scholarly journals Development of Enzymes andIn VitroDigestibility during Metamorphosis and Molting of Blue Swimming Crab (Portunus pelagicus)

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Phanu Chamchuen ◽  
Boonyarath Pratoomchat ◽  
Arunee Engkakul ◽  
Uthaiwan Kovitvadhi ◽  
Krisna Rungruangsak-Torrissen
Keyword(s):  
Digestive Enzymes ◽  
Raw Materials ◽  
Carapace Width ◽  
Protein Digestibility ◽  
Swimming Crab ◽  
Molting Cycle ◽  
Portunus Pelagicus ◽  
Larval Stages ◽  
Specific Activities

The work focuses on development of digestive enzymes (amylase, total protease, trypsin, and chymotrypsin) and activity ratio of trypsin to chymotrypsin (T/C ratio) for digestive efficiency and growth, in blue swimming crab (Portunus pelagicus) during metamorphosis and molting. Specific activities of all enzyme parameters studied were associated with growth during metamorphosis, while only those of trypsin and T/C ratio were associated during molting cycle where trypsin and chymotrypsin specific activities associated with consumption rate with especially high levels during late intermolt and early premolt stages. About 50% increased weight gain was observed with at least double increased T/C ratio at the end of molting period, compared to the stages prior to molting. Growth of carapace would be more significant after finishing molting. Carapace width gain and T/C ratio were highest at the first crab stage. Studies ofin vitroprotein digestibility of different feed raw materials indicated thatArtemia, Rotifer, andMoinaare the best for larval stages. Otherwise, the use of shrimp feed andArtemiaflake could be the alternatives. Incorporating of cassava meal into the feed formula for early adult stage (juvenile) could be an advantage. The proteins from animals are more beneficial for adult crab culture than the proteins from plants and bacteria. The digestible quality of dietary protein is very important during larval stages, while the protein level of diet is more important during adult stages with fully developed digestive enzymes.

Biologi Rajungan Portunus pelagicus Linnaeus, 1758 (Crustacea: Portunidae) Ditinjau Dari Aspek Distribusi Ukuran Dan Parameter Pertumbuhan Di Perairan Rembang, Jawa Tengah

2019 ◽  
Vol 8 (4) ◽  
pp. 402-408
Author(s):  
Nathanael Ganang Anindityo Wibowo ◽  
Chrisna Adhi Suryono ◽  
Ibnu Pratikto
Keyword(s):  
Size Structure ◽  
Carapace Width ◽  
Growth Parameter ◽  
Survey Method ◽  
Average Weight ◽  
Swimming Crab ◽  
Female Crab ◽  
Potential Yield ◽  
Portunus Pelagicus ◽  
Male Crab

