Temporal and interspecific variation of the amphibian chytrid fungus Batrachochytrium dendrobatidis in northwest Pennsylvania

Billet, Logan

Temporal and interspecific variation of the amphibian chytrid fungus Batrachochytrium dendrobatidis in northwest Pennsylvania

Persistent URL

http://hdl.handle.net/10456/42702

Author(s)

Billet, Logan

Date Issued

April 3, 2017

Abstract

The abundance of parasites varies through time and among species, and is often associated with environmental factors (e.g. temperature) and host life-history traits (e.g. developmental rate). The amphibian chytrid fungus, Batrachochytrium dendrobatidis (Bd), is one of the primary drivers of amphibian population declines and extinctions around the world. Like many parasites, Bd has temperature-dependent growth and amphibian species vary in their resistance to Bd, both of which could affect Bd prevalence in populations. To understand seasonal Bd dynamics in populations of amphibians, I conducted field surveys throughout the fall in northwest Pennsylvania. I tested for temperature-driven temporal patterns of Bd prevalence and infection intensity in green frog (Lithobates clamitans) and bullfrog (Lithobates catesbeianus) tadpoles at 2 ponds from September 23 – November 27 2016. I also recorded body length of each tadpole to assess for variation in Bd infection throughout tadpole development. Water temperature was a significant negative predictor of Bd infection prevalence in bullfrogs and a marginally significant negative predictor of Bd infection prevalence in green frogs. Length was a significant positive predictor of Bd infection prevalence and intensity in bullfrogs but not in green frogs. These results emphasize the importance of considering species identity and developmental stage when surveying for Bd and suggest that like in other regions, temperature is a driver of Bd prevalence fluctuations in northwest PA.

Major

Biology

First Reader(s)

Venesky, Matthew D.