The Niger Delta faces severe ecological stress, with anthropogenic stressors and pollution contributing to species depauperation and declining ecosystem integrity. Plankton, as keystone and sensitive bioindicators, provide critical insights into trophic interactions and ecosystem health. This study employed a mixed-method study design involving field sampling, ecological surveys, and ethnobiological questionnaires to examine plankton distribution in the Otuoke Creek channel. Water samples from three randomly selected locations (each with two sampling points) were analyzed alongside physicochemical parameters (temperature, DO, BOD, TDS, turbidity, conductivity, pH) and meteorological factors (humidity, wind speed, temperature). Findings revealed significant variation in plankton abundance, diversity, and trophic structure, driven by climatic conditions, anthropogenic pollution, natural dynamics and ethnobiological practices. Species distribution followed an atypical trophic sequence: phytoplankton (Autotrophs, 76.6%, n=372) > phyto-zooplanktivores (Omnivores, 21%, n=103) > phytoplanktivores (Herbivores, 1.4%, n=8) > zooplanktivores (Carnivores, 1%, n=5). These patterns suggest interactive stressor effects (synergistic, antagonistic, or additive) that influence ecosystem resilience. Ethnobiological data further underscored awareness and role of human activities in nutrient enrichment and habitat alteration. Overall, the study demonstrates that plankton communities serve as effective indicators of environmental change and should inform adaptive management, conservation, and community-driven monitoring strategies in the Niger Delta.