Rembang merupakan salah satu kabupaten di Jawa Tengah yang dikenal sebagai daerah penghasil sumberdaya rajungan yang cukup tinggi permintaannya dan terus meningkat setiap tahunnya. Hal tersebut dapat menyebabkan terjadinya penurunan potensi hasil rajungan akibat intensifnya penangkapan di Perairan Rembang. Kajian tentang kondisi stok sumberdaya rajungan  terkait sebaran dan dinamika populasi ini sangat diperlukan dalam pengelolaan potensi rajungan. Tujuan dari penelitian ini adalah untuk menganalisis struktur ukuran dan parameter pertumbuhan rajungan di Perairan Rembang. Penelitian ini dilaksanakan pada bulan Maret – Juni 2019 di Perairan Rembang, dengan menggunakan metode survei yang bersifat deskriptif. Total sampel rajungan selama penelitian adalah 1200 ekor yang terdiri dari 574 ekor jantan dan 624 ekor betina. Hasil penelitian menunjukkan kelas ukuran lebar karapas rajungan didominasi oleh rajungan muda, dengan rata – rata 105.01 ± 11.99 mm untuk jantan dan 107.73 ± 10.68 untuk betina. Berat rata – rata rajungan jantan yaitu sebesar 95.2 ± 27.1 gram dan rajungan betina sebesar 97.9 ± 23.1 gram, sehingga menunjukkan rajungan jantan lebih kecil dibandingkan dengan rajungan betina. Pola pertumbuhan rajungan di Perairan Rembang bersifat allometrik negatif. Laju pertumbuhan rajungan di Perairan Rembang yang didapatkan adalah berupa nilai panjang asimptotik (L∞) sebesar 71.4 mm dengan koefisien pertumbuhan (K) sebesar 1.5/tahun.Rembang is a coastal region in Central Java which known as to producer of blue swimming crab resources that are in high demand and continues to increase every year. It will because decreasing the potential yield of blue swimming crab due to intensive fishing in Rembang Waters. Study on the stock condition of the blue swimming crab resource related to the distribution and dynamics of the population is required for the management of the blue swimming crab potential. The current research aims to assess the size structure and growth parameter of blue swimming crab in the Rembang Waters. The research was conducted from March to June 2019 in Rembang Waters, using a descriptive survey method. The total number of crab samples during the study was 1200 animals consisting of 574 male and 624 female. The results showed that the size of the crab carapace width class was dominated by young crabs, with an average of 105.01 ± 11.99 mm for males and 107.73 ± 10.68 for females. The average weight of male crab is 95.2 ± 27.1 gram and female crab is 97.9 ± 23.1 gram, indicates that male crab is smaller than female crab. The crab’s growth in Rembang Waters is allometric negative. The growth rate of crab in the Rembang Waters obtained is in the form of asymptotic length (L∞) was 71.4 mm with a growth coefficient (K) 1.5/year.

scholarly journals Stock Status of Blue Swimming Crab (Portunus pelagicus Linnaeus, 1758) in Tiworo Strait Waters, Southeast Sulawesi, Indonesia

2020 ◽  
Vol 25 (2) ◽  
pp. 85-90
Author(s):  
Yustika Permatahati Intan Permatahati ◽  
Nila Nikmatia Bugis ◽  
La Sara ◽  
Tezza Fauzan Hasuba Hasuba
Keyword(s):  
Carapace Width ◽  
Growth Patterns ◽  
Fishing Ground ◽  
Swimming Crab ◽  
Portunus Pelagicus ◽  
Male And Female ◽  
Gonad Maturity ◽  
Stock Status ◽  
Spawning Potential Ratio ◽  
Very High

The blue swimming crab (BSC) fishery in Tiworo Strait has been heavily exploited since two decades ago when its worldwide demand and price was very high. Study on population aspects of this organism in this waters is limited. The aim of present study was to investigate growth patterns, population stock status, and size at first gonad maturity of Portunus pelagicus. One of the main fishing ground of BSC around Tiworo Strait waters is at Bangko and Gala Islands. Samples of BSC were taken monthly using gillnet and collapsible trap. Each sample taken was identified its sex, measured its carapace width, and weighed. Data collected from fishing ground of BSC were analyzed to find out growth patterns, population stock status using spawning potential ratio (SPR) method, and the first gonad maturity (CW50). The results of study showed that growth patterns of BSC male and female following isometric growth patterns (b=0) (P<0.05). It was found out that SPR of BSC from both fishing ground was 22.46% and 23.71%, respectively which indicates that population stock status of BSC in Tiworo strait waters is “moderate level” (SPR > 20%). The size at first gonad maturity (CW50) was attained at carapace width of 9.16 cm for male and 10.16 cm for female. Those imply that BSCs allowed to be caught should be >10 cm. 

scholarly journals Studies on Biological Test of Formulated Diets Supplementation of Vitamin E for the Broodstock of Females Blue Swimming Crab, Portunus pelagicus (Linnaeus, 1758)

