Ecohydrology of Seasonally Flooded Forests in the Niger Delta and Their Significance for Wildlife Conservation

Seasonally flooded freshwater forests in the Niger Delta region of Nigeria's South South geopolitical zone represent a globally rare and ecologically specialized ecosystem type that supports extraordinary biodiversity including endemic fish species, freshwater turtles, and specialized avian communities. Yet the ecohydrological dynamics governing these forests, and their implications for wildlife habitat quality and conservation management, have received minimal scientific investigation. This dissertation investigates the ecohydrology of seasonally flooded forests in three distinct Niger Delta forest areas across Bayelsa, Delta, and Rivers States, examining the relationships between hydrological regime, forest structure, and wildlife community composition. Hydrological monitoring stations were installed at 18 sites to record inundation depth, duration, frequency, and recession rate over two annual flood cycles. Vegetation structural assessments and wildlife surveys, including fish diversity sampling during inundation periods and mammal and bird surveys during drawdown, were conducted at all sites. Path analysis examines the causal pathways through which hydrological variability drives vegetation structure, which in turn determines wildlife community composition. Results demonstrate that flood duration is the primary driver of tree species composition and canopy structure, which in turn explains the largest proportion of variation in fish and waterbird diversity. Oil industry infrastructure is found to have significantly altered hydrological regimes at two sites, with associated reductions in wildlife diversity. Original contributions include a Niger Delta flooded forest ecohydrological classification system and a hydrological management guidelines framework for conservation-compatible water management. Keywords: ecohydrology, seasonally flooded forests, Niger Delta, South South Nigeria, wildlife habitat