Scientists in ARMI, a program started by Congress in 2000 in response to concerns about amphibian declines, have been working to unravel the ups and downs of amphibian populations to support effective conservation and resource management decisions. To do this, ARMI scientists and field crews monitor the status of amphibians, research the causes of declines, and scientifically evaluate projects undertaken to sustain these species and their habitats across the country.
Pond life it's not easy being green!
ARMI scientists looked at a range of amphibian species found in the Southeast and posed the question, "What will happen to their populations under a scenario of changes in rainfall patterns more deluges alternating with droughts - which is being predicted by current climate models?"
It turns out that understanding how climate affects amphibians requires "thinking like the ponds" in which they live. Amphibians have unique life cycles most alternate between living in water as juveniles, to maturing and dispersing on land, then returning to water again as adults to mate and lay eggs.
When USGS scientists reviewed what was known about amphibian responses to rainfall, it turned out that both extremes in rainfall drought and heavy rainfall events can decrease the number of amphibians. The amphibians' response depends on a balance between these two key factors. If ponds dry up while aquatic juveniles are developing, survival of the next generation is lowered. However, if a deluge occurs at that time, nearby pools that often contain fish will be physically connected with the pools containing juvenile amphibians, and the fish will eat the juveniles.
In essence, the study showed that extreme rainfall events are key to predicting amphibian responses to climate, because such events affect the amount and
|Contact: hannah hamilton|
United States Geological Survey