Many of the animal species at risk of extinction in the United States have not made it onto the country's official Endangered Species Act (ESA) list, according to new research from the University of Adelaide.

The International Union for Conservation of Nature said on Thursday that the Western Black Rhino of Africa has been declared officially extinct.

A new study by top global fisheries experts presents an alarming assessment of several economically important fish populations.

Tuna species are in more danger now than ever before, as two new species were added to the IUCN Red List of Threatened Species this week.

A species of antelope that is possibly the source for the legend of the unicorn has been successfully reintroduced into its native habitat after having been hunted to all but extinction.