Vibrational background noise in herbaceous plants and its impact on acoustic communication of small Auchenorrhyncha and Psyllinea (Homoptera)

Vibrations induced in plant stems by rain drops, wind, and mechanical activity of insects were studied under natural conditions. Wind and rain can induce high-frequency vibrations in the range up to 3–4 kHz and jamming insect signals completely. For this reason, small homopterans mostly emit their signals during the gaps between gusts of wind. In the regions where strong wind blows during most part of the day, they concentrate mainly in the places protected from the wind (dry river beds, hollows, and other depressions of the relief). Individuals of different species occurring on the same or neighboring plants usually sing alternately, i.e., demonstrate the same response to each other’s signals as to the wind-induced noise. Low-amplitude vibrations resulting from insect movements have no considerable impact on vibrational communication of Homoptera.