F1000Research ◽  
2018 ◽  
Vol 7 ◽  
pp. 1780 ◽  
Author(s):  
Efrizal Efrizal ◽  
Indra Junaidi Zakaria ◽  
Rusnam Rusnam ◽  
Suryati Suryati ◽  
Nofa Yolanda
Keyword(s):  
Vitamin E ◽  
Carapace Width ◽  
Coastal Region ◽  
Mass Scale ◽  
Dietary Vitamin ◽  
Swimming Crab ◽  
Female Crab ◽  
Portunus Pelagicus ◽  
Formulated Diets ◽  
Formulated Diet

Background: Currently, great progress in the artificial propagation of commercially important   portunid crabs of the genus Portunus has been achieved, and various methods have been adopted in mass-scale hatchery activities. This study analyzed the biological testing of formulated diets with different dose supplementations of vitamin E for the broodstock of female blue swimming crabs, P. pelagicus (Linnaeus, 1758) Methods: Female crab samples were collected from the coastal region of Padang, West Sumatra. The method used in this study was completely randomized design, with four treatment regimens (n=5 crabs each) of dietary vitamin E (0, 300, 600, and 900 IU/kg formulated diets). Results: The results show that the supplementation of vitamin E in the formulated diet had a significant effect (P <0.05) on the absolute weight growth, carapace length and carapace width. Conclusions: Supplementation of vitamin E on in formulated diet causes broodstock blue swimming crab molting, with a percentage value of 40–80% on day 20 and 20% on day 30, with a 100% survival rate.

scholarly journals VARIABILITY OF CARAPACE WIDTH SIZE AND ABUNDANCE OF BLUE SWIMMING CRABS (Portunus pelagicus Linnaeus) IN PATI WATERS

2016 ◽  
Vol 7 (2) ◽  
Author(s):  
Dyah Ika Nugraheni ◽  
Achmad Fahrudin ◽  
. Yonvitner
Keyword(s):  
Coastal Waters ◽  
Accretion Rate ◽  
Carapace Width ◽  
Management Strategies ◽  
Fishing Effort ◽  
Swimming Crab ◽  
Nearshore Zone ◽  
Portunus Pelagicus ◽  
Males And Females ◽  
Swimming Crabs

<p><em>Fishing effort enhancement would put pressure on blue swimming crab resources and its ecosystem. The objective of this study was to determine the spatial distribution based on the size of the carapace width (CW), abundance, temperature, salinity, depth, and fishing intensity in Pati waters which was divided into two zones (zones 1=nearshore, zone 2=offshore). The result showed that the average of carapace width in zone 1 to zone 2 was significantly different (p &lt;0.05), as well as between males and females. Average number of individual (abundance) was significantly different according to fishing areas and sex (p &lt;0.05). The average of water temperature in zone 1 was higher than in zone 2, salinity in zone 1 was smaller than in zone 2, and the water depth in zone 1 was shallower than in zone 2. The higher the crab catch intensity leaded to the smaller the abundance and size of carapace width. Alternative management strategies were proposed such as to divert fishing grounds from coastal waters to offshore during low productivity season, to uphold rules on minimum legal size for catching (Lm = 107 mm),  to release of berried females catch, and to reduce accretion rate of gear and fishing fleet mainly in the coastal zone waters.</em></p><p><em><strong><em>Keywords:  </em></strong><em>blue swimming crab, carapace widht (CW), abundance, intensity of fishing</em></em></p>

scholarly journals Abundance and spatial distribution of blue swimming crab (Portunus pelagicus) larvae during east monsoon in the East Lampung waters, Indonesia

2018 ◽  
Vol 19 (4) ◽  
pp. 1326-1333 ◽  
Author(s):  
DURANTA D. KEMBAREN ◽  
ZAIRION ZAIRION ◽  
MOHAMMAD M. KAMAL ◽  
YUSLI WARDIATNO
Keyword(s):  
Spatial Distribution ◽  
Early Stage ◽  
Mass Density ◽  
Sampling Site ◽  
Water Environment ◽  
Larval Abundance ◽  
Swimming Crab ◽  
Portunus Pelagicus ◽  
Important Species ◽  
Larval Stages

