scholarly journals The Stock Status of Skipjack Tuna (Katsuwonus pelamis) in Tomini Bay and Its Surrounding Areas, Indonesia

2021 ◽  
Vol 934 (1) ◽  
pp. 012085
Author(s):  
S Mardlijah ◽  
A R P Pane ◽  
A S Panggabean
Keyword(s):  
Population Dynamics ◽  
Landing Site ◽  
Total Sample ◽  
Utilization Rate ◽  
Skipjack Tuna ◽  
Katsuwonus Pelamis ◽  
Stock Status ◽  
Fish Recruitment ◽  
Surrounding Areas ◽  
And Control

Abstract Skipjack tuna (Katsuwonus pelamis) is an essential part of tuna, skipjack tuna, and mackerel tuna trades in Indonesia as the species is an economic commodity with export value. Tomini Bay is one of the areas in Indonesia with intensive skipjack tuna exploitation activities using purse seine fleets. Such a high fishing rate requires management efforts to maintain the species population’s sustainability. This study was conducted in April 2018–December 2019 at a fish landing site in Gorontalo City with a total sample of 8,833 skipjack tunas. The population dynamics, recruitment, and utilization rate were analyzed using FISAT II application and ELEFAN program. The results showed that the length at first capture (Lc) was 31.8 cmFL (in 2018) to 32.2 cmFL (in 2019) at around 1.3 year old. The fish recruitment occurred all year long, peaking in May at 16.12%. In addition, the utilization rate (E) of the species was 0.47, meaning that the species was already moderate to fully exploited. The suggested practical management efforts to maintain the population of the skipjack tunas in the area are to stop the fishing efforts from growing and control the size of the mesh for fishing.

scholarly journals KOMPOSISI UKURAN CAKALANG (Katsuwonus pelamis) HASIL TANGKAPAN HUHATE YANG DIDARATKAN DI TULEHU, AMBON

2017 ◽  
Vol 3 (3) ◽  
pp. 199 ◽  
Author(s):  
Budi Nugraha ◽  
Siti Mardlijah ◽  
Enjah Rahmat
Keyword(s):  
Total Sample ◽  
Fish Length ◽  
Small Fish ◽  
Skipjack Tuna ◽  
Katsuwonus Pelamis ◽  
Weight Relationship ◽  
Result Show ◽  
The Individual ◽  
Relationship Of ◽  
Length Frequency Data

Eksploitasi sumber daya ikan cakalang (Katsuwonus pelamis) di perairan Laut Banda telah berlangsung lama. Saat ini sumber daya ikan cakalang telah memperlihatkan tanda-tanda overfishing. Indikasi ini antara lain ditandai oleh penurunan hasil tangkapan dan ukuran individu, perubahan komposisi hasil tangkapan, serta kecenderungan meningkatnya proporsi beberapa jenis ikan berukuran kecil. Data frekuensi panjang dikumpulkan dari bulan Maret sampai Desember 2007 berjumlah 4.293 ekor. Pengukuran panjang dan bobot untuk mengetahui hubungan panjang dan bobot ikan dilakukan pada bulan Maret, Mei, Juli, dan Desember 2007 dengan jumlah contoh 296 ekor. Tulisan ini menyajikan informasi tentang distribusi ukuran panjang dan bobot, hubungan panjang dan bobot ikan cakalang dan ukuran pertama kali tertangkap (Lc) hasil tangkapan huhate yang beroperasi di perairan Laut Banda. Hasil analisis menunjukan bahwa ikan cakalang mempunyai kisaran panjang cagak (FL) antara 30-78 cmFL dan kisaran bobot antara 600-4300 g. Analisis regresi hubungan panjang dan bobot diperoleh persamaan W=0,0485 L2,751, R2=0,9427 dengan nilai koefisien regresi (r)=0,9709, dan nilai slope (b)=2,751. Dari hasil analisis tersebut diketahui bahwa pola pertumbuhan ikan cakalang bersifat allometrik negatif. Ukuran pertama kali tertangkap (Lc) ikan cakalang oleh huhate adalah 41,7 cmFL. Eksploitasi sumber daya ikan cakalang (Katsuwonus pelamis) di perairan Laut Banda telah berlangsung lama. Saat ini sumber daya ikan cakalang telah memperlihatkan tanda-tanda overfishing. Indikasi ini antara lain ditandai oleh penurunan hasil tangkapan dan ukuran individu, perubahan komposisi hasil tangkapan, serta kecenderungan meningkatnya proporsi beberapa jenis ikan berukuran kecil. Data frekuensi panjang dikumpulkan dari bulan Maret sampai Desember 2007 berjumlah 4.293 ekor. Pengukuran panjang dan bobot untuk mengetahui hubungan panjang dan bobot ikan dilakukan pada bulan Maret, Mei, Juli, dan Desember 2007 dengan jumlah contoh 296 ekor. Tulisan ini menyajikan informasi tentang distribusi ukuran panjang dan bobot, hubungan panjang dan bobot ikan cakalang dan ukuran pertama kali tertangkap (Lc) hasil tangkapan huhate yang beroperasi di perairan Laut Banda. Hasil analisis menunjukan bahwa ikan cakalang mempunyai kisaran panjang cagak (FL) antara 30-78 cmFL dan kisaran bobot antara 600-4300 g. Analisis regresi hubungan panjang dan bobot diperoleh persamaan W=0,0485 L2,751, R2=0,9427 dengan nilai koefisien regresi (r)=0,9709, dan nilai slope (b)=2,751. Dari hasil analisis tersebut diketahui bahwa pola pertumbuhan ikan cakalang bersifat allometrik negatif. Ukuran pertama kali tertangkap (Lc) ikan cakalang oleh huhate adalah 41,7 cmFL. Exploitation of skipjack tuna resources in the Banda Sea have lasted long. Currently skipjack tuna resources have been showing signs of over fishing. Indications were, among others, characterized by a decrease in the catch and the size of the individual, changes in the composition of the catch and the trend of increasing proportions of several types of small fish. Length frequency data collected from March until December 2007 amounted 4,293. Length and weight measurements to determine the length and weight relationship of fish conducted in March, May, July, and December 2007 with a total sample was 296. This paper presents information about the distribution of length and weight, length and weight relationship and the length at first capture (Lc) caught by pole and liner operating in theBanda Sea. The analysis showed that the skipjack tuna has a long range between 30-78 cmFL and weight range between 600-4300 g. Regression analysis of length and weight relationship equation was W=0.0485 L2.751, R2=0.9427 with regression coefficient (r)=0.9709, and slope value (b)=2.751. Result show that the growth pattern of skipjack tuna was negative allometric. The length at first captured (Lc) of skipjack was 41.7 cmFL.

