Impact of a El-Nino Southern Oscillation (ENSO) to fluctuation of skipjack catch production in Southern East Java

Abstract

There are challenges in utilizing marine resources in Indonesia and one of them is environmental changes caused by ENSO phenomenon. Skipjack catch production in southern Malang has been fluctuated since this phenomenon occurred. Lack of information about ENSO phenomenon among fisherman has led to under-utilized fish production which resulting in less Skipjack caught during ENSO. The purpose of this study was to analyze the impact of ENSO phenomenon to catch production of Skipjack. The method used in this study was by gathering secondary data of catch production of skipjack and seawater surface temperature from satellite image of level 3 AQUA-MODIS with 4 km resolution during ENSO which occurred between 2014-2016. The result of this study showed that seawater surface temperature on southern Malang was 24,825-32,055°C. Southern Oscillation Index (SOI) showed strong El-Nino occurred between May-October 2015, La-Nina occurred between June-September 2016. Analysis data showed that there was less significant influence of ENSO and seawater surface temperature which led to other variables may contribute into ENSO. During El-Nino 2015 there was sharp increasing of skipjack catch production in southern Malang and the major cause was colder seawater surface temperature, this indicating that the seawater was rich of nutrients. Supporting by optimum water condition during El-Nino that location was rich of food resources which suits some of big pelagic fishes, particularly skipjack.