Experimental fishing for the Spider crab, Maia Squinado: sea and laboratory trials

1984 ◽  
Vol 64 (2) ◽  
pp. 251-259 ◽  
Author(s):  
Deborah M. Rodhouse
Keyword(s):  
Sex Ratio ◽  
West Coast ◽  
Size Composition ◽  
Spider Crab ◽  
Catch Per Unit Effort ◽  
The West ◽  
Summer Peak ◽  
Unit Effort ◽  
Pot Trials ◽  
Rocky Outcrops

Sea trials, using baited pots (inkwell and French barrel) and nets (tangle and gill), were conducted for the spider crab Maia squinado off the west coast of Ireland from November 1978 to July 1980. A series of laboratory pot trials using inkwell pots were performed. Diving observations were made on the fishing grounds.Catch per unit effort rose to a summer peak and decreased in autumn. There was no difference in size composition or sex ratio of the catch between the pots and nets. Mature males predominated in the catch with the highest male:female (M:F) ratios recorded in summer. Immatures were virtually absent from the catch. Segregation on the basis of sex and maturity appears to occur in summer. Mature males were found at about 10 m, in sandy areas with rocky outcrops. Mature females occurred at about 5 m, on a sand and shell gravel bottom with rock and weed (notably Laminaria). Immatures were rare and occurred just below the intertidal. The M:F ratio was lowest during the periods of the onshore and offshore migrations. Berried females were recorded from March to September with one brood produced each year.Laboratory pot trials showed increased aggression among spider crabs in the presence of baited pots. Males drove other males away from pots and divided their time between agonistic encounters and searching. Females were not driven away and did not engage in aggressive encounters. This behaviour, and the observation that large males could reach the bait through the pot bars, possibly explains the absence of larger and smaller males from the pots.

scholarly journals NISBAH KELAMIN, UKURAN PERTAMA KALI TERTANGKAP DAN CATCH PER-UNIT EFFORT DUA JENIS LOBSTER KIPAS (SCYLLARIDAE) DI PERAIRAN KUPANG DAN SEKITARNYA

2019 ◽  
Vol 25 (1) ◽  
pp. 27
Author(s):  
Ngurah N Wiadnyana ◽  
Setiya Triharyuni ◽  
Prihatiningsih Prihatiningsih
Keyword(s):  
Sex Ratio ◽  
Catch Per Unit Effort ◽  
Biological Aspect ◽  
Unit Effort ◽  
By Catch

Pemanfaatan lobster kipas (Scyllaridae) yang tertangkap di Perairan Kupang terus meningkat, tetapi informasi mengenai kondisi stok dan aspek biologi nya belum banyak diketahui. Tulisan ini mengkaji nisbah kelamin, rata-rata ukuran pertama kali tertangkap dan catch per-unit of effort (CPUE) lobster kipas di perairan Kupang dan sekitarnya. Kedua spesies lobster kipas yang dianalisis merupakan hasil tangkapan sampingan jaring krendet yang dilakukan oleh nelayan setempat. Jenis data yang dianalisis meliputi data penangkapan dan biologi lobster yang dikumpulkan selama periode Oktober 2015 - Desember 2016. Hasil penelitian menunjukkan bahwa terdapat dua jenis lobster kipas hasil tangkapan sampingan di perairan Kupang, yaitu Scyllarides haanii dan Thenus indicus dengan komposisi hasil tangkapan T. indicus lebih banyak dari S. haanii. Rata-rata ukuran panjang pertama kali tertangkap (Lc) untuk lobster T. indicus betina berdasarkan panjang karapas adalah sekitar 93,79 dan 94,18 mm untuk jantan, sedangkan untuk lobster S. haanii betina adalah 101,40 mm dan 104,06 mm untuk jantan. Nisbah kelamin dari kedua jenis lobster ini masih dalam kondisi seimbang. Rata-rata nilai CPUE lobster jenis T. indicus 3,7 kg/trip lebih besar dibandingkan dengan nilai CPUE S. haanii sebesar 0,8 kg/trip. Nilai CPUE dari tiap-tiap lokasi penangkapan tidak berbeda nyata antar lokasi penangkapan.The utilization of slipper lobster (Scyllaridae) caught in around Kupang waters is increased continuously, however a little information on its stock and biological aspect is available. This paper describes sex ratio, length at first capture and the catch per-unit of effort (CPUE) of the slipper lobster population in the Kupang and surrounding waters. Both slpper lobsters analyzed are a by-catch of a gillnet operated by local fishermen. The data analysized included cacth and biology of lobster collected during the period of October 2015 to December 2016. Results show that there were two types of slipper lobster as by-catch in Kupang waters, namely Scyllarides haanii and Thenus indicus with the number of T. indicus higher than S. haanii. The first lengths of captured (Lc) for female T. indicus based on carapac lenght was 93.79 and 94.18 mm for male, while female S. haanii were 101.40 mm (female) and 104.06 mm for male. The sex ratio of both types of lobsters was still in a balanced condition. The average CPUE of T. indicus was 3.7 kg/trip, higher than that CPUE value of S. haanii of only 0.8 kg/trip. The CPUE value was significantly no different between the fishing location.

