There are anywhere from two to 50 million different species on Earth today, and the number… There are anywhere from two to 50 million different species on Earth today, and the number of them that have been identified increases yearly.

But for almost every new species found, there is a species that continues to die off and head into extinction.

The endangered species list may soon gain newly waning animals on its rolls, and the U.S. Fish and Wildlife service has removed others.

With the official extinction of various mountain wolves and the Oregon bison, among other species, the American government decided that a change was imperative to the survival and replenishment of American species that were nearing extinction.

In 1973, Congress passed the Endangered Species Act. This Act encourages the protection of animals within the United States that have a critical population in their current habitat. The official Endangered Species Act can be found on the U.S. Fish and Wildlife Service’s Web site.

The document states, “The United States has pledged itself as a sovereign state in the international community to conserve to the extent practicable the various species of fish or wildlife and plants facing extinction.”

George Jugovic, adjunct professor at Pitt’s School of Law and senior council for the Citizens for Pennsylvania’s Future, teaches a wildlife law course at Pitt.

“The Endangered Species Act is very unique in that it provides some heightened protection for animals bordering on extinction. The Act is to not only ensure an end to species’ decline, but for a full reversal so the population can actually grow,” Jugovic said.

So far the Act has been serving its purpose in some cases. For instance, it has successfully recuperated the Yellowstone National Park’s population of grizzly bears that had been on the endangered species list for nearly three decades.

On March 27, the U.S. Fish and Wildlife Service announced the removal of this particular species of grizzly bear from the endangered species list.

“Since the early 1990s, the Yellowstone population has grown at a rate of 4 percent to 7 percent per year. Grizzly range in the Yellowstone Ecosystem has increased 48 percent since they were listed, and biologists have sighted bears more than 60 miles from what was once thought to be the outer limits of their range,” the press release said.

The American bald eagle, the first species to be listed under the Endangered Species Act, is now about to be removed from the endangered species list thanks to the continued efforts from the Golden Eagle Protection Act, as well as the Endangered Species Act.

Today, there are several other protection acts for specific animals in the United States like the Wild Horse and Burros Act, Marine Mammal Protection Act and the Migratory Bird Treaty Act.

“Species do not become smaller in population because of people hunting and killing them, but because of a change in their habitat. In the United States, there is an urban sprawl for land, and it’s taking away a lot of animals’ homes. Also, the building of dams on rivers leads to an elimination of a number of fish species,” Jugovic said.

Recently put on the spotlight, some polar bear populations are in the process of being put on the endangered species list.

More specifically, the polar bear population in Canada is catching the most media attention.

“The warming temperatures are melting much of the ice in which these bears need. In Canada, one type of polar bear has suffered a 22 percent decline in recent years,” Jugovic said.

In the last 10 years, there has been a 7 percent decline in sea ice; with such a rapid decrease in some polar bear populations, it will only be a matter of years until they are listed as an endangered species.

Here at Pitt, a few programs to educate environmental studies students like student William Prince are offered during the summer.

“This summer I’m doing field work at the Pymatuning Lab about 20 minutes away from Pitt to do field work with ecosystems. There’s another program through the Honors College that is a field study at Yellowstone National Park,” Prince said.