Diadema setosum, a Red Sea migrant, was first identified on the shores of the KaÅŸ Peninsula in the Mediterranean. Approximately a year after this observation, the same species was reported for the second time from Konyaaltı Beach in Antalya Bay. This sea urchin rapidly multiplied and expanded its distribution along the coasts of the Mediterranean and Aegean Seas, reaching as far as the Marmara Sea. Some individuals of this sea urchin, which expanded distribution to coastal areas posing a risk to swimmers, were observed to start dying in the summer months of 2022. Scuba diving surveys were conducted in five different areas with rocky and stony seabed structures in the Gulf of Antalya during the winter season (Cliffs, Konyaaltı Beach, Sıçan Island surroundings, Çaltıcak region, and Kemer Ağva Cape), and it was determined that 99% of the D. setosum population had died in February and March. No living individuals were encountered during scuba diving surveys conducted in the same stations in April and May. In conclusion; mass mortalities have occurred in the D. setosum population in the rocky areas of the Gulf of Antalya, including the cliffs, Konyaaltı beach, Sıçan island surroundings, Caltıcak region, and Kemer Ağva Cape. This study presents the first report on matter.Keywords: Diadema setosum; Gulf of Antalya; Sea urchin.

Cengklik Reservoir is one of the water and waterfront tourism destinations in the Boyolali Regency which has an area of 327,44 ha. The condition of Cengklik Reservoir is currently undergoing revitalization and tourism development. The purpose of this study was to analyse the suitability of reservoir waters as a tourist attraction based on the Tourism Suitability Index, to determine the perceptions of tourists potential in the reservoir, and community perceptions of tourism development in the reservoir. The research was conducted in March - April 2023. The research methods used a case study with quantitative analysis to calculate the value of the Tourism Suitability Index and qualitative analysis to determine the perception of tourism potential from 30 tourist respondents and tourism development from 30 community respondents. Results of the TSI calculation of the Cengklik Reservoir for boat tours amounted to 2.40 (suitable) and fishing amounted to 3.00 (very suitable). The tourists perception of the Cengklik Reservoir as well as the communitys perception of tourism development were rated positively. These results indicate that the Cengklik Reservoir is suitable for tourism which is supported by the communitys perception of the tourist developmentKeywords: Cengklik Reservoir; Tourism Development; Tourism Potential; Tourism Suitability Index.

Lobster is one of the commodities that have high economic value in the world market. Thus, the export opportunities for lobster commodities are still promising. One area that can produce lobster in Indonesia is Bontang, East Kalimantan. The area which is the sea waters is very potential for lobster rearing cultivation. This study was conducted with the aim of analyzing good water quality in lobster rearing cultivation in Bontang, East Kalimantan. The study used 3 floating net cages by taking water samples 4 times and 5 lobsters each sampling. Water quality samples include physics (color, smell and taste, temperature, brightness), chemistry (pH, DO, nitrite, salinity), biology (coliform), heavy metals (hg, pb, cu). Lobster samples were measured by weight. The results showed that Fsignificant > 0.05 so that the water quality parameters had no effect on growth. The cause of the ineffectiveness of water quality parameters is due to the contamination of waters in Bontang, East Kalimantan.Keywords: Bamboo Lobster; Contamination; Floating Net Cage; Heavy Metal.

