Mr Habte Tefera is a fisherman living in the Amhara State of South Gonder Zone, Fogera Wereda, Nabega Kebele, on the shore of Lake Tana. He has been fishing for over 20 years to cover the livelihood expenses of his nine family members.
'This invasive water hyacinth 'Enboch' is very dangerous. Even though it came here in recent years, it is highly affecting the communities' lives right now', Habte says. "We are getting nothing today. The resource of Lake Tana has been destructed by the water hyacinth."
Today, in fact, Tana is critically infested with water hyacinth, Eichhornia crassipes, locally known as 'Enboch'. It is putting the aquatic biodiversity of the Lake at extreme risk. The vast swathes of the water around the lakeside in South Gondar Zone of Fogera Wereda_are becoming a sea of green, fish pens and navigation channels alike clogged by an impenetrable mass of water hyacinth. It is shocking while any one sees the amount of water weed that have been covered.
"The lakes water is very cold as it is covered by the water weed. Fish needs sunlight for breeding. The hyacinth mats are negatively affecting their productivity," Habte says.
Studies also show that water hyacinth mats have invaded fishing grounds and blocking waterways in Lake Tana. Since the invasion of the water weed, the production of fish has decreased and the price has been inflated. It has also affected the test of the foods made up of fish, as to Habte.
Birhanu Wubnhe lives in Gondar city. He has been selling fish for the last 12 years. He has promoted modern fishing system within five Woredas which are now affected by the hyacinth. He is vibrant environmentalist who has been insisting that the state government and research institutions should give due emphasis to cultural or indigenous knowledge of the communities' in order to get rid of the weed. "Water hyacinth has destroyed our ecology and thus fish resources. The wetlands have been dry lands," Birhanu says. "The trend in controlling 'Enboch' was encouraging from 2011-2013 and only four Kebeles were affected during that time. Since then additional 14 Kebeles were affected with the invasive weed."
Deacon Alemu Belachew is an administrator of Nabega Kebele, Fogera Wereda in South Gondar. He calls up on the state and federal governments to provide additional support to get rid of the invasive weed. "It is difficult to remove 'Enboch' just by human power. Even though we have been striving to get rid of it by mobilizing the communities starting from 2017, it is still spreading at alarming rate and threatening the survival of the Kebele."
The situation has also implications to regional hydro-politics as the Lake is the main source of the Blue Nile. The weed can destroy the fishery industry, create obstacles to navigation, clog canals of hydroelectric power plants and will generally create serious environmental imbalance, according to researchers, Goraw Goshu and Shimelis Aynalem.
"There are three irrigation dam projects which have been built by federal government around Lake Tana basins, named as 'Rib', 'Megech', and 'Megech Serba'. These projects are being implemented on the infested ecology. If the current pace of the weed invasion continues, we will lose the billion dollar projects," warns Birahnu Wubnhe, local environmentalist.
Some also fear that the situation would affect the Grand Ethiopian Renaissance Dam. As to some environmentalists, the water hyacinth is primarily the responsibility of the Ethiopian Federal government, and second downstream countries, in particular Sudan and Egypt should be consulted if they have willingness to contribute something to guarantee the water flow of the Nile. "This plant is water thirsty, hence first it minimizing and later it depleted the flow of the Nile water. If the problem persists, dams both in Ethiopia and the two downstream countries would be affected," environmentalists warn.
On other hand, the weed is also threatening the hub of Ethiopian ancient history and glory in the Lake with a unique religious, historical and aesthetic value, 37 highlands and so many monasteries and churches dating back to the 13th century. Religiously, the Lake has special place as it is home to many unique churches and monasteries of the Ethiopian Orthodox Tewahedo Church. Epistemologically, the lake is believed to be a source of knowledge and ancient Ethiopian wisdom and glory. These churches and monasteries contain valuable treasures of the Ethiopian Christian faith. Historians label Lake Tana as a mystical place where time and history run deep.
For these and other many reasons, the United Nations Educational, Scientific and Cultural Organization (UNESCO) designated the Lake Tana as a World Heritage site for its unique ecological biosphere reserve in June 2015.
Dr. Ayalew Wondie is an Associate Professor of Aquatic and Wetland Science at Bahir-Dar University. He is a renowned researcher of water hyacinth. He found the water hyacinth in the Lake seven years ago.
"The Bair Dar University research team along with the Amhara State Bureau of Agriculture identified the occurrence of water hyacinth in 2011 after taking sample and making experiment. By then, we understood the water weed has great impact on Lake Tana wetlands and ecology. We were shocked at that time," says Dr. Ayalew. Dr Ayalew says that the actual cause which brought water hyacinth has not been known. However, he and his research colleagues predicted that it was caused by migratory birds, used and contaminated fishing materials which came from neighboring countries, and using water hyacinth as ornamental plant.
There are so many aggravating factors for the expansion of water hyacinth in Lake Tana. Pollutant chemicals which come from agricultural land and urban areas are the first ones. 'There are an intensive agricultural activities at 'Dembiya' and 'Fogera' Woredas which rush out and drain the used pesticides and fertilizers to the buffer zone whereby water hyacinth gets its nutrient for growing,' Dr. Ayalew says.
Even though a water hyacinth infestation is hard to get rid of, Dr Ayalew Wondie and other Aquatic wetland scientists noticed that there are three ways to do this globally: removal (manual and mechanical), chemical spraying (using herbicides) and biological control methods.
Manual method is advisable to apply when the scale of infestation is at minimal level, but it doesn't work in Lake Tana where the coverage is at high level, according to Dr. Ayalew. "Different countries use chemical method with respect to their environment. When we come to Lake Tana; people drink the water, use it for sanitation, and livestock. So we don't also advise the government to use this method."
"Biological method is a common practice everywhere. We need to have natural enemies to employ. Unfortunately, the water hyacinth did not come here with its natural enemy. Natural enemy do not have negative impact on ecology. So, it needs a number of field trials and experiments in Lake Tana. As university, we are working on it although it is not feasible. Even though this method is known to be effective, it is not an immediate solution for our problems," Dr. Ayalew says.
Even though Dr. Ayalew believes that biological method which needs natural enemies to employ is an effective method, he recommend manual method in order to avert the extreme expansion of water weed and its negative impacts on many economic, social, ecological resources. 'We should give attention to manual method by recognizing and giving support for cultural or indigenous knowledge of the local communities. I am an advocate of this idea,' says Dr. Ayalew. He also focused on synthesizing the fragmented local communities' cultural or indigenous knowledge.
"Even though various research institutes and researchers have been conducting research works to control the water weed, we have not disclosed the results due to the fact that they are still in testing phases," says Mezgebu Dagnew, Director of 'Enboch' Weed Removal Directorate at Amhara State Bureau of Environment, Forest and Animal Resource.