Page:The British Warblers A History with Problems of Their Lives - 1 of 9.djvu/49

 It is difficult, for instance, to understand why in Italy and Hungary—countries affording natural features eminently suitable to its habits—the bird is scarce. The great plains of Hungary and the banks of the Danube always appear to me to be particularly adapted to it, yet I cannot believe that in a country where the natural life is studied with so great an interest the bird is overlooked. These remarks apply equally to the Netherlands, and to some extent Belgium.

The migration across Heligoland, where it occurs not infrequently in March, April, May, August, September and October, is completely at variance with the present knowledge of its distribution. According to Heinrich Gätke, the spring migration in Heligoland invariably proceeds from west to east; but in the case of this species, where? A glance at the map will show that we are here near 55° N. latitude, above which, until we reach 25° longitude, the bird can only be described as rare. Those individuals, therefore, that cross the island—and the evidence tends to show that their numbers are considerable—must, after leaving, turn southwards into Germany, or continuing east, use this as their route to the Baltic provinces and Central Russia. But the winter quarters, as far as we know, are in Morocco, Algeria and the South of Spain. Is it, then, conceivable that in order to reach its summer home it would traverse so great and unnecessary a distance? In the opinion of Heinrich Gätke, the majority of spring migrants from South Africa on their way to Siberia do not pass Heligoland, but go direct. It is probable, therefore, that there is much to be learnt concerning the northern breeding range.

Different species vary very considerably in character; some are lethargic and dull, others are the possessors of great nervous development, so that the study of some is more likely to lead to the solution of Nature's problems than the study of