Islands are good locations because the eggs are safe from mammalian predators like raccoons and skunks as well as pet dogs and cats. Being close to the water allows adult loons to slide off the nest when danger approaches and swim back underwater, popping up just at the nest's edge. This is a good way for loons to avoid catching the attention of flying predators like gulls and crows. The best nest sites also include some overhead cover to hide eggs from the eyes of avian predators, and shelter from wind and waves. If a loon pair loses an egg or chick to predation, they make a replacement nest in a new site.
Loons work on building their nests all through incubation, and nests are often used over again.
Platforms are made of cedar logs and buoyant material and covered with ample soil and vegetation for nest-building. Dr. Walter Piper has studied the effect of artificial nesting platforms on the reproductive success of loon pairs. Our results show clearly that loons find the platforms attractive as nesting sites and that platforms boost reproductive success by about 100 percent. In one case, a new platform even induced loons to breed on a small lake with no previous record of loon breeding. Hence, nesting platforms seem a possible means of mitigating the negative effects of shoreline development and human recreational activity on loon populations.