Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Outbreak: Rapid appearance of fungus devastates frogs, salamanders in Panama

08.02.2006


Something wicked this way comes, if you’re a frog or salamander living near El Cope, Panama.

An outbreak of an infectious disease called chytridiomycosis, attributed to the fungus Batrachochytrium dendrobatidis, has infected and caused rapid die-offs in eight families of Panamanian amphibians, scientists report in this week’s issue of the Proceedings of the National Academy of Sciences (PNAS).

A survey of amphibian populations in central Panama has uncovered a case of chytridiomycosis that is rapidly radiating outward from western Panama into the El Cope region, spreading from northwest to southeast from Costa Rica toward Colombia.



"Chytridiomycosis is an alarming model system for disease-driven extinction of a high proportion of an entire class of vertebrates," the scientists write in PNAS. "It is no longer correct to speak of global amphibian declines, but more appropriately of global amphibian extinctions."

The fungus has been implicated in the decline of more than 40 amphibian species in Central America and 93 such species worldwide. But few researchers have been able to detect and monitor the presence of the fungus before a disease outbreak, and then witness the impact of an epidemic as it occurred, said zoologist Karen Lips of Southern Illinois University Carbondale, lead author of the report.

"We anticipated the eastward movement of the fungus, and chose a fungus-free study site near a previously infected area," she said. "Indeed, the fungus found its way there, and when it did, it quickly caused local amphibian extinctions and devastated frog and salamander biodiversity."

Pathogens, or disease-causing microbes, "rarely cause extinctions in the species they infect," said James Collins, assistant director of biological sciences at the National Science Foundation (NSF). Collins is on leave from Arizona State University, and is a co-author of the paper. "There are only a few examples where we think a pathogen resulted in extinction of a species in an area. This is one of them."

The rockhopper frog, for example, which lived along El Cope riverbanks, disappeared completely within one month. Chytridiomycosis wasn’t detected at the El Cope study site, said Collins, until Sept. 23, 2004, when scientists found the first infected frog. From then through mid-Jan. 2005, the fungus went on a rampage, killing so many frogs within 4 months that amphibian abundance was reduced by more than 50 percent.

Dead frogs included individuals in 38 species (57 percent of the amphibian species at the site). All but three of the dead amphibians were infected with chytridiomycosis, and six of seven samples from substrates like stream boulders tested positive for the fungus, the researchers report.

"None of the 1,566 individuals of 59 amphibian species sampled before Sept. 2004, was infected with this fungus," said Lips. "Our results demonstrate that the prevalence of the fungus very rapidly went from zero to high at this site." The timing of the outbreak, said Collins, "indicates that chytridiomycosis is rapidly moving southeastward, allowing us to predict its entry into amphibian communities in central Panama."

When the disease emerges at a site, it is thought to spread through a combination of frog-to-frog and environment-to-frog transmission. In the lab, some species of amphibians can carry the infection for up to 220 days before dying. The die-off at El Cope occurred during the peak of the rainy season. Many mountain-dwelling frogs in the New World tropics make their way to water bodies to breed during the region’s prolonged rainy season, thereby transmitting the waterborne fungus.

"Our findings definitively link the appearance of chytridiomycosis to amphibian population declines," said Lips. The area had no evidence of climate anomalies in 2004; its temperature and rainfall patterns were similar to those found in long-term records. "These results support a model of amphibian declines in which this fungus enters and quickly spreads through a community with no previously infected individuals," Lips said.

The researchers predict the loss of many more amphibian species from the region, most likely from mountainous areas directly east of the study site.

To the west, the fungus has already left countless dead amphibians in its wake.

Cheryl Dybas | EurekAlert!
Further information:
http://www.nsf.gov

More articles from Ecology, The Environment and Conservation:

nachricht Waste in the water – New purification techniques for healthier aquatic ecosystems
24.07.2018 | Eberhard Karls Universität Tübingen

nachricht Plenty of habitat for bears in Europe
24.07.2018 | Deutsches Zentrum für integrative Biodiversitätsforschung (iDiv) Halle-Jena-Leipzig

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: It’s All in the Mix: Jülich Researchers are Developing Fast-Charging Solid-State Batteries

There are currently great hopes for solid-state batteries. They contain no liquid parts that could leak or catch fire. For this reason, they do not require cooling and are considered to be much safer, more reliable, and longer lasting than traditional lithium-ion batteries. Jülich scientists have now introduced a new concept that allows currents up to ten times greater during charging and discharging than previously described in the literature. The improvement was achieved by a “clever” choice of materials with a focus on consistently good compatibility. All components were made from phosphate compounds, which are well matched both chemically and mechanically.

The low current is considered one of the biggest hurdles in the development of solid-state batteries. It is the reason why the batteries take a relatively long...

Im Focus: Color effects from transparent 3D-printed nanostructures

New design tool automatically creates nanostructure 3D-print templates for user-given colors
Scientists present work at prestigious SIGGRAPH conference

Most of the objects we see are colored by pigments, but using pigments has disadvantages: such colors can fade, industrial pigments are often toxic, and...

Im Focus: Unraveling the nature of 'whistlers' from space in the lab

A new study sheds light on how ultralow frequency radio waves and plasmas interact

Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

LaserForum 2018 deals with 3D production of components

17.08.2018 | Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

 
Latest News

A paper battery powered by bacteria

21.08.2018 | Power and Electrical Engineering

Protein interaction helps Yersinia cause disease

21.08.2018 | Life Sciences

Biosensor allows real-time oxygen monitoring for 'organs-on-a-chip'

21.08.2018 | Medical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>