Collaborative research: Seed-flow in California Valley Oak (Quercus lobata)--Novel Approaches to an Old Problem

University Of California-Los Angeles, Los Angeles CA

Investigators

Abstract

Human-caused disturbances, such as landscape fragmentation and alteration, loss of dispersal agents, and global warming, require that plant populations be able to disperse both genes and individuals to new sites. We introduce an innovative approach to the study of seed flow, based on molecular genetic analysis of maternal tissue in the seed coat, by analyzing the seed pool structure of sets of seeds dispersed across a landscape. We will apply this novel analysis to seed dispersal of a threatened tree species, California valley oak, by the acorn woodpecker. We have two objectives: (1) to conduct novel theoretical work on the statistical model that allows hypothesis testing on seed dispersal under different circumstances; (2) to examine the seed pool structure and dispersal distances of seeds found in acorn woodpecker storage sites, and recruits in natural seedling patches. This research makes several valuable contributions. (1) It develops methods for studying seed dispersal that are applicable to a wide range of species, including those experiencing landscape change and loss of vertebrate dispersers. (2) It contributes to a growing discussion by ecologists and population genetics about the shape of the seed dispersal distribution. (3) Results from this study will be included in several K-12 environmental workshops, meetings with policy-makers, nd state and federal scientists.