Kembaren DD, Zairion, Kamal MM, Wardiatno Y. 2018. Abundance and spatial distribution of blue swimming crab (Portunuspelagicus) larvae during east monsoon in the East Lampung waters, Indonesia. Biodiversitas 19: 1326-1333. The blue swimmingcrab/BSC, Portunus pelagicus, is an economically important species in fishery industry and continuously being exploited, particularly inthe East Lampung waters. BSC research in Indonesia during the last decade was only restricted to the adult phase, while research ontheir larval dynamics in nature has not been done yet. This study aimed to assess the abundance and the distribution of BSC larvae, andto describe their correlation to its environmental conditions. This study was conducted in June 2017 (during east monsoon) in the EastLampung waters. Sampling was done in surface water during the daylight hours on nine sites with three replicates on each site. Planktonabundance and oceanographic profile were also recorded from the same sampling site. The result from this study showed that the waterquality from the environment was suitable for the development of BSC larvae. The abundance of the early-stage larvae (Z1-Z3) wasrelatively higher than the late-stage larvae (Z4 and M). The larval stages of BSC were dispersed and completed their development in themid-shore and offshore waters. There was a tendency that the early-stage was more abundant in the northern part, while the late-stagewas more abundant in the southern part of the study area. The highest larval abundance was found in the mid-shore, particularly in sitenumber five, which was influenced by the water mass density and current direction during the east monsoon. Moreover, oxygenconcentration and salinity of the water environment influenced the early-stage larvae abundance more than the late-stages abundance.

Kajian Morfometri dan Tingkat Kematangan Gonad Rajungan di Perairan Betahwalang, Demak

2021 ◽  
Vol 10 (2) ◽  
pp. 175-183
Author(s):  
Iqbal Maulana ◽  
Irwani Irwani ◽  
Sri Redjeki
Keyword(s):  
Time Series ◽  
Size Structure ◽  
Growth Parameters ◽  
Carapace Width ◽  
Economic Value ◽  
Survey Method ◽  
Swimming Crab ◽  
Female Crab ◽  
Portunus Pelagicus ◽  
Gonad Maturity

Rajungan (Portunus pelagicus) merupakan komoditas laut yang memiliki nilai ekonomis yang tinggi, dimana berbanding lurus dengan penangkapan yang terus meningkat. Tingkat pemanfaatan yang tidak mengindahkan ukuran dan kondisi rajungan dapat mempengaruhi struktur ukuran dan stok rajungan di suatu perairan. Penelitian ini bertujuan untuk mengetahui distribusi ukuran, hubungan lebar dan berat rajungan serta distribusi tingkat kematangan gonad (TKG) di perairan Betahwalang, Demak. Penelitian menggunakan metode survey dengan analisis yang bersifat deskriptif yang dilakukan secara “time-series”. Pengamatan sampel rajungan sebesar 10% dari hasil tangkapan yang didaratkan oleh setiap nelayan di pengepul rajungan.. Hasil dari penelitian ini menujukkan dari 3030 ekor rajungan yang diamati diketahui distribusi lebar karapas rajungan berkisar antara 35 – 185 mm dan kisaran berat sebesar 10 – 350 gram. Rajungan yang terdapat di perairan Betahwalang memiliki pertumbuhan yang bersifat allometrik positif pada rajungan jantan dan betina pada bulan Januari serta Februari.  Hasil nilai b sebesar 3,29 dan 3,08 (Januari & Februari) pada rajungan jantan. Nilai b sebesar 3,10 dan 3,15  pada rajungan betina (Januari & Februari) serta nilai b sebesar 3,14 pada keseluruhan rajungan. Sehingga diketahui pertumbuhan lebar karapas lebih cepat dibandingkan bobot rajungan. Sedangkan distribusi tingkat kematangan gonad rajungan betina adalah 21% pada TKG 1; 63% pada TKG 2; serta 16% pada TKG 3, dengan ukuran pertama kali matang gonad adalah 141,51 mm. Blue swimming crab (Portunus pelagicus) is a marine commodity has a high economic value , which is causing the crab catch to rise as well. The catch rate that does not consider the size and maturity of sea crab can affect the size structure and population stock of sea crab in waters. This study aims to determine the size distribution,the relationship of width and weight of Blue swimming crab and distribution of gonad maturity in Betahwalang, Demak. There’s a descriptive survey method used in this study with time-series observations. The sample size is about 10% of the total number landed crab from each fisherman. The results of this study showed that from 3030 crabs observed, the distribution of crab carapace width ranged from 35 – 185 mm and the weight range at 10 – 350 gram. The results showed the all crabs has a positive allometric on growth parameters. The value of  b 3,29 and 3,08 (January & February) in male blue swimming crab, 3.10 and 3.15 (January & February) on female sea crabs, and 3.14 on whole sea crabs. So it is known that the growth of carapid width is faster than the weight of crab. While the distribution of female crab gonad maturity level is 21% in level 1; 63% in level 2; and 16% in level 3, with the first size of mature gonad at 141,51 mm.

