An American bullfrom is native to most eastern states, but considered invasive in the moutain west.
What causes deformities in frogs, toads, and other amphibians?
Malformed frogs first came to national attention in 1995. Since that time, reports of malformed frogs and other amphibians have increased dramatically. Malformations have been reported in at least 44 states and in more than 50 species of frogs and toads. Multiple limbs, missing limbs, and facial abnormalities are the main malformations seen.
Frog malformations are the result of environmental factors affecting development during early tadpole stages. The variations in malformation suggest multiple causes are involved in this worldwide problem; four major causes that have been identified include injuries from predators, a specific parasite (fluke), nutritional deficiencies, and contaminants.
Amphibians are good indicators of significant environmental changes. Amphibians, unlike people, breathe at least partly through their skin, which is constantly exposed to everything in their environment. Consequently, their bodies are much more sensitive to environmental factors such as disease, pollution, toxic chemicals, ultraviolet radiation, and habitat destruction. The worldwide occurrences of amphibian declines and deformities could be an early warning that some of our ecosystems, even seemingly pristine ones, are seriously out of balance.
Learn more: Amphibian Research and Monitoring Initiative (ARMI)
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What is the United States doing about amphibian deformity and decline issues?
In response to indications of worldwide declines in amphibian populations, Interior Department agencies were directed to initiate a national program of amphibian monitoring, research, and conservation. There is an urgent need to determine the scope and severity of the problem and to investigate causes. As a result, the USGS formed the Amphibian Research and Monitoring Initiative (ARMI). The main...
How many amphibian species are there in the United States?
More than 6,000 amphibian species exist worldwide, with approximately 300 of them found in the United States. The USGS is the lead agency for the Amphibian Research and Monitoring Initiative (ARMI) , a program of amphibian monitoring, research, and conservation that was established in response to the worldwide decline of amphibian species.
Why are amphibian populations declining?
Research 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. Though every region in the United States has suffered amphibian declines, threats differ among regions. They include: Human influence from the Mississippi River east, including the metropolitan areas of the Northeast and the...
American bullfrog close-up
An American bullfrom is native to most eastern states, but considered invasive in the moutain west.
What are the leading causes of frog declines and deformities?
Listen to hear the answer.
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- FAQ
What is the United States doing about amphibian deformity and decline issues?
In response to indications of worldwide declines in amphibian populations, Interior Department agencies were directed to initiate a national program of amphibian monitoring, research, and conservation. There is an urgent need to determine the scope and severity of the problem and to investigate causes. As a result, the USGS formed the Amphibian Research and Monitoring Initiative (ARMI). The main...
How many amphibian species are there in the United States?
More than 6,000 amphibian species exist worldwide, with approximately 300 of them found in the United States. The USGS is the lead agency for the Amphibian Research and Monitoring Initiative (ARMI) , a program of amphibian monitoring, research, and conservation that was established in response to the worldwide decline of amphibian species.
Why are amphibian populations declining?
Research 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. Though every region in the United States has suffered amphibian declines, threats differ among regions. They include: Human influence from the Mississippi River east, including the metropolitan areas of the Northeast and the...
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American bullfrog close-up
An American bullfrom is native to most eastern states, but considered invasive in the moutain west.
An American bullfrom is native to most eastern states, but considered invasive in the moutain west.
What are the leading causes of frog declines and deformities?Listen to hear the answer.
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