Distribution and Habitat Characteristics of Shrimp Juvenile in Segara Anakan Lagoon

Shrimp as fishery resources that live in Segara Anakan lagoon is known as a high economic species. So the existence and habitat from larvae to adult more suistable with furthermore to maintain the survival of shrimp The purpose of this study is to determine the characteristics of shrimp juvenile habitat in Segara Anakan lagoon. Sampling is done 3 times (June, August and October 2013), with 9 stations Observation station. Shrimp and fish resource data were collected through self-capture experiments using beam trawl fishing equipment. Beam trawling made of iron frame with a width of 1.0 m, height of 0.3 m and a net length of 2 m. while the jaring is made of webbing material (supernet d/12) and diameter of mesh 10 mm. The fishing gear is pulled at 2 knots for 10 minutes. The results explaining: 1. Species distribution each station, 2. Number of abundant species each station and than habitat characteristic each station that the abundance of shrimp based on the amount in Segara Anakan lagoon was dominated by Metapenaeus elegans (205-8723 ind./1000 m 2 ), whereas the abundance of M. ensis, F merguensis, P. semisulcatus and P. monodon relatively low had the same habitat , ie waters with high fertility and relatively low salinity, relatively high pH. Found in Motean observation station, Muara Dua, Kleces and Majingklak. Harpiosquilla annandalei (0-330 ind/1000 m 2 ), P. monodon (0-238 ind/1000 m 2 ), and Acetes sp (0.1-5.196 ind/1000 m 2 ) sounded a lot of water habitat that contain BOT and high zooplankton abundance. Thus the shrimp Harpiosquilla annandalei, P. monodon, and Acetes sp are found in Tritih observation stations, and are quite commonly found in Kleces observation stations.


Introduction
stated that the wealth of Segara Anakan fishery resources is characterized by an abundance of various unique and potential biota including 60 species of fish, 19 species of shrimp. The types of crustaceans are dominated by White shrimp species (Fenneropenaeus merguiensis), Jerbung shrimp (F. indicus) and Shrimp krosok or fingers (Metapenaeus elegans), and several other important species. Where in the phase of his life has two places in his life cycle that in sea water and brackish water. Penaeid shrimp have a worldwide distribution in tropical and sub-tropical seas, and are the most important biota in estuarine and coastal habitats (de Abreu, Daniela Carvalho, 2017). At least 19 species of 7 genera are reported from the western ocean region (de Freitas, 2011).
Shrimp usually live in relatively shallow waters with sandy bottom and have high turbidity (Fulanda et al., 2011;Munga et al., 2012). In the larval phase the species prefers the estuary of the river and when entering the juvenile phase moves from the estuary to the sea, where they grow until they mature and lay eggs (Anand, et. al. 2014;Kunze, et.al. 2014 ). These environmental variables can cause differences in the composition of penaeid shrimp species (Anand, et. al. 2014).
Pursuant to that matter hence this research aim to know distribution and characteristic of shrimp juvenile habitat at Segara Anakan lagoon by using environment variable. It is necessary to the focusing to distribution of shrimp as the research fisheries

Materials and tools
Some equipment, materials and methods used in the observation of the environmental quality of the lagoon waters are presented in Figure 1. Data of shrimp resource collected throug The materials and methods used in observing the environmental quality of lagoon waters are presented in Table 1. Shrimps were collected of using beam trawl. Beam made of iron with width 1.0 m, height 0.3 m and net length of 2 m. while the net is made of webbing (supernet d / 12) and diameter of mesh 10 mm. The fishing gear is pulled at 2 knots for 10 minutes. The position using GPS (Garmin). Water depth is shrimp sampling results were selected and identified and included in plastic bags and preserved in 10% formalin and labeled.

