Journal Article

Do Frogs Get Their Kicks on Route 66? Continental U.S. Transect Reveals Spatial and Temporal Patterns of Batrachochytrium dendrobatidis Infection

Lannoo, Michael J., Petersen, Christopher, Macallister, Irene, Nanjappa, Priya, Lovich, Robert E., Mitchell, Joseph C., Phillips, Christopher

2011

Overview

The chytrid fungus Batrachochytrium dendrobatidis (Bd) has been devastating amphibians globally. Two general scenarios have been proposed for the nature and spread of this pathogen: Bd is an epidemic, spreading as a wave and wiping out individuals, populations, and species in its path; and Bd is endemic, widespread throughout many geographic regions on every continent except Antarctica. To explore these hypotheses, we conducted a transcontinental transect of United States Department of Defense (DoD) installations along U.S. Highway 66 from California to central Illinois, and continuing eastward to the Atlantic Seaboard along U.S. Interstate 64 (in sum from Marine Corps Base Camp Pendleton in California to Naval Air Station Oceana in Virginia). We addressed the following questions: 1) Does Bd occur in amphibian populations on protected DoD environments? 2) Is there a temporal pattern to the presence of Bd? 3) Is there a spatial pattern to the presence of Bd? and 4) In these limited human-traffic areas, is Bd acting as an epidemic (i.e., with evidence of recent introduction and/or die-offs due to chytridiomycosis), or as an endemic (present without clinical signs of disease)? Bd was detected on 13 of the 15 bases sampled. Samples from 30 amphibian species were collected (10% of known United States' species); half (15) tested Bd positive. There was a strong temporal (seasonal) component; in total, 78.5% of all positive samples came in the first (spring/early-summer) sampling period. There was also a strong spatial component--the eleven temperate DoD installations had higher prevalences of Bd infection (20.8%) than the four arid (<60 mm annual precipitation) bases (8.5%). These data support the conclusion that Bd is now widespread, and promote the idea that Bd can today be considered endemic across much of North America, extending from coast-to-coast, with the exception of remote pockets of naïve populations.

• Publisher: Public Library of Science
• Subject: Acris crepitans blanchardi / Air bases / Amphibia / Amphibians / Animals / Annual precipitation / Anura - microbiology / Aridity / Armed forces / Batrachochytrium dendrobatidis / Biodiversity / Biology / Chytridiomycosis / Chytridiomycota - physiology / Disease control / Disease transmission / Earth Sciences / Endangered & extinct species / Epidemics / Frogs / Geography / Health aspects / Humans / Hydrologic data / Hypotheses / Infections / Models, Biological / Mycoses - microbiology / Mycoses - transmission / Natural resources / Pathogens / Population / Populations / Rain / Reptiles & amphibians / Seasons / Species / Species Specificity / Temperature / Time Factors / Transportation / United States / United States Department of Defense