scholarly journals Population dynamics of skipjack tuna (Katsuwonus pelamis) in the northern and western waters of Aceh

2021 ◽  
Vol 674 (1) ◽  
pp. 012089
Author(s):  
A Damora ◽  
F Fazilla ◽  
A W Perdana ◽  
A Rahmah ◽  
R M Aprilla ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Skipjack Tuna ◽  
Katsuwonus Pelamis

Survey and control of small mammal populations on two hardwood plantations in southern Ontario

1974 ◽  
Vol 50 (5) ◽  
pp. 181-185 ◽  
Author(s):  
Andrew Radvanyi
Keyword(s):  
Small Mammal ◽  
Late Summer ◽  
Control Measures ◽  
Effective Control ◽  
Southern Ontario ◽  
Live Trapping ◽  
Surrounding Areas ◽  
And Control ◽  
Rodent Populations ◽  
Ingredient Cost

Live trapping and tagging methods were employed to assess small mammal populations within two hardwood plantations in southern Ontario. Excessive girdling damage in past years to young planted trees necessitated an evaluation of rodent populations and development of effective control measures. The application of an anticoagulant rodenticide to oat groats bait broadcast over the study area at an ingredient cost of approximately three dollars per acre virtually wiped out the small mammals. Reinvasion from surrounding areas was, however, fairly rapid, particularly during late summer. Further research on longer term control measures using poisoned bait feeder stations is recommended.

Stock status and current tendencies in the population dynamics of commercial fishes of Pskov-Chudskoe water body

2013 ◽  
Vol 53 (1) ◽  
pp. 28-40 ◽  
Author(s):  
A. E. Bobyrev ◽  
E. A. Kriksunov ◽  
N. N. Murzov ◽  
M. B. Danilov ◽  
M. M. Mel’nik ◽  
...  
Keyword(s):  
Population Dynamics ◽  
Water Body ◽  
Stock Status

scholarly journals Cognitive dysfunction in children with sleep disorders

2004 ◽  
Vol 62 (2a) ◽  
pp. 212-216 ◽  
Author(s):  
Luciane Bizari Coin de Carvalho ◽  
Lucila Bizari Fernandes do Prado ◽  
Luciana Silva ◽  
Marilaine Medeiros de Almeida ◽  
Tatiana Almeida e Silva ◽  
...  
Keyword(s):  
Sleep Disorders ◽  
Cognitive Dysfunction ◽  
Screening Test ◽  
Total Sample ◽  
Control Group ◽  
Lower Prevalence ◽  
Control Groups ◽  
Similar Frequency ◽  
Visual Motor ◽  
And Control

Sleep is basic for physical and cognitive development and some studies have suggested that there may be an association between sleep disorders (SD) and cognitive dysfunction (CD) in children. Little is known, however, about SD and cognition in 7-10-year-old children, a fact that motivated the present study. METHOD: We applied an SD questionnaire in 1180 children, 547 with SD and 633 without SD (CG), to assess cognition with a screening test (Bender Visual Motor Gestalt Test - BT). RESULTS: We observed a similar frequency of CD in the children with SD (39%) and that ot the CG (40%). The 8-year-old children with SD presented a lower prevalence of CD than the CG (SD=6%, n=6; CG=13%, n=16; p=0.04). CONCLUSION: The frequency of children with CD was equal in the study and control groups when considering the total sample (7- to 10-year-old children). In contrast to our expectations, the SD group of 8-year-old children presented a lower frequency of CD than the control group.

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