Discipline: Ecology Environmental and Earth Sciences
Subcategory: Ecology
Session: 1
Room: Park Tower 8206
Cameron S. Lockett - Virginia State University
Batrachochytrium dendrobatidis (Bd), chytrid fungus is a calamitous panzootic. Bd has infected approximately 700 species of amphibians and led to the decline or extinction of over 200 species. Bd infects the keratin-containing layers of amphibian skin comprising osmotic regulation which may lead to death. Fungal spread is through water-borne spores from infected individuals or direct contact between infected individuals. In South America Bd has been detected in nine of 12 countries. There has been no extensive testing for the presence of Bd in Suriname. Suriname shares a contiguous border with Brazil, and is separated from French Guyana by a river. Frogs from both Brazil and French Guiana have tested positive for the Bd. Therefore, we tested two hypotheses: 1) People are responsible for the transport of Bd by carrying the fungus spores on their clothing or shoes from infected to non-infected regions.2) Rivers may be a barrier to the spread of Bd. We combined our Bd survey data from 10 different geographic locations visited in 2015 and 2018. To test the first hypothesis we sampled frogs at locations with heavy human impact and remote uninhabited regions. To test the second hypothesis we sampled frogs from remote rain forest areas on the Surinamese side of the Maroni River across from French Guiana where frogs were found to have been infected with Bd. Frogs were captured by hand using a sterile disposable glove for each frog. Frogs were swabbed with Q-tip 25 times by rubbing the venter, hind-legs and feet. The swab was then placed in 90% ethanol in a sterilized 1.5 mm vial. Individuals were identified to species and sex. Then data was collected on geographic location, date, time, and snout-vent length to the nearest mm and mass to the nearest 0.01 g. Swab samples were analyzed by Pisces Molecular laboratories for DNA/RNA analysis of Bd presence. Frogs were released at the site of their capture after swabbing. 157 frogs representing 29 genera of frogs tested negative for Bd. In conclusion, Bd has not been currently found in central, northern and eastern regions of Suriname. No support was found for the first hypothesis. However, the second hypothesis received initial support. Future research would involve determining if Bd has reached the Maroni River in French Guiana. We also plan to test the western region of Suriname, which has not been tested. The results of this research are important in providing data on one of the last countries in South America, not infected with Bd. The data will contribute to the timeline of how the disease spreads and can be used in later efforts to help with conservation of frogs from Bd.
References: Berger, L., et al., 1998. Chytridiomycosis causes amphibian mortality associate with population declines in the rain forests of Australia and Central America. Proc. Natl. Acad. Sci. U.S.A. 95:9031-9036.
O?Hanlon S. et al., 2018. Recent Asian origin of chytrid fungi causing global amphibian declines. Science 360:621-627.
Funder Acknowledgement(s): Funder Acknowledgement(s): This study was aided by Rawien Jairam and Raissa Tche’tcho Kemajou with their help in the field. Funding was provided by a NSF/HBCU-UP grant to Christian d’Orgeix.
Faculty Advisor: Christian d'Orgeix, cdorgeix@vsu.edu
Role: I was in the field in Suriname were I: caught, sampled, and released frogs. I have read scientific papers on the subject. I have also written the abstract presented here.