New U.S. Geological Survey-led research [sciencedaily.com] suggests that even though amphibians are severely declining worldwide, there is no smoking gun -- and thus no simple solution -- to halting or reversing these declines.
"Implementing conservation plans at a local level will be key in stopping amphibian population losses, since global efforts to reduce or lessen threats have been elusive," said Evan Grant, a USGS research wildlife biologist who led the study published in Scientific Reports today. "This research changes the way we need to think about amphibian conservation by showing that local action needs to be part of the global response to amphibian declines, despite remaining questions in what is causing local extinctions."
The evidence shows that though every region in the United States suffered declines, threats differed among regions.
They include:
- Human influence from the Mississippi River east, including the metropolitan areas of the Northeast and the agricultural-dominated landscapes of the Midwest
- Disease, particularly a chytrid fungus in the Upper Midwest and New England
- Pesticide applications east of the Colorado River
- Climate changes across the Southern U.S. and the West Coast
Amphibian declines are a global phenomenon that this new research demonstrates has continued unabated in the United States since at least the 1960's, and which are occurring even in protected national parks and refuges. Scientists have broadly linked declines to environmental factors like climate, human influence such as land-use change, and contaminants and disease, but have not been able to use actual scientific data on a large scale to discern causes of the ongoing disappearance of amphibian populations.
They forgot the other threat, Doc Hopper's Frog Legs [wikia.com].