scholarly journals Pêche Et Caractéristiques Morphologiques D’un Poisson-Chat Endémique Synodontis Punctifer (Daget, 1964) Dans Le Barrage Électrique De Taabo (Côte d’Ivoire)

2018 ◽  
Vol 14 (15) ◽  
pp. 101
Author(s):  
Hervé Oussou Koffi ◽  
Diaha N’guessan Constance ◽  
Soro Yaya ◽  
N’Da Konan
Keyword(s):  
Sex Ratio ◽  
Condition Factor ◽  
Morphological Characteristics ◽  
Fishing Effort ◽  
Annual Production ◽  
Allometric Growth ◽  
Catch Per Unit Effort ◽  
Large Size ◽  
Unit Effort ◽  
Significant Difference

A study of Synodontis punctifer (family: Mochokidae) of Taabo Lake was conducted from October 2015 to September 2016. This was carried out so as to evaluate its quantity (biomass) caught by fishing and also its morphological characteristics. The fish were caught using gillnets at 4 sites of the lake and different measurements were made. The fishing effort was 23 to 11 fishermen / day in Taabo city, 17 to 11 fishermen / day in Courandjourou, 13 to 5 fishermen / day in Ahondo, and 8 to 3 fishermen / day in Taabo village. The catch per unit effort (CPUE) ranged from 17.7 to 3.7 g / fisherman / day, 9.2 to 1.2 g / fisherman / day, 8.3 to 0.7 g / fisherman /day, 8 to 1g / fisherman / day at Ahondo, Courandjourou, Taabo city and Taabo village, respectively. The overall annual production was estimated at 2199.3 kg, i.e. 817 kg (40%) at Ahondo, 788.3 kg (35%) at Courandjourou, 462.5 kg (20%) at Taabo, and 131.5 kg (5%) in Taabo village. The overall sex ratio (1: 1.33) was in favor of females. Individuals have negative allometric growth at all sites with values ranging from 1.72 to 2.89. The condition factor does not vary significantly between different categories of individuals (ANOVA, F = 2.79, p ˃ 0.05). A significant difference was observed between the average sizes of the individuals of the different sites (test, p˂0,05). The large size specimens were captured at Ahondo, mean (avg = 15.38 ± 1.68 cm FL). In Courandjourou, the sizes were intermediate (avg = 13.63 ± 1.64 cm LF). Smalls sizes have been observed in Taabo city (mean= 12.37 ± 1.24 cm FL) and Taabo village (mean= 15.58 ± 1.58 cm FL).

scholarly journals VARIASI HASIL TANGKAPAN IKAN DARI PERAIRAN SAMUDERA HINDIA, YANG DIDARATKAN DI PPN SIBOLGA PANTAI BARAT SUMATERA TAHUN 2019

2021 ◽  
Vol 17 (2) ◽  
pp. 68-76
Author(s):  
Ria R Manik ◽  
Ewin Handoco ◽  
Jogi Arleston
Keyword(s):  
Fishing Ground ◽  
Skipjack Tuna ◽  
Business Unit ◽  
Catch Per Unit Effort ◽  
The West ◽  
Monthly Average ◽  
Research Material ◽  
Unit Effort ◽  
West Sumatra ◽  
The Indian Ocean

