APORTE AL SISTEMA NACIONAL DE ÁREAS PROTEGIDAS

From the perspective of the vessel, the major variable in relation to fishing operations is the number of the trips, as it indicates the fishing effort. Figure 4.3 presents the seasonal index of the fishing trip for the four studied vessels. According to the type of fish target, pelagic fishing conducted by PD and LF vessels peaks between August and October, whilst demersal fishing conducted by HL and TN vessels peaks twice roughly between October-November and February-March.

Regarding the weather conditions described in Section 3.4.5, it can be noted that most of fishing operations are conducted during the west monsoon period (October-March). However, when the weather becomes rough between December-January, the vessels reduce their fishing trips for safety reasons. A further reduction occurs from April, when the east monsoon blows, until July, when the weather deteriorates again. This happens to all the studied vessels, except for the LF vessel, which displays increasing fishing activities from April to August.

Figure 4.3 Seasonal indices of the studied vessels (using fishing trip variable)

Apart from the weather conditions, fishing seasons generally follow the fish abundance. A study conducted by Wiyono (2001) and Ilhamdi et al. (2016), reveals that the abundance of small pelagic fish such as ponyfish, little tuna and sardines in Palabuhanratu Bay and other southern coastal areas of Java island peaked between June and November. In contrast, hairtail fish, lobster and shrimp, which are caught by HL and TN vessels, are typically plentiful from October-April (Boesono et al., 2011; Harjanti et al., 2012), and furthermore, according to Jayanto et al. (2013), shrimp might also peak between July- September. The fish seasons do not occur in the same months every year and the period might change because of various environmental factors, such as climate change and ecosystem dynamics (Brönmark et al., 2008; Brander, 2010; Bell et al., 2013). However, it will be around the aforementioned ranges.

Using the seasonal index, the fishing patterns throughout the year have been predicted. Furthermore, fishers were asked to identify the fishing seasons according to their experiences. The result was used to validate the pattern obtained from the calculation, as shown in Table 4.1.

Table 4.1 Comparison of the fishing trip pattern between the seasonal index calculation and fishers’ knowledge

The comparison confirms that in general, both versions reveal a matching pattern, and most importantly, the period and length of each season resulting from the calculation correspond to the fishers’ knowledge. However, it should be noted that some dissimilarities appear due to different interpretations and the fact that the fishing seasons are changing over time. For example, respondents from PD vessels claimed that July- September is the typical fishing peak season, as described in the following statements:

“The fish are typically abundant starting from June onward, but now even though it is already September, it is just average” (Respondent F.1.2.1)

“The peak season is typically from July to September but this year we did more fishing in September and October, even though we are about facing the west monsoon” (Respondent O.1.0.1)

In fact, the calculation result shows that it occurs between September and October. Therefore, despite of some dissimilarities between both versions, the fishing pattern resulted from the calculation was subsequently used for further modelling.

Besides the fishing trip, other variables, such as catch/trip, fish price/trip and fuel/trip also change seasonally. By using the CMA method, the seasonal index for other variables is presented in Figure 4.4. Subsequently, it was interpreted into three seasons. The result is presented in Table 4.2.

Both illustration reveal that each variable has a different trend, which is not necessarily in line with other variables. For example, in the PD vessel, when the catches and the number of trips are low in June, fuel use peaks because the vessels spend more time at sea. Conversely, the LF vessel carries roughly the same amount of fuel throughout the year due to less varying route. Regarding the market situation, fish prices for PD and TN

Fishing vessel Fishing season Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Calculation Mod Mod Mod Low Low Low Mod Mod Peak Peak Mod Low Fishers' version Low Low Low Mod Mod Mod Peak Peak Peak Mod Mod Low Calculation Mod Peak Peak Low Low Low Mod Mod Mod Peak Peak Peak Fishers' version Peak Peak Mod Mod Low Low Low Mod Mod Mod Peak Peak Calculation Mod Peak Peak Peak Mod Low Low Low Mod Peak Mod Mod Fishers' version Low Low Mod Peak Peak Mod Low Mod Mod Peak Peak Low Calculation Low Low Mod Low Mod Mod Peak Peak Peak Peak Mod Low Fishers' version Low Low Low Mod Mod Mod Mod Peak Peak Peak Mod Low PD vessel

TN vessel HL vessel LF vessel

Figure 4.4 Seasonal index of the studied vessels

Table 4.2 Seasonal fishing patterns of the studied vessels

vessels are fluctuating, whilst for HL and LF vessels the price ordinarily remains constant regardless of the seasons. Most importantly, the weight of catch/trip does not necessarily peak when the trip number is at its highest point. Ignoring the fluctuation of each variable might lead to inaccuracy, therefore, following the pattern obtained from the seasonal index is the most accurate way to model the existing practice.