scholarly journals Estimates of Length-Based Estimates of length-based population parameters of the skipjack tuna, Katsuwonus pelamis (Linnaeus, 1758) in the Andaman watersPopulation Parameters of the Skipjack Tuna, Katsuwonus pelamis (Linnaeus, 1758) in the Andaman waters

2017 ◽  
Vol 5 (2) ◽  
Author(s):  
Pradeep Hosahalli Divakar ◽  
Swapnil Shivdas Shirke ◽  
Annada Bhusan Kar

The exploitation level of skipjack tuna, Katsuwonus pelamis in Andaman waters is meagre compared to its total landings in India.  As the population parameters of this species has not been attempted in these waters, an attempt has been made in this paper to estimate the population parameters of K. pelamis based on the length frequency data collected from local fishing boats operating from Junglighat Fishing Harbour, Port Blair, Andaman Islands from January to December 2014. A total of 704 specimens ranging from 16.5 to 71.0 cm fork length were taken for analysis. The parameters L∞, K and t0 were 74.55 cm, 0.59/year and –0.21 respectively. The von Bertalanffy growth equation for K. pelamis is Lt = 74.6[1 – e–0.59(t+0.214255)]. The recruitment pattern was unimodal. The recruitment period was from July – October. The longevity of the species was calculated as 4.9 years. After 1st, 2nd, 3rd and 4th year the length attained by the species is 38.1, 54.4, 63.4 and 68.3 cm respectively. The mortality parameters were Z = 2.07, M = 0.93, F = 1.14 and exploitation ratio was 0.55. The virtual population analysis (VPA) for K. pelamis indicated that fishing mortality starts at 41–50 cm class interval and it continues henceforth and was maximum at 61–70 cm and decreased thereafter.

2017 ◽  
Vol 9 (2) ◽  
pp. 113
Author(s):  
Thomas Hidayat ◽  
Tegoeh Noegroho ◽  
Karsono Wagiyo

Ikan cakalang (Katsuwonus pelamis Linnaeus, 1758) merupakan salah satu sumberdaya ikan pelagis besar yang mempunyai nilai ekonomis penting. Informasi mengenai struktur ukuran dan beberapa parameter populasinya masih sangat terbatas khususnya di perairan Indonesia timur. Penelitian ini dilakukan di Morotai, Biak dan Jayapura dari Januari sampai Desember 2013. Tujuan penelitian ini adalah untuk menganalisis ukuran ikan yang tertangkap dan menganalisis parameter populasi meliputi laju pertumbuhan, mortalitas dan tingkat eksploitasi. Estimasi parameter pertumbuhan, mortalitas dan laju eksploitasi dihitung menggunakan program FiSAT (FAO-ICLARM Stock Assessement Tools). Ukuran ikan cakalang hasil tangkapan pancing tonda dan pancing ulur berkisar antara 15 – 94 cmFL (Fork Length), dengan modus antara 40-45 cmFL. Ukuran pertama kali tertangkap sebesar 40,1 cmFL dan kebanyakan adalah ukuran ikan yang sedang memijah. Hasil analisis menggunakan FiSAT II diperoleh laju pertumbuhan (K) sebesar 0,41/tahun, panjang asimptotik (L) 101,85 cmFL. Laju kematian alami (M) 0,6 / tahun, laju kematian karena penangkapan (F) 0,62 /tahun dan laju mortalitas total (Z) 1,22 /tahun. Tingkat eksploitasi ikan cakalang hampir fully exploited (E= 0,46). Disarankan tidak perlu ada penambahan upaya penangkapan atau status quo untuk menjaga agar sumberdaya ikan cakalang tetap terjaga kelestariannya. Skipjack tuna (Katsuwonus pelamis Linnaeus, 1758) is one of the large pelagic fish resources which have high economic value. Information on the size structure and population parameters is still limited especially in the waters of eastern Indonesia. The Research was conducted from January to December 2013 at Morotai, Biak and Jayapura. The aim of this study was to analyze the size of the fish caught and some of population parameters such as the growth rate, mortality rates, and exploitation rate. Estimated of growth parameters, mortality and exploitation rate using the program FiSAT (FAO-ICLARM Stock Assessement Tools). The size of skipjack tuna caught by troll line and handline in between 15-94 cmFL, with a mode of 40-45 cmFL. The Length at first capture was 40.1 cmFL, most of them had condition of spawning. By using program FiSAT II analysis resulted that growth rate (K) of skipjack tuna was 0.41/year, with length asimptotik (L) reaches 101.85 cmFL. The natural mortality rate (M) was 0.6 / year. The fishing mortality rate (F) was 0.62 / year and total mortality rate (Z) was 1.22 / year. The exploitation rate of skipjack tuna was nearly fully exploited (E = 0.46). It was recommended the exploitation rate of this fish should be no additional effort (status quo) to keep sustainability of the skipjack tuna resource.