scholarly journals Studies on Biological Test of Formulated Diets Supplementation of Vitamin E for the Broodstock of Females Blue Swimming Crab, Portunus pelagicus (Linnaeus, 1758)

F1000Research ◽  
2019 ◽  
Vol 7 ◽  
pp. 1780 ◽  
Author(s):  
Efrizal Efrizal ◽  
Indra Junaidi Zakaria ◽  
Rusnam Rusnam ◽  
Suryati Suryati ◽  
Nofa Yolanda
Keyword(s):  
Vitamin E ◽  
Carapace Width ◽  
Coastal Region ◽  
Mass Scale ◽  
Dietary Vitamin ◽  
Swimming Crab ◽  
Female Crab ◽  
Portunus Pelagicus ◽  
Formulated Diets ◽  
Formulated Diet

Background: Currently, great progress in the artificial propagation of commercially important   portunid crabs of the genus Portunus has been achieved, and various methods have been adopted in mass-scale hatchery activities. This study analyzed the biological testing of formulated diets with different dose supplementations of vitamin E for the broodstock of female blue swimming crabs, P. pelagicus (Linnaeus, 1758) Methods: Female crab samples were collected from the coastal region of Padang, West Sumatra. The method used in this study was completely randomized design, with four treatment regimens (n=5 crabs each) of dietary vitamin E (0, 300, 600, and 900 IU/kg formulated diets). Results: The results show that the supplementation of vitamin E in the formulated diet had a significant effect (P <0.05) on the absolute weight growth, carapace length and carapace width. Conclusions: Supplementation of vitamin E on in formulated diet causes broodstock blue swimming crab molting, with a percentage value of 40–80% on day 20 and 20% on day 30, with a 100% survival rate.

scholarly journals STOCK STATUS OF BLUE SWIMMING CRAB (Portunus pelagicus) IN TANAH LAUT, SOUTH KALIMANTAN, AND ITS ADJACENT WATERS

2020 ◽  
Vol 26 (1) ◽  
pp. 51
Author(s):  
Ali Suman ◽  
Ap'idatul Hasanah ◽  
Andina Ramadhani Putri Pane ◽  
Pratiwi Lestari
Keyword(s):  
Carapace Width ◽  
Total Mortality ◽  
Growth Parameter ◽  
Fishing Effort ◽  
Swimming Crab ◽  
Chi Square ◽  
Portunus Pelagicus ◽  
Stock Status ◽  
Chi Square Test ◽  
First Maturity

