is also a freshwater lake, and it has five islands of which one is said to have housed the Ark of the Covenant during 16century in order to protect it from an Islamic warrior named Gragn as nickname. The lake is fed by the Meki and Katar Rivers, but does not always have an outflow; sometimes it overflows into Lake Abiata. The lake has plenty of hippo in it, and has a healthy population of birds. With large numbers of Tilapia nilotica, a fish that can weigh up to 1.5 kg, the fishing industry does well here and the fish are served fresh in many of the restaurants in the nearby town. The fish also attract a large number of water-associated birds, which can be seen in the reed-lined fringes of the lake. Lake Abiata is to the south of Lake Ziway, and to the north there are a number of hot springs which are important to the locals, and are also a popular tourist attraction. The lake is saline, and has recently undergone a decline in water level. This has resulted in the loss of fish-eating birds as the fish have died, but an increase in algae-eating birds such as greater and lesser flamingos.