Wetland are necessary for wildlife to live, so preserving them is the right thing to do. Not only that, people are encroaching on them and they are rapidly dwindling, leaving the existing swamps and rivers polluted but the natural animal species that call them home, without a place to live. Slowly and surely if something isn't done the natural habitat for animals will steadily give way to human habitation. When this happens some animals once plentiful, will be extinct.
Even if animals do not live in wetlands they need these places to search for food and to lay eggs, and to rear their young. Wetland are their natural habitats, affording some species shade and water, both of which they cannot live without.
In hot tropical climates, animals and people and all life, depend on the cooling shade of wetlands for survival. They could not live long if these should vanish. How then can the devastation be stopped? If enough people want it stopped, it will stop. When they see for themselves what bigger and better housing and high-rises are doing to the environment, they can preserve their wetlands.
Governments and the state must step in and say when enough is enough. And this only happens when the state - and the government - has caring politicians who understand what is at stake; and who do not close their eyes to what is taking place; and who have enough courage and support to stand up and deny permits to construction that will take over wet lands. And while it is necessary and reasonable to allow humans to encroach on the fringes of these places, as parks, and other recreational areas, there must be vast areas that are left natural and untamed.
Look at what's happening in Florida. Construction in South Florida is a big booming business. One wonders where and when it's going to slow down. What's going to happen to their exotic animals and birds and beautiful unique scenery if the everglades ever goes completely dry. It is too horrible to imagine.
Again, how to preserve the wetlands? Care. Learn. Point out to others why they are necessary. Learn to live with less. Don't insist on more room to 'turn around in than you need'. Conserve. Be environmentally conscious. And whatever you do, don't buy a house in one of these new developments if the land is reclaimed from a wetland. And talk about how the wetlands are needed and insist that the people, and especially the schools in your area, understand the importance of wetlands.
But first research the facts about these dwindling areas so you will be knowledgeable about these areas. This will be necessary so that when the topic of wet lands come up, you will have the facts and figures to make a reasonable argument.