Smithsonian Tropical Research Institute (STRI), Balboa, Panama.
Ecol Lett. 2012 Dec;15(12):1423-9. doi: 10.1111/ele.12000. Epub 2012 Sep 7.
Scatter-hoarding animals spread out cached seeds to reduce density-dependent theft of their food reserves. This behaviour could lead to directed dispersal into areas with lower densities of conspecific trees, where seed and seedling survival are higher, and could profoundly affect the spatial structure of plant communities. We tested this hypothesis with Central American agoutis and Astrocaryum standleyanum palm seeds on Barro Colorado Island, Panama. We radio-tracked seeds as they were cached and re-cached by agoutis, calculated the density of adult Astrocaryum trees surrounding each cache, and tested whether the observed number of trees around seed caches declined more than expected under random dispersal. Seedling establishment success was negatively dependent on seed density, and agoutis carried seeds towards locations with lower conspecific tree densities, thus facilitating the escape of seeds from natural enemies. This behaviour may be a widespread mechanism leading to highly effective seed dispersal by scatter-hoarding animals.
分散贮藏动物将贮藏的种子分散开来，以减少对其食物储备的密度依赖性盗窃。这种行为可能导致向同种树木密度较低的区域有针对性地扩散，在这些区域，种子和幼苗的存活率更高，并且可能深刻影响植物群落的空间结构。我们在巴拿马的巴罗科罗拉多岛用中美洲豚鼠和星油藤种子对这一假说进行了测试。我们对豚鼠贮藏和重新贮藏的种子进行了无线电跟踪，计算了每个贮藏点周围成年星油藤树的密度，并检验了种子贮藏点周围观察到的树木数量是否比随机扩散时预期的要少。幼苗建立成功率与种子密度呈负相关，豚鼠将种子带到同种树木密度较低的地方，从而帮助种子逃避天敌。这种行为可能是一种广泛存在的机制，通过分散贮藏动物实现了高效的种子扩散。
