The Rio Grande, a major water source for much of the Southwest, contains just half the water it did during recent drought years.
“The population bloomed, and this year virtually all of them could die,” said Pelz, who noted that a handful of other birds and fishes will be imperiled by a dry winter.
At most survey sites in New Mexico and southern Colorado, snowpack levels were recently logged at less than 25 percent of average.
“If things remain dry, a record-low runoff year is nearly assured,” Goodbody said.
Throughout the Rocky Mountain headwaters of the Colorado River, snowpack levels are 67 percent of the 1980-to-2010 median.
“When that happens, what looks like will be a drier-than-average year can quickly become a very dry year,” she said.
The reservoirs of the Colorado River are seriously depleted, with Lake Powell just 56 percent full and Lake Mead 41 percent full.
Pitt said Lake Mead’s surface elevation has rarely been so low since the reservoir was first filling with water during World War II.
Lake Shasta, the state’s biggest reservoir, is three-fourths full.
“But forests don’t see a benefit from full reservoirs,” Lund said.