Meeting Abstract
Amphibians are declining at an alarming rate. A recent IUCN assessment shows that one-third or more of known amphibians are threatened with extinction. Many of these declines are due to the disease chytridiomycosis, which is caused by the fungal pathogen, Batrachochytrium dendrobatidis (“Bd”), and has been linked with declines and extirpations of over 200 species worldwide. Temperature strongly affects growth rates, replication and survival of Bd in vitro and in vivo. In the tropics, previous studies have suggested prevalence and intensity of Bd infection is greater at high elevation sites where temperatures are consistently low. However, these studies generally only look at prevalence in community assemblages, not a single species, and typically only at one time point, not across seasons. Also, little is known about the microhabitat conditions and how they vary across spatial and temporal scales at high and low elevation sites. We recently discovered that a highly susceptible species, the common rocket frog (Colostethus panamensis), is persisting with Bd infection in low-mid elevation sites but has not recovered in high elevation sites. We conducted field surveys, recorded microhabitat temperatures and collected diagnostic samples to determine infection intensity in this species at three sites along an altitudinal gradient and across seasons (wet and dry seasons). We used temperature loggers to characterized the seasonal patterns in microhabitat conditions and link patterns with infection data from our diagnostic samples. We suggest that microhabitat conditions may be a key factor driving infection dynamics and limiting recovery in this species at high elevation sites. These findings will provide a better understanding of broad patterns seen on a global scale and provide insights for local management of amphibian health and conservation.
