According to a report, the US Fish and Wildlife Service has recently rejected a proposal to put the North American wild horse under the list of endangered or threatened species.

The proposal of listing tens of thousands of mustangs under the list of endangered species was kept forward by Friends of Animals and The Cloud Foundation in last summer.

Both the petitioners seek Endangered Species Act protection the North American wild horse, which they say are under threat of extinction on federal land across 10 Western states ranging from California to Montana.

The conservationists stressed on the point that the horses are a distinct population segment that has evolved as a native species over several thousands of years separate from domesticated horses.

But the US Fish and Wildlife Service rejected the proposal concluding that a horse is a horse. "Although behaviors between domestic and wild animals of the same species may differ ... the petition does not present substantial information that the North American wild horse may be separate from other populations of horse as consequence of behavioral differences", the agency stated.

According to the petition, habitat of mustang has decreased almost 40% since President Richard Nixon signed the Free Roaming Wild Horse and Burro Act into law in 1971.

Bureau of Land Management's website stated that American wild horses descended from domestic horses. Some of these were brought by European explorers in the late 15th and 16th centuries.

Jennifer Barnes, a lawyer for Friends of Animals based in suburban Denver, said in a statement that the group is quite disappointed and confused about the agency's decision.