Foreign Species take the United States by Storm

A 1999 Cornell University study estimates that the US spends $137 billion a year attempting to keep invasive species under control. Invasive species are a growing problem in the United States. The World Conservation Union defines an invasive species as “organisms (usually transported by humans) which successfully establish themselves in, and then overcome, otherwise intact, pre-existing native ecosystems.” Many of these species are set free by disenchanted pet owners, or are carried by foreign boats. According to the June 3, 2004 release by National Geographic News, in the past five years, “the U.S. has imported more than 144,000 Burmese pythons. Hatchlings sell for as little as U.S. $20.” These babies may be fun, but when they grow to 15 feet, many owners are not so pleased, and dump them into the water, rather than selling them to pet stores. Since the mid-1990’s, Everglade National Park rangers have killed or captured more than 90 Burmese pythons. Recently, Burmese pythons have been in the news for wreaking havoc on the Florida Everglades. In February, tourists to the Pa-hay-okee Overlook in Everglade National Park witnessed a battle between a python and an alligator. The python managed to escape after being locked in the alligator’s jaws for over 24 hours. This was not the first, nor the last, of intense battles between this foreign and domestic species. For now, National Geographic reports that the alligators are holding their own, although this appears to be changing. Florida’s Everglade National Park is becoming overrun with Burmese pythons, which can grow to a shocking 20 feet long. These pythons are among the largest snakes in the world. Pythons are not the only creatures taking the United States by storm. Zebra mussels have been a growing problem throughout the United States. These freshwater mussels, introduced to the Great Lakes in 1986, will attach themselves to pretty much anything that stands still long enough. This means they can clog pipes of factories that use fresh water, as well as cling to boats and docks. According to research done at Wayne State University in Detroit, zebra mussels have killed off nearly all mussels native to Lake Erie. They reproduce at a young age, release large amounts of sperm and eggs, and their dense numbers allow for a high fertilization rate. They are now being sighted all along the Mississippi River. The Japanese Shore Crab, also called the Asian Shore Crab, was first sited in New Jersey in 1988. They are omnivorous, eating both living and dead invertebrates, snails, algae, barnacles, and mussels. About the size of a silver dollar, it is now the most common inter-tidal crab found in southern New England. Director of the US Fish and Wildlife Services, Steven A. Williams, believes that invasive species are the number one environmental threat to the US. National Geographic reports that invasive species are second only to habitat loss in causing the endangerment and extinction of native species. San Francisco Bay is now home to an estimated 260 foreign species, reports National Geographic. For instance, the African clawed frog, which is native to Kenya. These frogs eat almost anything they can get their claws on- including insects, fish, and birds. The only way to keep such an animal from spreading is to kill it, which would cost California millions of dollars. Animals aren’t the only invasive species. The United States Department of the Interior estimates that 100 million acres of US land are infested with invasive plants. Plants are especially damaging because they have the ability to alter entire ecosystems. According to The United States National Arboretum, invasive plants produce large numbers of plants each season, spread efficiently, usually by wind, water, or animals, grow rapidly, spread rampantly when unchecked, and tolerate many different soil types and weather conditions. Aquatic plants, such as the water hyacinth, can completely suffocate native plant species. Originally from South America, this plant is now found in nearly 50 countries around the world. Its population can double in 12 days, reports the World Conservation Union. The WCU’s website reports the water hyacinth as one of the worlds 100 most invasive species. The Australian pine tree, now a problem in South Florida, is salt water resistant. It has shallow roots, which mean they topple easily in rough winds, suffocating native plant species, and causing an especially damaging obstacle for Atlantic loggerhead turtles which nest on the beaches of Florida. The water plant Hydrilla, is a growing problem in Connecticut. It first appeared in Stonington, CT in 1985. As of 2001, Hydrilla has been found in a few large ponds throughout CT, and has recently been reported in Barnstable Massachusetts. This plant grows on the bottom of freshwater ponds at a rapid pace, drowning out native plant and animal species. Each pond had been treated at time of discovery, yet more were found. For a detailed list of New England invasive species, visit the Invasive Plant Atlas of New England’s website at http://invasives.eeb.uconn.edu/ipane.