IN THE FIELD OF SCIENCE.

Southland Times, Issue 21193, 20 September 1930, Page 8

IN THE FIELD OF SCIENCE.

A THRIFTY VEGETARIAN. Dr IV. E. Ritter, Professor of Zoology at the University of California, is publishing the results of several years’ labour on the acorn-storing woodpecker of California. A brief forerunner of his most fascinating account may be offered. The Californian woodpecker, like most of its numerous tribe, sits upright on the side of a tree — reminding one of the hardy souls who repair our telegraph wires—and ceaselessly taps the bark. Most woodpeckers operate in order to detect and extract the many insects tunnelling or hiding beneath the tree's outer crust.

Not so, however, the acorn-storer, who is a vegetarian. He has his favourite kind of acorn and his favourite trees, and he im serfs the one into deliberately drilled holes ready-made fissures of the other. Whole woods may be found with the tree trunks literally peppered with acorns, which fit neatly in the holes or tuck snugly in the deep furrows of the bark. When times are hard the bird reappears at one of these acorn stores and takes his fill.

Like another harvester, the grey squirrel, he has a poor memory and makes many foolish mistakes. He will make a cache in the side of a house and cram it with food that falls through on the other side, or at great cost of labour store nuts too hard to open. Still, his thrifty instinct has caused him to flourish where others must decamp when winter comes, and he is consequently five times as numerous as any of his insectivorous relatives sharing the same woodlands.

It may be mentioned that the English nuthatch, a tolerably common resident, though feeding chiefly on insects during the summer, in the autumn lives largely on cobnuts. These it wedges neatly in a bark fissure, and then, clinging to the tree trunk, delivers sledge-hammer blows with his beak, pivoting from the hips like the expert golfer, so as to obtain the full weight of the body behind the blows.