Whistles of beluga whales in the reproductive gathering off Solovetskii Island in the White Sea

Whistles recorded in a reproductive gathering of beluga whales near Solovetskii Island in the White Sea are analyzed. On the basis of the absolute characteristics and shape of the frequency contour, whistles are classed into 16 types. Whistles belong to a relatively low frequency band, contain many harmonics, and have a simple shape of frequency contour. The average whistle duration varies from 0.1 to 1.7 s for different types, the average value of the maximum fundamental frequency varies from 1.4 to 4.5 kHz, and the average number of inflection points is from 0 to 9 per signal. In contrast to other populations, where flat whistles are the most frequent vocalizations, beluga whales observed in the reproductive gathering in the White Sea most often produce short whistles with a V-shaped frequency contour.