Needles of Pinus sylvestris and P. contorta as food for captive capercaillies (Tetrao urogallus): Preference tests and analyses of needle chemistry

Abstract

Toward the end of the 1960s, commercial plantations of the North American lodgepole pine (Pinus contorta) were established in the Fennoscandian boreal forest region. In a food selection test, 8 captive male capercaillies (Tetrao urogallus), which utilize native Scots pine (P. sylvestris) as their main food resource within the region in winter, were provided with needles of both pine species ad libitum. Needles of the two species were consumed in about the same amounts, although they differed in terms of their concentrations of compounds such as nitrogen, phenolics and resins, which all have the capacity to influence feeding by browsing herbivores. By artificially increasing resin concentrations in the food, total consumption by the capercaillie was reduced significantly.