Lisa Gilbane
In 1997, I completed my B.S. from the University of Southern California. I started into a career researching human pathogens but I did not enjoy spending everyday inside, under a ventilation hood, wearing latex gloves. After moving around a bit and having discovered the field of ecology, I applied to CSU, Fullerton.
In January of 2002 I began my M.S. degree. I spend some of my time handling data in the lab and field sampling for some of Steve’s long-term monitoring projects. These projects have let me spent more time outside and brought me to two Channel Islands and many southern California mainland beaches, so far. For my thesis, I am currently investigating carbon sources for the sea mussel, Mytilus californianus, using stable isotope analysis. I am interested in community level marine ecological processes, such as the transfer of energy within a community and how energy flows change through time.
Expected Graduation Date: Spring 2004
Email: lag10@hotmail.com
Master's
Thesis:
Connection of macrophyte abundance to the diets of Mytilus californianus,
based on d13C and d15N measurements
The intertidal sea mussel, Mytilus californianus relies largely on macrophyte-derived particulate organic matter (POM) when in areas of high macrophyte abundance. This mussel also consumes other sources of production, such as phytoplankton, but it has not been clearly established which sources M. californianus utilizes in areas that lack high macrophyte abundances. This relationship between macrophyte abundances and M. californianus diets is important to understand in southern California, where mussels standing stocks and macrophyte populations have declined in abundance and are sometimes absent in Orange County. The goal of my study is to determine the variation in macrophyte derived POM to diets of southern California mussel populations of M. californianus over a habitat gradient in macrophyte abundance. I will use carbon (C13) and nitrogen (N14) stable isotopes to determine the food sources of M. californianus distributed across three sites that have exhibited persistent differences in macrophyte abundances. I predict that M. californianus will show differences in isotopic ratios among sites, in a pattern corresponding with macrophyte abundances. This will indicate that M. californianus consume large proportions of macrophyte carbon, while other possible food sources, such as phytoplankton, or terrestrially derived POM, make smaller contributions. However, in areas with reduced macrophyte abundances, M. californianus will increasingly utilize other available sources, resulting in a more mixed diet that is not dominated by macrophytes. This study will increase our understanding of food web inputs in the rocky intertidal of southern California at a time when production sources are changing and contribute to understanding M. californianus population fluctuations.