Invasive, Endangered, and Reintroduced Species

of Pennsylvania

By: Abbie Thrower

Endangered SpeciesA plant or animal species small in numbers

and is in endanger of becoming extinct.The most common reasons for

endangerment are as follows: overhunting, intentional extermination, destruction of habitat, pollution, and the introduction of invasive species.

Destruction of HabitatPolluted Habitat

Preventing Endangerment

One of the most common ways to prevent endangerment is to protect habitats by creating national parks, nature reserves, and wilderness areas. You could also replant forests and native plants.

Endangered Plants in PANortheastern Bulrush

The Bulrush is endangered because their habitat is threatened by water level, pollution, and excavation. The greatest threat is the destruction of its wetland habitat.

Virginia Spiraea

Impoundments, road construction, unmanaged recreational use of river corridors, industrial development, lack of watershed management, and uncontrolled development of river corridors threaten the spiraea.

Endangered Animals in PADelmarva Fox Squirrel

The primary reason of endangerment for the squirrel is loss of forested habitat, human development, predation, traffic mortality, and competition from gray squirrels.

Short-eared Owl

Suitable nesting habitats are extremely limited in PA and intense agriculture farmers make many potential areas unsuitable.

Yellow-bellied flycatcher

Some threats are changes in vegetation and reproductive capacity resulting from heavy metal amounts in the ecosystem. Mining in northern PA has eliminated some of the birds habitat.

Native, Introduced, and Invasive Species

Native Species- one that occurs naturally with respect to a particular ecosystem.

Introduced Species- Species whose existence in an area is due to human action or activity.

Invasive Species- An new species to an area whose introduction does or is likely to cause economic or environmental harm or harm to human health.

Invasive SpeciesFive of the most common reasons invasive

species get into the country are as follows: accident, ships, wood products, ornamental plants, and pet trade.

Four of the most common ways that invasive species effect our environment are as follows: create competition, change food webs, prevent native species form reproducing, and alter ecosystem conditions.

Invasive Animals in PAZebra Mussel, Dreissena polymorpha. They originated in Balkans, Poland. They have spread within all the Great Lakes. They threaten native fish and wildlife by reducing species of algae and microscopic aquatic animals that are important for the food chain in their introduced environments.

Hemlock Woolly Adelgid, Adelges tsugae. It was First described in western North America in 1924 and first seen in the eastern United States in 1951 near Richmond, VA. In their native environment, this species caused little to no damage to the hemlock trees they fed on, because the trees had built up an immunity to them. In their introduced environment, they cause up to ninety percent mortality in hemlock trees.

Invasive Animals in PAEuropean Corn Borer, Ostrinia nubilalis. This insect came from Europe on a ship most likely bearing corn. In its 79 years in America the European corn borer has spread into Canada, into the Rocky Mountains, and south to Florida and New Mexico. The corn borers damage or kill corn by digging through the shank, cob, and/or kernels. They make farmers lose more than 1 billion dollars annually.

Invasive Plants in PAGarlic mustard, Alliaria petiolata. The garlic mustard originated in Europe as a vitamin rich winter herb. It was brought over by settlers. It has spread through southern and western PA. It grows earlier in the spring than native plants and prevents their growth. It will also crowd out growing plants.

Canada Thistle, Cirsium arvense. It was introduced to the U.S.A in the 1600’s. It is native to Europe. The thistle came accidentally through farm seed shipments. It crowds out native species and reduces crop yield. Its growth stops when temperature exceeds 85o F for extended periods.

Reintroduced and Extirpated Species

Reintroduced Species- Attempts made to prevent the extinction of threatened species and populations by reintroducing them in their natural habitat.

Extirpated Species- The local disappearance of a species, as opposed to extinction.

Reintroduced to PAElk Species

Between 1913 and 1926 the Pennsylvania game commission released 117 elk into Pennsylvania state forests. They introduced the Rocky Mountain Elk, taken from Wyoming and South Dakota, which is not the original elk species in PA, but share mostly the same roles and niches in the environment. So far, the elk are doing no damage to the habitat.

Works CitedEndangered Specieshttp://www.thefreedictionary.com/endangered+species

Endangered Species Need Your Help! http://www.endangeredspecie.com/Ways_To_Help.htm

U.S. Fish and Wildlife Servicehttp://www.fws.gov/midwest/endangered/plants/smallwhorledpogoniafs.html

Pennsylvania Game Commissionhttp://www.portal.state.pa.us/portal/server.pt?open=514&objID=621014&mode=2

Invasive Species Glossary of Termshttp://www.invasivespecies.org/resources/Glossary.html

Environmental Global Issues Maphttp://www.mhhe.com/biosci/pae/es_map/articles/article_66.mhtml

Invasive Species in PAhttp://www.defenders.org/resources/publications/invasives/pennsylvania.pdf

Iowa State University: Department of Entology http://www.ent.iastate.edu/pest/cornborer/insect

United States Department of Agriculturehttp://www.invasivespeciesinfo.gov/plants/canthistle.shtml