Attraction of Chironomus salinarius (Diptera: Chironomidae) to artificial light on an island in the saltwater lagoon of Venice, Italy.

The attraction of adult Chironomus salinarius to incandescent 3-W lamps of 7 different colors used in CDC traps was studied on a small island in the lagoon of Venice, Italy. An ANOVA indicated that the lamp type was a highly significant (P < 0.01) factor associated with differences in light trap catch (28% of total variation), as well as catch per lux (18% of total variation). The white lamp attracted higher numbers of adults than the other 6 color lamps. Yellow was the second most preferred, and red was the least attractive. There was a strong linear relationship (r = 0.93) between the catch and light intensity, which suggested that intensity was the primary factor influencing catch. However, catch per unit brightness (lux) tended to be inversely proportional to the peak wavelength associated with the lamp color (e.g., the violet lamp had the highest catch/lux, and the red lamp had the lowest). The corresponding regression model, Catch = 49 + [(48,013/lambda) - 63] . L, in which the slope associated with light intensity in lux (L) is inversely proportional to the peak wavelength in nm (lambda) explained 97% of the variation among lamp catch means. Manipulating light intensity and color could be useful to divert adult C. salinarius populations from midge-affected areas for control purposes.