Grassland birds are declining across North America, and they are having a particularly tough time in North Dakota with the substantial increase in oil/natural gas development in the Bakken shale, according to a study released Wednesday by the U.S. Department of Interior (DOI).

Completed by DOI’s U.S. Geological Survey (USGS) and the U.S. Fish and Wildlife Service (FWS), the study concluded that “detrimental effects” from oil extraction on bird habitat “extend considerably beyond the immediate oil wellsites.”

The study’s lead USGS scientist and author, Sarah Thompson, concluded that many bird species in the region, including those with “serious declining populations,” have been displaced from their habitats as a result of oil/gas activity.

The problem could be mitigated through the alteration of various activities and their locations, according to researchers. Shutting down oil/gas development was not specifically recommended in the “Birds in the Bakken: Oil Development Can Affect Critical Habitat.”

A spokesperson for the North Dakota Petroleum Council (NDPC) told NGI‘s Shale Daily that most operators in North Dakota are well ahead of the study, “taking the extra steps to minimize footprints that the study called for, including confining development to energy corridors.

“We are also ahead of this study in our efforts to work with the ND Game and Fish to minimize impacts using GIS overlay maps for other species and adhering to best recommended practices,” said NDPC’s Tessa Sandstrom. “We believe it is important for the U.S. Fish and Wildlife Service to have current, peer-reviewed scientific studies when considering listing species, and we are glad they will have the new report. The industry has been and will continue to be involved in many conservation efforts for species mitigation.”

Quantifying environmental degradation caused by oil development is a critical step in understanding how to better mitigate harm to valuable wildlife populations, said Thompson, who thinks the study will help oil/gas operators determine the best locations for infrastructure development.

While the findings point to reducing road construction and concentrating multiple wells on single pads, the study had some specific findings:

● Individual species have varying tolerances for oil wells;

● Declining populations of three species (Baird’s sparrow, chestnut-colored longspur and grasshopper sparrows) were observed by the researchers as far as 550 meters from a well bore;

● Found to be tolerant of oil-related infrastructure are the clay-colored sparrows and brown-headed cowbirds; and

● The sprague’s pipit, a candidate for the federal Endangered Species Act listing, showed reduced population density within 350 meters of a well bore.

Thompson said that the findings point to cutting the loss of suitable bird habitat through “reducing new road construction, concentrating wells along developed corridors, and combining numerous wells on multi-bore pads, along with placing wells near existing roads.”

The study said the Bakken oil-producing region of western North Dakota, eastern Montana and Midcontinent Canada provide the home for a “high density and diversity” of grassland bird species that are in decline.

From 2012 through last year, USGS and FWS scientists studied the Bakken grassland sites in northern North Dakota that include well pads with gravel surfaces. They found that overall, the birds avoid the areas within 150 meters of the wellsites, or about 492 feet of gravel roads.

“These results suggest that detrimental effects of oil extraction on habitat extend considerably beyond the immediate oil well sites,” the study said.