Aquaculture, Aquarium,
Conservation & Legislation

Constructed wetlands (CWs) are increasingly recognized as sustainable systems for the treatment of aquaculture wastewater, where nutrient removal is governed by complex interactions among plants, microbial communities, and substrate processes. This review critically evaluates the potential role of selected textile and industrial crops - Chrysopogon zizanioides (vetiver), Phalaris arundinacea (reed canary grass), Cannabis sativa (hemp), and Hibiscus cannabinus (kenaf) - within CWs designed for aquaculture effluent remediation. The analysis highlights that nutrient removal is predominantly microbially mediated, while plant contributions are largely indirect, influencing rhizosphere conditions, oxygen transfer, and biomass harvesting dynamics. Among the evaluated species, vetiver demonstrates the strongest evidence for direct application in aquaculture wastewater, including tolerance to mesohaline conditions and effective nitrogen and phosphorus removal. Reed canary grass shows robust performance in CW systems, particularly when biomass management strategies are optimized, although aquaculture-specific data remain limited. Hemp is primarily supported as a biochar-derived substrate for phosphorus adsorption rather than as a planted macrophyte, while kenaf lacks direct evidence in CW contexts, representing a significant research gap. The review further emphasizes the importance of hydraulic loading rates, salinity tolerance, and plant–microbe interactions in determining system performance. Future research should prioritize long-term, field-scale studies and a mechanistic understanding of trait-mediated plant effects to optimize the integration of industrial crops into aquaculture wastewater treatment systems.

Vibrio alginolyticus is an important bacterial pathogen causing hemorrhagic disease and significant mortality in marine fish, including red drum, Sciaenops ocellatus (Linnaeus, 1766). This study evaluated the efficacy of an enteric-coated oral inactivated V. alginolyticus vaccine and optimized vaccination strategies to improve protection against vibriosis. A virulent strain (VA15) was selected for challenge experiments, with a median lethal dose (LD₅₀) of 2 × 10⁴ CFU fish-1. Juvenile red drum (14-16 g) were orally immunized with vaccine doses ranging from 10⁵ to 10⁷ CFU equivalent fish-1 to determine the optimal antigen concentration. Antibody titres increased significantly following vaccination and reached peak levels at 21 days post-immunization. As no significant difference was detected between the 10⁶ and 10⁷ CFU equivalent fish-1 groups, the 10⁶ CFU equivalent fish⁻¹ dose was selected for subsequent trials because it provided comparable immunogenicity while requiring less antigen. The protective efficacy of unencapsulated and enteric-coated vaccine formulations was subsequently evaluated using different booster schedules. Fish receiving the unencapsulated vaccine achieved a relative percent survival (RPS) of 44%, whereas enteric coating increased RPS to 54% following a single vaccination. Booster immunization further enhanced protection, with RPS values increasing to 61% and 78% when boosters were administered on days 14 and 21, respectively. These findings demonstrate that enteric coating improves oral vaccine delivery and that a booster vaccination administered 21 days after primary immunization provides the highest level of protection against V. alginolyticus infection. Although the study was conducted under laboratory conditions using a single bacterial strain, the results highlight the potential of enteric-coated oral vaccines as a practical disease management strategy for marine aquaculture.

The use of contaminated brine shrimp, Artemia franciscana (Kellog, 1906), as live feed leads to vibriosis outbreaks and threats to global aquaculture productivity. This study highlights a potential cost-effective and environmentally friendly approach to suppress Vibrio spp. load in Artemia live feed. Axenic A. franciscana nauplii were reared with Vibrio campbellii and Vibrio parahaemolyticus under 30-150 PSU of salinity. A salinity of 80 PSU can eliminate more than 90% of both strains, while maintaining over 90% survival of A. franciscana nauplii. Another experiment demonstrated that the Vibrio spp. load in non-axenic cyst-hatching tanks at 30 PSU was high but reduced with increasing salinities. The addition of 1 g L-1 Pandanus tectorius leaf extract in the high salinity rearing water significantly reduced cyst-derived bacterial load. Findings showed that 80-110 PSU of salinity is effective in suppressing almost all the Vibrio spp. without adverse effects on A. franciscana growth, removing the need for cyst disinfection or nauplii tank transfer.

