"We are increasingly a coastal species. Some 44% of the world's population lives within 150 km of the coast more people than inhabited the entire planet in 1950. Mass migration to the coasts will continue in the decades ahead. This population growth is concentrated in large coastal cities.
Coastal population growth and the activities that accompany it not only increase pollution, they radically alter coastlines. Clearing, land reclamation, and channelisation of flood and tidal waters destroy coastal wetlands. Port development, road building, coastal construction, and the mining of beach sand for construction material obliterate shoreline habitats. These activities often increase coastal erosion and damage habitats, such as seagrass beds and coral reefs, away from the development site. In some countries, mining of coral reefs has destroyed them. Exotic species introduced with ships’ ballast water and by other means threaten human health, marine ecosystems, and fisheries."