SALT LAKE CITY -- A once-lively rest stop for migrating birds on the shore of the Great Salt Lake has grown parched over the last 40 years, the likely victim of water siphoned away for farming and the ongoing drought, according to a new study.

State researchers say flow from a set of natural springs near the north end of the lake has dropped 80 percent since the late 1960s.

The result has been fewer places to stop, rest and eat for thousands of migrating birds that pass through the area each year.

"It's been pretty significant accumulative losses over time," said Randy Berger, manager of the Locomotive Springs Waterfowl Management Area, a remote refuge at the northern edge of the lake's west arm.

Two large bodies of water and hundreds of acres of squishy wetlands have dried up. Another water impoundment survives. And instead of thousands of visiting birds, the area -- a freshwater oasis amid the cracked and dry desert -- now supports fewer than 1,000 ducks, a few hundred geese and "very few" shorebirds, Berger said.

"They just don't stop there anymore," said Berger, who has worked at the waterfowl area since 1988.

The decline corresponds with a significant increase in groundwater pumping for agriculture upstream from the wildlife area and below-average precipitation, according to a study by the Utah Geological Survey and the Utah Division of Water Rights.

The study focused on the Curlew Valley, a 1,200-square mile basin that stretches across northwest Utah and part of south-central Idaho.

Agricultural operations are a mainstay of the economy in the area. Water melting from the mountains supplies wells, and provides water for crops and to raise animals. It has also traditionally fed six springs at Locomotive Springs.

In the late 1960s, those springs averaged about 40 cubic feet of water per second, the study said. It's now less than 10 cubic feet per second. Not much of a roar for place called Locomotive Springs.

Hugh Hurlow, with the Utah Geological Survey, said the study began looking at data starting in 1968 "but the decline was already in progress by then."

In the aftermath of the Great Salt Lake floods in the 1980s, the lack of water flowing from Locomotive Springs made it more difficult for wetlands to fully recover. Bird habitat and the amount of wetlands in the area has been "drastically reduced," according to the study.

Researchers also noted that the quality of the water in the area had also worsened.

Matt Lindon, the assistant state engineer, said the study is the first time long-discussed water flow problems in the area have been quantified. He's hoping the report will spark discussions among water users, politicians, state officials and others about whether changes need to be made.

"It's kind of a balancing act, trying to take care of those agricultural interests and still having enough water for the springs," Lindon said. "What we're looking for is some sustainability."