PROBLEMS CONCERNING PREDATION

Forest and Bird, Issue 57, 1 August 1940, Page 1

PROBLEMS CONCERNING PREDATION

Error —Please read Mrs. Partington for Mrs. Parkinson.

Editorial •

C/'h TEDIOUS and slow method of exterminating a species is to destroy its natural enemies, y4-l i.e., its indigenous, not the imported or unnatural enemies. The natural enemy has lived J in association with its prey for ages upon ages, . without in any way impairing the numbers thereof, but having quite the opposite effects as even with the aid of its vigilant eye and guarded approach it is unable to catch the virile, wary and well fed individuals. The wounded, the starving and the diseased creatures are those which, being the most easily caught, are preyed upon. It must therefore be obvious that the natural enemy is nature’s tool for maintaining the virility and thus the increase of a species. Biologists and ecologists recognise this fact, yet, the world over, we have the hunter, and the fisherman too, endeavouring to increase the numbers of creatures which they themselves wish to have the pleasure of killing by waging war on natural enemies (such as hawks and shags) which are the natural enemies of rats, mice, etc., and of eels, etc., respectively. In New Zealand, when one considers the vast numbers of cats, rats, hedgehogs, weasels, etc., that now roam the land, the efforts of those charged with the administration of game and fishing interests in the field to wipe out all natural and unnatural enemies read something like the well-known story about that good woman, Mrs. Parkinson. Rats, by the way, are scarcely ever mentioned, perhaps because it is not realised that while they are probably the most potent and most numerous of unnatural enemies of birds they are also the favourite prey of the harrier hawk. The story to which we refer, relating to Mrs. Parkinson, is well known and relates how this good housewife, the mother of several sturdy fishermen, lived on the Atlantic coast of England. She was scrupulous in house matters, so much so that the removal of her sons’ boots was insisted upon before they entered the home. Her broom and mop were ever in evidence. One day, however, a great storm arose and swept the angry Atlantic billows far inshore and into her house. Mrs. Parkinson promptly seized her trusty mop. What for ? To sweep back the Atlantic Ocean. A similar procedure seems to be evidenced when steps are instituted with a view to killing out cats, rats, hedgehogs, and the like. The whole country is over-run with such acclimatised unnatural enemies and the power of an autocrat with the means of the Bank of England behind him might be insufficient to combat the invaders. How then can the problem be dealt with ? Let us turn our attention to natural, not unnatural and therefore unsafe, methods. Good soil produces most things that are good for desirable wild life and for ourselves. Poor soil, the result of erosion following forest mismanagement, produces a weed flora and fauna. Native vegetation growing on strategical areas to resist excessive water run-off is the only apparent means of widespread soil improvement. At the same time a few closed seasons in shooting, if not in fishing as well, accompanied by a largely “let alone” sort of policy would give nature an opportunity of re-adjusting matters in a degree, especially if nature’s efforts were helped from all sides by a more than usually well thought out plan, such as the establishment of efficiently managed sanctuaries and inviolate refuges. But let the policy be firm against any further violent disturbances in nature such as. result from efforts to establish foreign feral creatures. To read the story of past successfully acclimatised wild life is to ready a story of disaster. In a large number of instances where some mammal, plant, insect, or bird has been purposely introduced it has later been declared a pest and had war waged on it; yet to-day many still pin their faith on the old methods of blind acclimatisation and transference of species from one locality to another. Evidently the desire to acclimatise is still unsatiated despite the grievous harm done by rabbits, deer, cats, rats, weasels, and goodness knows what else.