Problem pets: released into the wild, these animals can harm the environment.A baby Burmese python The Burmese Python (Python molurus bivittatus) is the larger subspecies of the Indian Python and one of the 6 biggest snakes in the world, native to rain forest areas of Southeast Asia. may look cute curled up in a pet-store aquarium. But anyone who takes one home may be in for a surprise. Skip Snow, a wildlife biologist ''' The examples and perspective in this article or section may not represent a worldwide view of the subject. Please [ improve this article] or discuss the issue on the talk page. A wildlife biologist is someone who studies wild animals and their habitats. in Everglades National Park, Florida, knows what happens to a Burmese python after a few years of good care. Full-grown, it can be 20 feet long and weigh more than 200 pounds (see photo, p. 8). Snow often spends days trying to capture the big snakes, which can be strong enough to take on alligators. "The python problem [in the Ever-glades] started with pet snakes," Snow says. "People let them go because they grew too big--or they escaped." In Southeast Asia Southeast Asia, region of Asia (1990 est. pop. 442,500,000), c.1,740,000 sq mi (4,506,600 sq km), bounded roughly by the Indian subcontinent on the west, China on the north, and the Pacific Ocean on the east. , the Burmese python's native environment, this would not have been a problem. In a stable, established ecosystem, every animal and plant species has what it needs to survive--but it also has natural predators to keep its numbers in check. When an animal or a plant species is introduced where it doesn't belong, a lack of natural predators can cause its numbers to increase rapidly. This throws the area's balance out of whack, bringing death and destruction to defenseless native species. That is what happened when pet owners released their Burmese pythons into the saw-grass marshes of South Florida. "The [pythons] are competing with other animals for food, space, burrows, crevices, and rocks," says Snow. South Florida is not the only place in the United States United States, officially United States of America, republic (2005 est. pop. 295,734,000), 3,539,227 sq mi (9,166,598 sq km), North America. The United States is the world's third largest country in population and the fourth largest country in area. that is struggling with former pets that have become invasive species
Invasive species is a phrase with many definitions. The first definition expresses the phrase in terms of non-indigenous species (e.g. . Here are some other problem critters. Nile Monitor The Nile monitor (Varanus niloticus) is a large member of the monitor lizard family (Varanidae). Nile monitors grow to about 6 to 7 feet in length. They have muscular bodies, strong legs and powerful jaws. Lizards With their blue tongues, beaded skin, and daggerlike claws, Nile monitor lizards are prized exotic pets. But, like Burmese pythons, when these animals become full-size, their owners sometimes release them. Nile monitor lizards are now living in canals in Cape Coral, Florida Cape Coral is a city in Lee County, Florida, United States. The population was 102,286 at the 2000 census. According to the U.S Census estimates of 2006, the city had a population of 151,389. [1], making it the largest city in Southwest Florida. , and may be migrating to other areas. Experts say that the lizards, which can grow to be seven feet long, have a nasty temper and a fierce bite. So far, the creatures haven't hurt any humans, but small pets are in danger. Wildlife officials are also concerned that Nile monitor lizards may be feeding on the eggs of the endangered burrowing owl bur·row·ing owl n. A small, long-legged owl (Speotyto cunicularia) of American prairies that nests in burrows dug by animals such as prairie dogs or rabbits. . Monk Parakeets With their squawking and swooping, as well as their colorful feathers, monk parakeets are hard to miss. These small birds have large--and noisy--colonies in 12 states, including Florida and Texas, and in much of the Northeast. Originally from South America South America, fourth largest continent (1991 est. pop. 299,150,000), c.6,880,000 sq mi (17,819,000 sq km), the southern of the two continents of the Western Hemisphere. , monk parakeets are often kept as pets. Ecologists think that the wild colonies developed from birds that escaped or were released. Some people enjoy seeing these tropical birds in the wild. But scientists worry that monk parakeets may be threatening native bird or plant species. Some fruit farmers in Florida claim the birds are damaging crops. Giant African Snails In 1966, a young boy smuggled smug·gle v. smug·gled, smug·gling, smug·gles v.tr. 1. To import or export without paying lawful customs charges or duties. 2. To bring in or take out illicitly or by stealth. three giant African snails into Miami, Florida “Miami” redirects here. For the Native American tribe, see Miami tribe. Miami is a major city in southeastern Florida, in the United States. It is the county seat of Miami-Dade County. Miami is a gamma world city with an estimated population of 404,048. . His grandmother later set them loose in the yard. The animals--about the size of an adult man's fist--spread quickly. Within a few years, they were causing millions of dollars' worth of damage to farm crops and other plant life. Besides destroying crops, some of the snails carry a parasite that can cause meningitis (an infectious disease Infectious disease A pathological condition spread among biological species. Infectious diseases, although varied in their effects, are always associated with viruses, bacteria, fungi, protozoa, multicellular parasites and aberrant proteins known as prions. ) in humans. Owning giant African snails is now illegal in the U.S. But they became popular as home and classroom pets, so some may still be living in pet owners' tanks. If you have one, notify the U.S. Department of Agriculture (USDA USDA, n.pr See United States Department of Agriculture. ). They'll help you get rid of it safely. Feral Cats How can one of America's favorite pets be an invasive species? Believe it or not, some cats are. Domestic cats are not native to the U.S. Early settlers brought them to America from other countries. When domestic cats