PRODUCTIVITY OF CONTAINER-BREEDING AEDES- ALBOPICTUS IN AN URBAN-ENVIRONMENT

Introduction Aedes albopictus has been found at Cananeia city in the S outheastern State of S. Paulo, Brazil. A study was carried out to eval uate the productivity of its breeding place. Material and Method A con tainer classified as large and permanent was chosen. Water had accumul ated at the bottom and was rich in organic matter mainly of vegetal or igin. From November 1996 until May 1997, fortnightly observations were perfomed, sampling immature stages found in a seventh parr of the con tainer's total water volume (nearly 70 litres). Pupae were collected, identified and sexed. The productivity of the breeding place was estim ated using Focks et als. (1981) formula adapted for a single large con tainer At the same time adults were caught by using human bait and the aspiration of resting places. The first catch was performed at six me ters from the breeding place studied. Williams' mean was calculated fo r the human bait and mean hourly density for the aspiration results of the resting places (Subbarao et al., 1988). Results Immature stages o f Ae. albopictus represented 44.9% of the total collected through fift een fortnightly regular samplings (November 1996 to May 1997). The pup ae mean was 31.13 and so the emergence index was 2.1. Multiplied by se ven the result was 14.7 as the estimated mean number of females per da y produced in that container Adult females caught on human bait Rave a general Williams' mean of 30.7, while the mean hour by density was 9. 2. According to the accumulated calculated adult number, 22.8 females per day were available to seek human bait, under the conditions of the observations performed. Discussion Counting pupae is an efficient met hod of estimating the productivity of the breeding place of Ae. albopi ctus. The richness of the organic matter in the water in the container made it quite inappropiate to establish comparisons with water reserv oirs for domestic use. Nevertheless, a lack of or deficient maintenanc e approximate these containers to the one here studied. So cleaning is an important factor and it must be emphasized as necessary to prevent the installation of mosquito breeding. Though if is a distinct specie s it is reasonable to expect that the application of these study metho ds to Ae. aegypti would be useful in the attempt being made to erradic ate this latter species from our country.