Page:Bird Haunts and Nature Memories - Thomas Coward (Warne, 1922).pdf/269

Rh results?—the destruction of the native fauna or the colonists' stock, but not of the prolific alien.

Later enthusiasts have brought us the little owl and grey squirrel, and we have yet to see the full results of the folly of introducing successful colonists. At Woburn already it has been necessary to have a squirrel drive, and though neither squirrel nor little owl may be guilty of all the crimes laid to their charge, it is certain that as both are rapidly spreading some other creatures are suffering. l have heard complaints from Hertfordshire and Northants, where the little owl flourishes, that the tawny and barn owls are decreasing; there is only a certain catchable quantity of owl food, and the smart little owl is getting the pick. The bird has now reached our area, where during the last ten years or so the barn and tawny owls have increased; what will the next decade show?

There are many introductions for which we are not intentionally responsible, creatures which travel with and in our food supplies. Many of these come merely as stowaways and perish in an inhospitable land, but others, the hangers-on of civilisation, follow man wherever he takes or sends his supplies. The codlin moth, estimated to cost America at least £2,000,000 annually, we sent from Europe, and in return we have to thank America for the American blight. Cockroaches travel from various parts of the world, for they are great navigators, and colonise wherever they land. The Mediterranean flour moth is everywhere, its land of origin is uncertain, and that small weevil, Calandra granaria, is a similar cosmopolitan pest. These and many others, too numerous to mention, increase and spread as trade increases and spreads. We must investigate their life story and take whatever course we can to reduce them to their original status.

Having realised that man not only has been, but still is, responsible for great changes in animal life, many of which