run wild, they are called feral. Millions of feral cats roam the U.S. They prey on native birds, reptiles, and small mammals. No one complains when cats keep the number of rats and mice in check. But in certain areas, such as Hawaii, feral cats may be driving some rare songbirds to extinction. Non-pet Invaders Not all invasive species begin as pets. Take the coqui (koh-KEE) frog, for example. The size of a U.S. quarter, this amphibian amphibian, in zoology amphibian, in zoology, cold-blooded vertebrate animal of the class Amphibia. There are three living orders of amphibians: the frogs and toads (order Anura, or Salientia), the salamanders and newts (order Urodela, or Caudata), and the hitchhiked to Hawaii from Puerto Rico Puerto Rico (pwār`tō rē`kō), island (2005 est. pop. 3,917,000), 3,508 sq mi (9,086 sq km), West Indies, c.1,000 mi (1,610 km) SE of Miami, Fla. on plants. Its population exploded on Hawaii's largest island. The coqui frog gobbles up insects and spiders that are a necessary part of native songbirds' food supply. Another invader is the northern snakehead Noun 1. northern snakehead - a voracious freshwater fish that is native to northeastern China; can use fin to walk and can survive out of water for three days; a threat to American populations of fish , a fish that can be 3 feet long and weigh 15 pounds or more. Popular as food in China, it was imported live to U.S. fish markets and sold from tanks. But some were released into U.S. waterways. The snakehead devours amphibians amphibians members of the animal class Amphibia. Includes frogs, toads, newts, salamanders and cecilians all capable of living on land or in water. , other fish, aquatic birds, and even some small mammals. It's Up to You Whether invasive species arrive as pets, hitchhikers, or fresh food, once they become a problem, it is difficult--perhaps impossible--to get rid of them. The best defense is to keep them from becoming a problem in the first place. "If you're going to be a pet owner, do your homework," Snow recommends. "Ask, 'How big is this animal going to get, how much will it eat, and how much will it cost me to keep this pet for its lifetime?'" If you have a pet that you can't keep--for any reason--seek help from the USDA or a state or federal wildlife agency. Don't think that it will be "kinder" to set an animal free. No matter what species it is, it is likely to cause problems or suffer them in the wild. Even that cute little Easter bunny can become a serious problem if it isn't a native species. Words to Know * ecologists: a scientist who studies the interrelationship in·ter·re·late tr. & intr.v. in·ter·re·lat·ed, in·ter·re·lat·ing, in·ter·re·lates To place in or come into mutual relationship. in of organisms [living things Living Things may refer to:
* ecosystem: a community of plants and animals Plants and Animals are a Canadian indie-rock band from Montreal, comprised of guitarist-vocalists Warren Spicer and Nic Basque, and drummer-vocalist Matthew Woodley.[1] They are signed to Secret City Records. living in an environment that supplies what they need to survive and thrive. * invasive species: species that enter new ecosystems and multiply, harming native species and their habitats. Think About It 1. Not all pets released into the wild will become dangerous predators. What harm might befall be·fall v. be·fell , be·fall·en , be·fall·ing, be·falls v.intr. To come to pass; happen. v.tr. To happen to. See Synonyms at happen. pets that have no natural defenses against native wildlife? 2. If a pet owner can't take care of an animal anymore, where should he or she take it? Explain. What else might be done to prevent the problem of invasive species? Web Watch: National Invasive Species Information Center www.invasivespeciesinfo.gov LESSON PLANS * Objective Students should be able to: * understand the consequences of releasing unwanted pets into the wild. * Word to Know * feral: having escaped from domestication domestication Process of hereditary reorganization of wild animals and plants into forms more accommodating to the interests of people. In its strictest sense, it refers to the initial stage of human mastery of wild animals and plants. (tamed state) and become wild. * Background Invasive species are a worldwide problem. As travel becomes faster, the spread of species--intentional or inadvertent--becomes harder to limit. Increasing awareness of the problems caused by invasive species and of the need for coordinated efforts to deal with them has led to the creation of a number of U.S. and international agencies, including the National Invasive Species Information Center (invasivespeciesinfo.gov), founded in 2005. * Critical Thinking MAKING PREDICTIONS: Which animal in this article could be most harmful to the environment? Why? (Answers will vary, but should include supporting reasons--for example, the giant African snail, because it can spread disease among humans, or Nile monitor lizard, because it eats any animal it can kill.) DEFENDING AN ARGUMENT: Is wearing animal for or eating meat unethical? Why or why not? What rights, if any, should an animal have? (Answers will vary.) * Activity AN IN-DEPTH LOOK: Have each student research an animal native to your area, then prepare a brief presentation for the class, answering such questions as: How does the animal get food? How does it keep away predators? What factors, if any, threaten its survival? STANDARD SOCIAL STUDIES, GRADES 5-8 * People, places, and environments: Releasing a pet into the wild can result in great harm to the natural environment. * Silverstein, Alvin, et al., Pocket Pets (Lerner Publishing Group, 2000). Grades 4-7. * Stein, Sara, Great Pets! (Storey Books, 2003). Grades 4-6. WEB SITES * Global Invasive Species Database issg.org/database * Invasive Species Photos news.nationalgeographic.com/news/2004/6/photogalleries/invasive QUICK QUIZ * Match each invasive species in the left column with the matching description in the right column.
--1. Burmese python A. popular as food in China
--2. coqui frog B. has a fierce bite
--3. giant African snail C. can grow to 20 feet
long
--4. Nile monitor lizard D. the size of a quarter
--5. northern E. may carry a meningitis-causing
snakehead parasite
ANSWERS 1. E 2. D 3. E 4. B 5. A |
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