Overfishing and overcapacity is a problem for the sustainability of capture fisheries development. Indonesia has experienced overfishing or called overfishing and overcapacity or called excess fishing capacity. The west coast of the island of Sumatra has enormous fishing potential, both in territorial waters and in ZEE waters. The purpose of the study was to understand the trend of fluctuations in fish catches in the waters of West Sumatra. Assessing the effect of boat trips on fish catches in the waters of West Sumatra and providing basic information and management of fisheries in the waters of West Sumatra. The research material used is Catch per Unit Effort (CPUE) data. The overall data was monthly average data in 2019 with fishing ground areas in the Western waters of Sumatra, the Indian Ocean. The results showed the composition of catches in the waters of West Sumatra landed in PPN Sibolga there are three dominant types of fish, namely skipjack tuna 14.566.140 kg (49.90%), decapterus 6.404.470 kg (21.94%) and tunny 2.480.880 kg (8.50%), The dynamics of fish catches in PPN Sibolga in 2019 were highest in May at 3.945.143 kg and June was the lowest catch month of 1.093.292 kg and the average monthly catch in 2019 was 2.508.436 kg, the catch per business unit landed in PPN Sibolga in 2019 obtained the highest CPUE of 8.474 kg/trip (July 2019) and the lowest 1,755 kg/trip (June 2019).   ABSTRAK Overfishing dan overcapacity erupakan masalah keberlanjutan pembangunan perikanan tangkap. Indonesialah mengalami overfishing atau disebut penangkapan berlebih dan overcapacity atau disebut kelebihan kapasitas penangkapan.  Pantai Barat Pulau Sumatera memiliki potensi perikanan yang sangat besar, baik perairan teritorial maupun perairan ZEE. Tujuan dari penelitian adalah untuk memahami trend fluktuasi hasil tangkapan ikan di Perairan Barat Sumatera, mengkaji pengaruh trip kapal dengan hasil tangkapan ikan di Perairan Barat Sumatera dan memberikan informasi dasar dan pengelolaan perikanan di Perairan Barat Sumatera. Materi penelitian yang digunakan adalah data Catch per Unit Effort (CPUE). Keseluruhan data merupakan data rata-rata bulanan tahun 2019 dengan daerah fishing ground Perairan Barat Sumatera Samudera Hindia. Hasil penelitian menunjukkan komposisi hasil tangkapan di Perairan Barat Sumatera yang didaratkan di PPN Sibolga terdapat tiga jenis ikan yang dominan yaitu cakalang 14.566.140 kg (49,90%), layang 404.470 kg (21,94%) dan tongkol 2.480.880 kg (8,50%), Dinamika hasil tangkapan ikan di PPN Sibolga di tahun 2019  tertinggi terjadi pada bulan Mei sebesar 3.945.143 kg dan bulan Juni merupakan bulan hasil tangkapan terendah yaitu 1.093.292 kg dan rata-rata hasil tangkapan bulanan tahun 2019 adalah 2.508.436 kg, Hasil tangkapan per-unit usaha yang didaratkan di PPN Sibolga di tahun 2019 didapatkan CPUE tertinggi yaitu 8.474 kg/trip (Juli 2019) dan terendah 1.755 kg/trip (Juni 2019). Kata Kunci: CPUE, penangkapan berlebih, penangkapan ikan, PPN Sibolga, Perairan Barat Sumatera  

The population structure and parasitic relationships of oyster (Crassostrea angulata), Arcotheres sinensis (Pinnotheridae), and Rhopalione sinensis (Bopyridae) at the oyster reefs of western Taiwan

Crustaceana ◽  
2018 ◽  
Vol 91 (12) ◽  
pp. 1433-1451 ◽  
Author(s):  
Ai-Ling Kuo ◽  
Feng-Jiau Lin ◽  
Jung-Ting Hsu ◽  
Yi-Shin Chan ◽  
Yih-Tsong Ueng
Keyword(s):  
Population Structure ◽  
Sex Ratio ◽  
West Coast ◽  
Oyster Reefs ◽  
The West ◽  
Crassostrea Angulata ◽  
Pea Crab

Abstract This study examined the relationships among hosts, parasites, and hyperparasites of oyster farming on the west coast of Taiwan from June 2012 to August 2013. In a region of Taisi (Taiwan), which was composed of near coast and far coast racks, a total of 77 155 oysters were collected. Among them, 1166 oysters were parasitized by pea crabs, with the rate of parasitism of oysters by the pea crab, Arcotheres sinensis (Shen, 1932) being 1.51%. A total 1523 pea crabs were collected with a sex ratio of females to males of 1.03 : 1. A total of 285 bopyrid isopod parasites Rhopalione sinensis Markham, 1990 were collected from the pea crabs. The hyperparasitic rate of female pea crabs was 22.1%, and the sex ratio of female to male isopods was 1.16 : 1. Most of the pea crabs entered their hosts when the crabs were small, which allowed them to grow within the host.

scholarly journals DINAMIKA PERIKANAN KERAPU DI TAMAN NASIONAL KARIMUNJAWA (Grouper Fishery Dynamics in Karimunjawa National Park)

