Rescuers extracted an injured bicyclist from the Buck Gully nature reserve Monday morning.
The mountain biker crashed while riding in the Newport Coast reserve at about 7:30 a.m. and was hoisted out by helicopter and flown to a local hospital with traumatic injuries, authorities said.
Further details about the incident were unavailable.
Fourteen members of the Newport Beach Fire Department and Orange County Fire Authority responded to the call.
Buck Gully consists of 300 acres owned by the city of Newport Beach south of San Joaquin Hills Road. It has miles of trails through protected open space and habitats for many species of plants and animals.