The spot on the islet where the loons had their nest was almost unconcealed. It was in a grassy cup within four or five feet of the water's edge, and sheltered only by a thin screen of bushes on the landward side. Toward the sky it was quite open. There had seemed to be little need of concealment before the intruder, man, came to the lake. The islet was too far from the main shore to be in danger from the visits of foxes or bears, fishers or raccoons. And as for the sky--well, the loon had little fear of anything that flew. Because of this lack of apprehension from skyward, even his coloring was not very protective, his glossy black, barred and mottled with pure white, being fairly conspicuous against the grays, and greens, and browns which surrounded the nest. Neither he nor his mate had any particular objection to being seen by any marauder of the air. Even the murderous goshawk, or the smaller but even more fearless duck-hawk, would know better than to swoop down upon the uplifted dagger of a nesting loon. And as for the eagle, though doubtless strong enough to master such an antagonist in the end, he is wise enough to know that the loon's punishing beak and bulldog courage in defence of the nest would make the victory an expensive and painful one.
But there was one enemy besides man whom the loons had cause to fear, even on their secluded islet. They hated the mink with a well-founded hate. He could easily swim out to discover and rob their nest; and if he should find it for a moment unguarded, his agility would enable him to keep well clear of their avenging wrath. On the nest neither male nor female feared to meet the mink's attack, their lithe necks and unerring quickness of thrust being sufficient defence even against so formidable a robber. But their movements on land--an awkward, flopping series of waddles--were so slow that, in the case of a mink arriving, the precious eggs would be safe only while actually covered. A big mink had been seen that very morning, prowling down the opposite shore, and both birds were uneasy. They seemed now to be taking counsel upon that or some other equally important matter.
For the next few days, however, the life of the loons was tranquil, with good fishing to content their appetites and no untoward event to make them anxious. Then came a day when the patient mother on her nest could not conceal her happiness and her excitement, when the male, forgetful of meals, stood for hours at a time in interested expectancy beside the nest. The strong chicks within the eggs were beginning to stir and chip the shell. It was not the day that the big mink should have chosen for his expedition to the islet.