Frequently Asked Questions

Biology and Ecosystems

USGS science is used by other agencies to help conserve species, lands, resources, and priority ecosystems.

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A Black-capped Chickadee with a severely deformed beak where the upper beak is elongated and curved down while the lower beak is
Some of the potential causes of beak deformities (Avian Keratin Disorder) found in black-capped chickadees and other birds include: contaminants, nutritional deficiencies (such as low vitamin D3 or Calcium/Phosphorus), diseases, parasites, blunt trauma, genetic abnormalities, and viruses.  However, from these potential causes we have not found any...
Image: Brown Bat
Bats can be found in almost all parts of the world and in most regions of the United States. In general, bats seek out a variety of daytime retreats such as caves, rock crevices, old buildings, bridges, mines, and trees. Different species require different roost sites. Some species, such as the Mexican free-tailed and gray bats live in large...
Image: Burmese Python Swimming in Florida Bay
A number of Burmese pythons have been found on Key Largo, and a few in the Lower Keys. However, there is as yet no evidence of a breeding population anywhere in the Keys. Because pythons regularly escape or are released from captivity, it can be difficult to determine whether a snake encountered in the Keys arrived there by swimming from the...
Image: An Invasive Boa Constrictor at a Miami County Park
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 illegal releases, but most of these have not established reproductive populations. Florida is a major transportation hub and has a climate that’s suitable for many invasive species. As a...
Image: Black-bird die-off Investigation
A cluster of sick or dead animals in an area may indicate a wildlife disease of concern. If you find sick or dead wildlife, contact your closest state or federal wildlife agency that may want to investigate some of these incidents. You may also want to contact your local health department to report this occurrence.
Close-up view of a brown, empty shell that looks exactly like a live cicada, complete with antennae and individual hairs
The broods (hatchlings produced at the same time) of periodical cicadas (species in the genus Magicicada), and the locations and years of adult emergence, are well documented on the University of Michigan’s Periodical Cicadas Web page. 
Image: Cicada (Magicicada sp.)
Cicadas make a variety of sounds, including very loud buzzing sounds. The males have tymbal organs that include rib-like bands on a membrane that can be vibrated very rapidly by a special muscle. The sounds include courtship calls  and squawking sounds when the cicada is handled or disturbed.
Image: Cicada (Magicicada sp.)
Cicadas are insects in the order Homoptera, and they are related to planthoppers and aphids. They have piercing-sucking mouthparts, which they use to pierce plants and suck out the plant juices. Immature cicadas live underground for years, where they feed on plant roots. Adults live aboveground, typically for about a month, where they mate and lay...
Image: Cicada (Magicicada sp.)
Cicadas are not harmful to humans and they rarely cause significant plant damage. However, the eggs are laid in slits in twigs, so during large emergences of periodical cicadas they can cause substantial damage to branches of trees and shrubs.
Image shows a male white-tailed deer facing to the left of the image.
Chronic wasting disease (CWD) has an extended incubation period averaging 18–24 months between infection and the onset of noticeable signs. During this time frame animals look and act normal. The most obvious sign of CWD is progressive weight loss. Numerous behavioral changes also have been reported, including decreased social interaction, loss of...
Image shows a mule deer doe walking on grass, facing right
Chronic wasting disease is caused by a misfolded protein called a prion. All mammals produce normal prions that are used by cells, then degraded and eliminated, or recycled, within the body. When disease-associated prions contact normal prions, they cause them to refold into their own abnormal shape. These disease-associated prions are not readily...
Fish swim around a brightly colored coral reef
Coral reefs can be damaged by natural processes, such as storms, but they are increasingly at risk from human activities. Oil spills and pollutants can threaten entire reefs. Excessive nutrients from land sources, such as sewage and agricultural fertilizers, promote the growth of algae that can smother corals. Other organisms harmful to corals,...