March brings the return of the greater sandhill cranes to Colorado as they migrate from winter habitat in the south to summer nesting and breeding grounds in Idaho, Montana and Canada.

About 25,000 birds were expected over the weekend in the San Luis Valley in southern Colorado, where the city of Monte Vista drew about 3,000 to its 24th annual crane festival.

Some cranes are expected to feed and rest in the San Luis Valley for the next two weeks, especially at the Russell Lakes State Wildlife Area and the Monte Vista National Wildlife Refuge, said Joe Lewandowski, a spokesman for the Colorado Division of Wildlife. The sanctuaries are about 220 miles south of Denver.

"They've been migrating for thousands of years, and there's nothing to indicate their migration patterns are changing," Lewandowski said. "If anything, the birds are showing up in more parts of the state, which is an indication they are in good shape."