The study aimed to quantify and qualify the microplastics in the gastrointestinal tract contents of the six (6) dominant demersal fish species, determining the percentage frequency of occurrence and the condition factor. Out of 180 fish individuals examined, 21 samples (11.67 % of the total samples) have microplastics in their gastrointestinal tracts. The microplastics observed were fibers which occur the most (count = 22; %FO = 78.57 %), followed by microbeads (count = 5; %FO = 17.86 %) and rubber (count = 1; %FO = 3.57 %). The Spangled Emperor, L. nebulosus, was the highest consumption of 13 (46.43 %) fiber and 1 (3.57 %) microbeads in the stomach. No microplastic in the stomach of the Brown-stripe Snapper, L. vitta. The fish samples without microplastics ingestion differ significantly from fish with microplastics in the stomach. The fish samples without microplastics ingestion displayed a good and well-proportioned fish, while fish with microplastics is as a poor fish, long and thin.

A research based fishery management would lead to more sustainable fishery resources. This study aimed to provide biological and reproductive data of Channa striata from Lake Mainit Philippines. Length-weight relationship, condition factor, gonadosomatic and hepatosomatic indices were determined in this study. Results revealed that snakeheads showed a significant difference in terms of body weight and gonad weight. Females weighed heavier than males. Female gonads were heavier than males as it had high percentage of mature stage (53.13%) in terms of gonadal development compared to male which were in maturing stage (47.83%). Female snakeheads preponderated the males in terms of sex ratio (1:0.72). The length – weight relationship revealed an allometric growth pattern. Female snakehead demonstrated positive allometric pattern (b=3.3143) while male snakehead showed negative allometric growth pattern (b=1.7267). The values for the condition factor in both sexes of snakehead were less than 3, indicative of a poor condition which may be attributed to the threatened environmental condition of the lake. The GSI values in both sexes are high and greater than 1, implying of their fecundity as revealed and consistent to the observed stages of gonadal development. The HSI values for female and male snakehead were minimal, suggestive of low hepatic activity. An inverse relationship between GSI and HIS has been shown in this study. The values on the body parameters and reproductive biology of C. striata from Lake Mainit, Philippines are vital baseline information for rational fishery management in the lake. A study on temporal and spatial distribution of C. striata caught from this lake and its tributaries may be conducted to elaborate further its reproductive biology particularly on its spawning season to provide significant knowledge in the promotion of C. striata utilization and capture production as well as in the restoration of Lake Mainit fishery resources to sustainability.

This study evaluated the presence of microplastic ingestion by bigeye scad, Selar crumenophthalmus from the Municipal Waters of Malimono, Surigao del Norte, Philippines. The microplastics were found in seven (7) fish individuals (11.67%) from a total of 60 fish samples examined, with an average of 0.12 ± 0.04 (mean ± SD) items per fish. Fibers (42.86%) made up the majority of the ingested plastic, followed by beads and fragments (28.57%). Only one piece of plastic was found in each of the stomachs of the seven fish samples that had consumed microplastic. The amount of microplastic that fish consumed in this study is relatively low compared to other findings from various locations. The statistical analysis proved that there is no significant difference (p>0.05) in the condition of all samples with or without microplastic ingestion in the stomach. The mean relative condition factor (Kn) both with and without microplastic ingestions is (K>1), which indicates that fish have good condition.

This study evaluated the presence of microplastic ingestion by bigeye scad, Selar crumenophthalmus from the Municipal Waters of Malimono, Surigao del Norte, Philippines. The microplastics were found in seven (7) fish individuals (11.67%) from a total of 60 fish samples examined, with an average of 0.12 ± 0.04 (mean ± SD) items per fish. Fibers (42.86%) made up the majority of the ingested plastic, followed by beads and fragments (28.57%). Only one piece of plastic was found in each of the stomachs of the seven fish samples that had consumed microplastic. The amount of microplastic that fish consumed in this study is relatively low compared to other findings from various locations. The statistical analysis proved that there is no significant difference (p>0.05) in the condition of all samples with or without microplastic ingestion in the stomach. The mean relative condition factor (Kn) both with and without microplastic ingestions is (K>1), which indicates that fish have good condition.