Date of Completion


Degree Type

Honors Thesis


Biology (BIOL)

First Advisor

Victor G. Carmona, Ph.D


The California Horn Snail (Cerithideopsis californica) is an important primary intermediate host in the life cycle of a variety of parasitic species that have extensive effects on ecological food webs. As such, parasite load in the California Horn Snail can serve as an important tool in assessing the effectiveness of restoration projects. The goal of the study was to investigate the population dynamics of the California Horn Snail in Ballona Wetlands, California, the only major coastal salt marsh in Los Angeles County. This study evaluated the spatial dispersion, size distribution, and density of C. californica collected from the Ballona Wetlands Ecological Preserve. The results showed that the population of C. californica in the preserve exhibited a bimodal distribution of size, with the large and small cohorts exhibiting significantly different patterns of dispersion. The study suggests that both bimodal size distribution and size-associated behavior of C. californica may be important for understanding this ecologically important snail.