Problem Formulation Studies On Fish BehaviourIn Relation Net Transparency of Millennium Gillnet Operation In Bondet Waters, Cirebon

water. They further inferred that the visibility of nets depends on both the water colour and the colour of the seabed. Cui et al. 1991 used the light intensity thresholds as an indicator of the fishing power of different coloured nets by comparing mackerel Scomber scrombus behaviour towards different coloured twine. Considerable differences in colour selection thresholds observed for both a thin monofile thread and a thicker multifilament thread. As new adopted gear, analysing a factor affecting the effectiveness on catch, in this case the net transparency is considered necessary. In order to analyse the net transparency; in relation of fish as catch target, some approaches should be conducted. The study of behaviour often becomes the best way on analysing these problems e.g. Wardle et al. 1991, Cui et al. 1991. Knowledge of fish behaviour, in relation to captures, can be acquired in different ways. Laboratory studies informs that the fish behaviour patterns towards the gear or representations of gear-related stimuli can be described, and general behaviour relevant to the fish capture process such as the swimming capacities of different species, can be studied Ferno and Olsen, 1994. Meanwhile, as first step to understand the catch performance of millennium gillnet, the study of capture process is needed. This become necessary since the information regarding this gillnet, which it was used from the first time until recent years is still limited. The capture process of gillnet can be determine according to the ways of fish being retained in the net. The fish can be captured by being gilled, wedged, snagged and entangled Hovgard and Lassen, 2000. For that reason, some studies are needed to understand the effect of transparency on fish behaviour towards net panel. Not just the effect of transparency, some studies are also needed to obtain some information regarding the capture process of millennium gillnet as the way to understand the catch performance of this net. 3

1.3 Objectives

The research objectives are: 1 To investigate the effects of the net transparency on fish behaviour in relation to the net panel of millennium gillnet. 2 To obtain the information on catch composition and capture process of millennium gillnet.

1.4 Benefits

The research result can be beneficiary for understanding millennium gillnet in Cirebon, regarding: 1 The effects of transparency on the fish behaviour in relation to the net panel of millennium gillnet. 2 The catch composition and capture process of millennium gillnet.

1.5 Hypothesis

Hypothesis of this research is the net transparency affects the behaviour of fish in relation to net panel of millennium gillnet.

1.6 Conceptual Framework

The millennium gillnet effectiveness in Cirebon is believed to be affected by the net colour or transparency and fish performance Figure 1. Two methods of investigation were used to understand both factors. The transparency factor was investigated in the experiment of fish behaviour towards contrast colour panel and specific white panel and data were analyzed using Anova. Meanwhile, the fish performance factor was investigated by experimental fishing operations to understand the capture process and catch composition. A descriptive analysis of catch composition was used to analyse the data. The output of these studies were recommendation on the effective and efficient colour of millennium gillnet and information on catch composition and capture process. 4 Millennium gillnet effectiveness in Cirebon Affected by colour transparency Affected by fish performance Investigated through fish behaviour in relation to net panel Investigated by fishing experiments operations Fish behaviour on contrast color Fish behaviour on specific white panel Old white net, new white net and black painted Old white net, new white net and white painted Descriptive analysis through percentage of catch composition Capture process and catch composition One Way Anova Two Way Anova • Recommendation the effective and efficient colour of millennium gillnet • • Information of catch composition and capture process Figure 1. The systematic diagram of this research 5