Abstract Yellowstripe scad (Selaroides leptolepis) is a small pelagic fish. Yellowstripe scad is one of the catches of mini purse seine fishing gear which has important economic value. Continuous fishing activities for yellowstripe scad can disrupt the sustainability of yellowstripe scad. The purposes of this study were to determine size structure, growth parameters, length-weight relationship, size of the first caught (Lc50%), mortality rate, and utilization rate of yellowstripe scad. This research was conducted in June, July, and August 2022 at Pekalongan Archipelago Fishing Port. The data was collected by using a simple random sampling method, taking a 10% random sample of fish from one of the baskets caught by the mini purse seine boat landed at Pekalongan Archipelago Fishing Port. The data collected included total length (mmTL) and weight (gr). Data analysis used FiSAT II program with analysis ELEFAN I. The results obtained a sample of 1081 individuals with a length range of 94-152 mmTL and a weight of 9-54 grams. The size of the first caught (Lc50%) was 113.88 mmTL. The length-weight relationship of the yellowstripe scad was W = 0.0000054L3,1614 and the growth pattern was positive allometric. Von Bertalanffy growth parameters of yellowstripe scad were Lt = 158.03[1 - e(-0.56(t+0.184))] with Lˆž was 158.03 mm; K was 0.56 and t0 was -0.184 years. The total mortality (Z) of yellowstripe scad was 1.86/year; natural mortality (M) was 0.77/year and fishing mortality (F) was 1.09/year. The exploitation (E) of yellowstripe scad was 0.58 which is included in the over-exploited category.Keywords: Exploitation; Growth; Mortality; Yellowstripe scad

Research on the effectiveness of ginger extract (Zingiber officinale Rosc.) against catfish (Clarias gariepinus) infected with Aeromonas hydrophila bacteria aims to analyze the antibacterial effectiveness of ginger extract against catfish injected with A. hydrophilla bacteria and to analyze the optimum dose of ginger extract as an immunostimulant in control of A. hydrophila infection. This research was carried out on January 26, 2021 to February 26, 2021 for 30 days and took place at the Microbiology Laboratory of the Faculty of Agriculture, the Laboratory of the Faculty of Mathematics and Natural Sciences and the Wet Laboratory of the Aquaculture Study Program, Faculty of Agriculture, University of Mataram. The method used in this study is an experimental method with a completely randomized design (CRD). The treatments were P1 (control), P2 (extract dose 30 ppm), P3 (extract dose 60 ppm) and P4 (extract dose 90 ppm). The ginger extract dose of 90 ppm (P4) was the optimum dose in the results of this study because it could give the best results on all the parameters measured. Keywords : Aeromonas hydrophila, , ginger extract. catfish

Water quality is one of the determining factors for the success of tiger shrimp in super intensive tiger shrimp culture that has very high productivity, this produces a lot of waste in the form of manure and leftover food which is a trigger for the decline in water quality. This study aims to determine the use of RAS using a different filter arrangement of water quality in the maintenance of tiger shrimp (Panaeus monodon). This research was conducted from August to September 2019 at the Hatchery and Aquaculture Technology Laboratory, Faculty of Agriculture, Malikussaleh University. The method used in this study is an experimental method with data collection techniques with a non-factorial Completely Randomized Design (RAL) consisting of 4 treatments and 3 replications that were treatment A without filter (control), treatment B: physics filter, chemical filter, biological filter, treatment C: chemical filter, biological filter, physics filter, and treatment D: biological filter, physics filter, chemical filter. The results showed that the use of different filter arrangements in RAS has an influence on water quality parameters except for temperature, increase in length, and weight and has a very significant effect on survival. The best water quality was found in treatment B, physical filter, chemical filter, band iological filter.Keywords: black tiger shrimp; Recirculating Aquaculture System; water quality

Excessive and periodic use of insecticides has a negative impact on aquatic areas and the biota in them. Pesticides that accumulate in the aquatic environment affect the life non target organisms such as fish. In addition, pesticides can cause damage to the gills, liver, intestines and spleen. This organ plays an important role in the immune system. Thus, an alternative is needed to overcome this problem, one of which is the addition of activated charcoal in the feed. The aims of study to determine the effect of the use of activated charcoal in feed on the histopathological description of the spleen of tilapia exposed to organophosphate pesticides. The study was conducted experimentally by applying 4 treatments and 2 replications as the treatments used included T1 (0% activated charcoal); T2 (1% activated charcoal); T3 (2% activated charcoal); T4 (3% activated charcoal). The test fish used were tilapia measuring 7 ± 0,4 cm long with a stocking density of 30 fish/container. Parameters observed were histopathological description of tilapia spleen at pre exposure, post exposure and after administration of activated charcoal. The results of observations of tissue damage were analyzed descriptively qualitatively and presented in the form of images. The results showed that the addition of 2% activated charcoal (T3) in the feed was able to reduce damage to the spleen due to exposure to organophosphate insecticides. Keywords: Activated charcoal; feed; insecticide; spleen

