Skip to main content

Sonnie A. Vedra

  • Biodiversity Journal, 15 (3): 649-658

    Mark Nell C. Corpuz, Hildie Maria E. Nacorda, Christine Marie E. Casal, Decibel V. Faustino-Eslava, Patricia Ann Jaranilla-Sanchez, Sonnie A. Vedra, Hermogenes M. Paguia & Ma. Victoria O. Espaldon
    Ichthyofaunal Diversity and Water Quality Parameters in Talisay and Bagac River Systems, Bataan, Luzon Island, Philippines
    https://doi.org/10.31396/Biodiv.Jour.2024.15.3.649.658

    ABSTRACT
    The fishery resources and hydrological data in the major river systems in Bataan (Philippines) are poorly studied. A preliminary study was conducted to assess the fish assemblages and water quality parameters along the three stream sections of Talisay and Bagac river systems (Luzon Island). The study collected 977 fish individuals from 50 species and 34 families; 28 fish species were observed in Talisay, whilst Bagac had 37 fish species. Forty-two fish species (84%) were categorized as native in the studied rivers. Family Gobiidae comprised the largest number of species in either river. Introduced or exotic fish species from the families Cichlidae and Cyprinidae comprised 16% of the total identified fish taxa. Among the cichlid family, the Sarotherodon melanotheron was the most abundant fish species (Talisay: n = 118; Bagac: n = 134). Shannon-Weiner’s diversity index in Bagac (H = 2.47) was higher than in Talisay (H = 1.91). The similarity rate of stream sections was low (27.28%) based on fish assemblage characteristics. In the ten water quality parameters, the levels of biological oxygen demand, fecal coliform, and total suspended solids exceeded the normal range for a Class C water body classification (agri-fisheries purposes), particularly in the midstream and downstream sections of the studied rivers. The present study supplied ecological datasets that can be adopted as bases to enhance the river conservation management measures in the region.

  • Biodiversity Journal, 14 (1): 0167-0171

    Sonnie A. Vedra, Ramon Francisco Q. Padilla & Rafael J. Vicente
    Macrobenthic Assemblages in the Riverine Systems in Kauswagan, Lanao del Norte, Philippines
    https://doi.org/10.31396/Biodiv.Jour.2023.14.1.167.171

    ABSTRACT
    Determining the composition of taxa and diversity of benthic macrobenthos could serve as reference in understanding the structure and function of riverine ecosystems. In this study, temporal and spatial variations in the distribution of macrobenthos were determined in dry and wet seasons in four sampling stations in the river and creek systems in Kauswagan, Lanao del Norte. A total of 272 specimens/m-2 benthic macrobenthos belonging to 6 taxa were identified, namely, Nematoda (42.28%), Oligochaeta (22.06%), Annelida (11.40%), Amphipoda (9.19%), Rotifera (8.46%), and Polychaeta (6.62%). Diversity index analyses indicated that Simpson index varied from 0.65 to 0.78, Shannon diversity values ranged from 1.21 to 1.62, while Dominance index ranged from 0.22 to 0.35, respectively, for all sampling stations during wet and dry seasons. Composition and diversity of taxa in all sampling stations for both wet and dry seasons were not significantly different (p>0.05). This means that macrobenthos population did not thoroughly changed through time and space. Thus, this study can be used in determining patterns and dynamics of biodiversity in ecosystems and try to manage their main aspects.