From September 1997 to June 2000 148 scorpions (118 findings) from the province and city of Buenos Aires were sent to the INPB and the CeNDIE. The species involved were Tityus trivittatus (32/33 found in the city) and Bothriurus bonariensis (81/85 found in the province around the city). The population spontaneous report of both species increased from January 1999 to May 2000. The climatic, spatial and social variables that could be involved in these phenomena were analyzed. The influence of the media was essential for the 'peak' generation. However, the amount of findings or accident by scorpions, as well as the area of the city colonized by T. trivittatus, have shown a progressive increase during the last decades.