An unidentified substance has killed or injured hundreds of birds so far.
Startling maps in a new report on the Sacramento-San Joaquin Delta show the dramatic loss of marshlands that once supported a vast array of wildlife.
For more than two decades, environmental groups and numerous agencies have worked to restore the wetlands at the former Hamilton Army Airfield. On Friday, the project achieved a significant milestone.
A team of federal scientists is surveying areas burned by the Rim Fire to identify where the worst erosion danger is. An environmental group says restoration could cost tens of millions of dollars.