Abstract:
Drought is defined as the protracted absence, deficient or poor distribution of precipitation
and it is a natural phenomenon that occurs for prolonged period of abnormally low precipitation. The
underlying causes of most droughts can be related to changing weather patterns manifested through
the excessive buildup of heat on the earth’s surface, meteorological changes which result in a
reduction of rainfall, and reduced cloud cover, all of which results in greater evaporation rates.
Nowadays drought is the main problem in the world and also recently in Ethiopia. Ethiopia has
experienced droughts for hundreds of years, with major events (i.e., ones involving famine or
documented suffering) including 1888-92, 1899-1900, 1920-22, 1933-34, 1973-74, 1983-84, 1987-88,
1990-91, and 1993-94. Currently, Ethiopia has faced the ugliest drought in 2015/2016 which affects
the environment and humans. Mostly the occurrence of drought in Ethiopia is related to El Niño
Southern Oscillation (ENSO) events. Reservoirs are essential components of most irrigation systems
worldwide and, together with those built for flood control and power generation, retain large volumes
of water. In addition to their roles in power generation and provision of water for agriculture, industry
and homes, most of these reservoirs also play an important role in fish production and contribute
significantly to the livelihoods of the communities along their shores. It is known that Ethiopia has
huge reservoir fish production potential which is not revealed and unexploited. One of these
reservoirs, Tendaho Reservoir, is found in Afar region located between Dubti and Mile. This large
reservoir has faced a great problem being highly vulnerable for drought in which it has dried, at least,
once in the last two years. Recently, in February 2016, it has totally dried due to El Niño and all living
organisms in the reservoir were damaged. It has distracted community structure, habitat loss, decline
and huge fish population has died out. In this area, there is a knowledge gap on cause and effect of El
Niño in reservoir ecology; therefore it needs depth research which could be conducted on drought
impact in reservoir in order to develop prevention techniques during drought season.
Therefore, the purpose of this review paper was to identify effects of El Niño on reservoir fish
production by synthesizing current knowledge on effects of drought on reservoirs that would ultimately
be used to recommend and identify research direction.
