The fungal disease chytridiomycosis has ravaged amphibian populations, including contributing to several extinctions. But new research may bring some hope for currently threatened amphibians.
New evidence from Jonathan Q. Richmond of the US Geological Survey shows that individual amphibians may be able to develop resistance to the disease. The study published in Bioscience suggests that further research should be done to investigate possible acquired immunity, since it may be helpful in predicting the spread of the disease and developing better ways to protect endangered amphibian populations.
To show that some amphibians can develop immunity, Richmond and colleagues point to studies indicating that two species of frogs in New Zealand showed resistance to re-infection after being infected with the fungus that causes chytridiomycosis, known as Batrachochytrium dendrobatidis , and then treated with the drug chloramphenicol. Another study showed that the environment where infection occurred could impact resistance: North American toads infected in dry areas survived longer when re-infected in wet conditions than toads first affected in wet conditions.
Richmond and his colleagues believe that innate immunity must be activated in order to protect the individual from the disease. Further studies of the process of activation could prove vital for saving amphibian populations across the world.
(02/09/2009) Salamanders in Central America like frogs, toads, and other amphibians at sites around the world are rapidly and mysteriously declining, report researchers writing in the journal Proceedings of the National Academy of Sciences. Disturbingly, salamanders are disappearing from protected areas and otherwise pristine habitats.
(12/01/2008) The Neotropics harbor between 30-50% of the world’s reptiles and amphibians, but dramatic declines in both groups have been observed over recent decades. While a number of factors have been cited, many of the causes of reptile and amphibian declines are still poorly understood. The situation is paralleled by a lack of information of the natural history, ecology, and behavior of many species.
(11/28/2008) Amphibians worldwide are in trouble. One of the most endangered animal groups, amphibians are increasingly threatened by habitat loss, pollution, and climate change. However the largest threat is chytridiomycosis, a devastating disease caused by a parasitic chytrid fungus known as Batrachochytrium dendrobatidis, otherwise known as Bd.
(11/13/2008) Frogs, toads, salamanders and other amphibians are disappearing at an alarming rate. Of approximately 6,000 amphibian species in the world, about one third are classified as threatened or endangered. A disease caused by a chytrid fungus has devastated frogs living in mid to high elevation streams worldwide. Amphibians also face habitat destruction as forests and wetlands are developed and polluted by agricultural chemicals. In Panama, highland frog populations west of the Canal have declined at an alarming rate.
(11/13/2008) Scientists have yet to conclusively explain the underlying cause of global declines in amphibian populations, according to a study published in the journal Proceedings of the National Academy of Sciences. The research says that two leading theories for the demise of amphibians — both related to the emergence and spread of the deadly chytrid fungus — are not supported by scientific data.