Sedgwick Reserve

30 Jun, 05 PM - 29 Jun, 05 PM

Fragmentation and population declines jeopardize the survival of many species. Excessive reproductive isolation can cause a loss of valuable alleles, decrease genetic variation, induce inbreeding depression, reduce demographic fitness, and lead to reproductive failure. When tree populations are reduced to scattered and clustered individuals, pollen movement is critical to connectivity. This project develops a novel approach that is can cover landscape-scale areas and can be integrated into spatially explicit simulation modeling of landscape changes. These new tools are deployed to investigate a threatened tree species, California Valley oak (Quercus lobata). Using allozyme and microsatellite genotypes, w examine three objectives: (1) We will characterize reproductive isolation of individual trees in landscapes with variable conspecific density. (2) We will examine the impact of adult genetic structure and temporal heterogeneity of pollen pools on estimates of pollen movement. (3) We will incorporate estimated parameters into geographic models to simulate the impact of historical and future population decline. During AY 2002-2003 we will continue to sample acorns and leaf tissues from valley oaks in lower Figueroa and Lisque Canyons. Depending on fruit availability, 10-20 acorns will be harvested from 150-200 mapped, tagged trees. Selected branches will be enclosed in nylon mesh bags prior to fruit drop. Acorn production per tree will be roughly estimated using 30-second visual counts. Genetic analyses will be performed at UCLA. GIS analyses will be performed at UCSB, and statistical analyses will be conducted at Rutgers.

Visit #1541 @Sedgwick Reserve

Approved

Under Project # 1269 | Research

Landscape patterns of pollen movement in declining populations of California Valley Oak, Quercus lobata

faculty - University of California, Santa Barbara

Reservation Members(s)

Group of 2 Graduate Student Jun 30, 2002 - Jun 29, 2003 (365 days)
Group of 3 Faculty Jun 30, 2002 - Jun 29, 2003 (365 days)
Frank Davis Jun 30, 2002 - Jun 29, 2003 (365 days)

Reserve Resources(s) | Create Invoice