Page:Territory in Bird Life by Henry Eliot Howard (London, John Murray edition).djvu/251

This page has been proofread, but needs to be validated.
COMPETITION BETWEEN GUILLEMOTS
193

vigilant in resisting - intrusion upon its few square feet as the Bunting is in guarding its many square yards, so that the evidence seems to show that that part of the inherited nature which is the basis of the territory is much the same in both species. What we have then to consider is. What is the biological value to the Guillemot of an inherited nature which, for the Bunting, has utility in relation to the supply of food for the young? Up to a point, the act of securing a territory has like value for each respective species, whether the area occupied be large or small—that is to say, it enables the one sex to discover the other with reasonable promptitude.

For the greater part of the year. Guillemots live at sea; singly, in twos or threes, or in small parties, they move upon the face of the waters, extending their wanderings far away from land, out into the broad ocean, where for weeks together they face the gales and heavy seas of the Atlantic. But in due course and in response to, internal organic changes, they return, like the Warbler, to their breeding grounds—rocky headlands or islands appropriately situated and affording the appropriate rock formation. During all these months of wandering, the majority seem to ignore the land, to pass away from it altogether, and to spread themselves over the surface of the ocean regardless of mainland or island. Some useful observations, which throw some light on the distance that Guillemots are accustomed to