The International Union for the Conservation of Nature (IUCN) has published an update to its “Red List” of threatened animals, and the news was grim for a number of species across the planet – especially the rhinoceros. The organization has declared the wild black rhino extinct in West Africa, and says that a number of other subspecies of rhinos may already be gone as well.

IUCN officials say that poaching is to blame for the loss of the black rhino, whose horn is seen as highly valuable in traditional medicines and remedies across parts of Asia. Demand for those horns on the black market is so high, that poachers are willing to face stiff jail terms, or even death, in order to acquire them. As a result, this particular subspecies has been hunted to extinction in West Africa, where there are few security measures in place to protect the creatures.

The Red List also warns of the potential loss of the northern white rhino, which calls central Africa home. The IUCN believes that it is also on the brink of extinction, as is the Javan rhino, which is no longer found outside of Java as well.

According to the organization, 25% of the world’s mammal species are now in danger of becoming extinct, despite conservation efforts across the planet. They also warn that 40% of Madagascar’s reptiles are at risk, although new conservation zones there have helped to ease a possible impending disaster there.

All is not lost however, as the latest IUCN report also cites the success of the re-introduction of the Przewalski’s horse into the wild. The animal was also declared extinct outside of captivity back in 1996, but careful management has allowed the creature to be reintroduced to their natural habitat along the steppes of China and Mongolia. The herds are now believed to have grown to more than 300 in number.

The hope is that a similar program could eventually be used to bring the rhino back to its home as well. Before that can happen however, the threat of poaching needs to be quashed once and for all.