Description of the Study Area
Zegie Peninsula (11° 43' N, 37° 20' E) is located at 600 km
northwest of Addis Ababa in the country's northwest highlands, at an
altitude of approximately 1800 meters. It is partly surrounded by Lake
Tana, which is the largest lake in Ethiopia and the source of the Blue
Nile. Zegie Peninsula is about three hours motorboat drive or 37 km on
land from Bahir Dar, the capital city of Amahra Regional State (Fig. 1).
The residents are Amahra people and speak the country's official
language Amharic. Tankwas (papyrus boats) of ancient design,
manufactured on the shores of Lake Tana, are the alternative forms of
transport for the local people between Zegie and Bahir Dar. There are
seven monasteries on the peninsula from the 16th and 17th century. Ura
Kidane Mhret, one of the monasteries, houses myriads of treasures,
beautiful mural paintings, icons, scrolls and thousand-year-old
manuscriptsas well as crowns and dresses from Ethiopian Emperors.
During the study time, there were no modern health facilities in the
area. The main occupation of the people is fishing, and coffee
plantation. Until recently, there was no farming practice because the
monasteries in the peninsula had forbidden the use of any type of draft
animal for farming. Nevertheless, currently, the people have started
farming and clearing the forest for agricultural purposes and this may
affect the natural habitats of some of the medicinal plants.
Survey on the Use of Medicinal Plants
The ethnobotanical surveys were carried out from October 2005 to June 2006 using semistructured questionnaire [17]
and interview was conducted in Amharic. Prior to the administration of
the questionnaire, conversations with the informants were held with the
assistance of local Farmers' Association representative to elaborate
the objective of the study and to build on trust with the common goal
to document and preserve the knowledge on medicinal plants. Two hundred
informants were interviewed out of about 2855 inhabitants (1,338
females and 1517 males) of the Zegie peninsula (unpublished data, Bahir
Dar Zuria Woreda Administration), these included 130 males and 70
females. Of which, six were male local healers (the only ones found on
the peninsula). The female informants' age ranges from 30 to 85 years
and the mean age is 51 years, and the male informants' age ranges from
30 to 93 years and the mean age is 64 years. The informants, except the
healers, were selected randomly and no appointment was made prior to
the visits. They were asked to give their knowledge about the plants
they use against a disease, plant parts harvested, method of
preparation of the remedy, details of administration and the dosage.
Specimens of the reported medicinal plants were collected during
regular systematic walk in the fields and identified by specialists at
the Aklilu Lemma Institute of Pathobiology and the National Herbarium
of Addis Ababa University following the Flora of Ethiopia and Eritrea [18-21]. Voucher specimens were deposited at the Herbarium of Aklilu Lemma Institute of Pathobiology, Addis Ababa University.
Data Analysis
The reported aliments were grouped into 10 categories based on the
information gathered from the interviewees. The categories were: evil
eye and 'satan beshita' (devil sickness), external injuries and
parasites infections, gastrointestinal disorder and parasites
infections, 'mich' (febrile disease characterized by fever, headache,
sweating, Herpes labialis, and muscle spasm) and febrile
diseases, rabies and internal disease, respiratory and throat
infections, sensorial disease, snake bite, swelling (non-infectious or
infectious swelling) and cancer, and venereal disease and impotence.
Informant consensus factor (ICF) was calculated for each category of
aliments to identify the agreements of the informants on the reported
cures for the group of aliments. ICF was calculated as follows: number
of use citations in each category (nur) minus the number of species used (nt), divided by the number of use citations in each category minus one [22].

The fidelity level (FL), the percentage of informants claiming the
use of a certain plant for the same major purpose, was calculated for
the most frequently reported diseases or ailments as:

Where Np is the number of informants that claim a use of a plant
species to treat a particular disease, and N is the number of
informants that use the plants as a medicine to treat any given disease
[23]. These two methods are helpful in the selection of plants for further studies.