THE STARLING

Nelson Evening Mail, Volume LXI, 7 August 1928, Page 8

THE STARLING

IS IT INJURIOUS?

Myriads of starlings fly over this district morning' aucj evening. For this reason special interest attaches to the' appended article by B.'H.'D. Stidolph, 8..A.0.U-, iu "The Post. 1 ' .'.-.. ' The starling in New'Zealand is gen-erally-looked upon as a beneficial species, "but no scientific investigation of its economic status iu this country has been carried out. In England it was for many years looked upon as one of the most useful of wild birds, latterly there has been a gradual change of "opinion that it has become one of the most injurious. Its .alarming increase iu the British Isles threatened the cereal and fruit crops. Accordingly a critical investigation of the bird's food was made by Dr. Walter E. Collinge, F.L.S. In 1919 it was stated that'the starling appeared a most serious menace to the production of homegrown food and any further increase in its numbers could only be fraught with the most serious consequences. By 1921 ,the starling had undoubtedly increased to such an. extent and the damage done to crops was so great that farmers ami fruit growers iu all parts of the country realised the seriousness of this bird plague; The causes which brought about the change in the food habits of the starling were not at first apparent, but a closer study of its habits readily explained the deflection. The remarkable increase iu the starling's numbers, Hi Dr. Collinge's opinion, was brought about, firstly, to the security of its nesting site;'secondly, to the change in its food habits; and thirdly, to the autumnal migration. Its habit of moving about in flocks during certain months of the year constitutes a grave clanger, and another habit of collecting at special roosts frequently causes much, damage- As the number of starlings has increased annually iu tho British Isles a gradual change in the nature ol the food consumed by these birds has taken place. There was fairly reasonable evidence, states Dr. Colhnge, to show that in the past the bulk of the food consisted of insects and insect larvae, slugs, snails, earthworms, millipedes weed seeds, and wild fruits; in more recent years this has been supplemented by cersals and cultivated fruits and roots. Some writers have affirmed that once tho fruit-eating habit is acquired it refuses other available food. LOSS TO THE CULTIVATOR During an investigation extended over two years Dr. Collingc visited many farms' to investigate the damage caused to newly-sown cereals. In some cases as much as thirty per cent, of the seed was eaten. The loss due to vesownig, where possible, is very grcat> if the ugh cost of labour is taken into consideration, but where this is not possible it is a direct and enormous loss to the cultivator and to the nation. Again, in fruit growing districts the depredations of this bird become more marked annually. Cherries, strawberries, currants, plums of all kinds, and more recently apples and pears suffer. In order to appreciate clearly the true economic position of the starling an examination was made of tho stomach contents of a large series of individuals from various districts and during each mouth of the year. As a result it was found that 51 per cent, of the food consumed in the year consisted of animal matter and 49 per cent, of vegetable matter. A total of 36.5 per cent, of the starlings' food, as the investigation indicated, constituted a benefit to the agriculturist, 41 per cent- .an injury, and 22.5 per cent, of a neutral nature. NATURE OF FOOD-

The above food, examined in further detail, showed that the animal matter contained 26.5 per cent, of injurious insects and their larvae, 3.5 per cent, ot neutral insects, 2.5 per cent, of beneficial insects, 8.5 per cent, of earth- ' worms*' 6.5 per cent, of slugs and snails, 1.5 per cent, of millipedes, and 2 per cent, of miscellaneous animal mat ter. A total of 20/5 per cent, ot the vegetable matter consisted of cereals, 2 5 per cent, of cultivated roots and leaves, 15.5 per cent. : of cultivated fruits, 7 per cent, of wild fruits and seed*, of weeds, and 3.5 per cent, of miscellaneous vegetable matter of a neutral nature. It was found that the percentage of animal matter was greatest in April, May, and June, the highest percentage of fruit was in July, August, and September, and the highest percentage of cereals in September, October, and March. In some districts the total percentage of injuries during the mouth July to October was nearly 100-cereals and cultivated fruits formed the main items of food during that period of the year. It is rather difficult to balance these figures, but Dr. C'ollingc, after very careful analysis, considered that the starling, for a period of about three months, was wholly beneficial, for another three months it was partly so, and for the remaining six months it was harmful. A point in tho starling's favour, he said, was the nature of the food hrought to the nest by the parent birds during the nesting soason. A volumetric analysis of the stomach contents of 40 nestlings showed that injurious insects constituted 89 per cent, of the total bulk of food, neutral insects 1.5 per cent., earthworms and slugs 6.5 per cent., and miscellaneous matter 3 per cent. In addition to feeding the growing and rapacious nestlings upon this diet, there was every reason to suppose that during that period the parent birds also lived on a similar diet. FRUITGROWERS SUFFER Dr. Collingo goes on to state that :cvery farmer in< England is aware of the damage done by. these birds to autumn and spring sown cereals. Iu many cases great loss is occasioned by the 'rooting up of seeds which are not consumed. In a like manner the fruit grower can recount serious damage to strawberrv, raspberry, gooseberry, currant, cherry, plum, pear, and apple crops. Examined from almost any standpoint the unprejudiced mind can only come to one conclusion, viz., that the starling has long since risen above the "high water mark of abundance, and iu consequence is doing more harm than good. Iu other words, too many specimens of one species require the. same kind of food within a limited area. In view of these findings of tho starlings food in the Old Country, it is well to keep tho starling in New Zealand .under a watchful eye.