No abstract

The swimming layer is one of the important factors to get maximum catches, especially on tuna longline effort. The vertical abundance of the albacore tuna was investigated based on catch data and 3-DINDESO Ocean Model data, such as sub-surface conditions of sea water potential temperature (Temp), salinity (Sal) and mass concentration of diatoms and flagellates expressed as chlorophyll (Chl) in the Eastern Indian Ocean period 2014-2015. Combining he statistical method of generalized additive model (GAM) was performed to analysis in this study. There were seven GAM models that generated with the number of ALB vertical abundance as a response variable, and Temp, Sal, and Chl as predictor variables. Sal has highly significant (P < 0.001) while Chl and Temp significant (P < 0.01) to ALB vertical abundance. Deduced from GAMs, indicated that a negative effect of Sal on the number of ALB was observed at salinity >34.52 psu. There was a positive effect of salinity on the number of ALB, which was from 34.30 to 34.47 psu and Chl showed a positive effect of this variable on the number of ALB caught occurred between 0.01 mg/m3 and 0.12 mg/m3 in the region of high confidence level where negative effect on > 0.13 mg/m3. While ALB catches abundance varied in the temperature range with the highest frequency at 24.0-24.9 °C. Sal was the most important environmental variable to the number of ALB vertically caught, followed by Chl and Temp.

Perikanan pelagis di perairan Selat Bali telah diusahakan sejak lama. Data runtut tahun hasil tangkapan yang didaratkan cenderung berfluktuasi. Kajian ini bertujuan untuk mengetahui kondisi spasial dan temporal karakteristik oseanografi, terkait dengan dengan dinamika perikanan pelagis di Selat Bali. Data parameter oseanografi meliputi suhu permukaan laut (SPL) dan klorofill-a (chl-a) yang diperoleh dari citra satelit penginderaan jauh Aqua/Terra MODIS, sedangkan data sumberdaya perikanan pelagis berupa hasil tangkapan/satuan upaya (Catch per Unit Effort, CPUE) ikan pelagis diperoleh dari Tempat Pendaratan Ikan (TPI) Pengambengan, Jembrana - Bali pada periode Januari 2007 hingga Desember 2015. Uji statistik regresi linear berganda digunakan untuk mengetahui pengaruh parameter oseanografi terhadap kondisi perubahan sumberdaya perikanan pelagis. Sebaran spasial SPL menunjukkan bahwa pada Mei hingga November suhu permukaan laut cenderung rendah serta tidak ada perbedaan yang signifikan antara suhu di perairan pantai dan di laut lepas. Secara temporal terlihat bahwa suhu terendah terjadi pada musim timur yaitu pada Agustus 2007. Sebaran spasial chl-a menunjukkan bahwa peningkatan konsentrasi chl-a dimulai dari Mei hingga Oktober serta terdapat perbedaan yang signifikan antara chl-a perairan pantai dan laut lepas. Secara temporal terlihat bahwa konsentrasi chl-a tertinggi terjadi pada Oktober 2015. Faktor iklim yang merupakan faktor eksternal memberikan pengaruh terhadap perubahan konsentrasi chl-a pada lokasi penelitian. Faktor iklim tersebut adalah kecepatan angin dan kejadian El-Nino. Hasil analisis statistik menunjukkan bahwa perubahan parameter SPL dan chl-a secara bersama-sama berpengaruh signifikan terhadap perubahan CPUE ikan pelagis, namun secara parsial parameter chl-a memberikan pengaruh yang lebih signifikan dibandingkan dengan parameter SPL.Pelagic fisheries around Bali Strait have been exploited since decades. Based on monthly and annual landing data, fish production around Bali strait are very fluctuated. This study aims to determine the spatial and temporal conditions of oceanographic characteristics and how they relate to the dynamics of pelagic fisheries in the Bali Strait. The oceanographic parameter data consist of sea surface temperature (SST) and chlorophyll-a (chl-a) that obtained from Aqua / Terra MODIS remote sensing satellite imagery, while the dynamics of pelagic fish resource data indicated by Catch per Unit Effort (CPUE) derrived from landing place (TPI) Pengambengan, Jembrana - Bali in the period January 2007 to December 2015. Multiple linear regression analysis were applied to determine the effect of oceanographic parameters on the changing conditions of pelagic fishery resources. Spatial distribution of SPL indicates that in May to November sea surface temperature tends to be low and there is no significant difference between the temperature in coastal waters and on high seas. The temporal distribution shows that the lowest temperature occurred during the southeast monsoon in August 2007. The spatial distribution of chl-a showed that the chl-a concentration starts to increase from May to October and there were significant differences between chl-a coastal waters and high seas. The temporal distribution shows that the highest chl-a concentration occurred in October 2015. Climate factor which is an external factor has an effect on the change of chl-a concentration at the research location. Climatic factors are wind speed and El-Nino events. The result of the statistical analysis shows that the change of SPL and chl-a parameters together significantly influence on the CPUE of pelagic fish, but partially chl-a parameter gives highly significant effect than SST parameter.

