Seed caching and cache pilferage by three rodent species in a temperate forest in the Xiaoxinganling Mountains

Abstract

Although differences in food-hoarding tactics both reflect a behavioral response to cache pilferage among rodent species and may help explain their coexistence, differentiation in cache pilfering abilities among sympatric rodents with different hoarding strategies is seldom addressed. We carried out semi-natural enclosure experiments to investigate seed hoarding tactics among three sympatric rodent species (Tamias sibiricus, Apodemus peninsulae and Clethrionomys rufocanus) and the relationship of their pilfering abilities at the inter-and intraspecific levels. Our results showed that T. sibiricus exhibited a relatively stronger pilfering ability than A. peninsulae and C. rufocanus, as indicated by its higher recovery rate of artificial caches. Meanwhile A. peninsulae showed a medium pilfering ability and C. rufocanus displayed the lowest ability. We also noted that both cache size and cache depth significantly affected cache recovery in all three species. T. sibiricus scatter-hoarded more seeds than it larder-hoarded, A. peninsulae larder-hoarded more than scatter-hoarded, and C. rufocanus acted as a pure larder-hoarder. In T. sibiricus, individuals with lower pilfering abilities tended to scatter hoard seeds, indicating an intraspecific variation in hoarding propensity. Collectively, these results indicated that sympatric rodent species seem to deploy different food hoarding tactics that allow their coexistence in the temperate forests, suggesting a strong connection between hoarding strategy and pilfering ability.

Behavioral adaptation of sympatric rodents to early germination of oak acorns: radicle pruning and embryo excision

“…Sympatric rodents often have different foraging strategies due to competition for food resources ( Lu and Zhang, 2008 ; Zhang et al., 2014b ; Meng et al., 2022 ). Our findings presented further evidence for these observations ( Zhang et al., 2013a ; Zhang et al., 2014a ; Gu et al., 2021 ). In our study, C. canus is the largest solitary animal among nocturnal rodents with strong territorial behavior and a strong ability to defend the nest (Zhang’s personal observations), so larder-hoarding has been its efficient food-hoarding strategy ( Zhang et al., 2022 ).…”

“…All trapping was conducted at the end of the breeding season, and none of the rodents appeared to be in breeding condition. Healthy and mature rodents were transported to the laboratory and individually housed in steel frame cages (H × W × L: 40 cm × 50 cm × 90 cm) under natural temperature (15°C–25°C) and photoperiod (14 h of light) ( Zhang et al., 2013a ). All animals received carrots, peanuts, tree seeds, and water ad libitum .…”

“…Healthy acorns of Q. variabilis of uniform size (4.6 ± 0.06 g, dominant tree species in Tianchi Mountain) were selectively collected from more than 20 trees using seed traps. Acorns were labeled with plastic tags according to the previously published method ( Zhang et al., 2013a ). Each acorn was drilled with a 0.3-mm-diameter hole at the base and then attached with a writable plastic tag (2.5 cm × 3.5 cm, <0.3 g) using a thin 10-cm steel thread.…”