MEDICINE HAT, Alta. -- A conservation group says a federal order to protect sage grouse habitat in southern Alberta and Saskatchewan must move ahead right away if the species is to survive.

The Alberta Wilderness Association is worried about a court challenge filed by an Alberta city and an oil company seeking to have the emergency order thrown out or delayed.

The City of Medicine Hat and LGX Oil & Gas Inc. have said they are concerned about how the federal order would affect oil projects.

The order announced last month restricts oil production in areas near the sage grouse's habitat and is to take effect Feb. 18.

About 1,700 square kilometres of Crown land in the two provinces will be covered by the new rules.

Cliff Wallis of the wilderness association says the federal government must do what it can quickly to protect the sage grouse, thought to be down to as few as 90 birds.

"This is the slowest emergency I have ever seen," Wallis said Monday in a release.

"While we understand the frustration over some provisions of the emergency order and the lack of clarity in its implementation, now is not the time to postpone that implementation."

The emergency protection order grew out of a 2012 court case brought by several environmental groups to force the federal government to live up to its Species At Risk legislation.

It forbids the construction of new roads, tall fences or high objects and restricts loud noises during certain times of year.

Disturbing ground cover, such as the sage grass the grouse depend on, will not be permitted.

The rules allow for exemptions "in certain circumstances or locations" and only apply to Crown land, not private property or grazing leases. Pre-existing buildings -- residential and agricultural -- are also exempt, as is the immediate area around those buildings.

Environment Canada estimates the plan will cost about $10 million in forgone oil revenues over 10 years.

The document says impact on farming and ranching will be minimal.

The plan makes no extra commitment to restoration or research.