As a dominant small pelagic fishery in Bali Strait waters, significant decrease of sardine (lemuru) production was bothering fisheries industries, particularly in Muncar and Pengambengan District in East Java and Bali province.  Besides of over exploitation, changing environment condition such as temperature, salinity and thermocline depth, indicated the affect on decreasing of sardine production.  The interaction among environment variabels, food source availability (Chl-a) and anthropogenic pressure (fishing effort) generate the number of sardine abundance showed by CPUE (Catch per Unit Effort) value that determined sardine production. The current research aims to analyze the simultant impact of changing environment, food availability and antropogenic pressure on sardine CPUE.   Field research was conducted in Bali Strait where primary and secondary fisheries data were gathered at Muncar Fishing Port of Banyuwangi District East Java Province and Pengambengan Fishing Port of Jembrana District Bali Province.  Oceanography data such as temperature, salinity, and chlorophyll-a profile were collected from INDESO Model. Data analysis was done by time series analysis of each variabels such as CPUE, SST and SSTA, thermocline depth, chl-a and also the number of trip.  Partially analysis of those variabels was done by overlayed one another, and principal component analysis determined to analyze the effect of all those varibales simultaneously on sardine CPUE.  Results show that there were an influenced of regional climate phenomenon on the dynamic of environment condition of Bali Strait waters, particularly IOD (Indian Ocean Dipole).  The CPUE of sardine was determined by the interaction of environment variabels (SST/SSTA, salinity, thermocline depth), food source availabity (Chl-a) and antropogenic pressure (fishing trip) simultaneously, however SSTA gives a significant negative correlation on CPUE.  Regional climate phenomenon might cause an extreme condition in Bali strait waters leading to unstable environment for sardine habitat.  Drastically changing habitat condition occured under influenced of extreme condition would lead to disruption of sardine CPUE.

<p><em>The research was to know the influence of the supplementation lemuru fish oil and L-carnitine on the local male ducks’ performance. The cattle used were 96 local male ducks aged 10 days. Research materials were corn, bran, concentrate 144, lemuru fish oil, and L-carnitine. The research design used was Complete Random Design with 3 treatments and 8 repetitions; each repetition contained 4 local male ducks. The treatment consisted of ration control P0 = corn, barn, concentrate and mineral; P1 = corn, barn, mineral and 4% lemuru fish oil; P2 = corn, barn, concentrate, mineral, 4% lemuru fish oil and 30 ppm L-carnitine. The investigated modifiers were feed consumption, feed conversion, daily weight increase and Income Over Feed Cost value. Data feed consumption, daily weight increase, feed conversion was analyzed using variance analysis. If there were a concrete influence, further analysis should be conducted using orthogonal contrast. Results showed that the supplementation of lemuru fish oil and L-carnitine had a very significant influence (P&lt;0.01) on feed consumption, daily weight increase and feed conversion. Further test results orthogonal contrast showed that the supplementation of lemuru fish oil and L-carnitine could decrease feed consumption, feed conversion and increase daily weight rate (P&lt;0.01) if compared control. Result Income Over Feed Cost showed that treatment with add lemuru fish oil and L-carnitine produced Income Over Feed Cost value higher if compared control. Based on the results of the research, it could be concluded that the supplementation of 4% lemuru fish oil and 30 ppm L-carnitine in ration could decrease feed consumption and feed conversion, increase daily weight rate, and the IOFC of local male ducks.</em></p>