Many Endangered Species Making Remarkable Comebacks

As their numbers plummet, jaguars, polar bears and leatherback sea turtles might have hope of survival in light of the success stories of some of their fellow creatures.

Human activity threatens 99 percent of all species, according to the World Conservation Union (IUCN). Plants and animals are going extinct at a rate 1,000 to 10,000 times higher than what would occur naturally, some researchers say. One recent study concluded that a quarter of the world's plant and vertebrate animal species would face extinction by 2050.

However, human conservation efforts are working to boost specific populations.

The IUCN keeps watch over the world's biodiversity with its publication of its Red List every two years, meant to keep the public and policy makers aware of threatened plant and animal species.

In the United States, the Endangered Species Act works to protect plants and animals from becoming extinct. On top of federal laws, individual states offer added protection and conservation mandates.

As our national bird, the bald eagle earned a prime spot on the Endangered Species List in 1973. The population has bounced back after the government's ban of DDT, designation of protected breeding grounds, and establishment of captive breeding programs.

Florida's Fish and Wildlife Conservation Commission recently removed the bald eagle from its list of threatened species in the sunshine state.

As well, the U.S. Fish and Wildlife Service plans to remove the bald eagle from the federal Endangered Species List.

Hundreds of species in North America have bounced back from precarious populations, thanks at least in part to the Endangered Species Act, according to the Center for Biological Diversity.

— Yellowstone National Park has been a haven for wild bison, where a population that has existed since prehistoric times now thrives.

— Since all California condors left in the wild were taken into captivity in 1987, the birds have fared well, both in captivity and back in the wild.

— Arizona Game and Fish Department biologists named 2005 the "best year yet" for black-footed ferrets.

— Listed as an endangered species in 1967, the American alligator has since rebounded, but remains protected against hunting because of its uncanny resemblance to the endangered American crocodile.

Grizzly bears roaming around Yellowstone might soon be removed from the Endangered Species List.

It's not all roses for those that make the list. Scientists' best intentions to study endangered pupfish near Death Valley just made the situation worse, unintentionally killing one-third of the remaining population last summer.

Top 10 Success Stories:

10. American alligator: Hunting quotas and egg collection programs cracked the gator decline in the southeastern United States. Landowners collect eggs, when alligators are most vulnerable to predators, sell some of them to gator ranchers, and return the rest of the hatch to the wetlands.

9. South African dragonflies: An invasion of non-native eucalyptus trees blocked the sun shining on the South African habitat that dragonflies depend on. A national program to cut down the shady trees has brought light to the insects, and jobs to local people.

8. Goliath grouper: As the biggest fish in the coral reef at 700 pounds, fishermen have coveted a Goliath catch, forcing its population to crash in just 30 years. A 1990s fishing ban in the Caribbean has helped southern Floridian grouper youngsters rebound.

7. Blue poison frog: Its flashy looks made this small-town frog a top-selling trinket in the international pet trade. The frog leaped back from near-extinction with protection from collectors, captive breeding and conservation of its little habitat in Surinam.

6. Grizzly bear: Protection on the Endangered Species List is ending for the grizzlies. About 600 bears live near Yellowstone, up from 271 left in 1975. Populations are in such great shape, say experts some states, that they could become open game for hunting season.

5. Koala: Hunted to near-extinction for its fur in the early 20th century, native Australian koalas are thriving in protective reserves. In fact, isolated populations and those on predator-free islands have reached pesky plague proportions.

4. Black-footed ferret: Proclaimed extinct prematurely, the last 120 feral ferrets were discovered in 1981 after a Wyoming farm dog brought one home in its mouth. A decade later, a triumphant captive breeding program has released 2,300 ferrets into the wild.

3. California condor: The California condor's not winning any beauty pageants, but its rise from the ashes earns the largest North American bird a Top 10 spot. Its 1987 extinction in the wild make today's 125 free-flying birds a remarkable tale of nurture and nature.

2. American bison: More than 50 million bison roamed the North American prairies before cowboys headed West and hunted the population down to as few as 750 animals. In 1905, the American Bison Society conserved land for herds and introduced captively bred individuals whose descendents now number about 350,000.

1. Bald eagle: In February, the U.S. Fish and Wildlife Service announced it could safely consider kicking our country's national symbol off the federal Endangered Species List. Survivors of the banned poison DDT, the eagles' numbers soared from 417 nesting pairs in 1963 to 9,250 nesting pairs today.

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