A study on the stock status of blue swimming crab (Portunus pelagicus Linnaeus, 1758) was conducted in Tanah Laut, South Kalimantan waters, based on data collected in March to November 2017. The results showed that the growth pattern of blue swimming crab in Tanah Laut waters was negatively allometric and the sex ratio of males to females was 1.0 : 1.7. The chi-square test indicated that the total males and total females of the blue swimming crab was significantly different. It means that there was an imbalance in numbers between males and females. The estimated length at first capture (Lc) was 127.26 mm (carapace width; CW), smaller than the length at first maturity (Lm) at 133.24 mmCW. The growth parameter of blue swimming crab was 1.1year with a maximum carapace width (L) of 204.3 mmCW. The estimated instantaneous total mortality (Z) and natural mortality (M) were 3.04/year and 1.24/year, respectively. While fishing mortality (F) and exploitation rate (E) were 1.80/year and 0.59/year, respectively, the estimated spawning potential ratio (SPR) was 11.1 %. Therefore, the stock status was categorized as overfishing. In order to ensure the sustainability of the blue swimming crab, a precautionary approach,, such as reducing fishing effort by 18 % of the current situation, is strongly recommended to apply.

scholarly journals PARAMETER POPULASI DAN TINGKAT PENGUSAHAAN RAJUNGAN (Portunus pelagicus) DI PERAIRAN ASAHAN, SELAT MALAKA

2017 ◽  
Vol 9 (2) ◽  
pp. 93
Author(s):  
Andina Ramadhani Putri Pane ◽  
Heri Widiyastuti ◽  
Ali Suman
Keyword(s):  
Mortality Rate ◽  
Carapace Width ◽  
Total Mortality ◽  
Optimum Level ◽  
Market Demand ◽  
Swimming Crab ◽  
Portunus Pelagicus ◽  
Monthly Data ◽  
Management Measures ◽  
Exploitation Rate

Tingginya permintaan pasar terhadap rajungan mengakibatkan aktivitas penangkapannya berlangsung secara intensif. Selat Malaka merupakan salah satu daerah penangkapan rajungan yang penting di Indonesia. Tujuan penelitian ini adalah untuk mengestimasi parameter populasi dan tingkat eksploitasi rajungan (Portunus pelagicus) di perairan Asahan dan sekitarnya. Pengumpulan data bulanan dilakukan pada bulan Juni 2015 sampai dengan Nopember 2016. Hasil penelitian menunjukkan bahwa musim penangkapan berlangsung sepanjang tahun dengan puncak pada bulan Juli dan Oktober, puncak pemijahan terjadi pada bulan Januari dan Agustus. Ukuran lebar karapas pertama kali tertangkap dengan gillnet (Lc) dan ukuran pertama kali matang gonad (Lm) masing-masing sebesar 109,6 mm dan 104,1 mm. Laju pertumbuhan (K) sebesar 1,38/tahun dan lebar karapas asimtotik (L) sebesar 183,10 mm. Laju kematian total (Z) rajungan sebagai 4,31 per tahun, laju kematian karena penangkapan (F) dan laju kematian alami (M) masing-masing 2,96 per tahun dan 1,35 per tahun; laju eksploitasi (E) diestimasi sebesar 0,69. Tingkat pemanfaatan rajungan di perairan Asahan diduga telah melewati optimal, sehingga perlu dilakukan pengelolaan melalui pengurangan jumlah unit gillnet rajungan sebanyak 38% dari kondisi saat ini. Blue swimming crab faced intensive fishing pressure due to the high market demand. The Malacca Strait is one of important fishing area for blue swimming crab. The research aims to estimate the population parameters and exploitation rate of blue swimming crab (Portunus pelagicus) in the Asahan and adjacent waters. A monthly data were collected from June 2015 to November 2016 that caught by Gillnet. The results showed that the fishing season takes place throughout the year with peaks in July and October, meanwhile peak of spawning season in January and August. The carapace width at first capture (Lc) and first mature (Lm) were 109.6 mm and 104.1 mm, respectively. The growth rate (K) was 1.38 / year and the asymptotic length (L) was 183.10 mm. Total mortality rate (Z) was 4.31 per year, fishing mortality rate (F) and natural mortality rate (M) were 2.96 per year and 1.35 per year respectively; Exploitation rate (E) was estimated at 0.69. It means that the exploitation rate of swimming crab in the Asahan waters found exceed the optimum level, therefore the management measures needs to reduce effort (unit) of gillnet by a 38% of actual level. 

