Subscribe Now! National Geographic Magazine $15
Visit our Online Shops

Sign up for free

Newsletters

Once a month
get new photos
and expert tips.

Freshwater Threats

Photo: A heat-damaged reef in the Indian Ocean offers poor habitat for fish
Fish in overbleached coral

Freshwater ecosystems are essential for human survival, providing the majority of people's drinking water. The ecosystems are home to more than 40 percent of the world's fish species. Despite their value and importance, many lakes, rivers, and wetlands around the world are being severely damaged by human activities and are declining at a much faster rate than terrestrial ecosystems.

More than 20 percent of the 10,000 known freshwater fish species have become extinct or imperiled in recent decades. Watersheds, which catch precipitation and channel it to streams and lakes, are highly vulnerable to pollution. Programs to protect freshwater habitats include planning, stewardship, education, and regulation.

Threats

  • The creation of dams and water-diversion systems blocks migration routes for fish and disrupts habitats.
  • Water withdrawal for human use shrinks and degrades habitats.
  • Runoff from agricultural and urban areas hurts water quality.
  • Draining of wetlands for development depletes habitats.
  • Overexploitation and pollution threaten groundwater supplies.
  • Invasion of exotic species can harm native animals and plants.
  • Global warming may lead to devastating floods and droughts.

Solutions

  • Restrict the construction of dams.
  • Provide incentives for farming business to reduce the use of pesticides.
  • Establish protected wetlands areas.
  • Regulate water withdrawal for human use.

Related Features

Photo: Twilight view of cattails growing on the banks of a freshwater lagoon in South Carolina's Huntington Beach State Park

Photo Gallery: Fresh Water

Drink in freshwater scenes from around the world, from Yellowstone to Ethiopia, and learn about the different ecosystems that accompany them in this gallery.

Photo: Surveyor's rod on Bourbon Street

The Big Uneasy: Gone With the Water

Louisiana's wetlands are disappearing under the Gulf of Mexico at the rate of 33 football fields a day. What are the long-term consequences to the area and the industries?

Photo: Large waves characterize the Southern Ocean surrounding Antarctica

Habitats Quiz

Earth's surface is made up of thousands of different habitats and ecosystems, all with unique characteristics. Can you tell the difference between a desert and a tundra? Know how much of Earth's surface is all wet?

Earth Topics

SPECIAL ADVERTISING SECTION

Photo: Reflection on Yellowstone Lake, Yellowstone National Park

Photo Contest

Share your shots and you could win a trip to the Grand Canyon!

Photo: Puerto Escondido

Interactive Map

Visit Mexico with this interactive map.

Six Degrees Book and DVD

Image: Six Degrees DVD and book

Get an eye-opening warning of the dangers of climate change, one degree at a time.

Support Conservation

Photo: Two penguins

Help conserve the world's natural resources.

National Geographic Kids

Image: A cross-section of the human head

Play games, watch videos, and much more in this just-for-kids site.