Mangrove habitats are essential for maintaining biodiversity, protecting coastlines, and sequestering carbon, yet they are nevertheless subject to deterioration from human activity and natural disturbances. This study assessed the current ecological status and rehabilitation progress of the rehabilitated mangrove forest in Sitio Fuentes, Barangay Maria Cristina, Iligan City, Philippines. Monthly field assessments were conducted from March to December 2023 during spring low tides using ten 50-meter transect lines with systematically placed plots. Species identification and structural measurements were performed to evaluate species composition, density, and importance value. A total of 218 mangrove individuals were recorded, belonging to one family, one genus, and two species — Rhizophora apiculata and Rhizophora mucronata. Results revealed that R. apiculata was the dominant species, reflecting the typical composition of rehabilitated mangrove areas in the Philippines. The Shannon–Wiener diversity index (H’ = 0.68) indicated low species diversity, while the high density of seedlings and saplings (0.87 individuals m-²) suggested active regeneration and favorable recruitment conditions. However, the dominance of a single genus implies limited ecological resilience and restricted habitat complexity. The findings classify the mangrove area as having low biodiversity but with strong potential for recovery. Continuous monitoring and the inclusion of more diverse native species are recommended to enhance ecological balance, ensure long-term sustainability, and strengthen the mangrove’s protective and productive functions.

Tiger grouper (Epinephelus fuscoguttatus) is a highly valuable species and one of the most important fish traded in the live reef fish food trade (LRFFT). However, this species requires a desired growth pattern to command a high price in the market. Moreover, this species changes its growth pattern throughout the culture period, which may compromise its price value. Thus, the present study was conducted to determine the length-weight relationship and condition factor of this species for three (3) months of culture. There were 150 E. fuscoguttatus juveniles (mean total length: 24.24 ± 0.26 cm; mean weight: 252 ± 7.93 g) collected from the coral reef of Tandubas Island, Tawi-Tawi, Philippines. Fish were fed with 5% of their average body weight and individually measured for their length and weight using a measuring board and a digital weighing scale. Parameters, such as length-weight relationship and condition factor of E. fuscoguttatus were calculated before and after the cultured period. Results exhibited a lowering b value (i.e., from 3.00 to 2.96) and showed no significant difference between the wild caught E. fuscoguttatus at the time of capture and after their culture period (p > 0.05), suggesting an isometric growth pattern in both wild and cultured conditions. Apparently, an increasing condition factor (i.e., from 1.89 to 1.92) was observed in cultured fish. Moreover, a cultured grouper exhibited a significantly higher condition factor than the wild ones (p < 0.05), suggesting improved health condition when it is cultured as compared to the wild ones. Moreover, the results also suggested that growth patterns and condition factors can be manipulated through feeding management and dietary interventions. Overall, it implies that the growth pattern from the wild may be imitated in captivity, with appropriate cage management. Hence, it is feasible to produce cage-cultured grouper with body characteristics comparable to wild individuals.

The decreasing global population of horseshoe crabs highlights the need for conservation in areas where remaining populations persist. However, a limited understanding of community perceptions and behaviors can hinder the development of effective conservation strategies. Thus, this study measures knowledge, attitude, and practices (KAP) of the locals in Pangutaran Island, Sulu Province, Philippines, that can be integrated into future interventions and conservation strategies for horseshoe crabs in the area. A cross-sectional survey was conducted across 357 local coastal residents in three barangays of Pangutaran Island about their ecological knowledge of the horseshoe crabs in their locality, their attitude towards their population and conservation, and their current practices influencing the horseshoe crab population status. Findings showed that while ecological knowledge about the species remained limited (≤ 42%), majority expressed strong positive attitudes toward willingness to support conservation (55%). Active and bycatch capture of horseshoe crabs was reported by only a small proportion of respondents. However, the species continues to be utilized for traditional medicinal, cultural, and consumption purposes. KAP was significantly associated with sociodemographic factors, including occupation, educational attainment, and income (p < 0.001), and among its components. These findings highlight the importance of integrating ecological education with value-based community engagement to strengthen local participation in horseshoe crab conservation in Pangutaran Island.

