Scraping Sounds Produced by a Social Wasp (Asteloeca ujhelyii, Hymenoptera: Vespidae)


Fábio S. Nascimento, Departamento de Biologia, FFCLRP, Universidade de São Paulo, Av. Bandeirantes, 3900, 14040-901, Ribeirão Preto, SP Brazil. E-mail:


A distinct behavior performed by workers of the social wasp Asteloeca ujhelyii is described: guard waSPS, sitting outside of the nest around the entrance hole, scratch the nest envelope with their forelegs, thereby producing an audible ‘scraping sound’. Field observations revealed a relationship between the occurrence of the scraping behavior and the occurrences of waSPS entering and leaving the nest. The scraping was experimentally reproduced in the laboratory by moving a dissected wasp's leg parallel to the plane of the nest envelope. The resulting substrate-borne vibrations propagate very well over a distance of a few centimeters. The amplitude of these vibrations depends on the velocity of the scraping movements. The possible role of the scraping behavior in the waSPS’ communication is discussed.