Does Fire Exclusion Impact Insect Communities? An Insight with Ants in Three Habitat Types from Lamto Scientific Reserve, Côte d'Ivoire, West Africa

Abstract

Vegetation fires remain one of the primary causes of habitat degradation and biodiversity loss in tropical forest-savanna mosaic ecosystems. However, their impact on certain components of biodiversity is often understudied, especially when fire is excluded from a given ecosystem for extended periods. This study aims to evaluate the effect of long-term fire exclusion on ant communities across three distinct habitat types within the Lamto Scientific Reserve, Côte d’Ivoire. Ants were sampled from January to May 2022 using standardized methods of Ant of Leaf Litter (ALL) protocol, soil monoliths and tuna lures. The study yielded 82 ant species belonging to 32 genera and 7 subfamilies including Amblyoponinae, Dolichoderinae, Dorylinae, Formicinae, Myrmicinae, Ponerinae and Proceratiinae. Results showed a strong variation in ant species between the three habitat types (X2 = 28.57, df = 8, P= 0.001). The ant species richness was higher in annually Burned Savanna (47 species) than Gallery Forest (40 species) and Unburned Savanna (29 species). A dissimilarity in ant species composition was observed between three habitat types (ANOSIM:  R = 0.56, df = 2, P= 0.014). However, Gallery Forest and Unburned Savanna were more similar (ANOSIM:  R = 0.07, df = 1, P= 0.40) than annually Burned Savanna. This study provides a baseline dataset on ant community of an understudied habitat. It demonstrated that ant communities of this savanna excluded from fire tend to be similar to ant communities of Gallery Forest. Although this study provides valuable information on the effect of long-term fire exclusion on ant communities, it is necessary to conduct further studies integrating other insect taxa to have a better understanding and reinforce knowledge on the effect of long-term fire exclusion on insects and biodiversity.