South Asian river dolphin The sphincter-like structure is capable of sensing light, and may be able to sense the direction from where the light was emitted. However, the muddy waters, or low light conditions, that the "Platanista gangetica" inhabit negate the use of the little vision that remains. The Ganges subspecies shows object-avoidance behavior in both the consistently heavily murky waters of its habitat and in clear water in captivity, suggesting that it is capable of using echolocation effectively to navigate and forage for prey. However, there is limited information on how extensively vocalization is utilized between individuals. This subspecies of river dolphin is
Endangered Species Act of 1969 passed prior to the 1969 act, and set up a list of species native to the United States that qualified as endangered. The animals on this list were then afforded certain protections from the National Wildlife Refuge System. For example, the Endangered Species Preservation Act was in part dedicated to raising awareness of endangered species of birds like the peregrine falcon, and to "conserve, protect, restore, and propagate certain species of native fish and wildlife". Despite these protections, however, researchers found that the act was insufficient. This led to the passage of the Endangered Species Conservation Act of 1969. The