Animal space use alters the impact of food availability on cache spacing for Eurasian red squirrel
(0) Scatter hoarders are not able to defend their caches.A greater hoarding distance combined with greater cache spacing can reduce cache losses but increases the costs of hoarding and retrieving.Scatter hoarders arrange their caches to achieve an optimal balance between costs and main cache losses.We conducted systematic cache sampling investigations to estimate the effects of food availability on cache spacing for the Eurasian red squirrel (Sciurus vulgaris) in two patches of a Korean pine (Pinus koraiensis)-dominated forest with contrasting seed productions patterns over a period of five years.Drey trees locations were determined to obtain data on animal space use as part of the investigations.The squirrels selectively hoard heavier pine seeds farther away from seed-bearing trees.The heaviest seeds were placed in caches around drey trees,regardless of their location,and this placement was not a response to decreased food availability.The cache density declined with the hoarding distance.At sites with lower seed production and during off years,the squirrels’ cache density was lower.In extreme mast years,the cache density in samples around drey trees was higher and stable.The pine seeds were dispersed over a greater distance when seed availability was lower.Our results suggest that 1) animal space use behavior is an important factor that affects the food hoarding distance and associated cache spacing; 2) animals employ different hoarding strategies in situations with contrasting scales of food availability; and 3) seed dispersal outside of the original stand is stimulated in off years.
scatter hoarding cache spacing Sciurus vulgairs Pinus koraiensis
Ke Rong Cheng Zong Hui Yang Meisuonancuo Jiangzhang Ma
College of wildlife resource,Northeast Forestry University,Harbin 150040,China
国内会议
南京
英文
1-14
2012-09-01（万方平台首次上网日期，不代表论文的发表时间）