang yang tertangkap di WPP 573 menunjukkan nilai (E) sebesar 0,59/tahun, nilai Z 1,02/tahun, dan nilai F sebesar 0,43/tahun. Dugaan tingkat eksploitasi ikan cakalang di WPP 572 dan 573 masing-masing 0,3/tahun dan 0,42/tahun atau belum berada pada tahap optimal.This study aimed to assess the population parameters of skipjack tuna (Katsuwonus pelamis) that caught by purse seine in the Indonesian FMA (Fisheries Management Area) 572 Indian Ocean West Sumatera and FMA 573 South Java. The outcomes of this research can hopefully be used as inputs for fisheries management, in order the stock of skipjack tuna can be utilized sustainably. Fish sample were collected through the program enumeration of Research Institute for Tuna Fisheries (RITF) during the year 2016 (Januari-Desember). Using random sampling method at four fishing ports, namely PPS Lampulo (Aceh), PPN Sibolga (North Sumatra), PPP Tamperan (Pacitan), and IPP Pondokdadap (Malang). The total number of fish samples was 14.894 fish. Monthly length frequency data processed using FiSAT II program to estimate the growth parameters, mortality, and exploitation. The analysis results showed that skipjack tuna caught in FMA 572 has asymtotic length value (L) at 73.5 cmFL, K value 0.22/year, and to at -0.59 year; while in FMA 573 population parameters values respectively 67.20 cmFL, 0.27/year, and -0.50 year. The value of natural mortality (M) skipjack in FMA 572 is 0.49/year, total mortality (Z) 0.70/year, and fishing mortality (F) 0.21/year. Skipjack tuna that caught in FMA 573 showed value of M 0.59/year, Z value 1.02/year, and F value 0.43/year. The estimated values of exploitation levels of skipjack in FMA 572 and 573 were 0.3/year and 0.42/year respectively.


2018 ◽  
Vol 9 (3) ◽  
pp. 185
Author(s):  
Helman Nur Yusuf ◽  
Ali Suman ◽  
Thomas Hidayat ◽  
Anthony Sisco Panggabean

Lobster bambu (Panulirus versicolor) merupakan komoditas perikanan penting yang telah diekspolitasi di perairan Simeulue. Peningkatan permintaan dan pengusahaan lobster menyebabkan tekanan penangkapan terhadap populasi lobster semakin intensif dan tidak terkendali. Untuk itu  diperlukan informasi tentang biologi reproduksi dan parameter populasi lobster dalam rangka pengelolaan sumberdaya lobster yang berkelanjutan. Penelitian dilaksanakan pada Mei sampai dengan Desember 2015 diperairan Simeulue dengan tujuan untuk mengestimasi parameter populasi lobster bambu. Pengamatan dan pengukuran lobster dilakukan di tempat pengumpul lobster dengan sistem sampling acak (random sampling). Analisis data parameter populasi menggunakan software FiSAT (Stock Assessement Tools). Dari hasil penelitian diperoleh bahwa kondisi lobster bambu jantan dan betina tidak seimbang (1 : 1,5),  pola pertumbuhan bersifat alometrik negatif dengan nilai b sebesar 2,924 dan rata-rata pertama kali tertangkap (Lc) = 86 mmCL. Laju pertumbuhan (K) = 0,320 per tahun dan panjang karapas asimtotik (CL) 149,1 mm. Laju mortalitas alami (M) = 0,99 per tahun, laju kematian akibat penangkapan (F) sebesar 0,84 per tahun dan laju kematian total (Z) sebesar 1,83 per tahun. Tingkat eksploitasi (E) sebesar 0,46 atau pemanfaatan sumberdaya lobster bambu belum optimum. Penambahan baru dalam populasi berlangsung sepanjang tahun dan mencapai puncaknya pada Juni dan Juli bersamaan dengan musim timur. Untuk itu perlu adanya regulasi pemerintah dalam pengelolaan perikanan lobster yang berkelanjutan dengan menerapkan close season lobster pada puncak musim pemijahan.The painted green/bamboo lobster (Panulirus versicolor) is an important fish commodities that have been exploited in the waters of Simeulue. Increased utilization and uncontrolled exploitation of lobster causing pressure on the lobster population. For this reason, there is a need for information about the parameters of the lobster population in the management for the sustainability of lobster resource. The experiment was conducted in May to December 2015 Simeulue waters for the purpose of estimating the population parameters lobster green. Sampel collected randomly in the lobster landing site. Analysis of the data using FiSAT II software (FAO-ICLARM Stock Assessement Tools). The results obtained unbalanced condition of green lobster (1:1.5), the growth pattern is allometrically negative with value b of 2,924, length at fish first caught (Lc) = 86 mm CL. The lobster growth rate (K) = 0,320 per year and asymptotic carapace length (CL) 149.10 mm. The rate of natural mortality (M) = 0.99 per year, the mortality rate due to the arrest of (F) of 0.84 per year and total mortality rate (Z) of 1.83 per year. The rate of exploitation (E) 0,46 or green lobster resource was not optimum. Recruitment occur throughout the year with peak recruitment in June and July of the southeast monsoon. A government regulation is needed for the sustainable management of lobster resources by applying a close season during the peak spawning peri.


