Artisanal mining impacts small mammals while chainsaw milling is a more sustainable practice in Ghana

Abstract

Logging and mining are widespread in most West African countries and considering their socio-economic importance, little is known about their ecological impacts. In this study, we investigated the effects of chainsaw milling (logging) and artisanal mining on terrestrial small mammal communities in a tropical forest in Ghana. For this, we compared abundance, diversity measures and community composition of small mammals active at the forest floor in logged, mined and undisturbed forest sites. We found that abundance was higher in logged and undisturbed forest sites than in mined sites. Small mammal species richness, Shannon diversity and Pielou’s evenness did not differ significantly among the three forest disturbance categories. Community composition of small mammals varied between mined and undisturbed sites as well as between mined and logged sites, suggesting differential species responses to altered environments. This may be due to the presence of pits in mined forest sites, hence a reduction in exploitable ground habitat structures for shelter, nesting or food. Overall, our results suggest that artisanal mining has strong impacts on community composition of forest floor small mammals in tropical forests while the effect of logging by chainsaw milling activities is minimal, especially when practiced at low intensity. This effect was moderated by elevation and distance to streams that equally shaped small mammal communities. More research on the effects of specific forms of logging and mining activities on small mammals are urgently needed to better protect species in forests impacted by logging and mining.

Demography and reproductive seasonality of small terrestrial mammals in two forest ecosystems in Ghana

“…ARFR had the highest RDI in the wet season whereas BFR had the highest RDI in the dry season. The lack of seasonal variation has been reported in ARFR (Lawer et al, 2021) and other study areas (Teixeira et al, 2017) across Africa. The high RDI in the closed forest during the wet season may be attributed to available feeding material that comes with rainfall.…”

“…The study was carried out in the Atewa Range Forest Reserve (ARFR), which lies between latitudes 6° N and 6°20′ N and Longitude 0°30′ W and 0°30′ W, and the Bimpong Forest Reserves (BFR), which lies between latitude 5°30′ N and 5°45′ N and Longitude 1°19′ W and 1°35′ W. These two reserves are located in the Eastern and Central Regions of Ghana, and they are more than 100 km apart. ARFR is a Globally Significant Biodiversity Area covering a total area of 263 km 2 with average elevation of 507 m above sea level peaking at 842 m above sea level and a total area of 237 km 2 (Lawer et al, 2021). It is one of only two reserves in Ghana with Upland Evergreen Forests and is distinguished by outstanding species diversity and high levels of endemism in its distinctive habitats (McCullough et al, 2007).…”