Refining benthic macroinvertebrate kick sampling protocol for wadeable rivers and streams in Ethiopia

Area of Science:

• Environmental Science
• Ecology
• Aquatic Biology

Background:

• Freshwater ecosystems like rivers and streams are vital but face significant human impact.
• Bioassessment methods are underdeveloped in many developing nations, including Ethiopia.

Purpose of the Study:

• To compare the efficacy of 2- and 3-minute macroinvertebrate kick samples for stream bioassessment in Ethiopia.
• To evaluate different sampling approaches, including riffle habitat (RH) and multihabitat (MH) methods.

Main Methods:

• Statistical analysis of benthic macroinvertebrate metrics and diversity indices.
• Kruskal-Wallis tests to compare sampling methods.
• Multivariate analyses (ANOSIM, RELATE, MDS, CS-SMC, IMD) to assess community similarity and variation.

Main Results:

• No significant differences were found among sampling methods in minimally impacted Ethiopian streams, except for total and Ephemeroptera abundances.
• Multivariate analyses indicated high similarity in macroinvertebrate communities across all tested methods.
• The index of multivariate dispersion (IMD) revealed variations in community relative abundances among methods.

Conclusions:

• The 2-minute RH kick sampling method is a viable and efficient option for bioassessing wadeable rivers and streams in Ethiopia.
• This shorter method is suitable when rare taxa or detailed taxonomic identification (genus/species) are not the primary focus.