The bulk of the fire is threatening the Carrizo Plain National Monument, which is home to several endangered and threatened wildlife and plant species.

River 2 Fire initially started today at 4:46 a.m. in San Luis Obispo County, California. After being active for less than an hour, it has burned 0.5 acres of private land. There is no update on the containment of the fire and its cause remains unknown.

The Madre Fire in eastern San Luis Obispo County continued to grown overnight as firefighters battle challenging conditions at the large blaze. According to Cal Fire's Saturday incident report at 7 a.