This study aimed to analyze the structure of the mangrove community including the identification of species, density, frequency, dominance, important value index, and mangrove basal area on Kapo-Kapo Island, Mandeh Region, Pesisir Selatan Regency. Mangrove community structure data collection was carried out by direct observation, starting with data collection and identification of species, number of individuals and diameter of mangrove tree. In collecting data on the structure of the mangrove community, water quality measurements were also carried out pH, salinity, temperature and looking at the substrate of the mangrove. Based on the results of the study, identified species of mangrove in Kapo-Kapo Island, Mandeh Region, Pesisir Selatan Regency, namely R. apiculata, S. casseolaris, and L. littorea. The average values of KR, FR, DR and INP on tree-level mangroves at R. apiculata were 97.00%, 65.00%, 93.02%, and 255.03%. S. casseolaris 1.82%, 28.33%, 6.14%, and 36.29%. L. littorea 1.18%, 6.67%, 0.84%, and 8.68%. The species R. apiculata had the highest Important Value Index from the tree level of the most dominating species on each transect.Keywords: Kapo-Kapo Island; mangrove; structure of the mangrove community

Environmental conditions that are quite important in the growth of mangroves are the type of sediment, organic matter, and water quality because the organic matter produced can be useful for mangrove fertility. This study aims to determine the type of sediment, the percentage of total organic matter, water quality, mangrove density, and determine the relationship between sediment types, total organic matter, and water quality on mangrove density on Tunda Island, Serang, Banten. This study used a survey method while collecting data using a purposive sampling method. Mangrove density was obtained through the line transect plot method. The sediment type test used the dry sieving method, the total organic matter (BOT) test used the loss on ignition (LOI) method, the statistical test used the multiple correlation method. All data was then analyzed in a quantitative descriptive manner. The results of the study are that the type of sediment in Tunda Island mangroves is dominated by silty sand and sand. The total organic matter contained in mangrove sediments ranges from 2.40% - 3.62% which is included in the moderate to high category. Salinity values ranged from 31 - 34.33 ppt included in the high category. The pH value ranges from 7.33 - 7.70 which is included in the good category for mangrove growth. Temperature values ranging from 27.37oC - 31.63oC are included in the good category for mangrove growth because they can still grow and develop normally. The mangrove density level is dominated by the dense category, which is 2,400 ind/Ha at station 1 and 1,700 ind/Ha at station 2, and the rare category is 1,000 ind/Ha at station 3 and 900 ind/Ha at station 4. There is a significant relationship between sediment type, total organic matter, water quality with mangrove density.Keywords: BOT; Mangroves; Sediment; Water Quality

Excessive and periodic use of insecticides has a negative impact on aquatic areas and the biota in them. Pesticides that accumulate in the aquatic environment affect the life non target organisms such as fish. In addition, pesticides can cause damage to the gills, liver, intestines and spleen. This organ plays an important role in the immune system. Thus, an alternative is needed to overcome this problem, one of which is the addition of activated charcoal in the feed. The aims of study to determine the effect of the use of activated charcoal in feed on the histopathological description of the spleen of tilapia exposed to organophosphate pesticides. The study was conducted experimentally by applying 4 treatments and 2 replications as the treatments used included T1 (0% activated charcoal); T2 (1% activated charcoal); T3 (2% activated charcoal); T4 (3% activated charcoal). The test fish used were tilapia measuring 7 ± 0,4 cm long with a stocking density of 30 fish/container. Parameters observed were histopathological description of tilapia spleen at pre exposure, post exposure and after administration of activated charcoal. The results of observations of tissue damage were analyzed descriptively qualitatively and presented in the form of images. The results showed that the addition of 2% activated charcoal (T3) in the feed was able to reduce damage to the spleen due to exposure to organophosphate insecticides. Keywords: Activated charcoal; feed; insecticide; spleen