Land-use effects on avian diversity and community structure in agricultural landscapes of western Cameroon

Research on avian communities in Cameroon has focused on forests and savannas, leaving agricultural landscapes poorly studied. This study provides the first comprehensive assessment of bird diversity and community structure in the agricultural matrix of western Cameroon. From January 2022 to August 2023, 601 point counts were conducted across seven habitat types using the Point Abundance Index. Species richness and abundance were analyzed using negative binomial GLMs, while other alpha-diversity indices were assessed using non-parametric tests. Jaccard similarity was used to assess habitat overlap, and indicator taxa were identified using Indicator Species Analysis (ISA). A grand total of 26 345 bird detections, comprising 317 species, were recorded (70 families, 19 orders), including four threatened species: the Endangered African Grey Parrot Psittacus erithacus and three Vulnerable species (Abyssinian Ground Hornbill Bucorvus abyssinicus, Green-breasted Bushshrike Malaconotus gladiator and Bannerman’s Weaver Ploceus bannermani). Avian diversity differed significantly among habitats: agroforestry supported the highest richness and diversity, whereas tilled lands and pastures showed the lowest values. Forest patches exhibited high evenness, indicating balanced assemblages. The ISA isolated 76 significant species, confirming that assemblages are non-randomly structured across the landscape. Similarity analyses revealed strong species overlap among cultivated habitats, but lower similarity between forests and intensively managed farmlands. These findings highlight that agroforestry systems and remnant forest patches act as key refuges within agricultural landscapes. Maintaining a mosaic of forest and open habitats is essential for long-term bird conservation in western Cameroon.