Relative Abundance of Tabanids in the Savanna Regions of Côte d'Ivoire

Abstract

Tabanids were caught with Nzi traps to study their presence, abundance, seasonal variation, ecological preferences and species diversity. The study was conducted over four seasons in four habitats (savanna, forest, gallery, and corral) in four townships in the main two livestock departments of North and Northwest Ivory Coast (Odienne and Korhogo). Out of 3104 caught specimens, 4 genera and 16 tabanid species were identified. The most abundant of caught species were Tabanus taeniola Palisot de Beauvois, 1807 (26.4%), T. par Walker, 1854 (15.6%), T. laverani Surcouf, 1907 (14.9%), and Chrysops distinctipennis Austen, 1906 (12.3%). The least abundant species were Atylotus albipalpus Walker, 1850 (6.9%), Chrysops longicornis Macquart, 1838 (6.9%), T. brumpti Surcouf, 1907 (4.8%), T. gratus Loew, 1858 (3.7%), At. agrestis Wiedemann, 1828 (2.5%), At. fuscipes Ricardo, 1908 (1.8%), Ancala necopina Austen, 1912 (1.5%), T. biguttatus Wiedemann, 1830 (1.4%), T. ricardea Surcouf, 1906 (0.5%), T. boueti Surcouf, 1907 (0.4%), T. pluto Walker, 1854 (0.3%), and An. fasciata Fabricius, 1775 (0.2%). The largest numbers of tabanids were caught in the gallery, and the fewest in the forest. There were more catches in the Odienne department than in that of Korhogo. An abundance peak occurred in March during the hot dry season, except for Korondougou township, where a peak occurred in June during the rainy season. In addition, 2471 Stomoxyinae were captured: Stomoxys niger Macquart, 1851 (70.7%) and S. calcitrans Linnaeus, 1758 (29.3%). The Stomoxyinae, represented by two species only, made up about 45% of the biting flies captured. They will have to be reckoned with when evaluating the impact of biting insects on cattle.