This winter, within Yellowstone National Park, there will be the usual sights, like bubbling geysers, buffalo roaming and quite possibly a few wolves in pursuit of a good meal.

There will also be snowmobiles and snowcoaches on the groomed trails within the park.

And under the recently released record of decision issued by the park last month, there will be snowmobiles and snowcoaches in the park in the winters to come.

The park is scheduled to open for the winter on Dec. 19.

This winter the allowable limit for on-snow travel, which was set under an appropriations bill issued by Congress in 2005, is 720 snowmobiles per day and 87 snowcoaches, with no limits on the number of cross country skiers.

Next winter, however, the final numbers allowed under the record of decision — derived at after the park's three-year study on sound and emissions — will be reduced to 540 snowmobiles and 83 snowcoaches allowed into the park each day during the winter schedule.

Also, all snowmobiles going into the park this year and in the future must fall under the best available technology classification and must go into the park with a professional guide.

The numbers, said Al Nash, spokesman for the park, fall within acceptable limits and tolerances for both sound and emissions.

"There's no question, (park staff) have done the job set down before us, which was to deal with the unacceptable impacts we had under historic conditions," said Nash.

"We have a great deal of confidence on the data we've been able to collect under conditions of limited (snowmobile) use and with the new (best available technology) machines."

Within hours of the decision, two lawsuits challenging the inclusion of snowmobiles were filed, one under a group lead by the Greater Yellowstone Coalition and the second by the National Park and Conservation Association. Those lawsuits are not expected to be addressed until after the winter season.

The groups are asking for the complete elimination of snowmobiles in the park in favor of snowcoaches.

Nash admitted, however, that there were still some areas in the environmental impact statement, which was conducted over the three years, "that still need to be addressed to better ensure our protection of resources."

This would include enforcing sound and emission standards for snowcoaches by the winter of 2010-11.

Several years ago, all snowmobiles that were being allowed into the park had to fall under best available technology classification.