The highpoint of my recent trip to visit my family in Northern Germany was a visit of the North Sea island of Helgoland. The seaside cliffs along the high plateau almost 200 feet above sea level serve as breeding grounds for northern gannets, common murres and black-legged kittiwakes. Walking along the rim of the cliffs on a bright windy day I was looking down on thousands of birds nesting on narrow ledges.
Northern gannets are using brightly colored nylon fishing nets for their nests. I wasn't aware of the deadly consequences until I scrutinized my photos and was horrified to discover dead birds, broken bones, beaks and flight feathers trapped in the tangled flotsam, wherever I looked. These synthetics are indestructible and do not disintegrate no matter how long exposed to light, air or water.
Abandoned or lost nets are a horrific problem in the world's oceans. Such "ghost" nets suspended in the oceans like curtains and stretching over miles of ocean floor will keep on fishing, and trapping and killing marine life, for years to come unless found and dragged out. http://en.wikipedia.org/wiki/Ghost_net
In contrast to the northern gannets common murres do not use any nesting material. They lay their single egg on the bare ledge. Since the eggs are cone-shaped they roll in a circle and are unlikely to roll off. When the youngster is ready to leave the nest the male parent calls them from the water below encouraging them to drop down the sheer cliff. They can't fly but are well-cushioned and do not get injured when hitting the water. It takes another 2 to 3 weeks or so for them to grow wings and to learn to fly and dive.