Ecological assessment of Cheffa Wetland in the Borkena Valley, northeast Ethiopia: Macroinvertebrate and bird communities

Ecological Indicators (Impact Factor: 3.44). 04/2012; 15(1):63-71. DOI: 10.1016/j.ecolind.2011.09.011

ABSTRACT A comparative study of macroinvertebrates and bird communities was undertaken to assess the ecological
integrity and human impact in Cheffa Wetland, northeastern Ethiopia. The study was undertaken from
February to May 2010. Physicochemical parameters of the water, birds, macroinvertebrates and human
impact classes were assessed at 10 sites in the wetland exposed to different anthropogenic activities. We
have compared Shannon index of diversity of macroinvertebrates and birds along with different habitat
classes. Multivariate statistics were used to extract the main driving forces for changes in macroinvertebrate
and bird community patterns out of a complex data set. Subsequently, we compared the diversity
indices of the macroinvertebrate and bird communities for the detection of human impacts. A total of
2789 macroinvertebrates belonging to 34 families in 10 orders were collected and 3128 birds belonging
to 57 species recorded. Macroinvertebrates belonged to five different orders: Hemiptera (seven families),
Coleoptera (five families), Odonata (five families), Gastropoda (seven families) and Diptera (five families),
exceeding 77% of the overall sample. Abundance and diversity of the bird and macroinvertebrate communities
were related mainly to concentrations of DO, nitrate and chloride, habitat conditions, and human
disturbances. Of the 57 species of birds recorded, the cattle egret (Bubulcus ibis), white-faced whistling
ducks (Dendrocygna viduata), Egyptian goose (Alopochen aegyptiacus) and spur-winged lapwing (Vanellus
superciliosus) were the most abundant. The physicochemical variables showed great variation among
sites. The results revealed that human interference in wetland may result in serious ecological imbalances
in the natural life cycle and impact on human welfare. Long-term studies are required to predict changes
in wetland ecology and population dynamics, with the objective of developing appropriate measures by
federal, regional and local stakeholders to ensure wetland restoration and sustainability.

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