Published online by Cambridge University Press: 10 July 2009
In an attempt to define the favoured hosts of Culex portesi Senevet & Abonnenc and C. taeniopus D. & K., one bat, ten rodents, four marsupials, two birds and one crustacean, one amphibian and one reptile were exposed in groups of six in suction traps located in a forest in Trinidad. Each group of six baits included two white mice as a standard. The numbers of mosquitoes caught at each bait on three or six replicate exposures were analysed by an analysis of variance to separate population and site variations. Baits were then compared for ‘attractiveness’ by ranking according to an adjusted mean catch for each mosquito species. The proportion of each mosquito species that engorged on individual baits was also determined. In some cases, attraction and engorgement varied widely, and this was attributed to defensive action on the part of the bait animal. It was concluded that C. taeniopus was particularly attracted by the opossum Didelphis, which was superior to all indigenous mammals, while C. portesi was attracted to a wide range of rodents and marsupials. Neither was attracted by the cold-blooded animals. Both mosquitoes engorged well on the relatively insensitive marsupials with long bare tails, Dideiphis, Marmosa and Caluromys, and also on the well-furred but diurnal squirrel. Of the mainly nocturnal remainder, Culex portesi showed higher engorgement rates than C. taeniopus, suggesting a more aggressive or persistent feeding behaviour.