The impacts of human activity on mammals in a community forest near the Dja Biosphere Reserve in Cameroon

Abstract

Human activity in African tropical rainforests continues to threaten wild mammals. Many rural communities are dependent on hunting, yet there is a widespread lack of baseline data on ecology and the sustainability of hunting. We investigated the impacts of human activity on mammal species composition and distributions within a community forest surrounding a village in the buffer zone of the Dja Biosphere Reserve in south-east Cameroon. We conducted a camera-trap survey in August–November 2017 and detected 24 mammal species, including Critically Endangered western lowland gorilla Gorilla gorilla gorilla, Endangered central African chimpanzee Pan troglodytes troglodytes and Endangered tree pangolin Phataginus tricuspis. We used occupancy analysis to explore relationships between indicators of human activity (distance to a road and the Reserve), habitat quality (distance to the river and tree cover) and the distributions of species. We found that the local distribution of threatened mammals was not apparently limited by human activity, and proximity to the road did not negatively influence occupancy for any species. However, most of the Reserve's large species were not detected, including the African forest elephant Loxodonta cyclotis and the largest ungulates, and the occupancy of two species commonly hunted for wild meat was positively correlated with distance from the village, indicating hunting may be unsustainable. Our results show that the community forest provides habitat for threatened species outside the Reserve and in close proximity to people. However, effective conservation management will require continued monitoring and research to determine whether current rates of hunting are sustainable.

Fruit Availability Influences Forest Elephant Habitat Use in a Human Dominated Landscape, Campo-Ma’an, Southern Cameroon

“…In southeast Cameroon, Dancer (2019) found that parks are targeted by poachers; the lack of funding usually does not allow for permanent surveillance by rangers compared to FMU. Therefore, the lack of detection of forest elephants in community forests which is part of the CL in the southeast of Cameroon as reported by Tudge et al (2022), suggest that, compared to our study area, the pressure on forest elephants might be low enough to allow them to occur in all land use types. Also, forest elephants were detected at least once every month in each land use types.…”

“…Camera trap photos were date and time stamped. We used an independence interval of 30 min for species at the same camera trap station (Chakraborty et al, 2021; Deith & Brodie, 2020; O’Brien et al, 2003; Tudge et al, 2022). Photos with multiple individuals of the same species at the same camera trap station on the same time frame was considered a single detection event (Chakraborty et al, 2021).…”

High diversity and sharing of strongylid nematodes in humans and great apes co-habiting unprotected area in Cameroon

“…The forest is degraded, and fragmented, as intense logging, hunting and crops occur in the area (Arlet & Molleman, 2010; Ávila et al, 2019; Betti, 2004; Tagg et al, 2018). Based on previous studies from different localities, we assume that the agricultural fields in Dja can attract animals (such as chimpanzees), resulting in crop-raiding with defecation (Arlet & Molleman, 2010; Tudge, Brittain, Kentatchime, Kamogne Tagne, & Rowcliffe, 2022). Local people often walk barefoot through Dja agricultural fields and eat crops straight from the ground without previously washing them (Table 3) .…”

Power to the people: Analysis of occupancy models informed by local knowledge

“…As such, we determined that gathering presence–absence data at a 1 km 2 site resolution would allow the most informative comparison. Since the home ranges of the larger species in our study area are typically larger than 1 km 2 , we interpreted occupancy as the proportion of sites used by a species (MacKenzie et al, 2006; Tudge et al, 2022).…”

“…As such, we determined that gathering presence-absence data at a 1 km 2 site resolution would allow the most informative F I G U R E 1 Location of the Dja faunal reserve and approximate location of the study village in southeastern Cameroon, with surrounding production and community forests comparison. Since the home ranges of the larger species in our study area are typically larger than 1 km 2 , we interpreted occupancy as the proportion of sites used by a species (MacKenzie et al, 2006;Tudge et al, 2022).…”