2016 ◽  
Vol 74 (4) ◽  
pp. 141-148 ◽  
Author(s):  
Semra Saygin ◽  
Savas Yilmaz ◽  
Okan Yazicioglu ◽  
Nazmi Polat

AbstractThe aim of this study was to determine the growth features of European perch (Perca fluviatilis L., 1758) inhabiting Lake Ladik. A total of 858 individuals were caught. The total length and weight ranged from 8.2 to 27.5 cm and from 7.16 to 365.20 g, respectively. The age of the females ranged between 1 and 7 years and the age of the males ranged from 1 to 5 years. The female to male ratio was 1:0.19. The von Bertalanffy growth equation parameters were determined as L∞=41.27 cm, W∞=1251.40 g, K=0.10 (year−1), t0 (year)=−1.98 for all samples. Length-weight relationship was calculated as W=0.0047TL3.358 for all specimens. Length-length relationships (total length-standard length, total length-fork length, standard length-fork length) were highly significant (r2>0.98). The mean condition factor value was obtained as 1.28 for all fish. Condition factor showed statistically significant increase according to length classes.


Author(s):  
Irham . ◽  
Amirul Karman ◽  
Kusdi Hi Iksan

ABSTRACTTernate Island lies in a strategic location as it is situated in the middle of  the main fishing ground for skipjack (Katsuwonus pelamis) fishing using pole and line (huhate) and fish aggregating devices (FADs). As typical pelagic fish, skipjack that is gathered near the water surface is the younger fish, likewise the ones which are caught around FADs. Therefore, this fishing method has caused serious problem due to the domination of young fish and increasing bycatch and discard. The objective of this research is to analyze the size structure of the fork length, appropriate size for catching, catch composition, bycatch and discard level. Pole and line catch samples were collected in 3 months fromMay to July 2018. The results show that in average, skipjack tuna caught in the study location was undersize. The total catch is predominantly targeted fish which has a higher economic value compared to bycatch and discarded fish. Even though bycatch in the pole and line fisheries are low, reduction efforts are still required. which can be done by sorting bycatch and unwanted fish then discard it into the sea when the fish is still alive.Keywords: biology, pole and line, sustainability status, Ternate City ABSTRAKPosisi Pulau Ternate sangat strategis karena berada di tengah perairan yang menjadi daerah operasi penangkapan cakalang (Katsuwonus pelamis) dengan alat tangkap huhate (pole and line) yang dibantu dengan penggunaan rumpon. Sebagaimana ikan pelagis lainnya,  ikan-ikan cakalang yang berkumpul di lapisan permukaan air cenderung tergolong ikan-ikan muda. Oleh karena itu, cakalang yang tertangkap di sekitar rumpon juga cenderung ikan-ikan yang masih muda. Fenomena ini menyebabkan munculnya sebuah masalah besar, yaitu dominasi ikan-ikan muda, selain itu juga sering tertangkap ikan yang bukan target tangkap yang terdiri dari bycatch dan discards. Tujuan dari penelitian ini adalah menganalisis struktur ukuran panjang cagak dan ukuran cakalang layak tangkap, komposisi hasil tangkapan, persentase bycatch dan discards. Sampel hasil tangkapan huhate dikumpulkan selama 3 bulan (Mei sampai Juli 2018). Hasil penelitian menunjukkan bahwa rataan cakalang di lokasi penelitian didominasi ukuran belum layak tangkap. Total hasil tangkapan didominasi ikan target, sementara itu bycatch yang tertangkap memiliki nilai ekonomis yang baik dan tidak ditemukan discards. Walaupun bycatch pada perikanan huhate rendah namun usaha-usaha untuk meminimumkan tetap perlu dilakukan. Salah satu usaha yang bisa dilakukan adalah menyortir hasil tangkapan, ada apabila ada ikan yang akan dibuang ke laut, dilakukan dalam keadaan masih hidup.Kata Kunci: Biologi, huhate (pole and line), status keberlanjutan, Kota Ternate


