SAN FRANCISCO (CN) - The National Park Service did not properly study how horses and mules affect California's Sequoia and Kings Canyon National Parks, a federal judge ruled.
The environmental group High Sierra Hikers Association challenged the agency's management plan for the Sequoia and Kings Canyon National Parks in a 2009 federal lawsuit, saying the plan did not make detailed findings about the environmental impacts of stock animals.
"Commercial outfitters run pack and saddle stock (i.e. horses and mules) throughout the parks, where the animals continue to trample soils, pollute the water, and provoke numerous complaints from park visitors," the complaint said.
U.S. District Judge Richard Seeborg found Tuesday that the National Parks Service violated the Wilderness Act.
The hikers' association had said that stock operators obtained permits "without first developing more stringent environmental protections" in their management plans.
Judge Seeborg was unconvinced with the Park Service's attempt to differentiate between "providing commercial services" and "authorizing continuing use of [existing] commercial services."
"The crucial inquiry is not whether the agency is increasing or maintaining - permitting or authorizing - current levels of commercial activity, but rather whether the agency has conducted a sufficient comparative and qualitative analysis," he wrote.
Based on the Wilderness Act, the Parks Service was required to determine that continuing stock use at current levels is necessary, Seeborg found.
Because the Park Service made a full environmental impact statement, the judge said it had complied with the requirements of the National Environmental Policy Act.
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