Bud‐eating by bullfinches, Pyrrhulapyrrhula in relation to the chemical constituents of two pear cultivars

Publisher Website
Google Scholar
Abstract
SUMMARY: Damage to pear trees of the cultivars Conference and Doyenne du Cornice caused by Bullfinches feeding on the flower buds was measured during January‐April 1981. Bud‐eating was concentrated on trees near woodland, and occurred at a steady rate within each row, though progressively more rows were attacked. Levels of total soluble protein, free amino acids, starch, glyeeride‐glycerol, fructose, glucose and phosphorus were low until mid March, when the amounts per bud (and concentrations of starch and total soluble protein) rose sharply, coinciding with an increase in the size of buds. Sucrose did not occur at detectable levels. Conference buds contained significantly higher concentrations of fructose and free amino acids than Cornice. The implications for understanding bullfinches' bud‐feeding habits are discussed.