Taste preferences and feeding behavior in nine-spined stickleback (Pungitius pungitius) in three geographically distant populations

Abstract

Taste preferences of classical taste substances (10% each sodium chloride, calcium chloride, and sucrose; and 5% citric acid), and 21 free amino acids (L-isomers, 0.1–0.001 M) and feeding behavior of the nine-spined stickleback Pungitius pungitius belonging to the populations of the Moskva River (Caspian Sea basin), Lake Mashinnoe (White Sea, Kandalaksha Gulf), and Bol’shaya River (Western Kamchatka, Okhotsk Sea) are determined. It is proven that the spectra of taste preferences are similar in different stickleback populations. For sticklebacks in all three populations, citric, aspartic, and glutamic acids are mostly palatable. The maximum number of palatable amino acids (16) is found in sticklebacks from the Moskva River. Sticklebacks from the White and Okhotsk seas prefer the lower number of amino acids, 10 and 4, respectively. Deterrent amino acids are not found. The gustatory amino acid spectra of sticklebacks from different populations are positively correlated (p < 0.05). Sticklebacks from the Sea of Okhotsk relatively rare taste the offered food objects again (agar–agar pellets with the studied taste substances). Such behavior is more common in sticklebacks from the White Sea, and those from the Moskva River have an intermediary position. The manipulation activity in the compared fish is associated with the hydrology of the water bodies. In ninespined sticklebacks from all three populations, the actions performed upon intra-oral testing of a food object follow two alternative behavioral stereotypes. The stereotypes of swallowing and of rejection of food differ slightly between the populations and depend on the palatability of the offered object.