The Mosquitoes of Bwamba County, Uganda VIII.—Records of Occurrence, Behaviour and Habitat

Abstract

At the time of writing, 1949, field work on mosquitoes has been carried on in Bwamba County, western Uganda, for a period of ten years, with very few intermissions. The topography and vegetation of this area have been described elsewhere (Haddow, 1945a). The main effort has centred round the search for forest vectors of yellow fever, but much work has also been done in native plantations, huts, etc. While genera such asAëdes and Taeniorhynchus have, inevitably, required special attention, records of all mosquitoes encountered have been kept throughout the investigation, whether or not they seemed likely to be involved in the local epidemiology of yellow fever. Certain sections of the work have already been published (Mahaffy & others, 1942; Haddow, 1945a, 1945b, 1945c, 1946 and 1948; Haddow & others, 1947; Haddow & Dick, 1948; Haddow & Mahaffy, 1949), but a great part of it has not as yet been submitted.

Mosquitoes of Western Uganda

“…perfuscus, which made up 50.7% of the mosquitoes collected (Table 2). This differs from previously published collection records for this area that reported that the most frequently captured species were Aedes (Stegomyia) africanus (Theobald), Mansonia (Mansonioides) africana (Theobald), and Anopheles (Celia) gambiae (Giles) (Haddow 1945b;Haddow et al 1947Haddow et al , 1951Haddow and Mahaffy 1949). However, these previous studies used human-baited collection methods that would not have attracted the nonanthropophilic Cx.…”

“…In November 2008, this species made up 78.6% of the Sempaya collection, Mattingly (1957) and a more detailed description has subsequently been published by Huang (2004). Therefore, it is possible that the Aedes (Stegomyia) aegypti (L.) listed in Bundibugyo District (Bwamba County) (Haddow 1945b;Haddow et al 1947Haddow et al , 1951Haddow and Mahaffy 1949) included Ae. aegypti formosus because these subspecies are morphologically very similar and no formal description was available at the time of the collections.…”

“…Nearly all of the mosquito species collected in Sempaya had previously been listed in Bundibugyo District by Haddow et al (1951), suggesting little change in the mosquito fauna of the area in the past 60 yr. As mentioned above, the method widely used to collect mosquitoes in Uganda from the mid-1930s to the early 1970s was human-baited catches and therefore, in contrast to our collections, the most abundant mosquito species reported in Bundibugyo District at that time were the highly anthropophilic Ae. africanus, An.…”

“…The tubed mosquito samples were kept frozen either on dry ice or in liquid nitrogen dry shippers until shipped to the CDC laboratory in Fort Collins, CO, for identiÞcation and processing (CDC 2012). At the CDC, the mosquitoes were identiÞed to species on the basis of morphological characters by using the keys of Edwards (1941), Jupp (1996), Gilles and De Mellion (1968), Gilles and Coetzee (1987), and Huang (2004), supplemented with notes by Haddow et al (1951), Gillett (1946), Corbet (1958), and Gillett (1972). Voucher specimens for each species were kept for future reference and for identiÞcation consultations.…”

Sampling Adults by Animal Bait Catches and by Animal-Baited Traps

“…The capture of unfed females that have either alighted on, or are hovering around, the bait is commonly taken as showing that they have been attracted for the purpose of taking a blood-meal, but this may not always be true. Uranotaenia, Ficalbia and Hodgesia species are sometimes caught at bait (Haddow et al, 1951;Macdonald, 1957;Mattingly, 1949b), but there is often no clear evidence that they would bite if given the opportunity. In Canada, Hocking et al (1950) and Haufe (1952) recorded separately the landing and biting rates of Aedes species attracted to man, and Haddow & Ssenkubuge (1963) emphasised the importance of distinguishing between these two phenomena, i.e.…”