U.S. operators raised six oil rigs and one natural gas rig over the past week, with the Williston Basin drawing the most action at three new rigs in North Dakota, Baker Hughes Inc. said Friday.

Alaska, Colorado and New Mexico each added two rigs week/week, while Oklahoma, where operators are working myriad stacked reservoirs, lost four for the week. Wyoming dropped one rig.

According to Baker Hughes, there were 186 U.S. natural gas rigs and 747 oil rigs running for the week ending Friday, sharply higher from a year ago when 86 gas rigs and 337 oil rigs were in operation across the United States.

Canada for the week added 10 gas rigs to bring the total to 68, while it raised 17 oil rigs for a total of 91. The gains also were sharply ahead of a year ago, when Canada was running 40 gas rigs and 28 oil rigs.

Although Texas added no rigs for the week, the total rig count still far and away exceeds any other state basin with 460 total rigs. The state rigs were concentrated in the Permian Basin with a whopping 368, followed by the Eagle Ford Shale with 84.

Oklahoma’s Cana Woodford formation registered 59 rigs working at the end of the week, down one week/week, while the count was three higher at 49 in the Williston.

As the Dakota Access Pipeline ramps up to carry Bakken Shale crude from the Williston, anemic oil prices should retreat, according to Justin Kringstad, director of the North Dakota Pipeline Authority. It may take “at least six months” to determine if the pipe helps raise crude oil prices from the Williston, he said.

Meanwhile, the resurgent Haynesville Shale, which straddles East Texas and North Louisiana, lost one rig for the week to rest at 40 rigs as of Friday, but it was trailing the Marcellus Shale by only five and was sharply ahead of the Utica Shale’s 28 rigs. A year ago, the Haynesville had 17 rigs in operation, while the Marcellus had 24 and Utica had 12.

As of Friday, Barnett Shale was down one rig week/week to end at seven, while the Mississippian Lime also lost one to end at eight.

Horizontal rigs continue to be the leaders at 782 for the week, a gain of two from the previous seven days, but there were three directional rigs added to bring the total to 69, and one vertical rig added to end at 82.