The present study investigated the effect of two different hormones (17α-methyltestosterone and 17β-estradiol) on the sex reversal of African catfish (Clarias gariepinus) juveniles. For each hormone type, a total of three treatments and a control were used having different dosages of 100 mg kg-1 (T1), 200 mg kg-1 (T2), 300 mg kg-1 (T3), and 0 mg kg-1 (T0), respectively. The study also gathered the percentage of survival for each hormone. Each hormone was mixed with feed pellet using the alcohol evaporation method. The result of the sex reversal treatment for 17α-methyltestosterone showed that the male population increased as the dosage of hormone increases. Additionally, the sex reversal treatment using 17β-estradiol showed that female populations increased as the dosage of hormones increases. Treatments 1, 2, and 3 of 17α-methyltestosterone showed a significantly higher percentage of males compared to the control having 70.56%, 90.24%, and 100% males respectively. On the other hand, treatments 1, 2, and 3 of 17β-estradiol showed a significantly higher percentage of females compared to the control gathering 76.11%, 92.02%, and 98.89% females respectively. Meanwhile, the highest percentage of survival rate in 17α-methyltestosterone was observed in the control (55±7.0%) which showed a significant difference with treatment 3 (40.33±2.52%) (p < 0.05) who gained the lowest survival rate. Treatments 1 and 2 showed no significant difference among other treatments. On the other hand, treatment 3 of 17β-estradiol with 68.33±2.08% gained the highest survival with a significant difference between treatment 1 (56±3.61%) and the control (55±7.0%) but no significant difference with treatment 2 (58.67±3.79%). The present study proved that the use of 17α-methyltestosterone and 17β-estradiol can successfully masculinize and respectively feminize African catfish.

The fisheries sector is a strategic industry for both national and regional economic development in coastal regions that are rich in marine resources. Capture fishermen play a crucial role in supporting food security and regional economic growth in Serang Regency, which is predominantly coastal. Therefore, this research aimed to analyze the factors affecting the capacity and welfare of fishermen in Serang Regency. The analysis was conducted in eight subdistricts, namely, Pontang, Tanara, Tirtayasa, Kramatwatu, Bojonegara, Pulo Ampel, Anyer, and Cinangka, between November 2025 and January 2026. Purposive sampling was performed with the condition that the respondents were fishermen who had gone to sea for 1 year and who had used less than 5 GT of boats. The number of samples was 10 times the number of indicators (20), totaling 200 capture fishermen spread across the eight subdistricts in Serang Regency. Data analysis was performed using the structural equation modeling (SEM–LISREL) method. The results revealed that the factors affecting fishermen’s capacity were both internal and external, with direct and positive effects. Factors affecting fishermen’s welfare included external elements (X2), with significant direct and negative effects on welfare (Y2). Furthermore, fishermen’s capacity (Y1) significantly and positively affects welfare (Y2). The internal factors of fishermen (X1) also have a significant indirect and positive effect on the welfare of fishermen (Y2) through capacity (Y1).

The study was conducted in the recently established local marine conservation area in North Minahasa Regency of North Sulawesi, Indonesia, which was formally established in July 2023. The purpose of this study is to investigate seagrass diversity and coverage and derive management recommendations. Data collection was conducted using the line-quadrat transect method, comprising three transects, each 50 m in length, spaced 25 m apart. The study identified nine seagrass species: Halodule pinifolia, Halodule uninervis, Cymodocea rotundata, Cymodocea serrulata, Syringodium isoetifolium, Enhalus acoroides, Thalassia hemprichii, Halophila ovalis, and Halophila minor. The coverages of the seagrass at eleven observation stations were between 20.83 and 80.49%. The highest cover is at the LM10 station with a cover percentage of 80.49% or is included in the very dense category which is dominated by the species of seagrass T. hemprichii at 54.17%, the seagrass cover with the lowest percentage is at the LM07 station with a percentage of cover of 20.83% or included in the rare category which is dominated by the species of seagrass E. acoroides at 13.07%. Despite relatively dense conditions at several locations, the overall ecological status falls within the “unhealthy” category based on national standards. These findings indicate an urgent need for adaptive strategies to prevent further degradation of seagrass habitats within the marine conservation area.

