More than three dozen endangered Rio Grande silvery minnows were found dead and more than 4,200 of the tiny fish were rescued this week as a stretch of the Rio Grande went dry.
"We lost the river early Monday morning," said Connie Rupp, area manager for the U.S. Bureau of Reclamation.
Rules designed to protect the tiny fish require the bureau to keep the river flowing through June 15, but recent hot, dry and windy weather was more than water managers expected.
At the southern end of the Bosque del Apache National Wildlife Refuge, nearly 5 miles of the Rio Grande was dry Tuesday afternoon.
The Bureau of Reclamation released extra water from upstream reservoirs and stepped up pumping of water into the river from a nearby channel. The refuge also stopped diverting water and the Middle Rio Grande Conservancy District altered its operations to help get more water downstream quickly.
By Wednesday, much of the area was flowing again.
The U.S. Fish and Wildlife Service is assessing the impacts of the drying and what should be done in its wake, said Larry Bell, the agency's assistant regional director.
Ed Polasko, a National Weather Service hydrologist, said it's early for the river to be drying up.
"I mean, it's not even June," he said.
Most of the state is in moderate drought and at least a quarter is in severe drought, Polasko said.
There is some hope. Forecasters said the monsoon season should be average to better-than-average.
"If we don't get the monsoons, it's going to be a very difficult year," Rupp said.