"Green groups urged the U.S. Department of Interior on Tuesday to revoke the agency's conditional approval of Royal Dutch Shell's 2015 Arctic oil exploration plan, saying it runs counter to established protections for walruses.

A 2013 rule implemented by the Fish and Wildlife Service, a bureau of the Interior Department, prevents energy companies from exploring for oil simultaneously at wells in the Chukchi Sea off Alaska that are within 15 miles (24 km) of each other.

The rule is meant to protect walrus populations that are sensitive to the noise and disruption of drilling in their habitat."

Timothy Gardner reports for Reuters June 23, 2015. [2]