The Napoleon wrasse (Cheilinus undulatus) is an ecologically and economically significant reef species native to Indo-Pacific coral reefs region, but it is increasingly threatened by overfishing and habitat degradation. Despite its endangered status under the IUCN and CITES Appendix II, there are limited data available on the growth patterns and physical condition of juvenile C. undulatus, especially in the wild. Thus, this study aimed to assess the length-weight relationship (LWR) and condition factor (K) of wild-caught juvenile C. undulatus. A total of 150 juvenile C. undulatus were bought from fishermen in Tandubas, Tawi-Tawi, Philippines. Samples were analyzed for its total length and weight using standard biometric methods. The LWR analysis of wild C. undulatus revealed a positive allometric growth pattern (b = 3.09), indicating that the fish grew more in weight than length, a typical trend in juvenile fishes. A coefficient of determination (R²) of 0.92) demonstrated a fitness of the data on the positive linear equations. It suggest the positive correlation of weight and total length in juvenile C. undulatus. Furthermore, the average K of 1.543 indicated that the juvenile C. undulatus were in good physical condition, suggesting favorable environmental conditions in their natural habitat. Overall, the study implicates the coral-reef conditions of Tandubas, Tawi-Tawi where C. undulatus thrive.

Effective water resource management is essential for sustainable regional development and maintaining quality of life in the environmentally sensitive Issyk-Kul Lake Basin. The main objective of the study is to examine existing water resource management issues, including transboundary distribution, as well as the impact of water usage on the water level in Lake Issyk-Kul. The study employed a secondary-data research design combining quantitative analysis of long-term hydrological and water-consumption records with qualitative analysis of water-management policies and institutional conditions based on long-term data (1980-2024), documentary analysis of water management reports, and seasonal comparisons of water consumption and precipitation patterns in the Issyk-Kul Lake Basin. The results show a substantial long-term reduction in irrigation and domestic water consumption, although agriculture remains the dominant water-consuming sector in the Issyk-Kul Lake Basin. It was also found that agriculture remains the largest consumer of water, especially between April and August, when increased rainfall is observed. However, the lack of synchronisation between natural water cycles and water consumption practices leads to negative effects on the water level of Issyk-Kul Lake. The analysis reveals that anthropogenic pressures, particularly agricultural expansion, outdated irrigation practices, and seasonal mismatches between water demand and availability, continue to exert significant stress on the lake’s hydrological balance and coastal ecosystems. These findings indicate that existing water management practices are insufficient to ensure long-term ecological stability and sustainable regional development, highlighting the need for adaptive and integrated water resource management approaches. The practical value of this research lies in the development of specific recommendations for optimising the use of water resources, including the strategy for using rainwater during periods of maximum precipitation.

The ocean is the most significant contributor to oxygen production on Earth due to the presence of chlorophyll-a contained in phytoplankton. One way to determine the concentration of chlorophyll-a is by using a smartphone camera through the HydroColor application. The data obtained through the HydroColor application does not directly provide chlorophyll-a data, instead, it provides red, green, and blue (RGB) wavelength data. This RGB wavelength data is then input into an equation to generate the chlorophyll-a concentration. This study aimed to evaluate the HydroColor application to estimate chlorophyll-a concentration. The research was conducted in Banten Bay, using field data collected with a smartphone and compared against laboratory test results and MODIS satellite imagery. Among several regression models tested, the logarithmic model showed the best correlation with laboratory results, with an R² value of 0.83 and a correlation coefficient of 0.876. The HydroColor application can be practical in coastal water bodies with a smartphone featuring a high-resolution camera. This study demonstrates that HydroColor has the potential to serve as an alternative method for estimating chlorophyll-a concentration in Banten Bay.

This study examined the effects of adding the probiotic Saccharomyces cerevisiae to feed on feed efficiency, growth performance, digestive enzyme activity, and body biochemical composition of striped catfish (Pangasianodon hypophthalmus). The test fish were striped catfish with an initial average weight of 20.36±0.22 g fish-1. The test feed was a formulated pellet diet with S. cerevisiae probiotics added at different doses: T1, T2, T3, T4, and T5 (0, 1, 2, 3, and 4 g kg-1 feed, respectively). The test feed was administered using the ad satiation method thrice daily for 56 days. The results showed that adding S. cerevisiae probiotics to the feed significantly increased the feed efficiency, growth performance, digestive enzyme activity, and biochemical composition of striped catfish. Both feed efficiency and growth performance variables in striped catfish increased with increasing doses of S. cerevisiae probiotics. The same trend was observed for the digestive enzyme activity and biochemical composition of striped catfish. An additional 4 g kg-1 feed of probiotic S. cerevisiae was identified as the best dose for improving the productivity of striped catfish (P. hypophthalmus).