Data analysis
Abundance of juvenile shrimp was determined using swept area method, with the formula (modified APHA, 2005): Where: N = abundance of juvenile shrimp (ind./1000 m 2 ); n = number of juvenile (Ind.); l = width of beam trawl (m); s = length of path covered (m).
The waters quality method proposed by APHA (2005), Davis (1955), and Boyd (1990) (Appendix 1). Phytoplankton by microscope. The calculated based on phytoplankton abundance "Lackey Drop Microtransett Counting" (APHA, 2005) by the formula, where, N f = abundance of phytoplankton (ind./l), F f = correction factor, n f = number of phytoplankton (ind.), A f = area of glass cover (mm 2 ), a f = wide field of view (mm 2 ), L f = number of visual field, V 1 = volume (ml), V 2 = volume filtered (ml), dan V f = volume taken (l). with plankton nets, while phytoplankton biomass measurements by taking 500 ml of water sample and MgCO 3 to inhibit photosynthesis and stored in dark bottles, chlorophyll content measurements subsequently using -trichromatic". Calculation of chlorophyll a follow equation (APHA, 2005;Stirling, 1985) as calculated based on follows: Variables observed were physicochemical and biological water, such as temperature, depth, water flow, transparancy, texture of the substrate, electrical conductivity, pH, dissolved oxygen, carbon dioxide, alkalinity, organic matter and macrozoobenthos. The data obtained were analyzed using Principal Component Analysis (PCA) with the assumption that changes of stochastic water quality. Factors of human activity and the environment is considered as a random effect that determine changes in water quality (Schoener, 1987). Technical of PCA used in the study of the relationship between ecological phenomena, and its main purpose is synthesizing data variation then interpret multidimensional matrix, meaning that complex ecological data can be synthesized into a simple (Legendre & Legendre, 1983 Refractometer, directly at the waters 6. Dissolved oxygen mg/L Using the Winkler titration, directly at the waters 7. Carbon dioxide mg/L Titration using EDTA Na, directly at the waters 8. Nitrate mg/L Brucine Sulfate, Spectrophotometer, in the lab 9. Nitrite mg/L Alfa-nastilamin, Spectrophotometer, in the lab 10. Total Organic Matters mg/L Titration using KMnO 4 , in the lab 11. Chlorophyll-a mg/m Plankton net with size of mouth of net 0.30 m, mess size 60 lm (for phytoplankton) and 0.45 m; 150 l21m (for zooplankton).,

