Why more birds use human-made materials in their nests

Many birds are urban-adapted and breed successfully in cityscapes where human-made materials are readily available. But with the accumulation of plastic on beaches, there is evidence that birds on nearly all continents are using these materials for nest-building

A Northern Gannet sits on a nest made of plastic nets on the Lummenfelsen cliff on the island of Heligoland, northern Germany, last year. Findings imply that human-made materials are being included in nests intentionally—the birds are showing off. File photo: Focke Strangmann

Interactions between wildlife and plastic litter have been well documented in the sea. Think of seals entangled in netting or whales permanently attached to discarded fishing tackle, so-called “ghost gear”.

But it is birds that may encounter discarded human-made material the most of all animal groups, as they are extremely mobile and can be found almost everywhere in the world. There are many reports of seabird chicks dying after being entangled in old plastic and fishing nets, for instance.