Biodiversity and water quality of Mukura forest and biosphere reserve, Western Rwanda

Mukura Forest is a biodiversity hotspot within the Albertine Rift essential for biodiversity conservation, climate regulation, and provision of water resources. Despite its importance, a comprehensive biodiversity and water quality assessment was lacking. This study surveyed plants, birds, mammals, amphibians, reptiles, terrestrial arthropods, butterflies, water macroinvertebrates, diatoms and water quality. Water macroinvertebrates were collected by using the kick-nets and hand searching, while diatoms were sampled by substrate scraping. Further, water physicochemical properties were measured in situ using HQ40d Multimeter. Terrestrial arthropods were sampled through hand collection, sweep nets and pitfall traps, while butterflies were sampled using the sweep-net and baited traps. Birds were recorded via point counts and opportunistic observations; reptiles and amphibians were sampled through active searching and visual encounter surveys; mammals were trapped using Sherman live traps while vegetation was sampled using circular plots for woody species and nested quadrats for herbaceous plants. Collected specimens were identified using identification keys to the family and to species levels where possible. Results have indicated a total of 1 523 individuals of water macroinvertebrates and 25 diatom species. Results have also indicated 4 044 individuals of arthropods including 24 butterfly species. Avian surveys documented 124 species, with 12 Albertine Rift endemics and the critically endangered Hooded Vulture. Amphibians and reptiles yielded 12 and five species, respectively. Identified small mammals included 12 species, with three new records for Mukura. The floristic assessment identified 255 species, with two newly recorded. These findings underscore the significance of Mukura for biodiversity conservation and water quality. There is a need to identify collected specimens to specie level, make continuous study in Mukura and other tropical forests of Rwanda.