North American River Otter
The river otter, Lontra canadensis, is the most elusive aquatic mammal in Pennsylvania. It belongs to the mustelid, or weasel, family. Otters are extremely curious and playful and often slide on ice or snow, shoot down slick muddy banks into creeks, play with food, sticks and stones, and wrestle each other. Few people are lucky enough to see otters in the wild, but those who do, rarely forget the experience.
Otters range throughout most of North America, north of Mexico. In Pennsylvania, otters occur in every major river system and are absent only in watersheds with significant water-quality problems. Clean water supporting fish and other aquatic life is the foundation of good otter habitat. Water pollution, including strip mine runoff, industrial waste and sewage, has made some Pennsylvania streams, lakes and rivers unfit for aquatic life. Much progress has been made in cleaning up the state's polluted waterways. Tough anti-pollution laws now protect these waters from returning to the crippled state they were in not long ago. Otter populations have benefited from these efforts and have responded positively to these habitat improvements. While otters sometimes live near towns and cities, they prefer wilder territory. Water quality, more than any other factor, will determine where otters will live.