Cpl. Tevfik Ozkaynak (left), a rifleman with Company C, 1st Battalion, 25th Marine Regiment, 4th Marine Division and Sgt. Lee Gugino (right), a squad leader, observe objective points on a map while on a reconnaissance patrol during exercise Riley Xanten II, in Burwash, Ontario, Feb. 3-5, 2017. During the exercise, the Marines joined soldiers from the Canadian Armed Forces to exchange knowledge and increase proficiency in cold weather tactics, survival skills, shelter building, ice fishing, and more. (U.S. Marine Corps photo by Sgt. Sara Graham/released) - Cpl. Tevfik Ozkaynak (left), a rifleman with Company C, 1st Battalion, 25th Marine Regiment, 4th Marine Division and Sgt. Lee Gugino (right), a squad leader, observe objective points on a map while on a reconnaissance patrol during exercise Riley Xanten II, in Burwash, Ontario, Feb. 3-5, 2017. During the exercise, the Marines joined soldiers from the Canadian Armed Forces to exchange knowledge and increase proficiency in cold weather tactics, survival skills, shelter building, ice fishing, and more. (U.S. Marine Corps photo by Sgt. Sara Graham/released)

EVANGOLA STATE PARK, N.Y. – Lance Cpl. Edward Doyle, a rifleman with Charlie Co., 1st Battalion, 25th Marine Regiment, 4th Marine Division, Marine Forces Reserve, patrols through the woods during exercise Lake Effect at Evangola State Park, New York, Sept. 12, 2015. Each platoon in Charlie. Co. set up their own patrol bases and routes which occasionally lead to confrontation with the other platoons, adding an element of realism to the training. (U.S. Marine Corps Photo By Cpl. J. Gage Karwick/Released) - EVANGOLA STATE PARK, N.Y. – Lance Cpl. Edward Doyle, a rifleman with Charlie Co., 1st Battalion, 25th Marine Regiment, 4th Marine Division, Marine Forces Reserve, patrols through the woods during exercise Lake Effect at Evangola State Park, New York, Sept. 12, 2015. Each platoon in Charlie. Co. set up their own patrol bases and routes which occasionally lead to confrontation with the other platoons, adding an element of realism to the training. (U.S. Marine Corps Photo By Cpl. J. Gage Karwick/Released)