The Effects of Wetland Droughts on a Reserve in the African Continent

Abstract

Climate change and its attendant fallouts such as drought, flood etc affect every aspects of environment including wetland ecosystem. This paper seeks to examine the effects of droughts on Dagona Waterfowl Sanctuary?an important wintering area for migratory birds in Bade local government, Yobe state, Nigeria. The study used annual rainfall data collected from the archives of the Nigerian Meteorological Agency (NIMET) with respect to Nguru weather station in the area for a period of 1956-2015. Standardized Precipitation Index (SPI) in conjunction with Percentage Deviation Below Mean (PDBM) models were applied for comprehensive drought detection on a time scale of twelve (12) months. SPI anomaly graphs were plotted to depict drought of varying magnitude. The researcher went round the sanctuary and made observations with the help of binocular and telescope. Findings explicitly revealed that the study area was replete with droughts of varying intensities ranging from mild, moderate, severe and extreme ones. And high magnitude droughts led to hydrological changes causing drying up of wetland water, decreased production of seeds that provide forage opportunities, intrusion of invasive species such as typha grasses forming dense biomass that hinder birds to prey on fishes or swim freely. The result of the analysis would add to the mainstream theoretical body of knowledge about droughts effects on wetlands. The research concludes that droughts of high magnitude occurred variably and affected both native and migratory birds in the study area and hence recommend the integration of disasters like drought in the management strategies of the wetlands.