Acorn Dispersal of California Black Oak after a Stand-Replacing Fire

[摘要] We investigated California black oak (Quercus kelloggii Newberry) acorn dispersal by rodents and birds in the months after a stand-replacing fire in a mixed conifer forest in the San Bernardino Mountains of southern California, USA. The objective of this study was to compare scatter-hoarding in a high-severity burn to that in an unburned forest. In the fall of 2007, we placed 600 magnet-bearing acorns under trees in the unburned area. Of the 600, we recovered 77 (13%). Dispersers moved acorns an average distance of 5 m and buried them to an average depth of 30 mm. By spring of 2008, 90% of the cached acorns were missing. In the high-severity burn, we recovered 59 (9.8%) of the 600 acorns placed under top-killed oaks; these had been scatter-hoarded an average of 5.27 m from the source plots and buried an average of 22 mm. By spring of 2008, 55% these acorns were missing, and many of those that we relocated had been re-cached in new locations. Our results suggest that scatter-hoarding of acorns may be a common phenomenon after fire, and likely plays an important role in seedling recruitment.

[学科分类] 生态、进化、行为和系统

[关键词] acorn dispersal;California black oak;magnet-bearing acorns;Quercus kelloggii;San Bernardino Mountains;southern California;stand-replacing fire