2020 ◽  
Vol 12 (1) ◽  
pp. 11
Author(s):  
Umi Chodrijah ◽  
Ria Faizah ◽  
Tirta Danu

Udang tiger (Penaeus monodon Fabricius 1798) di Tarakan merupakan salah satu komoditas ekspor dan sudah dimanfaatkan cukup lama serta memiliki permintaan dan nilai ekonomis yang tinggi. Penelitian dinamika populasi dan status pemanfaatan udang tiger di perairan Tarakan dan sekitarnya dilakukan untuk mengevaluasi status stok sumberdaya udang agar pengelolaannya dapat berkelanjutan. Penelitian ini dilakukan pada bulan Januari-November 2016 dengan metode survey. Status pemanfaatan diduga berdasarkan laju eksploitasi dan estimasi rasio pemijahan berbasis data panjang (LB-SPR). Hasil pengamatan menunjukkan udang tiger memiliki panjang karapas asimptotik (CL∞) sebesar 65,45 mm, laju pertumbuhan (K) sebesar 1,55 /tahun dan nilai t0 sebesar -0,20/tahun sehingga diperoleh persamaan pertumbuhan Von Bertalanffy CLt = 65,45(1 – e-1,55(t+-0,20)). Laju mortalitas total (Z) sebesar 6,56/ tahun, mortalitas alami (M) sebesar 1,95/tahun, mortalitas penangkapan (F) sebesar 4,62/tahun dan tingkat pemanfaatan (E) sebesar 0,70 /tahun. Tingkat pemanfaatan udang tiger di perairan Tarakan lebih besar dari tingkat pemanfaatan optimal sehingga disarankan untuk menurunkan upaya sebesar 40% dari upaya saat ini.Tiger prawn (Penaeus monodon Fabricius 1798) was one of the export commodity and had been exploited for longtime ago so it was necessary to study about its population parameters and exploitation status for its sustainable management. This research aimed to study about the population parameters and exploitation status of tiger prawn. The research were carried out from January to November 2016 using survey method and the enumeration programme. The growth parameters were based on the Modal Progression Analysis. Exploitation status was estimated based on length based spawning potential ratio (LB-SPR). The results showed that the asymptotic length (CL∞) was 65.45 mm, the growth rate (K) was 1.55 /year and = t0 was -0,20/year so Von Bertalanffy Growth Model was CLt = 65.45(1 - e -1.55(t+-0.20)). Total mortality (Z) was 6.56/years, natural mortality was 1.95/years and fishing mortality was 4.62/years and the highest recruitment of tiger prawns occured in May. The exploitation rate (E) was 0,70/years. The exploitation rate now is higher then the optimal level so it is recommended to reduce 40% of the current efforts.


2017 ◽  
Vol 9 (2) ◽  
pp. 85
Author(s):  
Umi Chodrijah ◽  
Ali Suman

Tingkat eksploitasi udang putih (Penaeus merguiensis) sangat intensif. Hal ini terindikasi dengan hasil tangkapan udang di WPP-NRI 716 selama 9 tahun terakhir meningkat. Tujuan penelitian ini untuk mengkaji beberapa parameter populasi dan aspek biologi udang putih di perairan Tarakan. Data panjang karapas dan tingkat kematangan gonad udang putih dikumpulkan dari tempat pendaratan udang di Selumit Pantai, Tarakan, Kalimantan Utara pada Januari sampai dengan November 2016. Pendugaan parameter populasi dengan aplikasi model analisis menggunakan program ELEFAN 1. Hasil penelitian menunjukkan rata-rata ukuran udang putih pertama kali tertangkap (Lc) pada panjang karapas 32,51 mm dan rata-rata ukuran pertama kali matang gonad 33,58 mm. Puncak musim pemijahan terjadi pada Maret dan Agustus. Laju pertumbuhan (K) sebesar 1,33 per tahun (betina) dan 1,55 per tahun (jantan). Laju kematian total (Z) sebesar 7,5 per tahun (betina) dan 8,85 per tahun (jantan), laju kematian alamiah (M) sebesar 1,82 per tahun (betina) dan 2,16 per tahun (jantan) serta laju kematian akibat penangkapan (F) sebesar 5,68 per tahun (betina) dan 6,69 per tahun (jantan). Laju pengusahaan (E) udang putih di perairan Tarakan adalah sebesar 0,76 per tahun. Hal ini menunjukkan tingkat pemanfaatan udang putih telah mengalami lebih tangkap (overfishing). Kondisi ini menggambarkan perlunya dilakukan pengurangan upaya sekitar 52 %.  The banana prawn (Penaeus merguiensis) have been exploited intensively. For instance, within nine years the number of shrimp production in FMA 716 increased dramatically. This research aims to identify the some population parameters of banana prawn in the Tarakan waters. This research was carried out from January to November 2016. Data were analyzed using the analytical model application with ELEFAN I. The result showed that the length at first capture (Lc) of banana prawn was 32,51 mmCL and the length at first maturity (Lm) was 33,58 mm CL. The peak season of spawning period was indicated on March and August. The growth rate (K) was 1,33 /year (female) and 1.55/year (male). Total mortality rate (Z) was 7.5/year (female) and 8,85/year (male), natural mortality rate (M) rate was 1.82/year (female) and 2.16/year (male) and fishing mortality rate ( F) were 5.68/ year (female) and 6.69/year (male). The exploitation rate (E) of banana prawn in the Tarakan waters was 0.76 per year. Therefore, level of existing fishing effort of the banana prawn should reduced about 52 % in the next year.


2013 ◽  
Vol 19 (2) ◽  
pp. 99 ◽  
Author(s):  
Duranta D. Kembaren ◽  
Ali Suman

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.


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