2016 ◽  
Vol 4 (2) ◽  
pp. 175
Author(s):  
Irfan Yulianto ◽  
Budy Wiryawan ◽  
Am Azbas Taurusman ◽  
Prihatin I. Wahyuningrum ◽  
Vita R. Kurniawati
Keyword(s):  
National Parks ◽  
National Park ◽  
Statistical Tests ◽  
Monsoon Season ◽  
Fishing Gear ◽  
Catch Per Unit Effort ◽  
The West ◽  
Unit Effort ◽  
Target Fish ◽  
Java Sea

<p>ABSTRACT<br />Karimunjawa National Park is one of the national parks that have the objective to maintain fish populations in the Java Sea, where one of them is grouper. Grouper is one of the target fish in the national park. The objective of this study is to assess the conditions and dynamics of the grouper fishery in Karimunjawa National Park. Fish landing surveys were conducted to collect the data. Fishing gear types, grouper species, and weight of each species were collected. Calculation of Catch per Unit Effort (CPUE) per month and two-way ANOVA statistical tests were used for data analysis. Results of this study indicated that catches of grouper using speargun was significantly higher than the catch using handline. There was a seasonal cycle of the grouper catch, where the value of the highest CPUE occurred in transitional season between the west and east monsoon season, from March to May.<br />Key words: CPUE, grouper fishery, Karimunjawa National Park</p><p>-------</p><p><br />ABSTRAK<br />Taman Nasional Karimunjawa merupakan salah satu taman nasional yang salah satu tujuannya untuk mempertahankan populasi ikan di Laut Jawa, dimana salah satunya adalah perikanan kerapu. Ikan kerapu merupakan salah satu target penangkapan di perairan Taman Nasional Karimunjawa. Tujuan penelitian ini adalah mengetahui kondisi dan dinamika perikanan kerapu di Taman Nasional Karimunjawa. Survei pendaratan ikan dilakukan untuk pengumpulan data. Data yang dikumpulkan dalam penelitian ini adalah alat tangkap yang digunakan untuk menangkap ikan kerapu, jenis hasil tangkapan, dan berat masing-masing jenis hasil tangkapan setiap trip. Perhitungan nilai Catch per Unit Effort (CPUE) setiap bulan dan uji statistik two ways ANOVA digunakan untuk analisis data. Hasil penelitian ini menunjukkan bahwa hasil tangkapan ikan kerapu dengan menggunakan speargun lebih tinggi dan berbeda nyata secara statistik dibandingkan hasil tangkapan dengan menggunakan pancing. Terdapat siklus musiman hasil tangkapan, dimana nilai CPUE tertinggi terjadi pada musim peralihan antara musim barat dan musim timur yakni dari bulan Maret hingga Mei.<br />Kata kunci: CPUE, perikanan kerapu, Taman Nasional Karimunjawa</p>

The New South Wales Trawlfishery: Review of Past Course and Examination of Present Condition

1955 ◽  
Vol 6 (2) ◽  
pp. 165 ◽  
Author(s):  
TW Houston
Keyword(s):  
New South ◽  
New South Wales ◽  
Size Composition ◽  
Fishing Effort ◽  
Present Condition ◽  
Catch Per Unit Effort ◽  
Nineteen Thirties ◽  
Unit Effort ◽  
South Wales ◽  
Post War

The past course of the New South Wales mixed trawlfishery is reviewed mainly on the basis of the available catch and fishing effort statistics. The size composition of tiger flathead landings from 1946-47 to 1953-54, and the age composition for certain post-war years, are analysed in conjunction with catch per unit effort data. The results suggest that 1943-44, 1944-45, 1947-48, and 1948-49 were relatively poor brood years, and 1945-46 and 1946-47 relatively good. The fluctuations in availability of tiger flathead (Neoplatycephalus macrodon (Ogilby) ) are accounted for after making certain valid assumptions. It is considered probable that the unexpectedly low catches of tiger flathead in the immediate post-war years were due to inefficiency of the few steam trawlers then working, and that Danish seiners were unable to exploit fully the available V+ and higher age-group fish. An examination of the present situation indicates that the New South Wales stock of tiger flathead is at a low level and is likely to reach even lower levels in the future if fishing intensity remains as high as in 1953-54. An improvement of the existing catch per unit effort would be expected if fishing intensity was reduced to the level of the middle nineteen-thirties (i.e. approx. 3500 trawler-tons) . Other regulative measures would need to be introduced to bring about an improvement in the annual catch of tiger flathead. These measures should aim at ensuring a more favourable weight-length relation.

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