When an object rests on a surface, such as a table, for example, the downward force it applies to the surface is counteracted by an equal but upwards force, or reaction, applied by the surface. See more at Newton's laws of motion. A response to a stimulus, such as a reflex.
State. Aquatic Invasive Species: Snakehead (PDF | 201 KB). Indiana Department of Natural Resources. Northern Snakehead. Maryland Department of Natural Resources. Northern Snakehead Fish (Channa argus). New York Department of Environmental Conservation.
What is an invasive species? An invasive species is any non-native organism whose introduction can cause harm to the environment, human health or economic interests. Some of the invasive species on this website are already serious pests in North America, while others are not yet widespread. Invasive species are introduced through many means.