Author(s):  
Michael L Burton ◽  
Jennifer C Potts ◽  
Ariel J Poholek ◽  
Jordan Page

Sectioned otoliths were used to age littlehead porgy Calamus proridens (n = 737) from southeastern Florida recreational fisheries. Otolith sections contained easily identifiable annuli and were reliable structures for aging littlehead porgy up to 11 yrs. Opaque zones were deposited from March to June (peaking in April). Littlehead porgy ranged from 1 to 11 yrs and 220 to 385 mm total length (TL). Body size relationships were TL = 1.09 FL + 16.06 (n = 3474, r2 = 0.95), FL = 0.87 TL – 1.15 (n = 3474, r2 = 0.95), W = 4.76 × 10 −5 TL2.80 (n = 6722, r2 = 0.86), and W = 1.2 × 10−4 FL2.71 (n = 3474, r2 = 0.90), where W is total weight (g) and FL is fork length (mm). Growth was not significantly different between two discrete geographic regions of Florida, and the von Bertalanffy growth equation was Lt = 335 (1 − e−0.41 (t + 2.13)) for all areas combined. The point estimate of natural mortality was M = 0.38, while age-specific estimates of M ranged from 0.60 to 0.41 yrs−1 for ages 1–11. Littlehead porgy were fully recruited to the headboat fishery by age-3 and catch curve analysis resulted in an estimate of total mortality Z = 1.08 for ages 3–7+. This study reports first estimates of life history parameters for littlehead porgy from Atlantic waters of the southeastern United States.


1995 ◽  
Vol 46 (3) ◽  
pp. 591 ◽  
Author(s):  
FE Wells ◽  
P Mulvay

On the southern coast of Western Australia, proportionately more reproductive specimens of greenlip abalone, H. laevigata, were of legal size in 'good' fishing areas than in 'bad' fishing areas. Sex ratios were usually 1:1. Maturation of the gonads began at a size of 70-90 mm shell length (SL) and by 100-110 mm SL all animals were reproductively mature. Size-specific fecundities were not statistically different among the four good fishing areas examined, nor were they between the two bad fishing areas, but size-specific fecundity was greater in good than in bad fishing areas. Spawning begins as soon as the animals are mature; there is no gap between apparent histological maturity and actual spawning. Gonads are quiescent in the first part of the calendar year. Development is rapid in August and September, when animals begin to reach ripe condition. A maximum proportion of ripe animals occurs in October and November, followed by spawning in December. There was no difference between growth rates of males and females in either the good or the bad fishing areas. The von Bertalanffy growth equation disclosed no difference in growth between good and bad fishing areas, but close inspection of the data suggested that slower growth did occur in the bad fishing areas. The abalone reach reproductive maturity at an age of 2.5 to 3 years and the legal size of 140 mm SL at 5 to 6 years.


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.


