Newly discovered damage to part of the dam holding back America's second-largest reservoir has people who rely on the Colorado River worried about their ability to get the water they need.
People who fish in Florida and in federal waters are required to have special gear on board to help ensure groupers, snappers and other reef fish survive when they're returned to the water.
Climate change is heating oceans faster than the world's coral reefs can handle. So scientists are breeding corals that can withstand hotter temperatures – but only to a point.
The National Park Service is seeking the public's help in identifying the two men, caught on video pushing rocks off a cliff near the Redstone Dunes Trail earlier this month.
We visit an orchard where researchers are breeding Chestnut trees they hope will one day fight off a fungus that's been killing the iconic American tree for more than a century.
Akagera National Park in eastern Rwanda was hard hit by the violence of the country's genocide. For a time, the park floundered — but it's now flourishing.
Japan is giving the U.S. 250 new cherry trees to help replace the hundreds that are being ripped out this summer as construction crews work to repair the seawall around the capital's Tidal Basin.