FARGO (AP) - Officials are studying mule deer and birds in western North Dakota to help determine the impact of oil activity on wildlife.
There are about 7,000 wells in the oil patch, and officials predict that number could rise to 35,000 in the new few decades, The Forum newspaper reported.
"There will be substantial reduction in our wildlife populations," said Aaron Robinson, a wildlife biologist with the North Dakota Game and Fish Department. "I don't think there's anyone who can argue that."
Habitat destruction or disruptions displace both animals and birds, Robinson said.
"It just pushes these animals into areas that are not as optimal," he said. "It's just kind of a domino effect."
Researchers in one study have equipped 90 female mule deer with radio collars to track survival rates. Mule deer browse on a lot of plants and are considered a species that will provide an early indicator of the impacts of oil development on wildlife, said Jesse Kolar, a University of Missouri graduate student who is doing field work.
Biologists will study mule deer populations primarily in Badlands terrain from the Amidon area in the south to the Watford City and Tobacco Gardens areas near Lake Sakakawea to the north. Researchers will monitor survival rates, noting whether does and fawns survive from spring into summer and through the winter, Kolar said.
Officials also are studying sage grouse, which require sagebrush habitat, to distinguish impacts on populations from oil and gas development and other influences, including weather patterns.
"There definitely is an effect," Robinson said of oil and gas development. "We're trying to quantify the amount. It's a challenge."
Preliminary results of another study headed by the U.S. Geological Survey found that several grassland bird species - most notably grasshopper sparrows - are avoiding oil drilling sites.
"There was a lot of concern about what was happening," said Doug Johnson, a Geological Survey researcher. "We're aware that there's an incredible amount of human activity out there."
He said long-term effects still are not known.
The North Dakota Legislature is weighing proposals to create an outdoors heritage fund.
Gov. Jack Dalrymple has proposed an outdoors protection fund of $15 million annually to aid conservation. It has passed the House and a Senate committee.
Conservation advocates had been promoting a fund that would generate more than $100 million a year, a funding level that has not won significant legislative support.
A recent North Dakota State University study concluded that hunting and fishing - which depend on healthy wildlife populations - contribute $1.4 billion a year to the state's economy.
"Even $100 million a year is a relatively small amount for a $1.4 billion-a-year tourism and outdoor recreation industry," said wildlife advocate Mike McEnroe.