2015 ◽  
Vol 7 (2) ◽  
pp. 87
Author(s):  
Irwan Jatmiko ◽  
Hety Hartaty ◽  
Andi Bahtiar

Cakalang (Katsuwonus pelamis) adalah salah satu hasil tangkapan penting bagi nelayan di Samudera Hindia. Penelitian ini bertujuan untuk mengetahui perkembangan gonad dan panjang pertama kalimatang gonad cakalang di Samudera Hindia. Sampel cakalang dikumpulkan dari beberapa tempat di Pantai Selatan Jawa yaitu: Palabuhanratu, Cilacap, Pacitan, Sendang Biru, Kedonganan, Tanjung Luar, Labuhan Lombok dan Oeba dari bulan April 2012 sampai November 2013. Panjang cagak dari 136 sampel berkisar antara 35-68 cm. Tingkat kematangan gonad (TKG) diamati secara histologi dan analisis Gonadosomatic index (GSI). Hasil penelitian ini menunjukkan bahwa TKGcakalang didominasi oleh TKGIV sebesar 43%, diikuti dengan TKG III (21%), TKG I (17%), TKG II (16%) dan TKG V (2%). Panjang pertama kali matang gonad terjadi pada ukuran 42,9 cm. Skipjack tuna (Katsuwonus pelamis) is the one of the important catch for fishermen in the Indian Ocean. The objectives of this research are to investigate gonad maturity and length at first maturity for female cakalang in Indian Ocean. Skipjack tuna were sampled from several places in South Coast of Java i.e.: Palabuhanratu, Cilacap, Pacitan, Sendang Biru, Kedonganan, Tanjung Luar, Labuhan Lombok and Oeba from April 2012 to November 2013. Fork length of the sampled 136 fish ranged from 35 to 68 cm.Maturity stage (TKG) investigate using histological analysis and Gonadosomatic index (GSI) calculation. The results showed that maturity stage of skipjacktuna dominated by TKG IV with 43%, followed by TKG III (21%), TKG I (17%), TKG II (16%) dan TKG V (2%). Length at first maturity occurred at 42.9 cm.


2012 ◽  
Vol 14 (1) ◽  
pp. 107 ◽  
Author(s):  
Muhammad Jamal ◽  
Muhammad Fedi Alfiadi Sondita ◽  
John Haluan ◽  
Budy Wiryawan

The Bone Bay is part of Fisheries Management Zone WPPI 713 that covers Makassar strait, Flores sea and Bali sea. To such vast marinearea, fisheries management can be started from smaller region, e.g. embayment waters. Biological characteristics of skipjack tuna (Katsuwonuspelamis) are some of important information for developing fisheries management in the area. This research was aimed to determine length-weight relationship, size composititon, growth pattern and biologically feasible size of the fish. Data were obtained from fish caught byfisherman from Januari to December 2007. The bay was divided into three study areas, i.e. Northern, Centre and Southern Zones. The bcoefficients for length-weight relationship in the three zones were equal 3 [not significant]. The average fork-length (FL) in each zoneshowed similar trends: increased from January to June, then stabilized until December. Using von Bertalanffy’s growth model, the maximumFL (L ∞ of 759.75 mm is estimated for fish at age of 84 months. The length at first maturity of the fish is 465 mm (FL).


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2543 ◽  
Author(s):  
Jennifer C. Potts ◽  
Michael L. Burton ◽  
Amanda R. Myers

Ages of schoolmaster (n= 136) from the southeastern Florida coast from 1981–2015 were determined using sectioned sagittal otoliths. Opaque zones were annular, forming March–July (peaking in May–June). Schoolmaster ranged in age from 1–42 years; the largest fish measured 505 mm total length (TL) and was 19 years old. The oldest fish measured 440 mm TL. Estimated body size relationships for schoolmaster were:W= 9.26 × 10−6TL3.11(n= 256,r2= 0.95);W= 2.13 × 10−5FL2.99(n= 161,r2= 0.95);TL= 1.03FL+ 10.36 (n= 143,r2= 0.99); andFL= 0.96TL− 8.41 (n= 143,r2= 0.99), whereW= whole weight in g,FL= fork length in mm, and TL in mm. The fitted von Bertalanffy growth equation was:Lt= 482 (1 −e−0.12(t+2.79)) (n= 136). Based on published life history relationships, a point estimate of natural mortality for schoolmaster wasM= 0.10, while age-specific estimates ofMranged from 1.57–0.18 for ages 1–42.


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