Result
The range water brightness observations in Segara Anakan lagoon was obtained from 25-140 cm, and in Tritih and Muara Dua (30-60 cm) ( Table 2). The dissolved oxygen content ranges from 1.31-6.02 mg / L with the lowest dissolved oxygen was obtained in Donan (1.7-3.67 mg / L), and was highest in Kleces (3.14-5.37 mg / L), while the salinity was between 0.2-13.7 ‰ where the lowest salinity was in Muara Dua (average 0.5 ‰ with range 0.3-0.6 ‰), and highest in Plawangan (average 5.7 ‰ with a range of 0.2-13.7 ‰).
Nutrient content in Segara Anakan lagoon waters, ie N-NO 3 , N-NH 4 , and P-PO 4 ranged between 0.292-2.871 mg/L, 0.021-0.188 mg/L, and 0.292-2.871 mg/L respectively. the lowest nitrate content is Tritih with a range of 0.362-1.  Principal Component Analysis gives 100% total variant (8 factors). Figure 2 shows the relationship between the variance for each factor value, and Factor 4 is the turning point of the graph where the total number of cumulative variance values is 77.82%. This suggests that the analysis of this key component provides an optimal picture of the diversity of data from factor 1 to factor 4, and addition of factor 5 and subsequently lacks a significant picture of the relationship between shrimp adolescents, the environment and observation stations. This condition means that this analysis only able to explain the relationship between juvenile shrimp, environment and observation station equal to 77,82%.  Tritih is an observation station in the eastern part of the upper lagoon of Segara Anakan, and in this area is found Fenneropenaeus indicus, and Penaeus monodon, and quite abundantly found Harpiosquilla ammamdalei, Acetes sp and F. merguensis. In addition, the station has good forest characteristics, so that it have high the content of Total Organic Material (BOT), salinity and the abundance of zooplankton.
Trith also low ocontains of P-PO 4 , N-NO 3 , O 2 and chlorophyll-a (Figure 2). This is due Tritih location is relatively close to the waters of the sea, so that the organic material has not had much time to decompose into nutrients already brought tidal currents toward the sea. Donan, Kebun sayur and Sapuregel, these three areas have many similarities, these areas have high organic, salinity, abundance of zooplankton and brightness. In addition, this area has low contents of P-PO 4 , O 2 , N-NO 3 , N-NH 4 and chlorophyll-a. When compared with Tritih, the third position of the area is closer to the sea waters, so the process in the nutrient cycle is the same as Tritih. The difference with Tritih, the three areas are juvenile shrimp more dominated by Harpiosquilla ammamdalei and Acetes sp.
Motean located in the center of the Segara Anakan lagoon, where this area is found many Metapenaeus elegan, Macrobrachium rosenbergii and Penaeus semisulcatus. It is presumed that this area has unique characteristics, among others: the forest condition of the mangrove is quite good with high content of N-NO3, O2, and chlorophyll-a; N-NH4 and P-PO4 high enough. In addition, this area has a low content of BOT.
Muara Dua is the middle and upper waters of the lagoon, in this area is found quite abundantly of Macrobrachium rosenbergii and Penaeus semisulcatus. Muara Dua has the characteristics of the waters with good mangrove forest, so this area has high content of N-NO 3 , O 2 , and chlorophyll-a; N-NH 4 and P-PO 4 are high enough. In addition, this area have low content of BOT and salinity.
Kleces and Majingklak are located in the western region of the lagoon, and in this area found many M. elegant, and quite abundantly of found of shrimp Macrobrachium rosenbergii, and Penaeus semisulcatus. Characteristics of these waters include good it mangrove forest conditions with high content of N-NO 3 , O 2 , and chlorophyll-a; N-NH 4 and P-PO 4 are high enough. And the other, Plawangan is area the entrance of sea water in the western lagoon, in this area found many shrimp F. merguensis; and quite a lot found of F. indicus and Penaeus monodon. Plawangan have the characteristics of the waters, among others, brightness, and high salinity, and high enough BOT content. This area also has a low N-NH4, as well as low content for chlorophyll-a and abundance of zooplankton.  (Dudley , 2000). The results of Sumiono's research (2009) showed that the composition of shrimp caught by apong in Donan village was rebon shrimp (44%), M. elegans (31%), dragon shrimp (19%) and F. merguensis (6%). While for the village of Karangtalun the composition of the shrimp catch is M. elegans (61%), F. merguensis (30%), Parapenaeopsis sculptilis (4%), Alpheidae (3%) and Metapenaeopsis sculptilis (2%) (Sumiono, 2009). Shrimps that have high economic value are slightly different from those in Pemangkat, West Kalimantan, such as Penaeus merguiensis, P. monodon, P. semisulcatus, P. esculentus, P. latisulcatus, Metapenaeus ensis and M. endeavouri (Wedjatmiko et al. 2011).

