Diel activity patterns and host preferences of Glossina fuscipes fuscipes (Diptera:Glossinidae) along the shores of Lake Victoria, Kenya

Abstract

Diurnal activity patterns and host preference of Glossina fuscipes fuscipes Newstead were studied in forest and linear habitats along Lake Victoria shore, Kenya. The objective was to identify the preferred hosts of G. /. fuscipes, the emanations of which may be attractive to this species. Hourly catches of flies in biconical traps were related to changes in the weather and the prevalence of hosts in the vicinity of traps. Flies were mainly active between 0800 and 1600 h, with males peaking around 1100 h and females around 1300 h. Activity of flies correlated directly with light intensity and temperature, but indirectly with relative humidity. Humans, livestock and the monitor lizard, Varanus niloticus, were the predominant hosts, although a significant positive correlation with fly catches could only be established with the prevalence of lizards. Blood meal identification by microscopic and serological methods showed that 73-98% of G. /. fuscipes fed on monitor lizards irrespective of host prevalence, season or location. The significance and possible epidemiological importance of the relationship between G. /. fuscipes and monitor lizards are discussed.

Detection of trypanosomes in small ruminants and pigs in western Kenya: important reservoirs in the epidemiology of sleeping sickness?

“…The existence of two species of tsetse flies, G. pallidipes and G. fuscipes fuscipes , which have different habitats, and feeding preferences, adds to this complexity. G. fuscipes fuscipes feeds primarily on the Nile monitor lizard, Varanus niloticus [25]. This probably prompted experiments that led to the isolation of T. brucei from one monitor lizard [26], but the ability of these cold-blooded reptiles to support trypanosomes, other than Stercorarian forms such as T. grayi remains unconfirmed.…”

Olfactory responses of Glossina fuscipes fuscipes (Diptera: Glossinidae) to the monitor lizard Varanus niloticus niloticus

“…Such biases in model catches of each sex could have been caused by several factors. Firstly, each sex might have responded differently to the electric net: comparison of actual and expected catches of a biconical trap surrounded by an incomplete ring of electric nets showed that about 45-78% of males and 27-51% of females avoided the electric nets (Odulaja & Mohamed-Ahmed, 1997). Male visual acuity may be superior to females, resulting in better avoidance of artificial objects (nets) and better detection of natural mimics (pipe models) when used alone.…”

“…Near Lake Victoria, Kenya G. /. fuscipes feeds almost exclusively on the Nile monitor lizard, Varanus niloticus niloticus Laurenti, (Mohamed-Ahmed & Odulaja, 1997), despite the widespread availability of other hosts such as humans, cattle, goats, sheep, dogs and donkeys. A similar high dependence of flies on monitor lizards has been observed in Uganda (Ian Maudlin, personal communication) and the Central African Republic (Gouteux et al, 1995).…”

A Low-cost Contamination Device for Infecting Adult Tsetse Flies, Glossina spp., with the Entomopathogenic Fungus Metarhizium anisopliae in the Field

“…A direct correlation between G. fuscipes catch and light intensity was reported by Mohamed-Ahmed and Odulaja (1997). No correlation was found between the time spent by¯ies in the Cd and the number of conidia that they picked up.…”