Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Occupancy–abundance relationship wikipedia , lookup
Introduced species wikipedia , lookup
Latitudinal gradients in species diversity wikipedia , lookup
Island restoration wikipedia , lookup
Reconciliation ecology wikipedia , lookup
Biodiversity action plan wikipedia , lookup
Species At Risk Keystone Umbrella Indicator Florida panther Wolf Grizzly Bear Salmon Prairie Dogs Bison Sage Grouse Frogs Many of the species the National Wildlife Federation (NWF) works to protect are “keystone,” “umbrella,” or “indicator” species. • Keystone species: Keystone species are species that enrich ecosystem function in a unique and significant manner through their activities, and the effect is disproportionate to their numerical abundance. Their removal initiates changes in ecosystem structure and often loss of diversity. These keystones may be habitat modifiers (ie. cottonwoods, rushes and ironwood), keystone predators (ie. puma and coyote) or keystone herbivores (ie. prairie dog and beaver). • Umbrella species: An umbrella species are typically large and require a lot of habitat. By protecting this larger area, other species are protected as well. Umbrella species generally have the following characteristics: their biology is well known, they are easily observed or sampled, they have large home ranges, they are migratory, and have a long lifespan. • Indicator species: A species that is particularly sensitive to environmental conditions and therefore can give early warning signals about ecosystem health. Because they are so sensitive, a decline in indicator species’ health can signal air and water pollution, soil contamination, climate change or habitat fragmentation. Indicator species are often threatened or endemic (native) species. Continue reading to learn more about some of the species that NWF is working to protect. Many of the species fall into more than one category. Scientists still debate exactly how to classify some species because we are always discovering new information about the biology of these creatures. Top Predators Panthers The Florida panther is a subspecies of cougar, a creature with many common names: catamount, puma, mountain lion and red lion, among others. Scientists know the Florida panther as Felis concolor coryi. There are now less then 100 Florida panthers left, all in the southern tip of Florida. They’re the last remnants of a population of native cougars that once ranged across most of the southeastern U.S. The Florida panther is both a keystone and an umbrella species. Wolves Prior to being granted federal protection, wolves were killed by farmers and ranchers who were encouraged by a federally sponsored wolf-extermination program. Today, the greatest threat to the wolf is still the misconception that they endanger people and livestock. Wolves are considered both a keystone and umbrella species. Grizzly Bears The non-Alaskan grizzly bear was added to the federal Endangered Species List as a threatened species in 1975. Ranching and farming have driven the grizzly from the open plains. Today, the species lives mostly in mountains and forests. In the nineteenth century, the bear nearly went extinct in the lower 48 states. Grizzly bears fall into all three categories of keystone, umbrella, and indicator species. Fish Salmon Dams, deforestation, sprawl, river channelization and pollution are putting pressure on our remaining salmon. Fish farms are adding to the threat by increasing the likelihood of accidental interbreeding and disease transmission. Salmon are keystone species as well as indicator species. Other Mammals Prairie Dogs There are five species of prairie dog, and each is a keystone in its respective ecosystem. Prairie dogs fertilize the soil and increase the protein content and digestibility of rangeland grasses. But because they eat grass shared by livestock, ranchers often see them as pests. Eradication programs, disease, recreational shooting, poisoning, and habitat destruction have reduced prairie dog populations to only about 2 percent of their historical range. Prairie dogs are keystone and indicator species. Black-tailed Prairie Dogs The black-tailed prairie dog (Cynomys ludovicianus) occupies narrow bands of dry plains stretching from central Texas to Canada. The black-tailed prairie dog’s population has plummeted to roughly one percent of its historic level, prompting the National Wildlife Federation in July 1998 to petition the U.S. Fish and Wildlife Service to list the species as threatened under the Endangered Species Act. White-tailed Prairie Dog The white-tailed prairie dog (C. leucurus) inhabits Colorado, Utah, Wyoming and Montana, and has vanished from 92 percent of its historical range. This particular species is highly vulnerable to an exotic disease called sylvatic plague, which has devastated its numbers. Gunnison’s Prairie Dog Gunnison’s prairie dogs, (C. gunnisoni), live in the Four Corners area, in elevations ranging from 5000 to 11,000 feet. Mexican Prairie Dog The Mexican prairie dog, (C. mexicanus), is an endangered species that lives only within certain parts of Mexico. Utah Prairie Dog The Utah prairie dog (C. parvidens), listed as endangered in 1973, is the smallest of all prairie dogs. The species was downlisted - perhaps inappropriately - to threatened status in 1984. Conservationists have been unsuccessful in helping prairie dogs thrive on public land, which is the main goal of the current recovery plan. Much of this land is slated for development into farms or residential housing. Bison More than 50 million bison once thundered across the Great Plains. Victims of domestication, habitat loss and needless slaughter, today bison survive only in remote pockets of our country's prairie grasslands. Bison are an umbrella species. Birds Sage Grouse As its name suggests, the sage grouse is entirely dependent on healthy sage grasslands habitat, which was once abundant throughout the West. To date, the birds have disappeared from as much as 50 percent of their former habitat. Sage grouse are considered an umbrella species. Amphibians Frogs Amphibians are declining at an alarming rate worldwide. Frogs are very sensitive to changes in their environment and therefore serve as indicator species for ecosystem health. Frogwatch USA is a long-term frog and toad monitoring program managed by the National Wildlife Federation in partnership with the United States Geological Survey. Frogwatch’s mission is to: • Collect vital information about frog and toad species in the U.S. • Promote an appreciation for the diversity of frog and toad species • Foster an understanding of the importance of protecting wetland habitats • Provide an opportunity to learn about and establish a closer relationship with the natural environment Citizen-scientists throughout the United States volunteer to monitor their local wetlands and to protect imperiled amphibians. Visit http://www.nwf.org/frogwatchUSA/ to find out how you can become a Frogwatch USA volunteer. For more information contact: Corry Westbrook National Wildlife Federation 1400 Sixteenth Street, NW Suite 501 Washington, DC 20036 Email: [email protected] Website: www.nwf.org