Discussion
The shrimp habitat varies greatly depending on the type and requirements of life (comfort) for each phase of its life cycle. The larvae are planktonic and drift away from the spawning areas to the bays and estuaries of the river. the postlarvae then migrate to the estuary, which is very rich in nutrients and low salinity.
These water shrimp grow and sometimes migrate again to the open waters where they mature (Ruas, et al., 2014). Juvenile found coastal waters and lagoon (Anand, et.al., 2014). Adult shrimp are benthic animals that mainly live on the ocean floor. Preferred habitats are soft base types, usually composed of a mixture of mud and sand.
In general, shrimp are caught in large quantities in shallow waters, especially in areas of the river mouth. Penaeid shrimp happy to live in areas where there is a mixing of river water and seawater, because here is widely available food and nutrients needed shrimp. Mangrove forests are areas where seawater and freshwater are mixed, and the forests are able to provide continuous food and serve as a shelter (Pratiwi, 2008).
Shrimps become adults and lay eggs only in marine water habitats. Females are able to spawn 50,000 to 1 million eggs, which will hatch after 24 hours into larvae (nauplius). Nauplius then morphed into the second phase the zoea (plural zoea). Zoea ate wild algae. After a few days morphed into mysis (mysis plural). Mysis eats algae and zooplankton. After three to four days then they metamorphosed the last time entering the pascalarva stage: young shrimp that already possessed the characteristics of an adult animal. The whole process takes about 12 days from the first hatch. In the wild, the postlarvae then migrate to the estuary, which is very rich in nutrients and low salinity (Ruas et al., 1990).
Shrimp Krosok (Metapenaeus elegans), Pacet (Penaeus semisulcatus) and Galah (Macrobrachium rosenbergii) have similarly favored habitats, ie waters with high fertility. These waters are characterized by high levels of chlorophyll-a, N-NO 3 , N-NH 4 and O 2 ; and low BOD content. The difference Shrimp Krosok and pacet like waters that have content of P-PO 4 and N-NH 4 is high enough to high. While this prawns tend to choose waters with NO 3 content and high chlorofill-a content, and low salinity. Thus, the observation stations that are mostly found in the shrimp Krosok, Pacet and Galah are Motean ( . White Shrimp (F. merguensis) enjoys waters having high salinity, brightness, and P-PO 4 , as well as low abundance of zooplankton, low enough N-NH 4 and BOT chlorophylls. Therefore, this white shrimp is found in many observation stations Plawangan (176 ind./1000 m 2 ). F. merguiensis has a high adaptability to all basic types of waters, but prefers sandy loam sand water bases (Pratiwi, 2008). Based on his research, the food of some types of Penaeus shrimp such as: F. merguiensis is omnivorous, eating what is available in nature. In addition, F. merguiensis mysis levels ate larvae from balanus, copepoda, and polychaeta; and at post larval levels in addition to microorganisms, also ate phytoplankton and green algae (Pratiwi, 2008).
Ronggeng shrimp (Harpiosquilla annandalei), Tepus (P. monodon), Jerbung (Fenneropenaeus indicus) and Rebon (Acetes sp) have many similarities in favorable aquatic habitats, ie waters with high content for BOT and abundance of zooplankton with low for P-PO 4 and brightness, but Harpiosquilla annandalei and Acetes sp also chose waters with brightness, high BOT content and zooplankton abundance, and high salinity. P. monodon and Fenneropenaeus indicus in addition to selecting these waters brightness, BOT content and abundance of zooplankton is also high in waters, and low N-NH 4 content. Thus, Ronggeng, Tepus, Jerbung and Rebon shrimp were found in the Tritih observation station, and found quite a lot in the Kleces observation station (Poernomo, 1968in Pratiwi, 2008, commonly post larva "tiger prawns (Penaeus monodon) found along the sloping coastline fluctuating tides, and small rivers and sloping bases , mud or small rocky rocks (clam shells). The optimum salinity for growth of tiger shrimp and white shrimp was 10 -25 ppt (Antony and Harikrishna, 2015, Samocha, et.al, ) and 27 -31 ppt (Kannan D, et.al, 2015) respectively, while salinity in the study area ranged from 31 to 35 ppt, such conditions inhibit the normal growth of shrimp. This is because tiger prawns can grow better at lower salinity, where the environment allows more energy transformation for the process of meat formation and less energy is used for osmoregulation to maintain fluid pressure balance with the environment (Poernomo, 1978in Pratiwi, 2008.
Kebun Sayur is the entrance of sea water to the lagoon from the East. This area has the characteristics of deep and wide waters, so cycles the entry of sea water is very smooth. As a result the tidal currents are relatively fast for the eastern lagoon area, thus organic matter has not yet fully decomposed into nutrients already wasted into the sea. The positive impact of the rate of silting this lagoon waters is lower than the western lagoon.

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Omni-Akuatika Vol. 14 No. 1 May 2018 : 87 -95 Muara Dua, Motean, Kleces and Majingklak have very similar water characteristics. The difference is the distance of each observation station to the sea. The furthest position to the sea is Muara Dua station, because the entrance of the sea water circulation is Plawangan Barat. While Plawangan Barat entrance is a very narrow and shallow, so tidal current is relatively slow. These conditions cause the existing organic material to decompose quite a lot into nutrients, such as: N-NO 3 , N-NH 4 and P-PO 4 . This is indirectly causing the Laguna Segara Anakan region of the West is more fertile than the eastern part.

Conclusion
The abundance of shrimp based on both quantity and weight in the Segara Anakan lagoon is dominated by Metapenaeus elegans 723 ind./1000 m 2 ), whereas the abundance of M. ensis, F merguensis, P. semisulcatus and P. monodon are relatively low and having the same habitat, i.e. waters with high fertility and relatively low salinity, relatively high pH.