Effects of seed traits on the cache size of a scatter-hoarding rodent, Leopoldamys edwardsi

Abstract

Abstract Seed traits can influence post-dispersal seed fate and seedling establishment by manipulating the size of caches made by hoarding animals. However, few studies have explored how seed traits affect cache size and subsequent seed fate mediated by hoarding rodents. In this study, we investigated the effects of seed traits on hoarding behavior of Leopoldamys edwardsiusing seeds of Quercus variabilis, Castanea henryi, Camellia oleifera, Lithocarpus harlandii, and Choerospondias axillarisunder enclosures in Dujiangyan City, southwest China, in an attempt to elucidate the relationship between seed traits and cache size. Our results showed that there were significant differences in the scatter-hoarded preference among C. axillaris, C. henryi, C. oleifera, Q. variabilis and L. harlandii by L. edwardsi. There was a significant difference in the cache size between five seed species by L. edwardsi. More importantly, we found that there was a significant positive correlation between cache size and the proportion of intact after removal or crude fat, but a significant negativecorrelation between cache size and seed mass or crude starch. Our study has revealed that seed traits are a key factor in regulating the hoarding behavior of rodents, which includes the size of their caches. This behavior, in turn, has a significant impact on the fate of the seeds and the growth of seedlings that emerge from the caches. Significance statement At present, a large number of studies focus on a certain trait of a single seed or the effect of a certain seed trait of various seeds on the hoarding behavior of rodents, but how seed traits affect cache size and subsequent seed fate mediated by hoarding rodents remains unknown. This study systematically illustrates how rodents build storage sites and determine the seed fates according to seed traits. Establishing food storage sites based on different seed traits involves a trade-off between the recovery rate and the pilfering rate of food-hoarding sites, which may be an adaptive storage strategy formed in the long-term evolution process.