FAQs

Eradicating an established population of invasive carp would be extremely difficult and expensive, if possible at all. Potential control methods include the use of fish poisons, physical barriers, physical removal, habitat alteration, or the addition of predators, parasites, or pathogens. Research on invasive carp control is ongoing and documents on the subject are provided through the Invasive...

Carp are not native to North American waters, but various carp species have been introduced here since the mid-1800s, much to the detriment of native fish. Although carp eradication measures have been active for over 100 years, long-established species, like the common carp, are present in almost every state. Invasive carp (bighead, black, grass, and silver carp) were imported to the United States...

Swamp eels are freshwater fish, but they are not closely related to other living eels or snake-like marine and freshwater fishes. In addition to the name swamp eel, other English common names used for members of this group of fish include rice eel, rice-paddy eel, and belut. The swamp eel family includes more than a dozen species. Asian swamp eels may be confused with a number of native animals...

By eating insects, bats save U.S. agriculture billions of dollars per year in pest control. Some studies have estimated that service to be worth over 3.7 billion dollars per year, and possibly as much as 53 billion dollars per year. This value does not, however, take into account the volume of insects eaten by bats in forest ecosystems and the degree to which that benefits industries like lumber...

Free-ranging snakes representing dozens of species from around the world are discovered in the United States in any given year, usually as a result of escapees or releases from the pet trade, but most of these don't appear to have established a reproductive population. Any animal can be problematic when released in places where it is not native. For example, the Brown Treesnake was introduced to...

An invasive species is an introduced, nonnative organism (disease, parasite, plant, or animal) that begins to spread or expand its range from the site of its original introduction and that has the potential to cause harm to the environment, the economy, or to human health. A few well-known examples include the unintentional introduction of the West Nile virus, chestnut blight, the South American...

No, bats are not blind. Bats have small eyes with very sensitive vision, which helps them see in conditions we might consider pitch black. They don’t have the sharp and colorful vision humans have, but they don’t need that. Think of bat vision as similar to a dark-adapted Mr. Magoo (a cartoon character with very poor vision). Learn more at the USGS North American Bat Monitoring Program (NABat)...

Yes, but not in most of the United States. Of the three species of vampire bats in North America, only a single specimen has been recorded for the United States in extreme southwest Texas. Vampire bats do not suck blood--they make a small incision with their sharp front teeth and lap up the blood with their tongue. Vampire bats in Mexico and South America feed on the blood of livestock such as...

Bats are the most significant predators of night-flying insects. There are at least 40 different kinds of bats in the U.S. that eat nothing but insects. A single little brown bat, which has a body no bigger than an adult human’s thumb, can eat 4 to 8 grams (the weight of about a grape or two) of insects each night. Although this may not sound like much, it adds up—the loss of the one million bats...

All healthy bats try to avoid humans by taking flight and are not purposely aggressive. Most bats are about the size of a mouse and use their small teeth and weak jaws to grind up insects. You should avoid handling bats because several species, such as the hoary and big brown bats, have large teeth that can puncture skin if they are handled improperly. Less than one percent of the bat population...

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...

Although extinctions occur naturally, the current rate of plant and animal extinctions is much higher than the natural or historical rates. Habitat loss is the primary cause of higher extinction rates. Other causes include habitat changes, over-exploitation of wildlife for commercial purposes, the introduction of harmful nonnative species, pollution, and the spread of diseases. Learn more...