Abstract

Al Wathba Lake is located at Al Wathba Wetland Reserve which is located 40 km east of Abu Dhabi Island on the left side of the truck road to Al Ain. The water body extends for approximately 1.5 km in length and 0.5 km in width with a maximum depth of almost two meters (in the period of 2010). Al Wathba Reserve exists primarily because it is supplied with tertiary treated waste water from the Mafraq Waste Water Treatment Plant (WWT). The salinity of the water throughout the lake is variable due to the fresh water input and the underlying Sabkha substrate. The maximum salinity recorded in the lake is 230 ppt although typically the salinity is around 180 ppt. Over the period of February 2010 to December 2010, monitoring programme was carried out with the purpose of understanding the population dynamics, ecology and habitat requirements of the brine shrimp (Artemia sp.) at Al Wathba Lake which is the main food source for greater flamingo (Phoenicopterus roseus) in the reserve. Nine fixed sampling locations, distributed all over the entire lake’s area and two inlet samples were sampled monthly at day time to determine water temperature, salinity, pH, dissolved oxygen, nitrite, nitrate, ammonia, phosphate, total organic carbon (TOC), copper, cadmium and iron. The monthly average of total number of Artemia numbers counted in the sample was between 1.3 and 115 individuals/L but varied significantly between months. For the period considered, cysts were noted to be more abundant than the adults.

Key words: Water quality, brine shrimp, population, Al Wathba wetland reserve, physical parameters, chemical parameters.