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 1973 landowner will not be required to do more than already agreed upon in the CCA. The Experimental Population Provision encourages introductions of species into formerly occupied or new habitat without the full range of legal restrictions for endangered species. The provision was added to the act in 1982 to encourage landowner support for species survival and recovery. Experimental populations could be used for the assisted migration of endangered species. To delist species, several factors are considered: the threats are eliminated or controlled, population size and growth, and the stability of habitat quality and quantity. Also, over a dozen species have