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Exploring the length-weight relationship of fish and characterising growth parameters is essential in fisheries as they offer fundamental biology and population dynamics data to establish good management strategies for fisheries resources. This study examines the growth and mortality patterns of Oreochromis mossambicus. Data was collected between September and December 2022 using quantitative descriptive survey sampling. The study involved 20 repeats and deliberate random sampling of 30-50 fish per sample, emphasising total length, weight, and sex parameters. Based on 726 samples of O. mossambicus (352 fish identified as male and 374 fish identified as female). The growth model study revealed the typical negative allometric growth for both sexes (male and female). Male individuals attained a length of 33.449 cm after 37 days has a growth trend ± 0.3265 year-1, and females reached 21.150 cm in 34 days with a growth rate around 0.3135 year-1, as per the von Bertalanffy growth model. There were complex mortality patterns, with males contributing to most total deaths. This study emphasizes the complex biology of tilapia and its untapped potential in the aquaculture pond system ecology in Tarakan. [ABSTRACT FROM AUTHOR]

This survey is part of the installation of Tripod Jackets in Makassar Bay, targeting the North Side, North Nubi and Jumelai, PT Pertamina Hulu Mahakam in East Kalimantan waters. This study aims to provide marine mammal observation to the JSN project. Expert help is essential because it complies with the International Maritime Organization MEPC.1/circ.833 rules. From 13th April to 2nd June 2021, observations were made using visual and passive acoustic methods (SQ26: H1 recorder). The visual observation focus was from 500 meters to 1000 meters. The team found that the dolphins that appeared were bottlenose, long-beaked, and dolphins were not identified. The highest prevalence was during the pilling of 12 dolphins at JML 1 site (after the GTS installation and adjustment). Long-beaked and unidentified dolphins were found in WPN 4 location. The dolphins seen were Tursiops species, while the turtles seen were green turtles. When watching dolphins, sightings occurred mainly at night. In the next task, the collection process, we want to discuss the process that produces a high sound on the water’s surface. We recommend using “early warning”. The warning will be done after the routine inventory, and we hope the staff can do it three times.

Reef composition and diversity of coral reef fishes play an essential role in the ecosystem. The reef fish diversity is a crucial indicator of the health level of coral reef ecosystems. The benefit of fish diversity in coral reef ecosystems is to describe ecological services. This research intended to determine reef fish diversity among stations at different depths, consisting of shallow water and reef slope. Research sampling was done in July 2018 and July 2019 in Tunda Island waters at eight stations billowing the coral distribution pattern. Collected data of reef fishes were by using Underwater Visual Census (UVC) on Belt Transects Method at 250 m² transect area (50 meters of length and 2.5 m on either side). The result showed 69 reef fishes in shallow water and 67 species on the reef slope. The total of fish species ware from 13 families consisting of Acanthuridae, Apogonidae, Blenniidae, Chaetodontidae, Ephippidae, Haemulidae, Labridae, Lutjanidae, Nemipteridae, Pomacentridae, Pseudochromidae, Scaridae and Serranidae. The community services structure of coral reef fishes is included in the moderate community stability category with an H’ value ranging from 1.19- 1.60 in shallow water and 1.23-1.44 at reef slope, respectively. Diversity in coral reef fish communities might be associated with species' spatial distribution over the reef habitat's physical structure, but these patterns could be highly scaledependent. In general, it could be said that the higher the coral reef diversity, the higher the reef fish diversity. [ABSTRACT FROM AUTHOR]

This study examines the agent behavior during a complex tsunami process to reach designated shelters based on the agent-based modeling approach. A GIS-based tsunami inundation modeling is employed considering the land slope and surface roughness coefficient to estimate the tsunami height loss. This model becomes the basis for determining the service area within the study site. Five shelter candidates are assessed using agent-based modeling simulated in the NetLogo, implementing the 50 minutes ETA and 9 meters tsunami run-up propagation for four population age classifications. Overall, the Panimbang coastal area is categorized as a high vulnerability to tsunamis (14.68% of the total area), where the run-up propagation is extended due to the tsunami invading rivers, thereby increasing the risk toward local society. Of particular concern, two proposed shelters (SA1 and SA5) exceed the capacity by 12.43% and 59.44% of their maximum capacity, respectively. Of 9,640 agents (people) simulated, 77.7% are evacuated, and 22.3% fail to reach the shelters, with a majority of the adult category. A sufficiently high casualty number is due to a "bottleneck" in the overlapping service areas. However, reconsidering the overcapacity TES with some additional shelters in the surrounding area is recommended. [ABSTRACT FROM AUTHOR]