The response of Simulium (Eusimulium) euryadminiculum Davies (Diptera: Simuliidae) to some olfactory and visual stimuli

Abstract

The response of Simulium euryadminiculum Davies towards silhouettes of different shapes and colors was observed, using an ether extract of the uropygial gland of the common loon to concentrate the flies in the experimental locality and "Tanglefoot" to trap the flies on the silhouettes. These simuliids were attracted primarily to the head–neck portion of duck decoys, most flies landing on the leeward side. The simuliids were attracted to the terminal (and most prominent) portions of artificial head–neck or cylindrical silhouettes; the distribution was not markedly influenced by the color of the silhouette. The number of flies attracted to three-dimensional targets was markedly influenced by color, black being the most attractive and white relatively unattractive. This selection of black by the fly may reflect its adaptation to the color of its natural host, the loon. Response of the flies to a two-dimensional (plane surface) target was essentially similar except that white was the most attractive color and black was relatively unattractive. Possibly this selection of white is associated with a resting response.