Common types of coastal problems are: pollution, erosion, salt intrusion, flooding calamities, habitat degradation / loss of biodiversity.

As the scope and significance of biodiversity loss become better understood, positive steps to stem the tide of the sixth extinction have been proposed and, to some extent, adopted. Several nations have enacted laws protecting endangered wildlife. An international treaty known as the Convention on the International Trade of Endangered Species (CITES) went into effect in 1975 to outlaw the trade of endangered animals and animal parts. In the United States, the Endangered Species Act (ESA) was enacted in 1973 to protect endangered or threatened species and their habitats. The Convention on Biological Diversity, held in Rio de Janeiro, Brazil, in 1992 and ratified by more than 160 countries, obligates governments to take action to protect plant and animal species.

In the last three decades, focus has shifted away from the preservation of individual species to the protection of large tracts of habitats linked by corridors that enable animals to move between the habitats. Thus the movement to save, for example, the spotted owl of the Pacific Northwest, has become an effort to protect vast tracts of old-growth timber.

Promising as these approaches may be, conservation efforts will never succeed in the long run if the local economic needs of people living in and near threatened ecosystems are not taken into account. This is particularly true in developing countries, where much of the world's remaining undisturbed land is located. At the end of the 20th century, international organizations such as the World Bank and the World Wildlife Fund launched a movement for all countries in the developing world to set aside 10 percent of their forests in protected areas. But many communities living near these protected areas have relied on the rain forest for food and firewood for thousands of years. Left with few economic alternatives, these communities may be left without enough food to eat.

To address this problem, the burgeoning field of conservation biology emphasizes interaction with the people directly impacted by conservation measures. Conservation biologists encourage such people to develop sustainable economic alternatives to destructive harvesting and land use. One alternative is harvesting and selling renewable rain forest products, such as vegetable ivory seeds from palms, known as tagua nuts, and Brazil nuts. Where protection measures permit, rain forest communities may undertake sustainable rain forest logging operations, in which carefully selected trees are extracted in a way that has minimal impact on the forest ecosystem. Still other communities are exploring medicinal plants for drug development as ways to strengthen and diversify their economies.

Conservation biologists also work with established industries to develop practices that ensure the health and the sustainability of the resources on which they depend. For example, conservation biologists work with fishers to determine how many fish the fishers can harvest without damaging the population and the ecosystem as a whole. The same principles are applied to the harvesting of trees, plants, animals, and other natural resources.

Preserving biodiversity also takes place at the molecular level in the conservation of genetic diversity. All around the world efforts are being made to collect and preserve endangered organisms' DNA, the molecule that contains their genes. These collections, or gene banks, may consist of frozen samples of blood or tissue, or in some cases, they may consist of live organisms. Biologists use gene banks to broaden the gene pool of a species, increasing the likelihood that it will adapt to meet the environmental challenges that confront it. Many zoos, aquariums, and botanical gardens work together to carefully maintain the genetic diversity in captive populations of endangered animals and plants, such as the giant panda, the orang-utan, or the rosy periwinkle. Captive animals are bred with wild populations, or occasionally released in hopes that they will breed freely with members of the wild population, thus increasing its genetic diversity. These gene banks are also an essential resource to replenish the genetic diversity of crops, enabling plant breeders and bioengineers to strengthen their stocks against disease and changing climate conditions.