Forest disturbance type differentially affects seasonal moose forage

摘要: We examined the effects of forest disturbance on forage availability, moose (Alces alces) seasonal selection, and predicted in vivo digestibility eastern Maine. Wet-mass estimates dry-mass conversions species consumed by 3 tamed were made throughout year (late winter, early spring, late summer, fall, winter) bud worm (Choristoneura fumiferana) defoliated, defoliated-clearcut, defoliated-clearcut-burned, undefoliated (control) 60- to 80-year-old spruce-fir (Picea-Abies) stands. Four treatment replicates sandy (deep) 2 silty (shallow) soils. Three plots also established soils within both 5- 14-year- old wildfire burns. Diet samples mixed proportions eaten field representing plant parts during 564 individual feeding bouts digested (in vitro) with cattle rumen fluid, converted using forages known digestibility. Forage dry mass consumption group selection was related treatment, season, few exceptions, availability. Dry ranged from 152 g/hr (early winter controls) 1,320 (summer 14-year-old wildfire). Digestibility diet changed growing but not dormant (November April) period. 29% spring (pre-leaf-out) wildfire) 47% (fall (80) defoliated-clearcut defoliated-clearcut-burned (combined) (post-leaf-out) 5-year-old Deciduous woody most commonly eaten, accounting for: 15 70% (depending season) controls; 25 budworm defoliated stands; 50 85% "recently disturbed" (clearcut, clearcutand burned, wildfire); 80% or greater plots. Moose ate significant amounts previously unobserved what have been considered insignificant groups (fallen hardwood leaves, ferns, Rubus spp., spruce (Picea spp.)). Natural human-caused disturbances differ their production use. Control plots, through time, produced limited least digestible , forage. following cutting controlled burns similar, than that control Although greatest amount available forage, similar observed production, up 6 growing-seasons post-treatment, reduced more wildfires other examined.