Marsh and shoreline erosion Erosion of coastal marshes and shorelines is a major threat in several key crane habitats. In these areas, the dredging of channels and the subsequent wave action of boat and barge traffic gradually erodes shoreline soils and vegetation. Pollution and environmental contamination Crane habitats around the world are threatened by many forms of household, agricultural, and industrial pollution. Pollution also poses an acute threat to cranes through the potential for catastrophic spills and other accidents. The presence of chemical transportation and production facilities along coastlines and major rivers makes wetlands in these areas especially vulnerable to such accidents.
Many important crane habitats around the world contain known or suspected oil reserves.
Oil development activities take place within the Aransas National Wildlife Refuge, but are prohibited when the Whooping Cranes are present. An accident at other times of the year could have long-term impacts on environmental quality throughout the refuge. Oil has been discovered in and near the breeding grounds of Siberian Cranes in eastern Russia. Collision with utility lines Accidental collision with utility lines has become a significant source of mortality in several species of cranes.