An ecological study of mosquitoes in the area of Pinawa, Manitoba, with special reference to the distribution and abundance of the genus Aedes

Abstract

In Winnipeg, the developmental sites of pest mosquito larvae are localized and in close proximity to potential hosts. This discovery motivated a study of the distribution and abundance of both larval and adult mosquitoes at Pinawa, Manitoba. If pest mosquito developmental sites were found to be localized and predictable, source reduction of pest mosquitoes, the control method being developed in Winnipeg, might be applicable. At Pinawa, the density of mosquito larvae generally increased with increases in the amount of vegetative cover. During the 1971 season almost all mosquito production took place in the early spring and was the greatest per unit area in the most densely vegetated areas. Certain species of mosquito larvae were associated with areas of particular degrees of vegetative cover. Studies of adult mosquitoes revealed that as the amount of vegetative cover increased, the numbers of mosquitoes captured in CO2-baited traps also increased. Some mosquito species were associated with open areas and others with wooded habitats. Collecting mosquitoes as they attempted to feed on man in a recreational area of Pinawa showed that pest mosquito abundance was greatest in the early spring when Aedes abserratus, Aedes intrudens, Aedes communis, and Aedes punctor were most abundant. Aedes implicatus comprised large proportions of spring mosquito larvae populations in almost all areas examined but it was not taken attempting to feed on man during 1971.