San Bernardino County turned over about a dozen roads in the Mojave Preserve to the National Parks Service this week. The county had sued in 2006 over its rights to the roads because county crews had been maintaining them for decades before the preserve was created as part of the 1994 Desert Protection Act. In the settlement last year, the county agreed to give up its claims to the roads. In turn, the federal government agreed to maintain them and keep them open. The Board of Supervisors formally approved the agreement Tuesday. Environmental groups had backed the settlement, saying it would keep the roads open while also protecting desert tortoises, bighorn sheep and other sensitive species along the routes in the eastern Mojave Desert. County officials were concerned about the federal agency maintaining the roads, some of which cross private lands, and on which many residents rely.