is the original animal under any threat of extinction?
Yes, trapping, loss or degradation of aquatic habitats through filling of wetlands, and development of coal, oil, gas, tanning, timber, and other industries, result in decline in the count of these species.
North American river otter
Trapping, loss or degradation of aquatic habitats through filling of wetlands, and development of coal, oil, gas, tanning, timber, and other industries, resulted in extirpations, or declines, in North American river otter populations in many areas. 
where do river otters go in the winter During winter, the North American river otters heavily use openings in the ice, and may excavate passages in beaver dams for accessing open water. what are these creatures? The North American river otter also known as the northern river otter or common otter, is a semiaquatic mammal endemic to the North American continent found in and along its waterways and coasts. how is their temperament? are active year-round, and are most active at night and during crepuscular hours. They become much more nocturnal in the spring. what do they feed on? They eat aquatic and semiaquatic animals. what are the second type ? They refer to various types of animals that spend part of their time in water, or plants that naturally grow partially submerged in water. any particular examples? UNANSWERABLE do such plants exist as well? UNANSWERABLE
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North American river otter [SEP] Threats
Trapping, loss or degradation of aquatic habitats through filling of wetlands, and development of coal, oil, gas, tanning, timber, and other industries, resulted in extirpations, or declines, in North American river otter populations in many areas. In 1980, an examination conducted on U.S. river otter populations determined they were extirpated in 11 states, and had experienced drastic lapses in 9 others. The most severe population declines occurred in interior regions where fewer aquatic habitats supported fewer otter populations. Although the distribution became reduced in some regions of southern Canada, the only province-wide extirpation occurred on Prince Edward Island. During the 1970s, improvements in natural resource management techniques emerged, along with increased concerns about North American river otter population declines in North America.