Africanized bees in a metropolitan area of Brazil: shelters and climatic influences

Abstract

OBJECTIVE: Africanized bees are the most aggressive bees, form swarms several times a year and build their nests in a great variety of places different from European bees. This behavior brings them into closer contact with human populations, thus giving rise to a larger number of injuries. A study was carried out to gain greater knowledge on these bees' behavior and thus create more efficient strategies for dealing with them and educating the population on this regard. METHODS: Data consisted of 3,061 registries of requests to the Center for the Control of Animal Diseases of São Paulo for removing bee colonies and wandering swarms in the period between 1994 and 1997.An evaluation of the most frequent nesting sites and their correlation with climatic variables was conducted using Pearson's coefficient. RESULTS: There were 3,061 requests in the study period and the daily volume had a positive correlation with average temperature and degree of insolation and a negative correlation with relative humidity and rainfall. The colonies showed a likelihood for nesting in artificial constructions and the wandering swarms for nesting in trees. CONCLUSIONS: Those periods of the year characterized by high temperatures and low rainfall are related to greater activity of bees and a larger number of wandering swarms, thus giving rise to increased contact with human populations. Items such as boxes and oil-drums should not be left outdoors and ceilings and walls should be sealed off, as they are potential nesting sites for colonies and swarms. Wooded areas may harbor swarms, thus care should always be taken when in the proximity of such areas. No attempt should be made to handle swarms.