SEASONAL ABUNDANCE, BITING CYCLE AND PARITY OF THE MOSQUITO HAEMAGOGUS-LEUCOCELAENUS IN TRINIDAD, WEST-INDIES

Adult female populations of Haemagogus leucocelaenus (Dyar and Shannon ), the sylvan vector of yellow fever, were monitored weekly during 198 1-82 by human collectors on the ground at Point Gourde in Chaguaramas Forest, 16 km west of Port of Spain, Trinidad. Hg. leucocelaenus showe d only diurnal landing activity, from 06.00 to 18.00 hours (sunrise to sunset, universal time), with a single peak of activity between 10.00 and 14.00 hours. Densities of Hg, leucocelaenus during the wet season (May-November) were about double the level recorded during the dry se ason (December-April). Monthly parous rates averaged 53.9% (range 25-9 0%) and some females were up to five-pars. Retained eggs (range 2-6, m ean 4/female) were found in the ovaries of 0.34% of landing females, a ll of which had stage 1 ovarian follicles for the next gonotrophic cyc le. Therefore blood-feeding is not inhibited by egg retention. Hg. leu cocelaenus vector potential is reappraised in the light of these findi ngs.