Vandegrift and his staff were aware that Kawaguchi's troops had retreated to the area west of the Matanikau and that numerous groups of Japanese stragglers were scattered throughout the area between the Lunga Perimeter and the Matanikau River. Vandegrift, therefore, decided to conduct another series of small unit operations around the Matanikau Valley. The purpose of these operations was to mop up the scattered groups of Japanese troops east of the Matanikau and to keep the main body of Japanese soldiers off-balance to prevent them from consolidating their positions so close to the main Marine defenses at Lunga Point.