Rodents are well known as both seed predators and dispersers of various plant species in forest ecosystems, and they play an important role in the regeneration of vegetation. Thus, the research on seed selection and vegetation regeneration by sympatric rodents is an interesting topic. To understand the characteristics of preferences of rodents for different seeds, a semi-natural enclosure experiment was performed with four rodent species (Apodemus peninsulae, Apodemus agrarius, Tscherskia triton, and Clethrionomys rufocanus) and the seeds of seven plant species (Pinus koraiensis, Corylus mandshurica, Quercus mongolica, Juglans mandshurica, Armeniaca sibirica, Prunus salicina, and Cerasus tomentosa) to investigate the differentiation in niches and patterns of resource utilization of sympatric rodents. The results showed that all the rodents had consumed many seeds of Pi. koraiensis, Co. mandshurica, and Q. mongolica but differed significantly in how they selected the different seeds. The rate of utilization (Ri) of Pi. koraiensis, Co. mandshurica, and Q. mongolica exhibited the highest values. The Ei values indicated that the rodents tested exhibited differences in their priorities used to select the seeds from different plant species. All four species of rodents exhibited obvious preferences for certain seeds. Korean field mice preferentially consumed the seeds of Q. mongolica, Co. mandshurica, and Pi. koraiensis. Striped field mice favor the seeds of Co. mandshurica, Q. mongolica, P. koraiensis, and Nanking cherry. Greater long-tailed hamsters prefer to consume the seeds of Pi. koraiensis, Co. mandshurica, Q. mongolica, Pr. salicina, and Ce. tomentosa. Clethrionomys rufocanus likes to eat the seeds of Pi. koraiensis, Q. mongolica, Co. mandshurica, and Ce. tomentosa. The results supported our hypothesis that sympatric rodents overlap in food selection. However, each rodent species has a marked preference for food selection, and different rodent species differ in their food preferences. This reflects the role of distinct food niche differentiation in their coexistence.