scholarly journals STRUKTUR UKURAN DAN BIOLOGI POPULASI RAJUNGAN (Portunus pelagicus Linnaeus, 1758) DI PERAIRAN KEPULAUAN ARU

2018 ◽  
Vol 1 (1) ◽  
pp. 51
Author(s):  
Duranta Diandria Kembaren ◽  
Adi Surahman
Keyword(s):  
Population Biology ◽  
Size Structure ◽  
Carapace Width ◽  
Total Mortality ◽  
Swimming Crab ◽  
Fishing Mortality ◽  
Portunus Pelagicus ◽  
Precautionary Approach ◽  
Exploitation Rate ◽  
Average Size

Penelitian struktur ukuran dan biologi populasi rajungan di perairan Kepulauan Aru telah dilakukan pada Januari-April, Juni dan Agustus-November 2016. Penelitian ini bertujuan untuk mengidentifikasi struktur ukuran dan biologi populasi yang meliputi pertumbuhan, laju kematian, dan tingkat eksploitasi rajungan. Pemahaman struktur ukuran dan biologi populasi dapat dijadikan dasar masukan untuk pengelolaan perikanan. Rata-rata ukuran lebar karapas rajungan yang tertangkap sebesar 136 mm untuk jantan dan 141 mm untuk betina. Rajungan yang tertangkap pada Januari dan Juni memiliki rata-rata ukuran yang lebih besar. Rata-rata rajungan yang tertangkap sudah melawati ukuran matang gonad (Lc = 133,4 mm > Lm = 119,9 mm). Puncak musim pemijahan terjadi pada Februari-Maret dan Agustus-September. Lebar karapas asimtosis (CW) sebesar 185 mm dengan laju pertumbuhan (K) 1,15 tahun-1 serta laju kematian total (Z) 4,94 tahun-1, laju kematian alamiah (M) 1,20 tahun-1 serta laju kematian akibat penangkapan (F) 3,74 tahun-1. Laju eksploitasi sudah berada pada kondisi lebih tangkap (E=0,76). Hasil kajian menyarankan bahwa pengelolaan perikanan rajungan perlu dilakukan secara hati-hati agar sumberdaya ini dapat lestari. Salah satu upaya yang dapat di tempuh adalah dengan menerapkan sistem penutupan musim penangkapan rajungan pada saat terjadinya puncak musim pemijahan yaitu pada Februari-Maret dan Agustus-September. Dengan demikian diharapkan proses regenerasi dan rekrutmen rajungan selalu dapat mendukung ketersedian stok sumberdaya rajungan di perairan Kepulauan Aru ini. Study on the size structure and population biology of blue swimming crab in the waters of Kepualuan Aru was conducted in January to April, June and August to November 2016. The aim of this study was to identify the size structure and population biology i.e. growth, mortality, and exploitation rate of blue swimming crab. Understanding on the size structure and population biology can be used as basic information for managing blue swimming crab fisheries.  Average size of carapace width of blue swimming crab was 136 mm for male and 141 mm for female. Catch on January and June  was bigger size than others months. Length at first capture was higher than length at maturity (Lc = 133,4 mm > Lm = 119,9 mm). Spawning peak season occurs in  February-March and August-September. Asymptotic carapace width (CW) of blue swimming crab was 185 mm with the growth rate (K) was 1,20 year-1, total mortality (Z) was 4,94 year-1, natural mortality (M) was 1,20 year-1, and fishing mortality (F) was 3,74 year-1. Exploitation rate was exceed the sustainability limit (E = 0,76). Thus, it is needed to manage the blue swimming crab fishery with precautionary approach. Based on this study, we suggest to apply the fishing closure system at the peak of spawning season. Thus, the regeneration process and recruitment will support the availability of blue swimming crabs resource in Kepualuan Aru waters.

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