Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Endangered frogs coexist with fungus once thought fatal

05.10.2004


Worldwide amphibian declines have reached crisis proportions. In many areas, habitat loss is the likely culprit but, in 1996, it was suggested that some unknown disease had spread through the populations. In 1998, the fungus Batrachochytrium dendrobatidis was identified from sick and dead frogs and, since then, several lines of laboratory based evidence have suggested that B. dendrobatidis is to blame for the dramatic frog declines. But with little information about how the disease impacts frogs in the wild, the causal role of this chytrid fungus remains unclear. In the open access journal PLoS Biology, Australian researchers Richard Retallick, Hamish McCallum and Rick Speare now "show unequivocally" that remaining populations of T. eungellensis, a rainforest frog listed as endangered, can persist in the wild with stable infections of this fungus.




To evaluate the effects of the fungus on frogs in their natural habitat, the authors focused on six species living in the high-elevation rainforest streams of Eungella National Park in Queensland, Australia, where frog losses were "particularly catastrophic". Two species vanished between 1985 and 1986: the Eungella Gastric-Brooding Frog (Rheobatrachus vitellinus), which is now thought extinct, and the Eungella Torrent Frog (Taudactylus eungellensis), which later reappeared in a few small populations. In the PLoS Biology study, Retallick et al. tested tissue samples taken from frogs between 1994 and 1998 - before the disease had been identified. The marked frogs were released back into the wild at the time the samples were collected. The authors found fungal infections in the samples of two species, including T. eungellensis. An analysis of tissue from recaptured frogs during the same period showed that the prevalence of infection did not vary from year to year, suggesting that the infection is now endemic. McCallum and colleagues also found no evidence that survival differed between infected and uninfected frogs, suggesting that this potentially devastating amphibian disease now coexists with the frogs, with little effect on their populations.

While these findings do not exonerate the fungus as the agent of mass declines, they can rule out the possibility that the fungus caused the decline, then vanished from the area, allowing frog populations to recover. Although it’s possible that B. dendrobatidis did not cause the initial T. eungellensis declines, surviving frog populations may have developed resistance to the pathogen, or less virulent strains of the fungus may have evolved. If it turns out that frog populations can develop resistance to the chytrid fungus, the researchers point out, then a conservation program of captive breeding and selecting for resistance could potentially thwart the extinction of these, and other, critically endangered frogs.

Paul Ocampo | EurekAlert!
Further information:
http://www.plos.org

More articles from Life Sciences:

nachricht Seeing on the Quick: New Insights into Active Vision in the Brain
15.08.2018 | Eberhard Karls Universität Tübingen

nachricht New Approach to Treating Chronic Itch
15.08.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

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....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
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

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

Unraveling the nature of 'whistlers' from space in the lab

15.08.2018 | Physics and Astronomy

Diving robots find Antarctic winter seas exhale surprising amounts of carbon dioxide

15.08.2018 | Earth Sciences

Early opaque universe linked to galaxy scarcity

15.08.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>