The use of alternative foods to reduce conifer seed predation by the deer mouse (Peromyscus maniculatus).
The upper limit to the number of mice was estimated at 36 mice/ha when 860 000 Douglas fir seeds/ha were taken. Additional seeds did not result in further increases in mouse numbers. Using this seed density, alternative foods of 7 sunflower seeds, or 5 sunflower and 2 oats, to 1 Douglas fir were provided. After 4 weeks, Douglas fir seed survival was approx. 50% vs. 5% without alternative food. The alternative foods were most successful in March-April and Nov.-Dec. Lower densities of sunflower seeds were not effective.