Biology Projects 2011
Diversity of microcrustaceans in ponds of the Southern San Joaquin Valley and the foothills of the Sierra Nevada (CA)
Faculty Mentor - Dr. Antje Lauer
Batrachochytrium dendrobatidis (Bd) is a fungal pathogen that has been identified as the cause in the massive decline of
various amphibian species worldwide. Along with the decline of other species in the foothills of the Sierra Nevada due to
Chytridiomycosis, the mountain yellow legged frog (Rana muscosa) is severely threatened by Bd in the higher Sierra Nevada (CA).
Also, a decline of diverse microcrustacean species, which are natural predators of Bd, has been observed in some areas in the
Sierra Nevada Mountains (e.g. Lake Tahoe. Microcrustaceans can also produce dormant, diapausing eggs during adverse environmental
conditions that can lie dormant in sediment for decades until conditions improve and can serve as an indicator for the diversity
of Microcrustaceans in the past. By investigating the water and sediment of ponds and lakes with microscopy and molecular biotechnological
methods, we want to determine the presence of Bd in the watercolumn and also analyze the status quo of Microcrustaceans in the
presence and past.
Do bacteria found on the skin of the North American Bullfrog (Rana catesbeiana)
play a role in protecting it from the fungal pathogens?
Faculty Mentor - Dr. Kathleen Szick-Miranda
This study focuses on the bacterial diversity found on the skin of the Northern American Bullfrog Rana catesbeiana, an
invasive species in California that is able to successfully outcompete other native amphibian species. One reason that explains
its success is that it is immune to a variety of amphibian diseases including Chydridiomycosis, a skin disease caused by a fungus
known as Batrachochytrium dendrobatidis (Bd). Chytridiomycosis is responsible for major amphibian declines worldwide. The reasons
why the bullfrog can get infected, but does not succumb to the disease are not known. Recent research suggests that resident skin bacteria
can play a role in protecting amphibians against Bd. Our study focuses on the antifungal ability of the cutaneous bacteria of
R. catesbeiana isolated from both adults and juveniles (tadpoles). Participants in this research project will test bacteria, isolated
from bullfrog skin, on their antifungal capability against potentially pathogenic fungi. In addition, participants will learn the
fundamentals of research design, analysis and interpretation. The data collected from this project may have the potential to widely
impact global amphibian conservation as well as human health issues by identifying probiotics that can lead to the discovery of potential
antibiotics or novel chemotherapeutic compounds in the future.
| These Web pages and any associated Adobe Acrobat Files are designed as supporting material
for the respective projects. Please feel free to contact either of the program directors with any
questions you might have.